Mercurial > ~dholland > hg > ag > index.cgi
annotate anagram/guisupport/helpdata.src @ 24:a4899cdfc2d6 default tip
Obfuscate the regexps to strip off the IBM compiler's copyright banners.
I don't want bots scanning github to think they're real copyright
notices because that could cause real problems.
| author | David A. Holland |
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| date | Mon, 13 Jun 2022 00:40:23 -0400 (2022-06-13) |
| parents | 13d2b8934445 |
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| rev | line source |
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1 Accept Action |
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2 |
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3 The accept action is one of the four actions of a |
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4 traditional �parsing engine�. The accept action is |
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5 performed when the �parser� has succeeded in identifying |
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6 the goal, or �grammar token� for the �grammar�. When |
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7 the parser executes the accept action, it sets the �exit_flag� |
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8 field in the �parser control block� to AG_SUCCESS_CODE and returns |
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9 to the calling program. The accept action is thus the last action of |
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10 the parsing engine and occurs only once for each successful execution |
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11 of the parser. |
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12 |
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13 If the grammar token has a non-void value, you may |
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14 obtain its value by calling the �parser value function� |
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15 whose name is given by <parser name>_value, that is, |
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16 by appending "_value" to the �parser name�. |
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17 ## |
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18 |
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19 Parser Value Function, Return Value |
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20 |
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21 The value assigned to the �grammar token� in your parser |
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22 may be retrieved by calling the parser value function after |
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23 the parser has finished. The name of this function is given |
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24 by <�parser name�>_value. The return type of the function |
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25 is the type assigned to the grammar token. |
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26 |
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27 If you have set the �reentrant parser� switch, the parser |
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28 value function takes a pointer to the �parser control block� |
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29 as its sole argument. Otherwise, it takes no arguments. The |
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30 value function is not defined if the grammar token has type "void". |
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31 ## |
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32 |
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33 AG_PLACEMENT_DELETE_REQUIRED |
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34 |
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35 When the �wrapper� option is specified, the wrapper |
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36 template class that AnaGram defines uses a "placement |
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37 new" operator to construct the wrapper object on the |
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38 �parser value stack�. The MSVC++ 6.0 compiler requires, |
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39 in this situation, that a corresponding "placement |
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40 delete" operator be defined. Other C++ compilers, |
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41 notably MSVC++ 5.0, generate an error message if |
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42 they encounter the definition of a "placement delete" |
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43 operator. |
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44 |
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45 Accordingly, AG_PLACEMENT_DELETE_REQUIRED is used to determine |
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46 whther a "placement delete" operator should be defined. |
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47 |
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48 AG_PLACEMENT_DELETE_REQUIRED is defined to be 1 if you are using MSVC++ |
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49 6.0 or greater, 0 otherwise. You can override the automatic definition of |
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50 AG_PLACEMENT_DELETE_REQUIRED by defining it in the �C prologue� section |
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51 of your grammar. Set it to a non-zero value to force the "placement |
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52 delete" definition, zero to skip the definition. |
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53 |
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54 ## |
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55 |
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56 ag_tcv |
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57 |
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58 ag_tcv is an array AnaGram includes in your �parser�. |
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59 Your parser uses ag_tcv to translate external codes to |
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60 the internal token numbers that AnaGram uses. It uses |
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61 the actual input code to index the ag_tcv array to |
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62 fetch a �token number�. The token number is then used |
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63 to identify the input token. |
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64 ## |
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65 |
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66 Allow macros |
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67 |
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68 "Allow macros" is a �configuration switch� which |
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69 defaults to on. When it is set, i.e., on, �reduction |
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70 procedure�s will be implemented as macros if they are |
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71 sufficiently simple. This makes your �parser� somewhat |
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72 more compact but makes it somewhat more difficult to |
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73 debug. It's a good idea to turn this switch off for |
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74 debugging. |
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75 ## |
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76 |
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77 Analyze Grammar |
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78 |
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79 The Analyze Grammar command will scan and |
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80 analyze your �syntax file�, and create a number of |
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81 tables summarizing your grammar. |
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82 |
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83 Analyze Grammar does not create any �output files�. |
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84 To create a �parser�, use the �Build Parser� command. |
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85 You would probably use Analyze Grammar, rather than Build Parser, during |
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86 initial development of your �grammar�. |
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87 |
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88 You can use �File Trace� and �Grammar Trace� as soon as you have |
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89 analyzed your grammar. It is not necessary to build a parser first. |
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90 ## |
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91 |
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92 Attribute Statement |
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93 |
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94 Attribute statements are used in �configuration |
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95 sections� of your �syntax file� to specify certain |
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96 properties for �token�s, �character set�s, or other |
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97 units of your grammar. The attribute statements |
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98 available are: |
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99 �disregard� |
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100 �distinguish keywords� |
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101 �enum� |
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102 �extend pcb� |
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103 �hidden� |
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104 �left� |
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105 �lexeme� |
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106 �nonassoc� |
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107 �rename macro� |
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108 �reserve keywords� |
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109 �right� |
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110 �sticky� |
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111 �subgrammar� |
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112 �wrapper� |
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113 ## |
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114 |
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115 Auto init |
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116 |
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117 Auto init is a �configuration switch� which defaults to |
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118 on. It controls the initialization of any �parser� that |
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119 it is not �event driven�. When it is set to on, your |
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120 parser is automatically initialized every time it is |
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121 called. This is the situation you will normally use. On |
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122 occasion, however, it is desirable to call a parser |
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123 several times without reinitializing it. In this case, |
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124 you may set the auto init parameter to off and then |
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125 call the �initializer� yourself whenever it is |
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126 appropriate. |
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127 ## |
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128 |
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129 Auto resynch |
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130 |
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131 "Auto resynch" is a �configuration switch� which |
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132 defaults to off. You may use it to specify �automatic |
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133 resynchronization� as an �error recovery� mechanism. |
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134 |
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135 Setting the "auto resynch" switch causes AnaGram to |
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136 include an automatic �resynchronization� procedure in |
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137 your �parser�. The resynchronization procedure will be |
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138 invoked when your parser encounters a �syntax error� |
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139 and will skip over input until it finds input |
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140 characters or �tokens� consistent with its state at the |
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141 time of the error. |
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142 |
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143 An alternate technique, �error token resynchronization�, |
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144 uses an �error token� which you include in your grammar. |
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145 ## |
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146 |
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147 Automatic Resynchronization |
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148 |
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149 Automatic �resynchronization� is one of several �error |
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150 recovery� options available as part of parsers built by |
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151 AnaGram. You enable automatic resynchronization by |
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152 setting the �auto resynch� �configuration switch�. If |
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153 your parser includes automatic resynchronization it will |
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154 incorporate a heuristic procedure which will skip over |
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155 input tokens until it finds a token which makes sense |
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156 with respect to one or another of the �production�s |
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157 active at the time of the �syntax error�. |
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158 |
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159 The purpose of the resynchronization procedure is to |
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160 provide a simple way for your parser to proceed in the |
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161 event of syntax errors so that it can find more than one |
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162 syntax error on a given pass. The resynchronization |
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163 procedure uses a heuristic based on your own syntax. |
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164 AnaGram itself uses this technique to resynchronize |
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165 after syntax errors in its input. |
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166 |
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167 A disadvantage to using this resynchronization technique |
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168 is that the resynchronization procedure turns off all |
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169 �reduction procedure�s. Because of the error, a number |
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170 of reduction procedures, which normally would be |
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171 executed, will be skipped. The parameters for any |
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172 reduction procedures that might be called later would be |
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173 suspect and could cause serious problems. It seems more |
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174 prudent simply to shut them down. |
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175 |
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176 If you use the automatic resynchronization procedure, |
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177 you must also specify an �eof token� so that the |
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178 synchronizer doesn't inadvertently skip over the end of |
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179 file. |
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180 |
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181 An alternative technique for resynchronization is called |
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182 �error token resynchronization�. |
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183 ## |
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184 |
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185 Auxiliary Trace |
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186 |
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187 An Auxiliary Trace is a pre-built grammar trace which |
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188 you may select from the �Auxiliary Windows� popup menu for |
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189 most windows which display parser state information. |
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190 The Auxiliary Trace provides a path to the state |
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191 specified in the highlighted line of the primary window. |
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192 |
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193 When obtained |
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194 from the Parser Stack pane of the �File Trace� or �Grammar Trace�, the |
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195 Auxiliary Trace is simply a copy of the current status of these |
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196 traces so you can explore your alternatives while still retaining the |
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197 status of the original trace for reference. |
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198 ## |
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199 |
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200 Auxiliary Windows |
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201 |
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202 From most AnaGram windows you can pop up an Auxiliary Windows |
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203 menu by clicking the right mouse button or by pressing Shift F10. |
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204 Auxiliary Windows may |
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205 have Auxiliary Windows of their own. |
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206 |
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207 Windows with a cursor bar (highlighted line): |
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208 The windows available in the Auxiliary Windows menu depend on the |
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209 grammar elements identified by the cursor bar in the parent window. If |
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210 the cursor bar identifies a �parser state�, there will be windows that |
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211 describe the state. If the cursor bar identifies a �grammar rule�, |
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212 there will be windows that describe the rule. If the cursor bar |
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213 identifies a �token�, there will be windows that describe the token. In |
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214 the case of a �marked rule�, token windows will describe the marked |
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215 token, if any. In some cases, specialized pre-built grammar traces |
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216 such as the �Conflict Trace� or �Auxiliary Trace� are on the menu. |
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217 |
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218 Help windows: |
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219 For Help windows, the Auxiliary Windows menu will show all the |
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220 available links to other �Help topics� from this window. �Using Help� |
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221 is always available. |
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222 ## |
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223 |
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224 Backtrack |
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225 |
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226 If your �parser� does not continue after encountering a |
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227 �syntax error�, you can speed it up and make it a |
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228 little smaller by turning off the backtrack |
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229 �configuration switch�. If backtrack is on, AnaGram |
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230 configures your parser so that in case of syntax error |
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231 it can undo any �default reductions� it might have made |
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232 as a consequence of the erroneous input. The purpose of |
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233 such an undo function is to identify the proper �error |
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234 frame� and to maximize the probability of being able to |
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235 recover gracefully. |
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236 ## |
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237 |
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238 Empty Recursion |
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239 |
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240 This warning message tells you that the recursive step of the |
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241 specified �recursive rule� can be completely matched by �zero |
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242 length� tokens, i.e., by nothing at all. |
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243 The result is potentially an infinite loop in the generated �parser�. |
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244 The specified rule is an expansion rule of the specified token. |
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245 |
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246 Because of the possibility of encountering an infinite loop while parsing, |
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247 AnaGram turns off its �keyword anomaly� analysis if empty recursion is |
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248 found. The �File Trace� function is also disabled for the same reason. |
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249 |
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250 The �circular definition� of a token has the same effect as an |
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251 empty recursion, in that no additional input is required to match |
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252 the recursive rule. |
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253 |
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254 ## |
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255 Keyword Anomaly analysis aborted: empty recursion |
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256 |
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257 The �keyword anomaly� analysis has been turned off, since the presence of |
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258 �recursive rule�s with �empty recursion� can cause infinite loops in the analysis. |
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259 |
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260 ## |
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261 |
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262 Keyword Anomaly analysis aborted: circular definition |
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263 |
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264 The �keyword anomaly� analysis has been turned off, since the presence of |
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265 a �circular definition� can cause infinite loops in the analysis. |
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266 |
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267 ## |
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268 |
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269 File Trace disabled: empty recursion |
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270 |
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271 Because of the presence of �recursive rule�s with �empty recursion� in this grammar and |
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272 the infinite loops that can ensue, the �File Trace� function has been |
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273 disabled. |
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274 |
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275 ## |
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276 |
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277 File Trace disabled: circular definition |
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278 |
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279 Because of the presence of a �circular definition� in this grammar and |
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280 the infinite loops that can ensue, the �File Trace� function has been |
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281 disabled. |
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282 |
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283 ## |
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284 |
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285 |
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286 |
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287 Both Error Token Resynch and Auto Resynch Specified |
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288 |
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289 |
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290 |
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291 This �warning� message indicates that your �grammar� |
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292 defines an �error token� and also requests �automatic |
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293 resynchronization�. AnaGram will ignore the request |
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294 for automatic resynchronization and will provide �error |
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295 token resynchronization�. If you named a token "error" |
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296 but do not wish �error token resynchronization�, you can |
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297 either rename "error", or, in a �configuration |
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298 section�, you may explicitly specify the error token to |
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299 be something you don't otherwise use in your grammar: |
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300 [ error token = not used ] |
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301 ## |
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302 |
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303 Bottom Margin |
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304 |
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305 "Bottom margin" is an �obsolete configuration parameter�. |
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306 ## |
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307 |
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308 Bright Background |
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309 |
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310 "Bright background" is a �configuration switch� which |
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311 was used in the DOS version of AnaGram. It is no longer |
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312 used, but is still recognized for the sake of upward |
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313 compatibility with old �configuration file�s. |
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314 ## |
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315 |
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316 Build Parser |
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317 |
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318 You use the Build Parser command to create a �parser� based on your |
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319 �grammar�. The parser is a C file consisting of the �embedded C� (which |
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320 may include C++) code in your �syntax file�, your �reduction |
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321 procedure�s, a number of tables derived from your grammar |
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322 specification, and a �parsing engine� customized to your requirements. |
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323 |
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324 If you only wish to investigate your grammar and do not |
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325 wish to create �output files�, use the �Analyze |
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326 Grammar� command. |
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327 ## |
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328 |
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329 Build <file name> |
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330 |
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331 This item on the �Action Menu� is available when you have analyzed a |
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332 �grammar� but you have not yet built it. It builds the grammar |
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333 without reloading the �syntax file� from the disk. |
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334 ## |
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335 |
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336 Cannot Make Wrapper for Default Token Type |
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337 |
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338 This �warning� message occurs when AnaGram finds a token type that has |
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339 been previously defined as the �default token type� |
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340 listed in a �wrapper� statement. If a wrapper is needed for a |
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341 particular type, you must specify the �data type� explicitly |
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342 for each relevant �token�. |
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343 |
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344 As a result, a wrapper class has not been created for the specified token type. |
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345 ## |
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346 |
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347 Token with Wrapper cannot be Default Token Type |
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348 |
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349 This �warning� message indicates that an attempt has been made |
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350 to specify a class that has previously been listed in a �wrapper� |
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351 statement as the �default token type�. |
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352 If a wrapper is needed for a particular type, you must specify the |
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353 �data type� explicitly for each relevant �token�. |
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354 |
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355 As a result, the default token type has not been set. |
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356 ## |
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357 |
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358 Case Sensitive |
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359 |
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360 "Case sensitive" is a �configuration switch� which |
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361 defaults to on. When it is on, it instructs AnaGram to |
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362 build a parser for which all input is case sensitive. |
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363 When it is off, the AnaGram builds a parser which |
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364 ignores case for all input. |
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365 |
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366 If the �iso latin 1� configuration switch is turned |
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367 off, case conversion will be limited to characters |
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368 in the normal ascii range. When it is on, case |
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369 conversion will be done for all iso latin 1 characters. |
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370 |
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371 If you have other requirements for case conversion, |
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372 you may provide your own definition in your �embedded c� for the |
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373 �CONVERT_CASE� macro which is invoked to perform case |
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374 conversion on input characters. |
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375 |
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376 Note that the value of an input token is unaffected |
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377 by the case sensitive switch. When case sensitive is |
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378 off, 'a' and 'A' will be treated as the same input |
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379 token by the parser, but the �token value�s will |
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380 nevertheless be different. |
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381 ## |
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382 |
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383 C Prologue |
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384 |
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385 If you include a block of �embedded C� code at the very |
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386 beginning of your syntax file, it is called the "C |
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387 prologue". It will be copied to your �parser file� |
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388 before any of the code generated by AnaGram. You can |
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389 use the C prologue to ensure that copyright notices, |
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390 #include directives, or type definitions, for example, |
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391 occur at the very beginning of your parser file. |
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392 |
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393 If you specify a C or C++ type of your own definition, |
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394 you must provide a definition in the C prologue. |
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395 ## |
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396 |
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397 CHANGE_REDUCTION |
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398 |
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399 CHANGE_REDUCTION(t) is a macro which AnaGram defines in |
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400 your �parser file� if your �parser� uses �semantically |
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401 determined productions�. In your �reduction procedure�, |
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402 when you need to change the �reduction token� you can |
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403 easily do so by calling CHANGE_REDUCTION with the name |
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404 of the desired token as the argument. If the token name |
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405 has embedded spaces, replace the embedded spaces with |
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406 underline characters. |
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407 ## |
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408 |
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409 Character Constant |
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410 |
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411 You may represent single characters in your �grammar� by |
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412 using character constants. The rules for character |
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413 constants are the same as in C. The escape sequences |
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414 are as follows: |
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415 \a alert (bell) character |
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416 \b backspace |
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417 \f formfeed |
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418 \n newline |
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419 \r carriage return |
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420 \t horizontal tab |
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421 \v vertical tab |
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422 \\ backslash |
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423 \? question mark |
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424 \' single quote |
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425 \" double quote |
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426 \ooo octal number |
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427 \xhh hexadecimal number |
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428 |
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429 AnaGram treats a single |
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430 character as a �character set� |
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431 which contains only the specified character. Therefore you |
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432 can use a character constant in a �set expression�. |
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433 ## |
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434 |
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435 Character Map |
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436 |
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437 The Character Map table shows you the mapping of input |
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438 characters to �token numbers�. The �ag_tcv� table in |
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439 your parser is based on the information in this table. |
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440 |
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441 The fields in this table are: |
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442 character code |
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443 display character, if any (what Windows displays for this code) |
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444 �partition set number� |
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445 �token number� |
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446 �token representation� |
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447 |
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448 The display character will be what Windows displays for the character |
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449 code in the Data Tables font you have chosen. |
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450 ## |
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451 |
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452 Character Range |
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453 |
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454 A "character range" is a simple way to specify a |
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455 �character set�. There are two ways to represent a |
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456 character range in an AnaGram �syntax file�. |
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457 |
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458 The first way is like a �character constant�: 'a-z'. |
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459 |
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460 The second way allows somewhat greater freedom: |
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461 'a'..'z' |
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462 'a'..255 |
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463 ^Z..037 |
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464 -1..0xff |
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465 Here you use two arbitrary �character representations� |
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466 separated by two dots. If the two characters are out of |
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467 order, AnaGram will reverse the order, but will give |
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468 you a �warning�. |
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469 |
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470 More complex �character sets� may be specified by using |
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471 �union�, �difference�, �intersection�, or �complement� |
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472 operators. |
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473 ## |
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474 |
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475 Character Representation |
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476 |
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477 In an AnaGram �syntax file� you may represent a |
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478 character literally with a �character constant� or |
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479 numerically using decimal, octal or hexadecimal |
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480 representations following the conventions for C. Thus |
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481 'A', 65, 0101, and 0x41 all represent the same |
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482 character. Control characters can be represented using |
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483 the '^' character and either an upper or lower case |
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484 letter. Thus ^j and ^J are acceptable representations |
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485 of the ascii newline code. The rules for character |
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486 constants are identical to those in C, and the same |
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487 escape sequences are recognized. |
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488 ## |
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489 |
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490 Character Set |
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491 |
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492 In AnaGram grammars you can conveniently specify whole |
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493 sets of characters at a time. This avoids |
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494 needless repetition and complexity. |
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495 |
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496 Sets of characters may be defined in an AnaGram �syntax |
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497 file� in any of a number of ways. A single character is |
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498 taken to represent a character set consisting of a |
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499 single element. (See �character representation�.) You |
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500 can also specify a set consisting of a range of |
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501 characters (see �character range�) and perform the |
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502 familiar set operations, union, intersection, difference |
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503 and complement. |
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504 |
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505 All the sets you define in your syntax file are |
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506 summarized in the �Character Sets� window. |
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507 |
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508 The �union� of two character sets, represented by a '+', |
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509 contains all characters that are in one or another of |
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510 the two sets. Thus, 'A-Z' + 'a-z' represents the set of |
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511 all upper and lower case letters. |
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512 |
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513 The �intersection� of two character sets, represented |
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514 by a '&', contains all characters that are in both |
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515 sets. Thus, suppose you have the �definitions� |
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516 letter = 'A-Z' + 'a-z' |
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517 hex digit = '0-9' + 'A-F' + 'a-f' |
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518 Then (letter & hex digit) contains precisely upper and |
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519 lower case a to f. |
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520 |
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521 The �difference� of two character sets, represented by |
|
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522 a '-', contains all characters that are in the first |
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523 set but not in the second set. Thus, using the same |
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524 definitions as above, (letter - hex digit) contains |
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525 precisely upper and lower case g to z. |
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526 |
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527 The �complement� of a character set, represented by a |
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528 preceding '~', represents all characters in the |
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529 �character universe� which are not in the given set. |
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530 Suppose you have defined a set, �eof�, which consists of |
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531 the characters which represent end of file. Then, in |
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532 your grammar where you wish to accept an arbitrary |
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533 character, what you really want is anything but an end |
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534 of file character. You can define it thus: |
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535 anything = ~eof |
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536 ## |
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537 |
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538 Character Sets |
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539 |
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540 This window lists all of the distinct �character set�s |
|
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541 which you defined, implicitly or explicitly, in your |
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|
542 �grammar�. Each line in the table describes one such |
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543 set. |
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544 |
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545 The description takes the form of the internal set |
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546 number and the defining �expression�. The �Auxiliary |
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547 Windows� menu will allow you to see the �Partition |
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548 Sets� which cover the character set, and the �Set |
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549 Elements� which it comprises, as well as the �Token Usage�. |
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550 ## |
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551 |
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552 Character Universe, Universe |
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553 |
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554 The character universe, or set of all expected input |
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555 characters to your parser, is defined as all characters |
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556 in the range given by a particular lower bound and a |
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557 particular upper bound, as described below. |
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558 |
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559 The character universe is used for two things in |
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560 AnaGram. The first use is for calculating the |
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561 �complement� of a character set. The second use is in |
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562 the input processing of your parser. Input characters |
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563 will be used to index a �token conversion� table to |
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564 convert character codes to token numbers. The length of |
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565 this table will be given by the size of the character |
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566 universe. If you have set the �test range� |
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567 �configuration switch� you parser will verify that the |
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568 input character is within the range of the conversion |
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569 table. Otherwise, the character code will not be |
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570 checked for validity. In this case, an out-of-range |
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571 character will lead to undefined behavior. |
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572 |
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573 If you have not used any characters with negative codes |
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574 in your grammar, the lower bound is zero. Otherwise, it |
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575 is the most negative such character. |
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576 |
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577 If the highest character code you have used is less |
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578 than or equal to 255, the upper bound will be 255. |
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579 |
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580 If you have used a character code greater than 255, the |
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581 upper bound will be the largest such code which appears |
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582 in your syntax file. |
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583 ## |
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584 |
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585 Characteristic Rule |
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586 |
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587 Each �parser state� is characterized by a particular |
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588 set of �grammar rules�, and for each such rule, a |
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589 marked token which is the next �token� expected. The |
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590 combination of a grammar rule and its marked token is often |
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591 called a �marked rule�. A marked rule which |
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592 characterizes a state is called a "characteristic |
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593 rule". In the course of doing �grammar analysis�, |
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594 AnaGram determines the characteristic rules for each |
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595 �parser state�. After analyzing your grammar, you may |
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596 inspect the �State Definition Table� to see the |
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597 characteristic rules for any state in your parser. |
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598 ## |
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599 |
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600 Characteristic Token |
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601 |
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602 Every state in a �parser�, except state 0, can be |
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603 characterized by the one, unique �token� which causes a |
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604 jump to that state. That token is called the |
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605 �characteristic token� of the state, because to get to |
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606 that �parser state� you must have just seen precisely |
|
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607 that token in the input. Note that several states could |
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608 have the same characteristic token. |
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609 |
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610 When you have a list of states, such as is given by the |
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611 �parser state stack�, it is equivalent to a list of |
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612 characteristic tokens. This list of tokens is the list |
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613 of tokens that have been recognized so far by the |
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614 parser. |
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615 ## |
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616 |
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617 Circular Definition |
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618 |
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619 If the �expansion rule�s for a �token� contain a �grammar rule� that |
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620 consists only of the token itself, the definition of the |
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621 token is circular. A circular definition is an extreme |
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622 case of �empty recursion�. |
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623 |
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624 As in cases of empty recursion, the generated parser may contain |
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625 infinite loops. When such a condition is detected, therefore, |
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626 �keyword anomaly� analysis the �File Trace� option are disabled. |
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627 |
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628 ## |
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629 |
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630 column |
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631 |
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632 "column" is an integer field in your �parser control |
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633 block� used for keeping track of the column number of |
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634 the current character in your input. Line and column |
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635 numbers are tracked only if the �lines and columns� |
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636 �configuration switch� has been set. |
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637 ## |
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638 |
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639 Command Line |
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640 |
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641 If you provide the name of a syntax file on the |
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642 command line when you start AnaGram, it will open |
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643 the file and run either �Analyze Grammar� or �Build |
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644 Parser� depending on the setting of the �Autobuild� |
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645 switch. |
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646 ## |
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647 |
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648 Command Line Version, agcl.exe |
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649 |
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650 The command line version of AnaGram, agcl.exe, can be |
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651 used in make files. It takes the name of a single syntax |
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652 file on the command |
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653 line. Error and �warning� messages are written to stdout. |
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654 |
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655 Normally you would only use the command line version once you |
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656 have finished developing your �parser� and are integrating |
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657 it with the rest of your program. |
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658 |
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659 The command line version of AnaGram is not included with |
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660 trial copies. |
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661 ## |
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662 |
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663 Comment |
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664 |
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665 You may incorporate comments in your syntax file using |
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666 either of two conventions. The first is the normal C |
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667 convention for comments which begin with "/*" and end |
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668 with "*/". Such comments may be of arbitrary length. By |
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669 setting or resetting the �nest comments� switch, you |
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670 may control whether they may be nested or not. |
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671 |
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672 The second convention for comments is the C++ comment |
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673 convention. In this case the comment begins with "//" |
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674 and ends with a newline. |
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675 |
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676 When writing a �grammar�, you may wish to allow a user |
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677 to comment his input freely without your having to |
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678 explicitly allow for comments in your grammar. You may |
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679 accomplish this by using the �disregard� statement. |
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|
680 ## |
|
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|
681 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
682 Compile Command |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
683 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
684 "Compile command" is a �configuration parameter� which |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
685 takes a string value. This parameter was used in the |
|
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Import AnaGram (near-)release tree into Mercurial.
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diff
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|
686 DOS version of AnaGram, but is ignored in the Windows |
|
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|
687 version. |
|
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|
688 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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parents:
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|
689 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
690 Complement |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
691 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
692 In set theory, the complement of a set, S, is the set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
693 of all elements of the �universe� which are not members |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
694 of the set S. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
695 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
696 In AnaGram, the complement operator for �character |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
697 sets� is given by '~' and has higher precedence than |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
698 �difference�, �intersection�, or �union�. |
|
13d2b8934445
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parents:
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|
699 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
700 In AnaGram, the most useful complement is that of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
701 end of file character set. For ordinary ascii files it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
702 is often convenient to read the entire file into |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
703 memory, append a zero byte to the end, and define the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
704 end of file set thus: |
|
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David A. Holland
parents:
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|
705 eof = 0 + ^Z. |
|
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David A. Holland
parents:
diff
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|
706 Then, ~�eof� represents all legitimate input characters. |
|
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David A. Holland
parents:
diff
changeset
|
707 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
708 You can then use set differences to specify certain |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
709 useful sets without tedious enumeration. For example, a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
710 comment that is to be terminated by the end of line |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
711 then consists of characters from the set |
|
13d2b8934445
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David A. Holland
parents:
diff
changeset
|
712 comment char = ~'\n' & ~eof |
|
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David A. Holland
parents:
diff
changeset
|
713 This set could also be written |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
714 comment char = ~('\n' + eof) |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
715 ## |
|
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David A. Holland
parents:
diff
changeset
|
716 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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parents:
diff
changeset
|
717 Completed Rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
718 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
719 A "completed rule" is a �characteristic rule� which has no �marked |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
720 token�. In other words, it has been completely matched and will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
721 reduced by the next input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
722 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
723 If there is more than one completed rule in a state, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
724 the decision as to which to reduce is made based on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
725 next input token. If there is only one completed rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
726 in a state, it will be reduced by default unless the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
727 �default reductions� switch has been reset, i.e., |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
728 turned off. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
729 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
730 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
731 Configuration File |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
732 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
733 If it can find them, AnaGram reads two configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
734 files to set up �configuration parameter�s. At program |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
735 initialization, it will first attempt to read a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
736 configuration file in the directory that contains |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
737 the AnaGram executable file you are running. Then it |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
738 will read a configuration file in your working |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
739 directory. Both files should have the name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
740 "AnaGram.cfg" if they exist. Neither is necessary. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
741 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
742 If a parameter is specified in both files, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
743 specification in the file from the working directory |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
744 takes precedence. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
745 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
746 The effect of this two stage process is to allow you to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
747 set your standard preferences in the principal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
748 directory, with specific overrides in your working |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
749 directories. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
750 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
751 The values for configuration parameters in �syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
752 files� override those read from configuration files. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
753 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
754 AnaGram does not save configuration parameters in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
755 the Windows registry, nor does it provide any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
756 mechanism for setting or changing the values of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
757 configuration parameters within AnaGram itself. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
758 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
759 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
760 Configuration Parameter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
761 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
762 Configuration parameters may be specified either in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
763 �configuration files� or in your �syntax file�. In your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
764 syntax files, configuration parameters are specified, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
765 one per line, in a �configuration section�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
766 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
767 AnaGram ignores case when identifying a configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
768 parameter, so that "ALLOW MACROS", "Allow Macros", and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
769 "allow macros" are all equivalent forms. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
770 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
771 There may be any number of configuration sections in a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
772 �syntax file�. Any parameter may be specified any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
773 number of times. Since AnaGram maintains only one value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
774 in storage for these parameters, whenever it refers to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
775 one it will see the most recently specified value. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
776 Every configuration parameter has a default value which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
777 has been chosen to correspond to a standard if it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
778 exists, customary usage if such can be determined, or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
779 otherwise to the most likely usage. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
780 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
781 Before executing an Analyze Grammar or Build Parser command, AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
782 resets configuration parameters to their initial values, as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
783 determined by the built in defaults and the configuration files read |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
784 at program initialization. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
785 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
786 The �Configuration Parameters Window� shows the current settings of all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
787 of the configuration parameters. When this window is active you may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
788 press �F1� or click with the �help cursor� to pop up a help window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
789 describing the parameter under the cursor bar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
790 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
791 There are several varieties of configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
792 parameters. Some simply set or reset a condition. These |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
793 need simply be stated to set the condition or negated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
794 with the tilde (~) to reset the condition. Thus |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
795 [ nest comments ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
796 causes AnaGram to allow nested comments, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
797 [ ~nest comments ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
798 causes AnaGram to disallow nested comments. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
799 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
800 If you prefer you may explicitly specify a switch value as on or off: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
801 [ nest comments = on] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
802 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
803 A second kind |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
804 of configuration parameter takes a value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
805 which is the name of a token. Thus |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
806 [ grammar token = c grammar] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
807 specifies that the token, c grammar, is the �grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
808 token� which is to be analyzed. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
809 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
810 A third variety of configuration parameter takes a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
811 value which is a C data type. Thus |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
812 [ default token type = unsigned char *] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
813 signifies that the �semantic value� of a token, unless |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
814 otherwise specified is a pointer to an unsigned char. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
815 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
816 A fourth variety of configuration parameter takes a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
817 string value to set some ascii string used by AnaGram. |
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818 Thus |
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|
819 [ header file name = "widget.h" ] |
|
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|
820 signifies that the header file created by AnaGram |
|
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|
821 should be called "widget.h". |
|
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|
822 |
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|
823 In string-valued parameters used to specify the names |
|
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Import AnaGram (near-)release tree into Mercurial.
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824 of output files or the name of your parser, you may use |
|
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825 the '#' character to indicate the name of your syntax |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
826 file: When the string is actually used, AnaGram will |
|
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|
827 substitute the syntax file name for the '#'. |
|
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|
828 |
|
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|
829 In string-valued parameters used to specify the names |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
830 of functions or variables that AnaGram generates, you |
|
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|
831 may use '$' to specify the name of your parser. When |
|
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parents:
diff
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|
832 the string is actually used, AnaGram will substitute |
|
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parents:
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|
833 the name of your parser for the '$'. |
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parents:
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|
834 |
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|
835 In the "�enum constant name�" configuration parameter |
|
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|
836 you may use '%' to specify where a token name is to be |
|
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parents:
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|
837 substituted. |
|
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parents:
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|
838 |
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parents:
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|
839 The final variety of configuration parameter takes a |
|
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parents:
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|
840 numeric value. The value may be decimal, octal |
|
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David A. Holland
parents:
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|
841 or hexadecimal, following the C conventions, and may |
|
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parents:
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|
842 have an optional sign. Thus |
|
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|
843 [parser stack size = 50] |
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844 tells AnaGram to allocate space for at least fifty stack entries |
|
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845 when it creates your parser. |
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|
846 ## |
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|
847 |
|
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|
848 Configuration Parameters Window |
|
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|
849 |
|
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|
850 The Configuration Parameters window lists the |
|
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|
851 �configuration parameter�s AnaGram accepts with their |
|
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852 current values, as set by the �configuration files� it |
|
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|
853 has read and by the most recent �syntax file� it has |
|
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|
854 analyzed. Configuration parameters cannot be changed |
|
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|
855 from within AnaGram. |
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856 ## |
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|
857 |
|
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|
858 Configuration Section |
|
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|
859 |
|
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|
860 A configuration section is one of the main divisions of |
|
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Import AnaGram (near-)release tree into Mercurial.
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861 your �syntax file�. It begins with a left square |
|
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|
862 bracket on a fresh line. It then contains definitions |
|
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|
863 of �configuration parameter�s, �configuration switch� |
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864 settings and �attribute statement�s. These |
|
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|
865 specifications must each start on a new line. The |
|
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|
866 configuration section is closed with a right bracket. |
|
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|
867 Any further component of your syntax file, other than a |
|
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868 �comment�, must start on a fresh line. |
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869 |
|
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|
870 There can be any number of configuration sections in a |
|
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|
871 syntax file. |
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872 ## |
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|
873 |
|
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|
874 Configuration Switch |
|
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|
875 |
|
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|
876 A configuration switch is a �configuration parameter� |
|
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|
877 which can take on only the two values true and false, |
|
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878 or on and off. You set a configuration switch, or turn |
|
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879 it on, by simply naming it in your �configuration file� |
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880 or in a �configuration section� of your �syntax file�. |
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881 You turn it off, or "reset" it, by use of the tilde: |
|
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882 "~nest comments", for example, resets, or turns off, |
|
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883 the �nest comments� switch. If you prefer, you may |
|
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|
884 assign the value "on" to set the switch, or "off" to |
|
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|
885 reset it. For example: |
|
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886 nest comments = on |
|
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|
887 ## |
|
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|
888 |
|
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|
889 Conflict |
|
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|
890 |
|
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891 "Conflicts" arise during the �grammar analysis� when |
|
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892 AnaGram cannot determine how to treat a given input |
|
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893 token. There are two sorts of conflicts: �shift-reduce |
|
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894 conflicts� and �reduce-reduce conflicts�. Conflicts may |
|
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|
895 arise either because the grammar is inherently |
|
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896 ambiguous, or simply because the grammar analyzer |
|
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|
897 cannot look far enough ahead to resolve the conflict. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
898 In the latter case, it is often possible to rewrite the |
|
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899 grammar in such a way as to eliminate the conflict. In |
|
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900 particular, �null productions� are a common source of |
|
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|
901 conflicts. |
|
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|
902 |
|
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|
903 When AnaGram analyzes your grammar, it lists all |
|
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|
904 unresolved conflicts in the �Conflicts� window. A number |
|
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|
905 of �Auxiliary Windows� available from the Conflicts window |
|
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|
906 provide help in identifying the source of the conflict. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
907 |
|
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|
908 There are a number of ways to deal with conflicts. If |
|
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|
909 you understand the conflict well, you may simply choose |
|
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|
910 to ignore it. When AnaGram encounters a shift-reduce |
|
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|
911 conflict while building parse tables it resolves it by |
|
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|
912 choosing the �shift action�. When AnaGram encounters a |
|
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|
913 reduce-reduce conflict while building parse tables, it |
|
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|
914 resolves it by selecting the �grammar rule� which |
|
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|
915 occurred first in the grammar. |
|
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|
916 |
|
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|
917 A second way to deal with conflicts is to set �operator |
|
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|
918 precedence� parameters. If you set these parameters, |
|
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|
919 AnaGram will use them preferentially to resolve |
|
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|
920 conflicts. Any conflicts so resolved will be listed in |
|
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|
921 the �Resolved Conflicts� window. |
|
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|
922 |
|
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|
923 A third way to resolve a conflict is to declare some |
|
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924 tokens as �sticky�. This is particularly useful for |
|
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|
925 �production�s whose sole purpose is to skip over |
|
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|
926 uninteresting input. |
|
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|
927 |
|
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|
928 A fourth way to resolve conflicts is to declare a token |
|
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|
929 to be a �subgrammar�. When you do this, AnaGram does |
|
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|
930 not look beyond the definition of the subgrammar token |
|
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|
931 itself for reducing tokens. This is not a particularly |
|
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|
932 selective way to resolve conflicts and should be used |
|
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|
933 only when the subgrammar token is naturally defined |
|
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|
934 only by internal criteria. The tokens identified by |
|
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|
935 lexical scanners are prime examples of this genre. |
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|
936 |
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|
937 The fifth way to deal with conflicts is to rewrite the |
|
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|
938 grammar to eliminate them. Many people prefer this |
|
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|
939 approach since it yields the highest level of |
|
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|
940 confidence in the resulting program. |
|
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|
941 |
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942 Please refer to the AnaGram User's Guide for more information about |
|
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943 dealing with conflicts. |
|
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944 ## |
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|
945 |
|
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|
946 Conflicts |
|
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|
947 |
|
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948 If there are �conflict�s in your grammar which are not |
|
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|
949 resolved by �precedence rules�, they will be listed in |
|
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|
950 the Conflicts window. The Conflicts window will also be |
|
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|
951 listed in the �Browse Menu�. Conflicts which have been |
|
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|
952 resolved by �precedence rules� are listed in the |
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953 �Resolved Conflicts� window. |
|
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954 |
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955 The Conflicts window lists the conflicts, or |
|
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956 ambiguities, which AnaGram found in your grammar. The |
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957 table identifies the �parser states� in which it found |
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958 conflicts, the �conflict token�s for which it had more |
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959 than one option, and the �marked rules� for each such |
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960 option. If one of the rules for a particular conflict |
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961 has a �marked token�, the conflict is |
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962 a �shift-reduce conflict�. The marked token is the token |
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963 to be shifted. If none of the rules has a marked token the conflict is |
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964 a �reduce-reduce conflict�. |
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965 |
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966 AnaGram provides a number of �Auxiliary Windows� to help |
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967 you find and fix the source of the conflict. The |
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968 �Conflict Trace� window is a pre-built �Grammar Trace� |
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969 window which shows you one of perhaps many ways to |
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970 encounter the conflict. The �Reduction Trace� window |
|
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971 shows the result of reducing a particular ambiguous |
|
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972 rule. |
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973 |
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974 In addition, the �Rule Derivation� and �Token |
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975 Derivation� windows show you why the conflict token is a |
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976 �reducing token�. They are particularly useful for |
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977 shift-reduce conflicts. |
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978 |
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979 The �Expansion Chain� window is helpful for understanding |
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980 reduce-reduce conflicts. |
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981 |
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982 Other Auxiliary Windows which are often useful are the |
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983 �State Definition� window, the �Reduction States� |
|
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984 window, and the �Problem States� window. |
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985 |
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986 Please refer to the AnaGram User's Guide for more information on how to |
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987 deal with conflicts. |
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988 ## |
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989 |
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990 Conflicts Resolved by Precedence Rules |
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991 |
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992 This �warning� message indicates that AnaGram has |
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993 resolved conflicts in your grammar by using �precedence |
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994 rules�: guidelines you supplied either by explicit |
|
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995 �precedence declarations�, by using a �sticky� |
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996 statement or �distinguish lexemes� statement, or |
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997 implicitly by using a �disregard� statement. These |
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998 conflicts are listed in the �Resolved Conflicts� |
|
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999 window, and are not listed in the �Conflicts� window. |
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1000 ## |
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1001 |
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1002 Conflict Token |
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1003 |
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1004 In any given �conflict�, there is a �token� for which |
|
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1005 an unambiguous �parser action� cannot be determined. |
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1006 This token is called the "conflict token". |
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1007 ## |
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1008 |
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1009 Conflict Trace |
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1010 |
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1011 The Conflict Trace is a ready-made �Grammar Trace� |
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1012 which shows you one of perhaps many ways to get to the |
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1013 state which has the �conflict� selected by the cursor |
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1014 bar. The Conflict Trace window is an option in the |
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1015 �Auxiliary Windows� menu for the �Conflicts� window and |
|
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1016 the �Resolved Conflicts� window. |
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1017 ## |
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1018 |
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1019 Const Data |
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1020 |
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1021 The const data �configuration switch� controls the use |
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1022 of CONST qualifiers in generated code. If the switch is |
|
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1023 set, all fixed data arrays in the �parser file� will be |
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1024 qualified as CONST, unless the �old style� switch is |
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1025 set. The default setting is ON. Other configuration |
|
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1026 switches which control declaration qualifiers in the |
|
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1027 parser file are �near functions� and �far tables�. |
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1028 ## |
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1029 |
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1030 CONTEXT |
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1031 |
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1032 "CONTEXT" is a macro which AnaGram defines for you if |
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1033 you have defined a �context type�. It provides access |
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1034 to the top value of the �context stack�. Your |
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1035 �GET_CONTEXT� macro may store the current context by |
|
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|
1036 assigning a value to CONTEXT. Suppose your parser uses |
|
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|
1037 �pointer input�, and you wish to know the value of the |
|
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|
1038 �pointer� for every production. You could define |
|
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|
1039 GET_CONTEXT thus: |
|
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1040 #define GET_CONTEXT CONTEXT = PCB.pointer |
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1041 |
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1042 In �reduction procedure�s, you may use the CONTEXT |
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1043 macro to find the context for the rule you are |
|
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|
1044 reducing, that is to say, the value the context |
|
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1045 variables had when the first token in the rule was |
|
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|
1046 encountered. |
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1047 ## |
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1048 |
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1049 Context Stack |
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1050 |
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1051 It is often convenient, when writing �reduction |
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1052 procedure�s, to know the actual context of the �grammar |
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1053 rule� your procedure is reducing. To do this you need |
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1054 to know the values that certain variables, such as |
|
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1055 stack pointers, or input pointers, in your program had |
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1056 at various stages as your parser matched the rule. You |
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1057 can accomplish this by maintaining a context stack. |
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1058 |
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1059 If you wish, AnaGram will keep track, on a stack, of any |
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1060 context variables you wish. To do so, define a structure |
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1061 which can hold all the values you need to stack. Use the |
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1062 �context type� �configuration parameter� to tell AnaGram |
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1063 how to declare the stack. Then define the �GET_CONTEXT� |
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1064 macro to gather the appropriate values and store them on |
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1065 the stack. The �CONTEXT� macro evaluates to the proper |
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1066 location into which the GET_CONTEXT macro should store |
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1067 the context value. AnaGram will invoke the GET_CONTEXT |
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1068 macro whenever necessary to make sure the right values |
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1069 are stacked. In a reduction procedure, you can then use |
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1070 the macro �RULE_CONTEXT� to find the value of the |
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1071 context structure as of the beginning of each token in |
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1072 the rule you are reducing. |
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1073 |
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1074 If your parser is �event driven�, store the context of |
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1075 the input token in PCB.input_context. The default |
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1076 version of GET_CONTEXT will stack the context as |
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1077 appropriate. |
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1078 |
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1079 If your parser should encounter an error, you may use |
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1080 �ERROR_CONTEXT� to determine the values of the context |
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1081 variables at the beginning of the aborted grammar rule. |
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1082 ## |
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1083 |
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1084 context type |
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1085 |
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1086 "Context type" is a �configuration parameter� whose |
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1087 value is a C type name, possibly as defined by a |
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1088 typedef statement. By default, "context type" is |
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1089 undefined. If you define it, AnaGram will set up a |
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1090 �context stack� in your �parser control block� so you |
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1091 can track the context of �production�s. |
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1092 |
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1093 Each time your parser pushes values onto the state |
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1094 stack and value stack it will invoke the �GET_CONTEXT� |
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1095 macro to store the current context on the context |
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1096 stack. The macro �CONTEXT� names the current stack |
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1097 location. In your GET_CONTEXT macro you can use it as |
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1098 the destination for the current context. In a |
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1099 �reduction procedure�, CONTEXT names the context as of |
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1100 the beginning of the production. Two other macros are |
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1101 available to inspect the values of the context stack. |
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1102 In a reduction procedure, you may use �RULE_CONTEXT�[k] |
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1103 to determine the value of the context variable as it |
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1104 was as of the (k+1)th token in the rule. In particular, |
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1105 RULE_CONTEXT[0] is the value the context variable had |
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1106 when the first token in the rule was seen. |
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1107 |
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1108 If you enable the �error frame� �configuration switch�, |
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1109 you may use �ERROR_CONTEXT� to determine the context of |
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1110 the production your parser was trying to identify at |
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1111 the time of the error. |
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1112 ## |
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1113 |
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1114 CONVERT_CASE |
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1115 |
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1116 CONVERT_CASE is a user definable macro which AnaGram |
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1117 invokes to convert the case of input characters when |
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1118 the �case sensitive� switch has been turned off. If |
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1119 you do not define the macro yourself, AnaGram will |
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1120 provide a macro which will convert case correctly |
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1121 for characters in the ASCII character range and |
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1122 also for �ISO latin 1� characters if the corresponding |
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1123 �configuration switch� is on. |
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1124 |
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1125 ## |
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1126 |
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1127 Coverage File Name |
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1128 |
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1129 If you have set the �rule coverage� �configuration |
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1130 switch� to include coverage analysis in your parser, |
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1131 AnaGram uses the value of the coverage file name |
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1132 �configuration parameter� to find the results of your |
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1133 testing. The value of the parameter is a string. The |
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1134 default value is "#.nrc", where '#' represents the name |
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1135 of your syntax file. |
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1136 ## |
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1137 |
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1138 cs |
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1139 |
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1140 cs is a field in a �parser control block� which |
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1141 contains your �context stack�. cs will be defined only |
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1142 if you have defined the �configuration parameter� |
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1143 �context type�. |
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1144 ## |
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1145 |
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1146 Current Grammar |
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1147 |
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1148 The Current Grammar is the �grammar� you presently have |
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1149 loaded. Its name is displayed on the title bar of |
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1150 each AnaGram window. |
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1151 |
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1152 A status field at the right center of the �Control Panel� |
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1153 indicates the state of processing that has been |
|
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1154 carried out on the grammar. |
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1155 |
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1156 "Loaded" means that the �syntax file� has been read |
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1157 into memory, but that syntax errors have been found. |
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1158 |
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1159 "Parsed" means that AnaGram has tried to analyze the |
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1160 grammar, but got into some kind of difficulty and did |
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1161 not complete the job. The explanation should be |
|
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1162 apparent from the messages in the �Warnings� window. |
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1163 |
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1164 "Analyzed" means that a �grammar analysis� has been |
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1165 completed, but no �output files� have been written. |
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1166 |
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1167 "Built" means that an analysis has been completed and |
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1168 output files have been written. |
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1169 ## |
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1170 |
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1171 Data Type |
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1172 |
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1173 The �tokens� in your �parser� usually have �semantic |
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1174 values�. The data types for these values will be |
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1175 determined by the �default input type� and �default |
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1176 token type� �configuration parameter�s unless you |
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1177 explicitly provide �token declarations� in your grammar. |
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1178 You may also define the data type for any �nonterminal� |
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1179 token by preceding the token name with an ordinary C |
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1180 cast when you write a production. For example: |
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1181 |
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1182 (int) integer |
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1183 -> '0-9':d =d-'0'; |
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1184 -> integer:n, '0-9':d =10*n + d - '0'; |
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1185 |
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1186 The data type may be any simple C or C++ data type, with |
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1187 arbitrary indirection and qualification. You may also |
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1188 use any type you have defined by means of typedef, |
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1189 struct or class definitions. Template classes may also |
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1190 be used. If you specify a type of your own definition, |
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1191 you must provide a definition in the �C prologue� at the |
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1192 beginning of your �syntax file�. |
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1193 |
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1194 A token may have the type "void" if its value has no |
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1195 interest for the parser. Since your parser will not |
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1196 stack a value for a void token, your parser may run |
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1197 somewhat faster when tokens are declared as void. |
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1198 ## |
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1199 |
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1200 Declare pcb |
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1201 |
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1202 "Declare pcb" is a �configuration switch� that defaults |
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1203 to on. If this switch is set when you invoke the �Build |
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1204 Parser� command, AnaGram will automatically declare a |
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1205 �parser control block� for you, at the beginning of |
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1206 your parser file. If you have used data types that you |
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1207 define yourself, the typedef statements need to precede |
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1208 the parser control block declaration. In this case, you |
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1209 should turn "declare pcb" off and declare it yourself. |
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1210 |
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1211 For more information, see the AnaGram User's Guide. |
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1212 ## |
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1213 |
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1214 Default Input Type |
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1215 |
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1216 The default input type is a �configuration parameter� |
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1217 which determines the �data type� for the �semantic |
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1218 value�s of �terminal tokens� if they are not explicitly |
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|
1219 declared. Normally, you would explicitly declare |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1220 terminal tokens only when you have set the �input |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1221 values� �configuration switch�. If you do not set the |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1222 default input type, it will default to "int". |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1223 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1224 The default data type for the values of �nonterminal |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1225 tokens� is given by the �default token type� |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1226 configuration parameter. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1227 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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1228 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1229 Default Reduction |
|
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Import AnaGram (near-)release tree into Mercurial.
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1230 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1231 "Default reductions" is a �configuration switch� which |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1232 defaults to on. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1233 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1234 A "default reduction" is a �parser action� which may be |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1235 used in your parser in any state which has precisely |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1236 one �completed rule�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1237 |
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13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1238 If a given �parser state� has, among its �characteristic |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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parents:
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|
1239 rules�, exactly one completed rule, it is usually faster |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1240 to reduce it on any input than to check specifically for |
|
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Import AnaGram (near-)release tree into Mercurial.
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1241 correct input before reducing it. The only time this |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1242 default reduction causes trouble is in the event of a |
|
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Import AnaGram (near-)release tree into Mercurial.
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1243 �syntax error�. In this situation you may get an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1244 erroneous reduction. Normally when you are parsing a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1245 file, this is inconsequential because you are not going |
|
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Import AnaGram (near-)release tree into Mercurial.
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1246 to continue semantic action in the presence of error. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1247 But, if you are using your parser to handle real-time |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1248 interactive input, you have to be able to continue |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1249 semantic processing after notifying your user that he |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1250 has entered erroneous input. In this case you would want |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1251 default reductions to have been turned off so that |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1252 �production�s are reduced only when there is correct |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1253 input. |
|
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1254 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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1255 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1256 Default reduction value |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1257 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1258 If a �grammar rule� does not have a �reduction procedure� |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1259 the �semantic value� of the first token in the rule will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1260 be taken as the semantic value of the token on the left |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1261 hand side. If these tokens do not have the same �data type� |
|
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1262 a �warning� will be given. |
|
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|
1263 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1264 |
|
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|
1265 Default Token Type |
|
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Import AnaGram (near-)release tree into Mercurial.
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1266 |
|
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|
1267 "Default token type" is a �configuration parameter� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1268 which determines the �data type� for the �semantic |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1269 value� of a �nonterminal token� if no other type is |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1270 explicitly specified. It defaults to void. Therefore, if |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1271 any �reduction procedure� returns a value, you must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1272 either explicitly set the type of the �reduction token� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1273 or you must set default token type to an appropriate |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1274 value. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1275 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1276 The default token type cannot have a �wrapper� class |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1277 defined. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1278 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1279 The default data type for the value of a �terminal |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1280 token� is given by the �default input type� |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1281 configuration parameter. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1282 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1283 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1284 Definition, Definition Statement |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1285 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1286 AnaGram syntax files may contain definition statements |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1287 which assign new names to �character sets�, �virtual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1288 productions�, �keyword strings�, �immediate actions�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1289 or �tokens�. Definitions have the form |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1290 name = <character set> |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1291 name = <virtual production> |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1292 name = <keyword string> |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1293 name = <immediate action> |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1294 name = <token name> |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1295 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1296 For example, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1297 letter = 'a-z' + 'A-Z' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1298 statement list = statement?... |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1299 include = "include" |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1300 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1301 The symbols thus defined may be used anywhere the |
|
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Import AnaGram (near-)release tree into Mercurial.
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parents:
diff
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|
1302 expression on the right hand side might be used. Such |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1303 definitions, in and of themselves, do not define tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1304 Tokens are defined only by their usage in productions. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1305 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1306 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1307 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1308 DELETE_WRAPPERS |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1309 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1310 If your parser uses �wrapper�s and exits with an error condition, there |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1311 may be objects remaining on the �parser value stack�. The DELETE_WRAPPERS macro |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1312 can be used to delete any remaining objects on the stack. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1313 If you have enabled |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1314 �auto resynch�, DELETE_WRAPPERS will be invoked automatically. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1315 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1316 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1317 Diagnose Errors |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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diff
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|
1318 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1319 "Diagnose errors" is a �configuration switch� which |
|
13d2b8934445
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|
1320 defaults to on. When this switch is on, AnaGram includes a |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1321 function, ag_diagnose(), in your parser which provides simple |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1322 syntax error disgnoses. When your parser encounters a |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1323 syntax error, this function will be called immediately prior |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1324 to the invocation of the �SYNTAX_ERROR� macro. A pointer to the message will be |
|
13d2b8934445
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|
1325 stored in the �error_message� field of the �parser control block�. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1326 |
|
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|
1327 If you wish to implement your own �error diagnosis�, you |
|
13d2b8934445
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|
1328 should turn this switch off, and include a call to your |
|
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|
1329 own diagnostic procedure in your SYNTAX_ERROR macro. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1330 |
|
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|
1331 ag_diagnose() provides three possible error messages, |
|
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|
1332 governed by three macros: �MISSING_FORMAT�, �UNEXPECTED_FORMAT�, and |
|
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|
1333 �UNNAMED_TOKEN�. You may override the definitions of |
|
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|
1334 these macros with your own definitions if you wish |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1335 to provide diagnostics in another language |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1336 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1337 If you have set the �error frame� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1338 switch it will also set the �error_frame_token� field. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1339 The "error_frame_token" is the non-terminal token which |
|
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|
1340 the parser was trying to complete when the error was |
|
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|
1341 encountered. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1342 |
|
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|
1343 When the "diagnose errors" switch is set, AnaGram also |
|
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|
1344 includes the a �token names� table in the parser which |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1345 contains the ascii names of the tokens in the grammar, |
|
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|
1346 including entries for character constants and keywords. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1347 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1348 Use the �token names only� switch to limit the table |
|
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|
1349 to explicitly named tokens only. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1350 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1351 |
|
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|
1352 MISSING_FORMAT |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1353 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1354 MISSING_FORMAT is a macro that is used by the error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1355 diagnositic function created by the �diagnose errors� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1356 switch. If you do not define it in your parser, |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1357 AnaGram will define it thus: |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1358 #define MISSING_FORMAT "Missing %s" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1359 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1360 This format is used when the diagnostic function can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1361 identify a unique terminal or nonterminal token that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1362 would satisfy the syntactic rules and is named |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1363 in the �token names� table. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1364 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1365 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1366 UNEXPECTED_FORMAT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1367 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1368 UNEXPECTED_FORMAT is a macro that is used by the error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1369 diagnositic function created by the �diagnose errors� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1370 switch. If you do not define it in your parser, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1371 AnaGram will define it thus: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1372 #define UNEXPECTED_FORMAT "Unexpected %s" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1373 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1374 This format is used when the diagnostic function cannot |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1375 identify a named, unique terminal or nonterminal token that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1376 would satisfy the syntactic rules and finds an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1377 incorrect token, the name of which can be found |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1378 in the �token names� table. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1379 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1380 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1381 UNNAMED_TOKEN |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1382 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1383 UNNAMED_TOKEN is a macro that is used by the error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1384 diagnositic function created by the �diagnose errors� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1385 switch. If you do not define it in your parser, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1386 AnaGram will define it thus: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1387 #define UNNAMED_TOKEN "input" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1388 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1389 This macro is used as argument for the �UNEXPECTED_FORMAT� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1390 macro when the actual, erroneous input cannot be identified. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1391 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1392 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1393 Difference |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1394 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1395 In set theory, the difference of two sets, A and B, is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1396 defined to be the set of all elements of A that are not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1397 elements of B. In an AnaGram �syntax file�, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1398 represent the difference of two �character sets� by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1399 using the '-' operator. Thus the difference of A and B |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1400 is A - B. The difference operator is �left |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1401 associative�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1402 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1403 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1404 Disregard |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1405 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1406 The purpose of the "disregard" statement is to skip over |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1407 uninteresting �white space� and comments in your input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1408 file. It allows you to specify a token that should be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1409 passed over in the input to your parser. The statement |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1410 takes the form: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1411 disregard ws |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1412 where "ws" is a token name or character set. Disregard |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1413 statements, like other �attribute statement�s, may be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1414 placed in any �configuration section�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1415 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1416 You may have more than one disregard statement in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1417 �grammar�. If you do, AnaGram will create a shell |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1418 production. For example, suppose you write: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1419 [ disregard alpha |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1420 disregard beta ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1421 AnaGram will proceed as though you had written: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1422 gamma -> alpha | beta |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1423 [ disregard gamma ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1424 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1425 It frequently happens that you wish your �parser� to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1426 disregard blanks or comments, except that �white space� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1427 within names, numbers, strings, and other elementary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1428 constructs is subject to special rules and thus should |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1429 not be disregarded blindly. In this case, you can use |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1430 the "�lexeme�" statement to declare these constructs off |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1431 limits for the disregard statement. Within these |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1432 constructs, the disregard statement will be inoperative |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1433 and the admissibility of white space is determined |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1434 solely by the productions which define these constructs. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1435 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1436 Outside those productions which define lexemes, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1437 should not generally use a token which is supposed to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1438 disregarded. If you do, your grammar will have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1439 �conflict�s, since the token could satisfy both the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1440 explicit usage, as well as the implicit rules set up by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1441 the disregard statement. Such conflicts, however, are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1442 resolved automatically in favor of your explicit use of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1443 the token. The conflicts will appear in the �Resolved |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1444 Conflicts� window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1445 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1446 If you have "open ended" lexemes in your grammar such |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1447 as variable names or numeric constants, your grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1448 will detect a conflict if one of these lexemes may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1449 follow another such lexeme immediately. To deal with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1450 these conflicts, you should turn on the "�Distinguish |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1451 Lexemes�" configuration switch. It will cause white |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1452 space to be required as a separator between the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1453 lexemes. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1454 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1455 In order to implement the "disregard" statement AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1456 will redefine some tokens in your grammar. For example, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1457 '+' may be redefined to consist of a simple plus sign |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1458 followed by optional white space: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1459 '+' -> '+'%, white space?... |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1460 The �percent sign� is used to indicate the original, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1461 simple plus without the optional white space attached. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1462 You will probably notice the percent sign appearing in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1463 some windows and traces. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1464 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1465 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1466 distinguish keywords |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1467 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1468 "distinguish keywords" is an �attribute statement� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1469 which you may include in a �configuration section�. It |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1470 is used to tell AnaGram how to distinguish �keyword�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1471 from similar sequences of characters in your input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1472 stream. For example, you may want your parser to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1473 recognize "int" as a keyword when it appears in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1474 following context: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1475 int x; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1476 but not when in appears in the middle of such words as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1477 "integral" and "intolerant". The operand of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1478 "distinguish keywords" is a list of character set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1479 �expression�s separated by commas and enclosed in braces |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1480 ({ }). |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1481 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1482 Once AnaGram has read your entire syntax file, it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1483 evaluates all of these character sets and tests each |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1484 keyword string against the character sets in the order |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1485 in which they were encountered in the program. If all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1486 the characters which constitute a particular keyword |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1487 are members of the specified set, the keyword logic is |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1488 set up so that it will recognize the keyword only if |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1489 the immediately following character is not in the set. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1490 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1491 In the example above, |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1492 [distinguish keywords {'a-z'} ] |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1493 will do the trick. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1494 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1495 The "�sticky�" statement also affects the recognition |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1496 of keywords. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1497 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1498 |
|
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Import AnaGram (near-)release tree into Mercurial.
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parents:
diff
changeset
|
1499 Distinguish Lexemes |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1500 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1501 The "distinguish lexemes" �configuration switch� is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1502 used in conjunction with the "�disregard�" statement |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1503 and the "�lexeme�" statement to resolve the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1504 �shift-reduce conflict�s which often crop up when |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1505 suppressing white space. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1506 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1507 The difficulty with suppressing white space is that you |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1508 wish it to be optional in cases like "x+y", where it is |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1509 not necessary in order to parse correctly, but you want |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1510 to require it in situations such as "mytype x", where |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1511 it is necessary to separate otherwise indistinguishable |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1512 constructs. If the white space were optional, it would |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1513 be necessary to allow for "mytypex", but it would be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1514 impossible to determine if this were to be interpreted as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1515 "mytype x", "mytyp ex", or any of the many other |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1516 possibilities. |
|
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Import AnaGram (near-)release tree into Mercurial.
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parents:
diff
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|
1517 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1518 The distinguish lexemes switch causes AnaGram to make |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1519 the white space optional where doing so causes no |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1520 ambiguity and makes it mandatory where to make it |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1521 optional would lead to ambiguity. In the example given |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1522 above, "mytypex" would be treated as a single name, and |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1523 another name would have to follow separating white |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1524 space. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1525 |
|
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David A. Holland
parents:
diff
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|
1526 The default value for distinguish lexemes is OFF. It is |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1527 anticipated that this will be changed to ON in future |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1528 releases of AnaGram. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1529 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1530 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1531 Duplicate Production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1532 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1533 This �warning� message appears when a �production� |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
1534 appears twice in your �grammar�. You will have a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1535 number of �reduce-reduce conflict�s as a consequence. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1536 Eliminate the duplicate, and the conflicts it caused |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1537 will go away. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1538 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1539 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1540 Edit Command |
|
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Import AnaGram (near-)release tree into Mercurial.
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parents:
diff
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|
1541 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1542 "Edit command" is a �configuration parameter� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1543 accepts a string value. It is no longer used and is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1544 retained only for file compatiblity with the DOS |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1545 version of AnaGram. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1546 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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changeset
|
1547 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1548 Embedded C |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1549 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1550 You may encapsulate pieces of C or C++ code in your �syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1551 file� more or less arbitrarily. Such pieces of code will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1552 simply be copied to the �parser file� in the order in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1553 which they are encountered. Each such piece of code must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1554 be enclosed with braces({}). The left brace must be on a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1555 new line, and nothing except comments may follow the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1556 right brace. AnaGram does not inspect the interior of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1557 such a piece of C code except to identify character |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1558 constants, strings, comments and blocks surrounded with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1559 braces so that it does not identify the end of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1560 embedded C prematurely. Note that AnaGram will use the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1561 status of the �nest comments� �configuration switch� in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1562 effect at the beginning of the embedded C. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1563 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1564 AnaGram, of course, can be confused by unterminated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1565 strings, unbalanced brackets, and unterminated comments. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1566 The most likely outcome, in such a situation, is that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1567 AnaGram will encounter an end of file looking for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1568 end of the embedded C. Should this happen, AnaGram will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1569 identify the beginning of the piece of embedded C which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1570 caused the problem. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1571 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1572 If your syntax file begins with a block of embedded C, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1573 called the "�C prologue�", it will be copied to the very |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1574 beginning of the parser file, preceding all of AnaGram's |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1575 output. You may use such an initial block of embedded C |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1576 to guarantee that program title comments, copyright |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1577 notices and important definitions are at the very |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1578 beginning of your parser file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1579 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1580 The code you include as embedded C, of course, has to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1581 coexist with the code AnaGram generates. In order to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1582 keep the potential for name conflicts to a minimum, all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1583 variables and functions which AnaGram defines begin with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1584 the letters "ag_". You should avoid variable names which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1585 begin with these letters. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1586 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1587 If AnaGram finds no embedded C in a syntax file, and you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1588 ask it to build a parser, it will automatically generate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1589 a main program that calls your parser. If you don't want |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1590 it to do this, you may turn off the �main program� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1591 �configuration switch�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1592 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1593 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1594 Empty Keyword String |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1595 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1596 This �warning� appears when you have a keyword string |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1597 that contains no characters whatsoever. �Keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1598 strings� must contain at least one character. If you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1599 wish a null match, use a �null production� instead. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1600 ## |
|
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David A. Holland
parents:
diff
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|
1601 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1602 Enable Mouse |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1603 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1604 "Enable mouse" is a �configuration switch� that defaults |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1605 to on. It is not used in the Windows version of AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1606 and has been retained only for file compatibility with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1607 the DOS version. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1608 ## |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
1609 |
|
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David A. Holland
parents:
diff
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|
1610 Enum Constant Name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1611 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1612 The "enum constant name" �configuration parameter� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
1613 allows you to select the name AnaGram will use for the |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
1614 set of enumeration constants it defines in the �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1615 header� file for your �parser�. The value of "enum |
|
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David A. Holland
parents:
diff
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|
1616 constant name" should be a string containing the '%' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1617 character. AnaGram will substitute each token name in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1618 turn into this template as it creates the list of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1619 enumeration constants. If it finds a '$' character it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
1620 will substitute the name of your parser. The default |
|
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1621 value of "enum constant name" is "$_%_token". |
|
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1622 ## |
|
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1623 |
|
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|
1624 Enumeration Constants |
|
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1625 |
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|
1626 In your �parser header� file, AnaGram includes a typedef |
|
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|
1627 enum statement which provides enumeration constants |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1628 corresponding to all the named constants in your |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1629 grammar. The names of the enumeration constants |
|
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|
1630 themselves are defined by the �enum constant name� |
|
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|
1631 �configuration parameter�. These constants are useful |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1632 when dealing with �semantically determined productions�. |
|
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|
1633 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1634 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1635 Enum |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1636 |
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1637 Within a �configuration section�, you may use an "enum" |
|
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1638 statement to define numeric values for any number of |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1639 tokens just as you define enumeration constants in C. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1640 The syntax is effectively the same as the enum statement |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1641 in C: |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1642 |
|
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|
1643 [ |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1644 enum { |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1645 first = 60, |
|
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|
1646 second, |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1647 third, |
|
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1648 fourth = 'a', |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1649 fifth, |
|
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1650 } |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1651 ] |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1652 |
|
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1653 is exactly equivalent to |
|
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1654 first = 60 |
|
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1655 second = 61 |
|
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|
1656 third = 62 |
|
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1657 fourth = 'a' |
|
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1658 fifth = 'b' |
|
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1659 ## |
|
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|
1660 |
|
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1661 eof |
|
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|
1662 |
|
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|
1663 "eof" is a quasi reserved word in AnaGram, used to |
|
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1664 specify an end of file token. You may use another token |
|
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1665 as an end of file delimiter by setting the �Eof Token� |
|
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1666 �configuration parameter�. eof is not required unless |
|
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1667 you use �automatic resynchronization� in your �parser�. |
|
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|
1668 |
|
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1669 If you have not defined eof or specified an Eof Token |
|
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|
1670 parameter, �File Trace� may show a syntax error when it |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1671 encounters the end of a test file. |
|
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|
1672 |
|
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|
1673 There are various ascii values that are commonly used |
|
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Import AnaGram (near-)release tree into Mercurial.
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1674 to represent an end of file. The end of a string in |
|
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1675 memory is commonly 0, DOS uses ^Z, Unix uses ^D, and |
|
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1676 Unix style stream I/O uses -1. It is often convenient |
|
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1677 then to define |
|
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|
1678 |
|
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|
1679 eof = -1 + 0 + ^D + ^Z |
|
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|
1680 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1681 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1682 Eof Token |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1683 |
|
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|
1684 "Eof token" is a �configuration parameter� which accepts |
|
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Import AnaGram (near-)release tree into Mercurial.
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1685 a token name as a value. There is no default value. |
|
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1686 AnaGram does not need a specification for the eof token |
|
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|
1687 unless you are using its �automatic resynchronization� |
|
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|
1688 facility. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1689 |
|
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|
1690 If you use the �automatic resynchronization� capability |
|
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1691 of AnaGram, you must specify explicitly an end of file |
|
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1692 token. You can do this either by defining a �terminal |
|
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Import AnaGram (near-)release tree into Mercurial.
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1693 token� in your �grammar� called eof or by using the "eof |
|
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|
1694 token" parameter to identify some other terminal token |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1695 to be used as the end of file marker. You would do this |
|
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|
1696 only if you must use the name "�eof�" for some other |
|
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|
1697 purpose. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1698 |
|
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|
1699 Note that "eof" is case sensitive. Neither Eof nor |
|
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|
1700 EOF will qualify as end of file tokens unless you |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1701 explicitly specify them using the eof token parameter. |
|
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|
1702 ## |
|
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|
1703 |
|
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|
1704 Eof Token Not Defined |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1705 |
|
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|
1706 This �warning� appears if you have requested either |
|
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|
1707 �error token resynchronization� or �automatic |
|
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David A. Holland
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|
1708 resynchronization� and you have not defined an �eof |
|
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|
1709 token�. The resynchronization procedure will not work |
|
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|
1710 correctly at end of file. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1711 ## |
|
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|
1712 |
|
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|
1713 Error Action |
|
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|
1714 |
|
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|
1715 The error action is one of the four �parser action�s of a |
|
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|
1716 traditional �parsing engine�. The error action is |
|
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|
1717 performed when the parser has encountered an input |
|
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|
1718 token which is not admissible in the current state. |
|
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|
1719 The further behavior of a traditional parser is |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1720 undefined. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1721 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1722 |
|
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|
1723 Error Defining |
|
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|
1724 |
|
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|
1725 "Error defining TXXX: <token representation>" is a |
|
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|
1726 �warning� message which appears if errors are encountered |
|
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|
1727 while attempting to evaluate the �character set� for |
|
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|
1728 the specified �token�. This warning is always generated |
|
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|
1729 in addition to more detailed warnings that are made |
|
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|
1730 when the actual errors are encountered. |
|
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|
1731 ## |
|
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|
1732 |
|
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|
1733 Error frame |
|
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|
1734 |
|
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|
1735 "Error frame" is a �configuration switch� which defaults |
|
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|
1736 to off. You use this switch to specify the �error |
|
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|
1737 diagnosis� capabilities of your parser. If this switch |
|
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|
1738 is set and the �diagnose errors� switch is set, i.e., |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1739 on, your parser will include a function which will |
|
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|
1740 determine the "context" of any �syntax error�, that is, |
|
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|
1741 the token the parser was trying to complete. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1742 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1743 To determine the context of an error, your parser will |
|
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|
1744 scan backwards through the �parser state stack�, |
|
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|
1745 examining �characteristic rules� until it finds a state |
|
13d2b8934445
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|
1746 which can accept a unique �nonterminal� reduction token |
|
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|
1747 that you have not marked as �hidden�. It will then set |
|
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|
1748 PCB.�error_frame_ssx� to the �parser stack index� for |
|
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|
1749 that level. |
|
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|
1750 ## |
|
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|
1751 |
|
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|
1752 ERROR_CONTEXT |
|
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|
1753 |
|
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|
1754 ERROR_CONTEXT is a macro AnaGram defines for you. If |
|
13d2b8934445
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David A. Holland
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|
1755 your parser encounters a �syntax error�, you have |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1756 enabled the �error frame� �configuration switch�, and |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1757 you have defined a �context type�, ERROR_CONTEXT will |
|
13d2b8934445
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David A. Holland
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diff
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|
1758 enable you to access the �context� as of when the parser |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1759 encountered the beginning of the �error_frame_token�. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1760 ## |
|
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|
1761 |
|
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|
1762 Error Diagnosis |
|
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|
1763 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1764 "Error diagnosis" and �error recovery� are the two |
|
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David A. Holland
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|
1765 aspects of �error handling�. If in the �embedded C� |
|
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David A. Holland
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|
1766 portion of your syntax file you define a macro called |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1767 �SYNTAX_ERROR�, it will be invoked by the parser when a |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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1768 �syntax error� is encountered. If you have set the |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1769 �diagnose errors� �configuration switch�, the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1770 �error_message� field of the �parser control block� will |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1771 contain a pointer to a string containing a diagnostic |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1772 message. The diagnostic is of the form "Missing <token |
|
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David A. Holland
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|
1773 name>" or "Unexpected <token name>". |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1774 |
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Import AnaGram (near-)release tree into Mercurial.
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|
1775 If you do not define SYNTAX_ERROR it will be |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1776 automatically defined so that a message will be written |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1777 to stderr. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1778 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1779 If the �lines and columns� switch has been set you will |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1780 have the current line number and column number available |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1781 for your diagnostic message. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1782 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1783 If you have set the �error frame� switch as well as the |
|
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David A. Holland
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|
1784 diagnose errors switch, the variable |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1785 PCB.�error_frame_token� will identify the �nonterminal |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1786 token� the parser was trying to recognize when the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1787 error was encountered. |
|
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David A. Holland
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|
1788 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1789 Of course, if your parser is controlling direct keyboard |
|
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David A. Holland
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diff
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|
1790 input, a diagnosis might be unnecessary. In this case |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1791 you might define SYNTAX_ERROR so that it simply beeps at |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1792 the user and let it go at that. |
|
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|
1793 ## |
|
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|
1794 |
|
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David A. Holland
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|
1795 Error Handling |
|
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|
1796 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1797 Rarely is a parser built to read an arbitrary input |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1798 file. The normal situation is that the parser is built |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
1799 to read files that conform to the rules specified in a |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1800 grammar, rules that describe a class of input files |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1801 rather than all possible input files. If the input file |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1802 does not conform to the grammar, the parser will detect |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1803 a �syntax error�. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1804 |
|
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|
1805 There are two aspects to error handling in your parser: |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1806 �error diagnosis� and �error recovery�. Error diagnosis |
|
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|
1807 consists in informing your user that something |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1808 unexpected has happened. Error recovery consists in |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1809 either aborting the parse, or getting it started again |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1810 in some reasonable manner. AnaGram provides several |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1811 options for both error diagnosis and error recovery. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1812 |
|
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|
1813 When a syntax error is encountered, first your error |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1814 diagnosis option is executed and then your error |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1815 recovery option is executed. |
|
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|
1816 ## |
|
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|
1817 |
|
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|
1818 error_message |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1819 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1820 error_message is a field in a �parser control block� to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1821 which your �error handling� procedures may refer. If you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
1822 have set the �diagnose errors� �configuration switch�, |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1823 on encountering a �syntax error� your �parser� will |
|
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|
1824 create a string containing an appropriate diagnostic |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1825 message and store a pointer to it into |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1826 PCB.error_message. |
|
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|
1827 ## |
|
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|
1828 |
|
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|
1829 Error Trace |
|
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|
1830 |
|
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|
1831 "Error Trace" is both a �configuration switch� and the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1832 name of an option in the �Action Menu�. If the switch |
|
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David A. Holland
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|
1833 is on, AnaGram adds code to your parser to capture |
|
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|
1834 state information to a file in case of a �syntax error�. The Error |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1835 Trace option can then read this information and prepare a pre-built |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1836 �Grammar Trace� showing you the state of the parser at the time of |
|
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Import AnaGram (near-)release tree into Mercurial.
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diff
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|
1837 the error. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1838 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1839 The name of the file is determined by the macro |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1840 �AG_TRACE_FILE_NAME�. AnaGram will provide a default |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1841 definition for the macro consisting of the name of |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1842 your �syntax file� plus the extension ".etr". You |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1843 may override this definition by defining AG_TRACE_FILE_NAME |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1844 in your �embedded C�. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1845 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1846 If error trace is enabled, AnaGram will also enable the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1847 Error Trace option on the �Action Menu�. If you select |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1848 Error Trace AnaGram will initialize a �Grammar Trace� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1849 window from the error trace file you select. The parser |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1850 stack of the trace will be as it was when the error |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1851 occurred. The last line of the parser stack pane will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
1852 show the �lookahead token� that caused the syntax error. You may |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1853 then use the Grammar Trace to explore the nature of |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1854 the syntax error your parser encountered. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
1855 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1856 AnaGram will |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1857 warn you if the error trace file is older than |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1858 the syntax file, since under those conditions, the |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1859 error trace file might be invalid. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1860 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1861 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1862 AG_TRACE_FILE_NAME |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1863 |
|
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|
1864 AG_TRACE_FILE_NAME is a C macro used to determine the |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1865 name of the file your parser will write when it |
|
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|
1866 encounters a �syntax error� if you have enabled |
|
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|
1867 the �error trace� �configuration switch�. |
|
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|
1868 |
|
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|
1869 You may define AG_TRACE_FILE_NAME in your �embedded C�. |
|
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|
1870 AnaGram provides a default definition given by the |
|
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|
1871 name of your �syntax file� with the extension ".etr". |
|
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|
1872 ## |
|
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|
1873 |
|
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|
1874 Error Recovery |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1875 |
|
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|
1876 Error recovery is the process of continuing after a |
|
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|
1877 �syntax error�. AnaGram offers several options. These |
|
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|
1878 are controlled by �configuration parameter�s and by |
|
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|
1879 your grammar. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
1880 |
|
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|
1881 If you do not specify any error recovery, your parser |
|
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|
1882 will simply return to the calling program when it |
|
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|
1883 encounters a syntax error. �PCB�.�exit_flag� will be set |
|
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|
1884 to two, to indicate termination on syntax error. |
|
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|
1885 |
|
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|
1886 If you wish your parser to simply ignore the erroneous |
|
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|
1887 token and continue, set PCB.exit_flag to zero in your |
|
13d2b8934445
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|
1888 �SYNTAX_ERROR� macro. You might use this option if your |
|
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1889 parser is dealing directly with keyboard input. |
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1890 |
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1891 You may wish to use YACC type error handling. To do |
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1892 this, simply incorporate a token called "error" in your |
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1893 grammar, or specify some other token as an �error |
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1894 token�. On syntax error, your parser will back up to |
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1895 the most recent state where "error" was acceptable |
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1896 input, treat the bad input as an instance of error, and |
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1897 then skip all input until it finds an acceptable input |
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1898 token. At that point it will proceed as though nothing |
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1899 had happened. |
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1900 |
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1901 AnaGram also provides an �automatic resynchronization� |
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1902 option, which uses a complex heuristic to compare input |
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1903 tokens against all stacked states in order to find the |
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1904 best state from which to continue. |
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1905 ## |
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1906 |
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1907 Error Token Resynchronization |
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1908 |
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1909 One of your options for �error recovery� after a �syntax |
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1910 error� is a technique similar to that provided in YACC. |
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1911 You include a terminal token called "error" in your |
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1912 grammar. (Or, use the �error token� configuration |
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1913 parameter to specify some other token to serve this |
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1914 purpose.) When the parser encounters an error in the |
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1915 input, after invoking the �SYNTAX_ERROR� macro, it backs |
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1916 up the �parser state stack� to the most recent state in |
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1917 which "error" was an acceptable input. It then shifts to |
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1918 the new state as though it had seen an actual "error" |
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1919 token. At this point, it skips over any character in the |
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1920 input which is not an acceptable input character for |
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1921 this state. Once it does find an acceptable input |
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1922 character, it continues processing as though nothing had |
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1923 happened. |
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1924 ## |
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1925 |
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1926 error_frame_ssx |
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1927 |
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1928 error_frame_ssx is a field in a �parser control block� |
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1929 to which your �error handling� routines may refer. When |
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1930 your �SYNTAX_ERROR� macro is called, if you have set |
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1931 both the �diagnose errors� and �error frame� |
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1932 configuration switches, error_frame_ssx will contain the |
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1933 value of the �parser stack index� at the beginning of |
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1934 the �error_frame_token�. For example, if in a syntax |
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1935 file, you fail to close a comment, AnaGram will |
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1936 encounter an illegal end of file in the comment. In this |
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1937 situation, error_frame_token is the token for a comment, |
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1938 and error_frame_ssx gives the parser stack depth at the |
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1939 beginning of the comment. |
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1940 ## |
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1941 |
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1942 error_frame_token |
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1943 |
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1944 error_frame_token is a field in a �parser control block� |
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1945 to which your �error handling� routines may refer. If |
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1946 you have set both the �diagnose errors� and �error |
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1947 frame� �configuration switch�es, when your |
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1948 �SYNTAX_ERROR� macro is called, it will contain the |
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1949 �token number� of the error_frame_token. |
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1950 ## |
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1951 |
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1952 error, Error Token |
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1953 |
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1954 "Error token" is a �configuration parameter� that takes |
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1955 a token name for a value. It has no default value. If |
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1956 you do not specify it, and your grammar has a terminal |
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1957 token called "error", it will be used as the error |
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1958 token. If you have an error token defined your parser |
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1959 will presume that you wish to use the �error token |
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1960 resynchronization� method of �error recovery�. |
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1961 ## |
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1962 |
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1963 Escape Backslashes |
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1964 |
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1965 "�Escape backslashes�" is a �configuration switch� that |
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1966 defaults to off. When turned on, the �line numbers� switch |
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1967 will write pathnames with doubled backslashes. The switch |
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1968 is no longer necessary, since AnaGram now uses forward slashes |
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1969 in the pathnames in #line directives rather than backslashes.switch. |
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1970 ## |
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1971 |
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1972 Event Driven |
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1973 |
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1974 It is often convenient to configure your parser to be |
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1975 "event driven". In this situation, instead of calling |
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1976 your parser once to process the entire input, you call |
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1977 an �initializer� to initialize the parser, and then you |
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1978 call the parser once for each input token. Each time you |
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1979 call it, the parser processes the single input token |
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1980 until it can do no more. |
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1981 |
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1982 You can interrogate the �exit_flag� field of the |
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1983 �parser control block� to determine whether the parse is |
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1984 complete or whether the parser encountered an error. |
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1985 |
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1986 Event driven parsers are especially convenient for |
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1987 dealing with terminal input or communications protocols. |
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1988 ## |
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1989 |
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1990 Event Driven Parser Cannot Use Pointer Input |
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1991 |
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1992 This �warning� message appears if you specify pointer |
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1993 input for your �parser� and also specify that it should |
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1994 be event driven. If you are going to use �pointer |
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1995 input�, you should not specify your �parser� as event |
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1996 driven. Conversely, if you really want an �event |
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1997 driven� parser, you cannot specify pointer input. |
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1998 ## |
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1999 |
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2000 Excessive Recursion |
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2001 |
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2002 This �warning� message appears if an internal stack in |
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2003 AnaGram overflows because of the complexity of an |
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2004 expression in your �grammar�. Simplify your grammar by |
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2005 using �definition� statements to name subexpressions. |
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2006 ## |
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2007 |
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2008 exit_flag |
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2009 |
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2010 exit_flag is a field in the �parser control block�. |
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2011 When your parser returns, PCB.exit_flag contains an exit |
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2012 code describing the outcome of the parse. Mnemonic |
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2013 values for the exit codes are defined in the parser |
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2014 header file AnaGram generates. These mnemonics, their |
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2015 values and their meanings are: |
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2016 AG_RUNNING_CODE = 0: Parse is not yet complete |
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2017 AG_SUCCESS_CODE = 1: Parse terminated successfully |
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2018 AG_SYNTAX_ERROR_CODE = 2: Syntax error encountered |
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2019 AG_REDUCTION_ERROR_CODE = 3: Bad reduction token encountered |
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2020 AG_STACK_ERROR_CODE = 4: Parser stack overflowed |
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2021 AG_SEMANTIC_ERROR_CODE = 5: Semantic error, user defined |
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2022 |
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|
2023 An AnaGram parser checks exit_flag on return |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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2024 from every �reduction procedure�. AnaGram will exit with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2025 the flag unchanged if it is non-zero. To halt a parse |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2026 from a reduction procedure, then, you need only set the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2027 exit_flag to AG_SEMANTIC_ERROR_CODE, or any other unused value |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2028 greater than zero that suits your needs. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2029 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2030 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2031 Expansion, Expansion Rule |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2032 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2033 In analyzing a �grammar�, we are often interested in the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2034 full range of input that can be expected at a certain |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2035 point. The expansion of a �token� or state shows us |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2036 all the expected input. An expansion yields a set of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2037 �marked rule�s. The �marked token� in each rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2038 shows us what input to expect. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2039 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2040 The set of expansion rules of a (�nonterminal�) token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2041 shows all the expected input that can occur whenever the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2042 token appears in the grammar. The set consists of all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2043 the �grammar rule�s produced by the token, plus all the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2044 rules produced by the first token of any rule in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2045 set. A �marked token� for an expansion rule of a token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2046 is the first element in the rule. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2047 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2048 The expansion of a state consists of its �characteristic |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2049 rule�s plus the expansion rules of the marked token in each |
|
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|
2050 characteristic rule. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2051 ## |
|
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2052 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2053 Expansion Chain |
|
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Import AnaGram (near-)release tree into Mercurial.
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parents:
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|
2054 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2055 You may select an Expansion Chain window from the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2056 �Auxiliary Windows� popup menu of most windows that contain |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2057 �expansion rule�s. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2058 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2059 The Expansion Chain window is extremely useful for |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2060 indicating why a particular �grammar rule� is an |
|
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David A. Holland
parents:
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|
2061 �expansion rule� in a particular state. To see a chain |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2062 of productions that produces a desired expansion rule, |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2063 select the expansion rule with the cursor bar, press |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2064 the right mouse button for the Auxiliary Windows menu, and select |
|
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Import AnaGram (near-)release tree into Mercurial.
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parents:
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|
2065 Expansion Chain. |
|
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|
2066 |
|
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David A. Holland
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|
2067 The Expansion Chain window will then present a sequence |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2068 of expansion rules, using the same format as the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2069 Expansion Rules window, but subject to the constraint |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2070 that each rule is produced by the �marked token� in the previous line. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2071 |
|
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|
2072 The first rule in the window is a �characteristic rule� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2073 for the given state. The last rule in the window is |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2074 the rule selected by the cursor bar in the window from |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2075 which you chose the Expansion Chain. It should be noted |
|
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David A. Holland
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|
2076 that this expansion is not unique. There may be other |
|
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David A. Holland
parents:
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|
2077 derivations. |
|
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David A. Holland
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|
2078 ## |
|
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|
2079 |
|
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|
2080 Expansion Rules |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2081 |
|
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David A. Holland
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|
2082 You may select an Expansion Rules window from the |
|
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|
2083 �Auxiliary Windows� popup menu of most windows which display |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2084 �marked rules�. The Expansion Rules window shows the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2085 complete set of �expansion rule�s for the �marked |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2086 token� in the highlighted rule. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2087 |
|
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|
2088 In other windows, including all trace windows, the |
|
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David A. Holland
parents:
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|
2089 Expansion Rules window shows the expansion of the token |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2090 on the highlighted line. |
|
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David A. Holland
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|
2091 ## |
|
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|
2092 |
|
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|
2093 F1 |
|
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|
2094 |
|
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|
2095 Use the F1 key to bring up a context sensitive help window. Because of |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2096 various peculiarities of the Windows API, there are a few contexts |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2097 where the F1 key does not work; however, generally the �help cursor� |
|
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2098 works where F1 does not and vice versa. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2099 |
|
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2100 �Help� windows have hypertext links to related help windows. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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2101 In a help window, the right mouse button pops up a menu of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2102 all the links for the window. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2103 ## |
|
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|
2104 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2105 extend pcb |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2106 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2107 The "extend pcb" statement is an �attribute statement� that allows you to |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2108 add declarations of your own to the �parser control block�. With this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2109 feature, data needed by �reduction procedure�s can be stored in the pcb |
|
13d2b8934445
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|
2110 rather than in global or static storage. This capability greatly |
|
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David A. Holland
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|
2111 facilitates the construction of �thread safe parsers�. |
|
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|
2112 |
|
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|
2113 The extend pcb statement may be used in any configuration section. |
|
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|
2114 The format is as follows: |
|
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|
2115 extend pcb { <C or C++ declaration>... } |
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2116 |
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2117 It may, of course, extend over multiple lines and may contain any |
|
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|
2118 C or C++ declarations. AnaGram will append it to the end of the parser |
|
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Import AnaGram (near-)release tree into Mercurial.
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2119 control block declaration in the generated parser �header file�. There may |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2120 be any number of extend pcb statements. The extensions are appended to |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2121 the pcb in the order in which they occur in the syntax file. |
|
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|
2122 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2123 The extend pcb statement is compatible with both C and C++ parsers. Note |
|
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|
2124 that even if you are deriving your own class from the parser control |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2125 block, you might want to use the extend pcb to provide virtual function |
|
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|
2126 definitions or other declarations appropriate to a base class. |
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|
2127 ## |
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|
2128 |
|
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parents:
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|
2129 Far Tables |
|
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parents:
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|
2130 |
|
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|
2131 "Far tables" is a �configuration switch� which defaults |
|
13d2b8934445
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|
2132 to off. If it is set, when AnaGram builds a �parser� it |
|
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|
2133 will declare the larger tables it builds as FAR. This |
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|
2134 can be a convenience when using some memory models with |
|
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|
2135 8086 architecture. |
|
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David A. Holland
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|
2136 ## |
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parents:
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|
2137 |
|
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|
2138 Fatal Syntax Errors |
|
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parents:
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|
2139 |
|
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|
2140 This �warning� message occurs when AnaGram cannot |
|
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|
2141 complete the �Analyze Grammar� command on your �syntax |
|
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parents:
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|
2142 file� because of errors in your syntax file. |
|
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|
2143 ## |
|
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|
2144 |
|
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|
2145 File Trace |
|
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David A. Holland
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|
2146 |
|
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|
2147 You can use the File Trace facility to verify your grammar, |
|
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|
2148 even before you have implemented �reduction procedures� or |
|
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parents:
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|
2149 any other code. Thus you can defer writing procedural code |
|
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diff
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|
2150 until you have the grammar working to your specifications. |
|
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|
2151 |
|
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parents:
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|
2152 To run File Trace, select |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2153 File Trace from the �Action Menu� or click on the File Trace button. |
|
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Import AnaGram (near-)release tree into Mercurial.
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parents:
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|
2154 |
|
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David A. Holland
parents:
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|
2155 Select a test file. When the �File Trace Window� appears, |
|
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David A. Holland
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|
2156 double click at any point in the �test file pane�, or |
|
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David A. Holland
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|
2157 click the �Parse File� button to parse the entire file. |
|
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David A. Holland
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|
2158 AnaGram will parse up to the point you have selected |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2159 according to the rules in your �grammar�. If the test file does not |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2160 conform to the rules of the grammar, the parse will halt with a |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2161 �syntax error�. You can then inspect the �Parser Stack pane� and the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2162 �Rule Stack pane� to get an idea of the nature of the problem. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2163 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2164 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2165 AnaGram uses different colors to |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2166 distinguish the portion of the test file that has |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2167 been parsed from the portion that has not been parsed, |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2168 so the location of the error should be readily apparent. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2169 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2170 Since the syntax error often occurs somewhat downstream |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2171 from the actual error, you may need to back the parse up |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2172 and approach the error slowly. In the Test File pane, |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2173 double click at any point prior to the error to back |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2174 the parse up to that point. You can then click on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2175 �Single Step� button to perform a single parser action. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2176 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2177 You may also use the cursor keys to control the parse. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2178 As long as no error is encountered, the parse is locked |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2179 to the blinking cursor. If you cursor past the syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2180 error, however, the parse can no longer track the cursor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2181 so the cursor location will differ from the parse location . The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2182 cursor and parse locations will also differ after you single click |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2183 at any point other than the current parse location. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2184 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2185 When the cursor and the parse location are thus out of synch, the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2186 Single Step button is replaced with a �Synch Parse� button. You |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2187 can click on Synch Parse to get the parse back in synch with the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2188 cursor. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2189 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2190 The File Trace option will be greyed out on the �Action Menu� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2191 if your grammar has �empty recursion�, since |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2192 such a grammar may cause infinite loops in the parser. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2193 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2194 Because a File Trace is based on character codes, it will also be greyed out |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2195 on the �Action Menu� if your parser uses �token input� rather than |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2196 character input. |
|
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David A. Holland
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|
2197 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2198 All parser actions performed by a File Trace update the �trace |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2199 coverage� counts, enabling you to verify the extent to which |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2200 your test files exercise your parser. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2201 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2202 Normally, AnaGram reads test files in "text" mode, |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2203 discarding carriage return characters. If your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2204 needs to recognize carriage return characters |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2205 explicitly, you should turn the "�test file binary�" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2206 switch on. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2207 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2208 |
|
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David A. Holland
parents:
diff
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|
2209 File Trace Window |
|
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David A. Holland
parents:
diff
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|
2210 |
|
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David A. Holland
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|
2211 The �File Trace� window normally consists of three panes: |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2212 The �Parser Stack pane� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2213 The �Test File pane� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2214 The �Rule Stack pane� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2215 |
|
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David A. Holland
parents:
diff
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|
2216 If your grammar uses �semantically determined productions�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2217 the �Reduction Choices pane� will appear when necessary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2218 to allow you to select a �reduction token�. The choice that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2219 you make will be remembered and reused if you should back up |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2220 the parse and parse past this point again. The remombered choice |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2221 is not made automatically when you use �Single Step�. Thus, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2222 if you wish to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2223 change your choice, position the cursor at the location where |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2224 the choice must be made and Single Step past the choice. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2225 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2226 If you �reload� the test file, the choices you have made will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2227 be discarded. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2228 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2229 The active pane has |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2230 a distinctively colored title panel and cursor bar. You can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2231 use the tab key to tab among the panes. The function of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2232 other keyboard keys depends on which pane is active. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2233 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2234 Along the bottom of the File Trace Window is a toolbar with |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2235 two status boxes: |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2236 �Parse Location� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2237 �Parse Status� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2238 and five buttons: |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2239 �Single Step� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2240 �Parse File� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2241 �Reset� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2242 �Reload� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2243 �Help� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2244 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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diff
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|
2245 If the blinking cursor loses synch with the current |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2246 parse location, the Single Step button is replaced with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2247 the �Synch Parse� button. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2248 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2249 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2250 Grammar Trace Window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2251 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2252 The �Grammar Trace� window normally consists of three panes: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2253 The �Parser Stack pane� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2254 The �Allowable Input pane� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2255 The �Rule Stack pane� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2256 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2257 If your grammar uses �semantically determined productions�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2258 the �Reduction Choices pane� will appear when necessary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2259 to allow you to select a �reduction token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2260 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2261 The active pane has |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2262 a distinctively colored column header and cursor bar. You |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2263 can use the tab key to tab among the panes. The function of other |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2264 keyboard keys depends on which pane is active. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2265 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2266 Along the bottom of the Grammar Trace Window is a toolbar with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2267 a �Parse Status� box, a �text entry� field |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2268 and four buttons: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2269 �Proceed� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2270 �Single Step� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2271 �Reset� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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diff
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|
2272 �Help� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2273 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2274 In the �Parser Stack pane� you can see a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2275 representation of the �parser state stack� and �parser state� as they |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2276 might appear in the course of execution of your �parser�. You can |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2277 examine the �allowable input� tokens and see the changes to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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diff
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|
2278 state and the state stack caused by any input token you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2279 choose. The �Rule Stack pane� shows the relationship between the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2280 contents of the parser stack and your �grammar�. If your grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2281 uses �semantically determined productions�, you can select the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2282 appropriate �reduction token� from the �Reduction Choices pane�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2283 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2284 You can enter text characters directly in the �text entry� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2285 field. This means you can run a Grammar Trace like a �File Trace� |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2286 where the test file is replaced by the characters you type in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2287 text entry field. This is a very convenient way to check out your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2288 grammar. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2289 ## |
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2290 |
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|
2291 Test File, Test File Pane |
|
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|
2292 |
|
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|
2293 In the �File Trace�, the file under test is displayed in the |
|
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|
2294 upper right pane. To parse to a specific point, double |
|
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2295 click at that point. |
|
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|
2296 |
|
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|
2297 As long as the parse location and the cursor are synchronized, |
|
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|
2298 when you use the cursor keys to |
|
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David A. Holland
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|
2299 move the cursor, the parse will track the cursor. |
|
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|
2300 |
|
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|
2301 If the parse encounters a �syntax error�, it will not be able |
|
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2302 to go beyond the location of the error. In this situation, |
|
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David A. Holland
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|
2303 moving the cursor right or down will cause the cursor position to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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2304 differ from the parse location. The parse and cursor positions can also |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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2305 differ if you single click anywhere in the Test File pane. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2306 |
|
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|
2307 If the |
|
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|
2308 parse location and the cursor are thus not synchronized, the |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2309 �Single Step� button will be replaced with a �Synch Parse� |
|
13d2b8934445
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|
2310 button. Click on the Synch Parse button to get the cursor |
|
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David A. Holland
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|
2311 and the parse back in synch. Of course, the parse will still |
|
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|
2312 not be able to proceed past a syntax error. |
|
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|
2313 |
|
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David A. Holland
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|
2314 In the default color scheme, parsed text is shown on a lighter |
|
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David A. Holland
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|
2315 background than is unparsed text. |
|
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2316 |
|
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2317 If your grammar uses �semantically determined production�s, |
|
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|
2318 the parse will halt when one is encountered and the �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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2319 choices pane� will be displayed so you may select the appropriate |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2320 �reduction token�. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2321 |
|
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David A. Holland
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|
2322 At any time you can click on the �Reset button� to reset the parse to |
|
13d2b8934445
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2323 the beginning of the test file. If you modify the test file, you |
|
13d2b8934445
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David A. Holland
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|
2324 can click on the �Reload button� to load the modified file and |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2325 reset the parse. |
|
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|
2326 |
|
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|
2327 Normally, AnaGram reads test files in "text" mode, discarding carriage |
|
13d2b8934445
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|
2328 return characters. If your parser needs to recognize carriage return |
|
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David A. Holland
parents:
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|
2329 characters explicitly, you should turn the �test file binary� |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2330 �configuration switch� on. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2331 |
|
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|
2332 Sample test files are provided with the FFCALC and FC �examples�. |
|
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|
2333 ## |
|
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|
2334 |
|
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|
2335 Parse Location |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2336 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2337 The current location of the �File Trace� parser in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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diff
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|
2338 �test file pane�. The format is <line number>:<column number>. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2339 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2340 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2341 Parse Status |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2342 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2343 The current state of the �File Trace� or �Grammar Trace� parser. |
|
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|
2344 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2345 Ready: The parser is ready for input. |
|
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|
2346 Running: The parser is processing input. |
|
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Import AnaGram (near-)release tree into Mercurial.
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2347 Parse Complete: The parser has reached the end of the input. Click |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2348 on �reset� or �reload� to restart the parse. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2349 Syntax error: A syntax error has been encountered. The parser cannot |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2350 go any further. |
|
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Import AnaGram (near-)release tree into Mercurial.
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2351 Unexpected end of file: The parser has reached the end of the actual |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2352 input but the grammar still expects more. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2353 Select reduction token: The parser encountered a �semantically determined |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2354 production�. Select a �reduction token� from the �Reduction Choices pane�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2355 Selection error: The reduction token selected from the Reduction Choices |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2356 pane was not allowable input in the present state. Select another |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2357 reduction token. |
|
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|
2358 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2359 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2360 Parse File |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2361 |
|
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Import AnaGram (near-)release tree into Mercurial.
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2362 Use the Parse File button in the �File Trace� to parse all the way |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2363 to the end of file. The parse will not stop until it encounters a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2364 �syntax error�, a �semantically determined production�, or the end of file. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2365 ## |
|
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|
2366 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2367 Reset |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2368 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2369 Use the Reset button in the �File Trace� or �Grammar Trace� to reset |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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parents:
diff
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|
2370 the parse to its initial state. This is most convenient when using |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2371 a �Conflict Trace�, �Error Trace�, or other �Auxiliary Trace� |
|
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Import AnaGram (near-)release tree into Mercurial.
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diff
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|
2372 since these traces seldom begin at state 0. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2373 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2374 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2375 Reload |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2376 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2377 The Reload button in the �File Trace Window� rereads the test file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2378 This is convenient if you modify the test file while you are testing |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2379 the �grammar�. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2380 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2381 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2382 Lookahead Token |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2383 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2384 In an �LALR-1 parser� the "lookahead token" is the next token to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2385 processed. For each �parser state� there is a list of tokens that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2386 may be seen in this state. For each token there is a corresponding |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2387 �parser action�. The parser scans the list looking for the lookahead |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2388 token and then performs the corresponding parser action. If the |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2389 lookahead token cannot be found and there is no �default reduction�, |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2390 the parser signals a �syntax error�. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2391 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2392 In File Trace, and in some circumstances in Grammar Trace, the |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2393 lookahead token can be seen on the last line of the |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2394 �Parser Stack pane�. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2395 ## |
|
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|
2396 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2397 GET_CONTEXT |
|
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|
2398 |
|
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|
2399 If you have defined a "�context type�" �configuration |
|
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|
2400 parameter�, and wish to maximize the performance of your |
|
13d2b8934445
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|
2401 parser, you should write a GET_CONTEXT macro which |
|
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David A. Holland
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|
2402 stores the context of the input token directly in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2403 �CONTEXT�, the current stack location. Otherwise, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2404 can write your �GET_INPUT� macro so that it stores |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2405 context into �PCB�.�input_context�. The default |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2406 definition for GET_CONTEXT will then copy |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2407 PCB.input_context to the �context stack� at the |
|
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|
2408 appropriate time. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2409 ## |
|
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|
2410 |
|
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|
2411 GET_INPUT |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2412 |
|
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|
2413 GET_INPUT is a macro which you should define to control |
|
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|
2414 �parser input� if your |
|
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parents:
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|
2415 parser is not �event driven� and you are not using |
|
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|
2416 �pointer input�. If you don't define it, AnaGram will |
|
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|
2417 define it by default to read a single character from |
|
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|
2418 stdin: |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2419 |
|
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|
2420 #define GET_INPUT (PCB.input_code = getchar()) |
|
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|
2421 |
|
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|
2422 �PCB�.�input_code� is an integer field in the �parser control block� |
|
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2423 which is used to hold the current character code. You |
|
13d2b8934445
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David A. Holland
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|
2424 may also want GET_INPUT to set the values of �input_context� or |
|
13d2b8934445
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David A. Holland
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|
2425 �input_value�. It may call an input function, or it may execute |
|
13d2b8934445
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David A. Holland
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|
2426 in-line code when it is invoked. |
|
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|
2427 ## |
|
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|
2428 |
|
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|
2429 iso latin 1 |
|
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|
2430 |
|
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|
2431 The "iso latin 1" �configuration switch� controls case |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2432 conversion on input characters when the �case sensitive� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2433 switch is set to off. When "iso latin 1" is set, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2434 default �CONVERT_CASE� macro is defined to convert |
|
13d2b8934445
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David A. Holland
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|
2435 correctly all characters in the latin 1 character set. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2436 When the switch is off, only characters in the ASCII |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2437 range (0-127) are converted. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2438 ## |
|
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|
2439 |
|
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|
2440 Dragon Book |
|
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|
2441 |
|
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2442 The "dragon book" is the classic reference on formal parsing: |
|
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|
2443 Compilers: Principles, Techniques, and Tools |
|
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|
2444 Aho, Sethi, and Ullman |
|
13d2b8934445
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|
2445 Addison-Wesley, 1986. |
|
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|
2446 |
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|
2447 It is called the "dragon book" because of its |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2448 colorful cover illustration showing a knight in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2449 armour ("data flow analysis") armed with sword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2450 ("�LALR parser generator�") and shield ("syntax |
|
13d2b8934445
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David A. Holland
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diff
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|
2451 directed translation") at his PC attacking a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2452 bright red dragon ("complexity of compiler design"). |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2453 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2454 |
|
13d2b8934445
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|
2455 LALR-1 Parser |
|
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David A. Holland
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diff
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|
2456 |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2457 An LALR-1 parser is a �parser� created from a |
|
13d2b8934445
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|
2458 �grammar� by an �LALR parser generator�. |
|
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David A. Holland
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|
2459 ## |
|
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|
2460 |
|
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|
2461 LALR Parser Generator |
|
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|
2462 |
|
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|
2463 LALR(k) (LookAhead Left-to-right Rightmost derivation) |
|
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|
2464 parser generators are |
|
13d2b8934445
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David A. Holland
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|
2465 programs that create parsers algorithmically from |
|
13d2b8934445
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David A. Holland
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|
2466 formal grammars. The (k) refers to the number of |
|
13d2b8934445
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diff
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|
2467 lookahead symbols used to make parsing decisions. |
|
13d2b8934445
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David A. Holland
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|
2468 Normally, k = 1. |
|
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|
2469 |
|
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|
2470 LALR parsers are a subset of the class of |
|
13d2b8934445
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David A. Holland
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|
2471 so-called LR parsers. LALR parsers are generally more compact |
|
13d2b8934445
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|
2472 and less costly to create. These advantages are |
|
13d2b8934445
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|
2473 obtained at a slight sacrifice in generality. Although |
|
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|
2474 is possible to contrive an LR grammar which has |
|
13d2b8934445
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David A. Holland
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|
2475 �conflict�s when analyzed with the LALR algorithm, |
|
13d2b8934445
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|
2476 such situations rarely occur in practice, and can |
|
13d2b8934445
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David A. Holland
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|
2477 be easily resolved by rewriting a few rules. |
|
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David A. Holland
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|
2478 |
|
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|
2479 In the �dragon book�, section 4.7, the authors list the following |
|
13d2b8934445
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|
2480 attractive properties of LR parsing: |
|
13d2b8934445
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David A. Holland
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|
2481 LR parsers can be constructed to recognize virtually |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2482 all programming-language constructs for which context-free |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2483 grammars can be written. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2484 The LR parsing method is the most general nonbacktracking |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2485 shift-reduce parsing method known, yet it can be implemented as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2486 efficiently as other shift-reduce methods. |
|
13d2b8934445
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David A. Holland
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|
2487 The class of grammars that can be parsed using LR methods is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2488 a superset of the class of grammars that can be parsed with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2489 predictive parsers. |
|
13d2b8934445
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David A. Holland
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|
2490 An LR parser can detect a syntactic error as soon as it is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2491 possible to do so on a left-to-right scan of the input. |
|
13d2b8934445
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|
2492 ## |
|
13d2b8934445
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|
2493 |
|
13d2b8934445
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|
2494 Getting Started |
|
13d2b8934445
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|
2495 |
|
13d2b8934445
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David A. Holland
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|
2496 AnaGram is an �LALR parser generator�. Its input is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2497 a �syntax file�, which you prepare with an ordinary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2498 programming editor. Its output is a �parser file�. which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2499 you can compile with a C or C++ compiler on any platform |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2500 and link into your program. To compile on Unix platforms, set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2501 the �no cr� �configuration switch�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2502 |
|
13d2b8934445
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parents:
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|
2503 AnaGram has extensive context-sensitive hypertext |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2504 �help�. In any AnaGram window, press �F1� or select an item with the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2505 �Help Cursor�. Further documentation in HTML format, including |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2506 documentation of examples, is found in the html subdirectory. AnaGram |
|
13d2b8934445
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David A. Holland
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diff
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|
2507 also has a comprehensive hard-copy manual, the AnaGram User's Guide. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2508 |
|
13d2b8934445
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|
2509 If you are new to AnaGram, you might begin by reviewing the Help |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2510 Topics �How AnaGram Works� and �Program Development�, and looking at |
|
13d2b8934445
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David A. Holland
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diff
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|
2511 An Annotated Example and Summary of AnaGram Notation in the HTML |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
2512 documentation. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2513 |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
2514 If you are not already familiar with formal parsing techniques, you |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
2515 may want to read Introduction to Syntax Directed Parsing in the HTML |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2516 documentation. Note also the Fahrenheit to Celsius conversion |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2517 examples in the examples/fc directory, which comprise a graded |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
2518 sequence of syntax files illustrating most of the basic |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2519 principles of �syntax directed parsing� in easy steps. Documentation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2520 is in html/fc.html. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
2521 |
|
13d2b8934445
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David A. Holland
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|
2522 AnaGram has many features, many of which are not |
|
13d2b8934445
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|
2523 commonly found in parser generators: |
|
13d2b8934445
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diff
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|
2524 the �configuration section� |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2525 �thread safe parsers� |
|
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|
2526 C++ support |
|
13d2b8934445
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parents:
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|
2527 the �disregard� and �lexeme� statements |
|
13d2b8934445
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|
2528 �event driven� parsers |
|
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|
2529 �character sets� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2530 �virtual productions� |
|
13d2b8934445
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|
2531 �File Trace�, �Grammar Trace� |
|
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|
2532 �automatic resynchronization� |
|
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|
2533 �error token resynchronization� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2534 |
|
13d2b8934445
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|
2535 To familiarize yourself with the many options available for configuring |
|
13d2b8934445
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diff
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|
2536 your parsers, select �Configuration Parameters� from the �Browse Menu�. |
|
13d2b8934445
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|
2537 Use �F1� or the �Help Cursor� to pop up explanations of the various |
|
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|
2538 parameters. |
|
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|
2539 |
|
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|
2540 |
|
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|
2541 If you don't find the information you need, please visit the |
|
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|
2542 AnaGram web page at http://www.parsifalsoft.com for further |
|
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|
2543 information and support. |
|
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|
2544 |
|
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|
2545 ## |
|
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|
2546 |
|
13d2b8934445
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|
2547 How AnaGram Works |
|
13d2b8934445
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|
2548 |
|
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|
2549 AnaGram contains an �LALR Parser Generator� which creates a |
|
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|
2550 table driven �LALR-1 parser� from a �grammar� written in a variant |
|
13d2b8934445
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|
2551 of Backus-Naur Form. AnaGram works in two steps. In the |
|
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|
2552 first step, or analysis phase, it reads a �syntax file� and |
|
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|
2553 compiles a number of tables describing the grammar. In the |
|
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|
2554 second step, or build phase, it writes two output files: |
|
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|
2555 a �parser file� written in C or C++ and a �header file�. |
|
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2556 |
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2557 Syntax files normally have the extension .syn. The rules for |
|
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|
2558 writing syntax files are given in the AnaGram User's Guide |
|
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David A. Holland
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|
2559 and in the Summary of AnaGram Notation in the HTML documentation. |
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2560 |
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|
2561 The header file contains definitions and declarations, including |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2562 the definition of a �parser control block�. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2563 |
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Import AnaGram (near-)release tree into Mercurial.
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|
2564 The parser file consists of: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2565 The �C prologue�, if any. |
|
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|
2566 Definitions and declarations provided by AnaGram. |
|
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|
2567 �Reduction procedure�s. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2568 a customized �parsing engine�. |
|
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|
2569 a �parse function� to be called when input is to be parsed. |
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2570 |
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2571 The name of the parser file is controlled by the �parser |
|
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|
2572 file name� �configuration parameter�. The name of the |
|
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|
2573 parse function itself is controlled by �parser name�. In the |
|
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|
2574 default case, the parser file will have the same name as |
|
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|
2575 the syntax file, with the extension .c. The name of the |
|
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|
2576 parse function is given by the �parser name� parameter. It defaults |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
2577 to the name of the syntax file. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2578 ## |
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2579 |
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|
2580 Examples |
|
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2581 |
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2582 The EXAMPLES directory of the AnaGram distribution disk |
|
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2583 contains a number of examples to help you get started. |
|
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|
2584 Documentation for the examples, in HTML format, is located |
|
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|
2585 in the html directory (start at index.html or examples.html). |
|
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2586 |
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2587 The traditional Hello, World, in examples/hw, is a good |
|
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|
2588 example for getting familiar with the mechanical |
|
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|
2589 procedures of building both C and C++ parsers from |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2590 �syntax file�s. |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2591 |
|
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|
2592 The Fahrenheit/Celsius conversion examples in the |
|
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|
2593 examples/fc directory on your AnaGram diskette comprise |
|
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|
2594 a graded sequence of syntax files which illustrate |
|
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|
2595 most of the basic principles of �syntax directed |
|
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|
2596 parsing� in easy steps. In addition, these examples |
|
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|
2597 demonstrate many features of AnaGram which are not |
|
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|
2598 found in other parser generators: |
|
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|
2599 the �configuration section� |
|
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|
2600 �character sets� |
|
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|
2601 �virtual productions� |
|
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|
2602 �error token resynchronization� |
|
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|
2603 �File Trace� |
|
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2604 the �disregard� and �lexeme� statements |
|
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|
2605 �event driven� parsers |
|
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2606 |
|
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|
2607 The Four Function Calculator (examples/ffcalc) is used |
|
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|
2608 traditionally to demonstrate parser generators. If you |
|
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|
2609 are already familiar with �syntax directed parsing� this |
|
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|
2610 example will give you a good overview of the basics of |
|
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|
2611 AnaGram. An annotated version of this example may be |
|
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|
2612 found in AnaGram's HTML documentation. |
|
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|
2613 The FFCALC example illustrates the use of �precedence |
|
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|
2614 rules� to resolve �conflicts�. |
|
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|
2615 |
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2616 Other examples are available to demonstrate additional |
|
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|
2617 features of AnaGram. |
|
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2618 |
|
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|
2619 RCALC (examples/rcalc) is a simple four function |
|
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|
2620 calculator which accepts roman numeral input. It |
|
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|
2621 illustrates the following AnaGram features: |
|
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|
2622 �pointer input� |
|
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|
2623 �SYNTAX_ERROR� macro |
|
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|
2624 �context stack� |
|
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|
2625 |
|
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|
2626 DSL (examples/dsl) is a complete DOS script language, |
|
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|
2627 which provides capabilities well in excess of DOS batch |
|
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|
2628 files. DSL is a complete working program, used in the |
|
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|
2629 past to create AnaGram's install program. Some of the |
|
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|
2630 specific features of AnaGram which it illustrates are: |
|
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|
2631 �distinguish lexemes� |
|
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|
2632 �distinguish keywords� |
|
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|
2633 �far tables� |
|
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|
2634 |
|
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2635 MPP is a fully functional macro preprocessor for C or |
|
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2636 C++. Included with MPP are two C grammars, either of |
|
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|
2637 which may be incorporated into MPP. MPP uses several |
|
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|
2638 parsers that work together: |
|
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|
2639 TS.SYN is the primary token scanner parser that |
|
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|
2640 identifies tokens, and handles preprocessor |
|
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|
2641 commands. |
|
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|
2642 MAS.SYN is used to do macro argument substitution. |
|
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|
2643 CT.SYN is used to identify tokens that result from |
|
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|
2644 string concatenation during macro argument |
|
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|
2645 substitution. |
|
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|
2646 EX.SYN is used to evaluate constant expressions in |
|
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|
2647 #if preprocessor statements. |
|
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|
2648 |
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2649 Among the more powerful features of AnaGram that MPP |
|
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|
2650 illustrates are: |
|
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|
2651 �semantically determined productions� |
|
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|
2652 �event driven� parsers |
|
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|
2653 ## |
|
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2654 |
|
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2655 Goal, Goal Token, Start Token |
|
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2656 |
|
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2657 The �grammar token� is the token which represents the |
|
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|
2658 "top level" in your grammar. Some people refer to it as |
|
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|
2659 the "goal" or "goal token" and others as the "start |
|
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|
2660 token". Whichever it is called, it is the single token |
|
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|
2661 which describes the complete input to your parser. |
|
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2662 |
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|
2663 The most common way to specify a grammar token is as |
|
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2664 follows: |
|
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|
2665 grammar -> statements?..., eof |
|
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2666 This production tells AnaGram that the input to your |
|
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2667 parser consists of a (possibly empty) sequence of |
|
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|
2668 statements followed by an end of file token. |
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2669 |
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2670 There are a number of ways of specifying which token in |
|
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2671 your �syntax file� represents the top level of your |
|
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2672 grammar. You may simply name it "grammar", or you may |
|
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2673 tag it with a '$' character when you define it, or you |
|
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2674 may set the �grammar token� �configuration parameter�. |
|
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|
2675 |
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2676 If you should inadvertently tag several tokens with the |
|
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2677 '$' character and/or set the grammar token parameter, |
|
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|
2678 it is the last such specification in the file which |
|
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|
2679 wins. Some people develop their grammars bottom up, |
|
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2680 gradually adding new levels of complexity. In the |
|
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2681 course of development, they may specify a number of |
|
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|
2682 tokens as grammar tokens and forget to remove the old |
|
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|
2683 specifications. |
|
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2684 |
|
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2685 Notice that if you define the token "grammar" anywhere |
|
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2686 in your syntax and specify the grammar token otherwise, |
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2687 "grammar" will not be the grammar token. This is to |
|
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|
2688 keep "grammar" from being a reserved word. If you need |
|
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|
2689 to use it in your syntax for something other than the |
|
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|
2690 whole grammar, you are free to do so. |
|
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|
2691 ## |
|
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2692 |
|
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|
2693 Grammar |
|
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|
2694 |
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|
2695 Traditionally, a "grammar" is a set of �production�s |
|
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|
2696 which taken together specify precisely a set of |
|
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David A. Holland
parents:
diff
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|
2697 acceptable input streams, in terms of an abstract set |
|
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David A. Holland
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|
2698 of �terminal tokens�. The set of acceptable input |
|
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|
2699 streams is often called the "language" defined by the |
|
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|
2700 grammar. |
|
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|
2701 |
|
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|
2702 In AnaGram, the term "grammar" also includes |
|
13d2b8934445
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|
2703 �configuration sections� as well as the �definitions� |
|
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|
2704 of �character sets� and �virtual productions� which |
|
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|
2705 augment the collection of productions. The term is |
|
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|
2706 often used in contrast to the term "�syntax file�" |
|
13d2b8934445
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parents:
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|
2707 which is used to signify the complete AnaGram source |
|
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|
2708 file including reduction procedures and embedded C or |
|
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David A. Holland
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|
2709 the term "�parser�" which refers to AnaGram's output |
|
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|
2710 file. |
|
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|
2711 |
|
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|
2712 A grammar is often called a "syntax", and the rules of |
|
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diff
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|
2713 the grammar are often called syntactic rules. |
|
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|
2714 ## |
|
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2715 |
|
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|
2716 Grammar Analysis |
|
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|
2717 |
|
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|
2718 The major function of AnaGram is the analysis of |
|
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|
2719 context-free grammars written in a particular variant |
|
13d2b8934445
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|
2720 of Backus-Naur Form. |
|
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|
2721 |
|
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|
2722 The analysis of a grammar proceeds in four stages. In |
|
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|
2723 the first, the input grammar is analyzed and a number |
|
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David A. Holland
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|
2724 of tables are built which describe all of the |
|
13d2b8934445
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|
2725 �production�s and components of the �grammar�. |
|
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parents:
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|
2726 |
|
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|
2727 In the second stage, AnaGram analyzes all of the |
|
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diff
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|
2728 character sets defined in the grammar, and where |
|
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parents:
diff
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|
2729 necessary, defines auxiliary tokens and productions. |
|
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|
2730 |
|
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|
2731 In the third stage, AnaGram identifies all of the |
|
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parents:
diff
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|
2732 states of the parser and builds the go-to table for the |
|
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David A. Holland
parents:
diff
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|
2733 parser. |
|
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|
2734 |
|
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|
2735 In the fourth stage, Anagram identifies �reduction |
|
13d2b8934445
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David A. Holland
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|
2736 tokens� for each completed �grammar rule� in each state |
|
13d2b8934445
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|
2737 and checks for �conflict�s. |
|
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|
2738 |
|
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|
2739 Use the �Analyze Grammar� command to cause AnaGram to |
|
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|
2740 analyze your grammar. |
|
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David A. Holland
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|
2741 ## |
|
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|
2742 |
|
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|
2743 Grammar Is Ambiguous |
|
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|
2744 |
|
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|
2745 This �warning� message appears if your �grammar� |
|
13d2b8934445
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|
2746 contains �conflict�s. AnaGram will resolve �shift-reduce |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2747 conflicts� by selecting the shift option. It will |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
2748 resolve �reduce-reduce conflicts� by selecting from the |
|
13d2b8934445
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|
2749 conflicting �grammar rule�s the one which appears first |
|
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|
2750 in the �syntax file�. |
|
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David A. Holland
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|
2751 ## |
|
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|
2752 |
|
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|
2753 Grammar Rule |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2754 |
|
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|
2755 A "grammar rule" is the right hand side of a production. |
|
13d2b8934445
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parents:
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|
2756 It is a sequence of �rule elements�. Each rule element |
|
13d2b8934445
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|
2757 identifies some token, which can be either a �terminal |
|
13d2b8934445
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|
2758 token� or �nonterminal token�. |
|
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|
2759 |
|
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|
2760 A grammar rule is "matched" by a |
|
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|
2761 corresponding sequence of tokens in the input stream to |
|
13d2b8934445
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parents:
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|
2762 the parser. The rule elements in the grammar rule may be |
|
13d2b8934445
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|
2763 �token name�s, �set expressions�, �character constants�, |
|
13d2b8934445
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|
2764 �immediate action�s, �keyword strings�, or �virtual |
|
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|
2765 productions�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2766 |
|
13d2b8934445
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|
2767 A grammar rule may be followed by an |
|
13d2b8934445
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|
2768 optional �reduction procedure�. The �semantic values� of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2769 the tokens that comprise the rule may be passed to the |
|
13d2b8934445
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David A. Holland
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diff
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|
2770 reduction procedure by using �parameter assignments�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
2771 |
|
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David A. Holland
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|
2772 A grammar rule always makes up the right hand side of a |
|
13d2b8934445
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diff
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|
2773 production. The left hand side of the production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2774 identifies one or more �nonterminal tokens�, or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2775 �reduction tokens�, to which the rule reduces when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2776 matched. If there is more than one reduction token, |
|
13d2b8934445
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David A. Holland
parents:
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|
2777 the production is called a �semantically determined production� and |
|
13d2b8934445
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David A. Holland
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|
2778 there should be a �reduction procedure� to select |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2779 the correct reduction token at run time. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2780 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2781 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
2782 Grammar Token |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
2783 |
|
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|
2784 The "grammar token" �configuration parameter� may be |
|
13d2b8934445
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David A. Holland
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|
2785 used to specify the �goal�, or "start" token for the |
|
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|
2786 syntax analyzer portion of AnaGram. Alternatively, you |
|
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David A. Holland
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|
2787 could simply call the token "grammar", or you could |
|
13d2b8934445
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|
2788 append a '$' character to it when you define it. |
|
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|
2789 |
|
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|
2790 Each grammar must have a grammar token specified before |
|
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|
2791 it can be analyzed or before a parser can be built. The |
|
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|
2792 grammar token is the single token to which the grammar |
|
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|
2793 finally condenses. When this token is identified by the |
|
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|
2794 parser, the parse is complete. |
|
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|
2795 ## |
|
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|
2796 |
|
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|
2797 Grammar Trace |
|
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|
2798 |
|
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|
2799 AnaGram's Grammar Trace facility lets you examine the workings of your |
|
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|
2800 �parser� in detail. You can use the Grammar Trace as soon as you have |
|
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|
2801 analyzed your �grammar�, even before you have written any �reduction |
|
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|
2802 procedure�s or other code. Thus you can defer writing procedural code |
|
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|
2803 until you have the grammar working to your specifications. |
|
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|
2804 |
|
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|
2805 Select the �Grammar Trace Window� |
|
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|
2806 from the �Action Menu� or click on the Grammar Trace |
|
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|
2807 button. |
|
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|
2808 |
|
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|
2809 In the �Parser Stack pane� you can see a representation of the |
|
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|
2810 �parser state stack� and �parser state� as they might appear in the |
|
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|
2811 course of execution of your �parser�. The �Rule Stack pane� shows the |
|
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|
2812 relationship between the contents of the parser stack and your |
|
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|
2813 �grammar�. If your grammar uses �semantically determined |
|
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|
2814 productions�, you can select the appropriate �reduction token� from |
|
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|
2815 the �Reduction Choices pane�. |
|
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|
2816 |
|
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|
2817 At any stage, the �Parser Stack� represents a parse |
|
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|
2818 in progress. It shows the sequence of �token�s that have |
|
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|
2819 been input so far and the states in which they were |
|
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changeset
|
2820 seen. When a production is complete and the grammar rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2821 is reduced, the tokens that make up the rule are removed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2822 from the stack and replaced by the token on the left |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2823 side of the production. Initially, the Parser Stack contains |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2824 only a �lookahead line�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2825 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2826 To explore your grammar, choose �token�s one by one from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2827 the �Allowable Input� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2828 pane. This pane shows the tokens allowable at the current state of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2829 grammar, and the actions that result when the tokens are chosen. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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changeset
|
2830 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2831 You can also enter text characters directly in the �text entry� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2832 field. This means you can run a Grammar Trace like a �File Trace� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2833 where the test file is replaced by the characters you type in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2834 text entry field. This is a very convenient way to check out your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2835 grammar. Text entry is, of course, not appropriate for grammars that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2836 expect �token input�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2837 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2838 In a �File Trace� you can advance the parse no matter which pane is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2839 active. In a Grammar Trace there is a question as to whether input is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2840 intended to come from the Allowable Input pane or the text entry |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2841 field. Therefore the parse can only be advanced when one of these |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2842 two is active to indicate that it is the source of input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2843 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2844 Specialized prebuilt Grammar Traces such as the �Conflict Trace� and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2845 the �Auxiliary Trace� can be selected from �Auxiliary Windows� popup |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2846 menus where appropriate. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2847 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2848 All Grammar Trace activity updates the �trace coverage� counts. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2849 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2850 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2851 Text Entry |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2852 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2853 It is sometimes more convenient to enter text in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2854 text entry box on the �Grammar Trace� toolbar than to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2855 select individual tokens from the �Allowable Input pane�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2856 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2857 By entering text you can proceed quickly to a troublesome |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2858 state without having to choose each individual token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2859 en route. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2860 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2861 After entering text, press Enter or click on the Proceed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2862 button to parse the text. Click on the single step button |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2863 to work slowly through the text step by step. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2864 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2865 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2866 header file name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2867 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2868 The "header file name" parameter names the �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2869 header� file that AnaGram will generate when it builds |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2870 your parser. This header file can be used with your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2871 parser or with other modules in your program. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2872 header file contains a number of typedef statements and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2873 an number of macro definitions which are needed in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2874 parser and may be useful in other modules. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2875 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2876 If the value of this parameter contains a '#' character, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2877 AnaGram will substitute the name of your syntax file for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2878 the '#'. The default value of "header file name" is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2879 "#.h". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2880 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2881 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2882 Help, Using Help |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2883 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2884 There are 3 main ways to access AnaGram Online Help: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2885 Press F1 for context-sensitive help from most windows and menu items. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2886 Similarly, use the �Help Cursor� from most windows and menu items. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
2887 From the Help menu, you can bring up �Help Topics� and choose a topic. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2888 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2889 You can also get fly-over help for the toolbar buttons on the �Control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2890 Panel�. File and Grammar Traces have a Help button. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2891 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2892 AnaGram's Help windows, unlike most others, remain on-screen until you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2893 dismiss them. This means you can refer to several topics at once. They |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2894 have hypertext links to other Help topics. Also, right-clicking |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2895 the mouse on a Help window or pressing F1 will pop up an Auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2896 Windows menu of all linked topics in the window. "Using Help" is always |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2897 available from this popup menu. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2898 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2899 Note that, for the �Warnings�, �Configuration Parameter�s and �Help |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2900 Topics� windows, F1 will give you help for the item |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2901 on the highlighted line, whereas the Help Cursor allows you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2902 to select any line by clicking on it. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2903 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2904 AnaGram also has documentation in HTML format, indexed in the index.html |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2905 file. This documentation covers Getting Started, examples, and some |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2906 further topics mainly condensed from the User's Guide. Hard copy |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2907 documentation is in the AnaGram User's Guide, which has the most |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2908 detail. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2909 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2910 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2911 Hidden |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2912 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2913 In a �configuration section� of your grammar you may use |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2914 an �attribute statement� to declare one or more tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2915 to be "hidden". Tokens that are "hidden" do not appear |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2916 in the �token names� table, and thus do not appear in syntax error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2917 diagnoses. When your parser attempts to determine the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2918 �error frame� of a �syntax error�, it will disregard the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2919 tokens that have been declared hidden. The hidden |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2920 declaration consists simply of the keyword hidden |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2921 followed by a list of tokens, separated by commas and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2922 enclosed in braces ({ }): |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2923 [ hidden { widget, wombat, foo, bar } ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2924 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2925 You would use the "hidden" attribute primarily for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2926 tokens whose name would not mean anything to your users. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2927 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2928 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2929 Immediate Action |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2930 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2931 Immediate actions are snippets of C code which are to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2932 be executed in the middle of a �grammar rule�. Immediate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2933 actions are denoted by a '!' character followed by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2934 either a C expression, terminated by a semicolon; or a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2935 block of C code enclosed in braces. For example, in a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2936 simple desk calculator example one might write the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2937 following: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2938 transaction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2939 -> !printf('#');, expression:x =printf("%d\n",x); |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2940 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2941 Notice that the only apparent difference between an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2942 immediate action and a �reduction procedure� is that the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2943 immediate action is preceded by '!' instead of '='. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2944 Notice that the immediate action must be followed by a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2945 comma to separate it from the following �rule element�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2946 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2947 Immediate actions may also be used in �definition�s: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2948 prompt = !printf('#'); |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2949 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2950 The above example, using this definition would then be: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2951 transaction |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2952 -> prompt, expression:x =printf("%d\n",x); |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2953 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2954 You could accomplish the same result by writing a �null |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2955 production� and a reduction procedure: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2956 prompt |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2957 -> =printf('#'); |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2958 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2959 This is exactly how AnaGram implements immediate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2960 actions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2961 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2962 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2963 Implementation Errors |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2964 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2965 "Implementation errors" are errors your parser detects |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2966 which are not the immediate result of bad input. When |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2967 it encounters an implementation error, your parser will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2968 call a macro which you can define to deal with the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2969 problem in a manner suitable to your needs. If you don't |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2970 provide these macros, AnaGram will make default |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2971 definitions. There are two macros corresponding to two |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2972 implementation errors: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2973 �PARSER_STACK_OVERFLOW� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2974 �REDUCTION_TOKEN_ERROR� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2975 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2976 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2977 Inappropriate Value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2978 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2979 This �warning� message appears when the value assigned to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2980 a �configuration parameter� is not appropriate to that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2981 parameter. Check the definition of the parameter, by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2982 opening the �Configuration Parameters Window�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2983 selecting the parameter and pressing F1. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2984 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2985 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2986 Initializer |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2987 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2988 For every �parser� it generates, AnaGram generates an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2989 "initializer" function to call the parser. AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2990 names the initializer by prefixing the �parser name� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2991 with "init_". If your parser is �event driven�, you must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2992 call the initializer before you call the parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2993 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2994 If your parser is not event driven, AnaGram will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2995 normally include a call to the initializer in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2996 parser. If you wish to be able to call your parser more |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2997 than once without its being re-initialized, you may turn |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2998 off the �auto init� �configuration switch�. When you do |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
2999 this, you assume responsibility for calling the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3000 initializer. If your parser is event driven, you must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3001 always call the initializer function. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3002 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3003 If the �reentrant parser� switch is set, the initializer takes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3004 a pointer to the �parser control block� as its sole argument. Otherwise |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3005 it takes no arguments. The initializer returns no value. All |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3006 communication is by means of the �parser control block�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3007 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3008 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3009 Input Character |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3010 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3011 The actual unit of �parser input� is usually a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3012 single character. Note that you are not limited to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3013 eight-bit characters. Your parser will use the input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3014 character to index a translation table, �ag_tcv�, to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3015 determine the �token number� for that character. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3016 �token number� identifies the actual syntactic token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3017 The character code itself will be the �semantic value� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3018 of the token. Note that AnaGram groups together all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3019 input characters that are syntactically |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3020 indistinguishable into a single input token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3021 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3022 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3023 input_code |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3024 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3025 input_code is a field in the �parser control block� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3026 which contains the current �input character�, or, if your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3027 �GET_INPUT� macro supplies �token number�s directly, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3028 token number. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3029 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3030 If you write your own �GET_INPUT� macro, you must make |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3031 sure that you store the input character, or token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3032 number, you get into �PCB�.input_code. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3033 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3034 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3035 INPUT_CODE(t) |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3036 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3037 If you set both the �pointer input� and the �input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3038 values� �configuration parameter�s, you must provide an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3039 INPUT_CODE macro for your parser. In this situation, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3040 your parser will use the pointer to load the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3041 �input_value� field of the �parser control block� and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3042 uses the INPUT_CODE macro to extract the appropriate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3043 value for the �input_code� field. For example, if the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3044 input_value is a structure and the appropriate member |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3045 field is called "id" you would write: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3046 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3047 #define INPUT_CODE(t) (t).id |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3048 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3049 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3050 input_context |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3051 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3052 "input_context" is a field which AnaGram adds to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3053 definition of the �parser control block� structure when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3054 you define a �context type� �configuration parameter�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3055 If you choose, you can write your GET_INPUT macro so |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3056 that it stores the context value in �PCB�.input_context. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3057 The default definition for �GET_CONTEXT� will then stack |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3058 the context value at the appropriate time. You can think |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3059 of PCB.input_context as a sort of temporary "parking |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3060 place" for the context value. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3061 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3062 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3063 Input Scan Aborted |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3064 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3065 This �warning� message appears if AnaGram is unable to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3066 finish scanning your �syntax file� because of previous |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3067 errors. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3068 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3069 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3070 input values |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3071 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3072 "Input values" is a �configuration switch� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3073 defaults to off. If your �parser input� includes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3074 explicit �token value�s which are not simply the ascii |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3075 values of corresponding ascii input characters, you must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3076 set the "input values" switch to inform AnaGram. Unless |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3077 your parser is �event driven� or uses �pointer input�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3078 you must also provide your own �GET_INPUT� macro. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3079 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3080 If your parser uses pointer input, you must provide an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3081 �INPUT_CODE(t)� macro. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3082 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3083 The semantic value of an input token is to be stored in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3084 �input_value� field of the parser control block. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3085 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3086 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
3087 input_value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3088 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3089 input_value is a field in the �parser control block� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3090 which is used to store the semantic value of the input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3091 token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3092 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3093 If you write your own �GET_INPUT� macro, and you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3094 set the �input values� �configuration switch�, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3095 should make sure that you store the value of the �input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3096 character� or token into �PCB�.input_value. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3097 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3098 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3099 Internal Error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3100 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3101 "AnaGram internal error: ..." is a �warning� message which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3102 appears if one of AnaGram's internal consistency tests |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3103 fails. This message should never appear if AnaGram is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3104 working properly. Usually AnaGram will abort on |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3105 encountering an internal error, although under |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3106 a small set of circumstances it may continue. Should |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3107 this happen, it would be wise to close AnaGram and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3108 restart it. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3109 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3110 If you do get an internal error, please note the complete |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3111 message identifing the problem and file a bug report, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3112 following the directions posted on the AnaGram web page |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3113 at http://www.parsifalsoft.com. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3114 A copy of the relevant |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3115 syntax file and a summary of the circumstances surrounding |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3116 the problem would be greatly appreciated. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3117 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3118 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3119 Intersection |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3120 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3121 In set theory, the intersection of two sets, A and B, is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3122 defined to be the set of all elements of A which are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3123 also elements of B. In an AnaGram �syntax file�, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3124 intersection of two �character sets� is represented with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3125 the '&' operator. The intersection operator has lower |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3126 �precedence� than the �complement� operator, but higher |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3127 precedence than the �union� and �difference� operators. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3128 The intersection operator is �left associative�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3129 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3130 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3131 Keyboard Support |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3132 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3133 AnaGram can be controlled entirely from the keyboard. In the Control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3134 Panel, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3135 can tab to any button and press Enter to select it. In addition to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3136 the conventional |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3137 Windows keyboard functions, the following keys have been implemented: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3138 Escape closes any AnaGram window except the Control Panel. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3139 F8 toggles between an active AnaGram window and the Control Panel |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3140 F10 accesses the Control Panel menu from any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3141 AnaGram Window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3142 Shift F10 pops up the Auxiliary Windows menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3143 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
3144 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3145 Keyword, Keyword String |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3146 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3147 Keywords are a very important feature of AnaGram. They |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3148 provide an easy way to pick up special character |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3149 sequences in your input, thereby eliminating the need |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3150 for a lot of tedious �production�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3151 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3152 If AnaGram finds, on the right hand side of one of your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3153 �grammar� productions, a string enclosed in double |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3154 quotes, such as "IF", it automatically creates from the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3155 string a "keyword" which is incorporated into your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3156 parser. You may have any number of keywords. A keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3157 is treated as a single terminal token. Recognition of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3158 keywords is governed by the �case sensitive� switch. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3159 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3160 Your parser will look for a keyword in its input stream |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3161 wherever you have defined this particular keyword to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3162 legitimate input. It will do whatever lookahead is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3163 necessary in order to pick up the entire keyword. If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3164 several keywords match the input, such as IF and IFF, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3165 it will select the longest match, IFF in this example. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3166 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3167 Important points to notice about keywords: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3168 1) Keywords take precedence over ordinary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3169 characters in the input stream - thus if the character |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3170 I and the keyword IF are both legitimate input at some |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3171 point, IF will be selected, if present, in preference |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3172 to I. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3173 2) Keywords are not reserved words. Your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3174 will only look for a keyword when it is in a state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3175 where that keyword is legitimate input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3176 3) Keywords do not participate in character sets |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3177 and should not appear in definitions of character sets. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3178 In particular, they are not considered as belonging to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3179 the complement of a character set. Thus |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3180 a keyword would not be considered legitimate input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3181 for the production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3182 next char -> ~( '/' + '*' ) |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3183 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3184 4) Keywords may appear in virtual productions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3185 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3186 5) Keywords may be named by means of a definition. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3187 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3188 AnaGram will list all the keywords in your grammar in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3189 the �Keywords� window. In addition, in numerous |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3190 windows where the cursor bar selects a state, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3191 �Auxiliary Windows� popup menu will list a Keywords option. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3192 This window will provide a list of the keywords |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3193 acceptable in the selected �parser state�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3194 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3195 On occasion, a kind of conflict, called a �keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3196 anomaly� may occur. If so, such conflicts will be listed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3197 in the �Keyword Anomalies� window. The "�sticky�" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3198 �attribute statement� is useful in dealing with keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3199 anomalies. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3200 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3201 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3202 Keyword Anomalies Found |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3203 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3204 This �warning� message indicates that AnaGram has found |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3205 at least one �keyword anomaly� in your �grammar�. Open |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3206 the �Keyword Anomalies� window to see a list of those |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3207 that have been found. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3208 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3209 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3210 Keyword Anomaly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3211 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3212 In �syntax directed parsing�, it is assumed that input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3213 �token�s can be uniquely identified. In the case of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3214 �keyword�s, however, there is the possibility that the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3215 individual characters making up the keyword, as well as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3216 the keyword taken as a whole, could constitute |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3217 legitimate input under some circumstances. Thus |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3218 �keywords�, though a powerful and useful tool, are not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3219 completely consistent with the assumptions that underlie |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3220 �syntax directed parsing�. This can occasionally give |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3221 rise to a type of conflict, diagnosed by AnaGram, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3222 called a "keyword anomaly". AnaGram is quite |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3223 conservative in its diagnoses, so that many keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3224 anomalies it reports are actually innocuous and can be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3225 safely ignored. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3226 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3227 Basically, a keyword anomaly is a situation where a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3228 keyword is recognized, causes a reduction, and the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3229 parser arrives in a state where the keyword is not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3230 legal input. If the keyword, seen simply as a sequence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3231 of characters, might have been legal input in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3232 original state, AnaGram notes the existence of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3233 keyword anomaly. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3234 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3235 If you have a keyword that causes a keyword anomaly and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3236 it is actually a reserved word in your grammar, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3237 anomaly is by definition innocuous. You should use the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3238 �reserve keywords� statement to inform AnaGram that the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3239 keyword is reserved and the anomaly need not be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3240 diagnosed. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3241 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3242 To help identify and correct any problems associated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3243 with keyword anomalies, AnaGram provides the �Keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3244 Anomalies� window to identify the anomalies, and the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3245 �Keyword Anomaly Trace� to help you understand a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3246 particular anomaly. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3247 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3248 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3249 Keyword Anomaly Trace |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3250 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3251 A Keyword Anomaly Trace is a ready made �grammar trace� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3252 window which you may select from the �Auxiliary Windows� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3253 menu of the �Keyword Anomalies� window. The anomaly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3254 trace provides a path to a state which illustrates the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3255 �keyword anomaly�. In this state, the keyword is a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3256 reducing token, but after the reduction, it is not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3257 allowable input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3258 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3259 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3260 Keyword Anomalies |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3261 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3262 The Keyword Anomalies window is available only if your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3263 grammar has �keyword� anomalies. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3264 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3265 Each entry in the Keyword Anomalies window consists of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3266 two lines. The first line identifies the �parser state� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3267 at which the �keyword anomaly� occurs and the offending |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3268 keyword. The second line identifies the �grammar rule� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3269 which the keyword may erroneously reduce. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3270 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3271 The �Auxiliary Windows� menu provides three auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3272 windows keyed directly to the anomaly to help you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3273 determine the nature of the problem: The �Keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3274 Anomaly Trace� window, the �Reduction Trace� window, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3275 the �Rule Derivation� window. Three other windows provide |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3276 supporting information: the �Reduction States� window, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3277 the �Rule Context� window and the �State Definition� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3278 window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3279 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3280 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3281 Keywords |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3282 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3283 The Keywords entry in the �Browse Menu� pops up a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3284 window which lists all of the keywords defined in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3285 �grammar�. The �token number� is also specified. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3286 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3287 A Keywords window is also an option in the �Auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3288 Windows� popup menu for any window which distinguishes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3289 various states of your parser. The Keywords window will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3290 show all of the �keyword�s which will be recognized in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3291 the state selected by the cursor bar in the parent |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3292 window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3293 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3294 The �Auxiliary Windows� menu for a Keywords window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3295 provides a �Token Usage� option which will allow you to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3296 all the uses of a particular keyword in your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3297 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3298 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3299 left |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3300 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3301 "left" controls a �precedence declaration�, indicating |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3302 that all of the listed �rule elements� are to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3303 considered �left associative�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3304 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3305 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3306 Left Associative |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3307 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3308 A binary operator is said to be left associative if |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3309 an expression with repeated instances of the operator |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3310 is to be evaluated from the left. Thus, for example, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3311 x = a/b/c |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3312 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3313 is normally taken to mean x = (a/b)/c The division |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3314 operator is said to be left associative. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3315 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3316 In �grammar�s with �conflict�s, you may use �precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3317 declaration�s to specify that an operator should be left |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3318 associative. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3319 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3320 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3321 Lexeme |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3322 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3323 The "lexeme" �attribute statement� is used to fine-tune |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3324 the "�disregard�" statement. The lexeme statement takes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3325 the form: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3326 lexeme { T1, T2,....Tn } |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3327 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3328 where T1,...Tn is a list of �nonterminal� tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3329 separated by commas. Lexeme statements may be placed in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3330 any �configuration section�, and there may be any number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3331 of them. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3332 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3333 When you specify that a �token� is to be disregarded, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3334 AnaGram rewrites your �grammar� so that the token will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3335 passed over whenever it occurs at the beginning of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3336 file or following a lexical unit, or "lexeme". If you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3337 have no lexeme statement, then the lexemes in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3338 grammar are just the terminal tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3339 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3340 The lexeme statement allows you to specify that certain |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3341 nonterminal tokens are also to be treated as lexemes. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3342 This means that the disregard token will be skipped |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3343 following the lexeme, but not between the characters |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3344 that constitute the lexeme. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3345 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3346 Lexemes correspond to the tokens that a lexical scanner, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3347 if you were using one, would commonly identify and pass |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3348 to a parser as single tokens. You don't usually wish to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3349 disregard �white space� within these tokens. For |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3350 example, in a grammar for a conventional programming |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3351 language where blank characters are to be disregarded, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3352 you might include: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3353 [ |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3354 lexeme {string, character constant, name, number} |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3355 ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3356 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3357 since blank characters must not be overlooked within |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3358 strings and constants, and should not be permitted |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3359 within names or numbers. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3360 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3361 If your grammar allows for situations where successive |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3362 lexemes could run together if they were not separated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3363 by space, a name followed by a number, for example, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3364 may use the "�distinguish lexemes�" �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3365 switch� to force a separation between the tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3366 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3367 White space may be used explicitly within definitions of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3368 lexeme tokens in your grammar if desired, without |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3369 causing conflicts. Thus, if you wish to allow embedded |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3370 space in variable names, you might write: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3371 [ |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3372 disregard space |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3373 lexeme {variable name} |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3374 ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3375 space = ' ' + '\t' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3376 letter = 'a-z' + 'A-Z' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3377 digit = '0-9' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3378 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3379 variable name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3380 -> letter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3381 -> variable name, letter + digit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3382 -> variable name, space..., letter + digit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3383 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3384 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3385 line |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3386 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3387 line is a field in your �parser control block� used for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3388 keeping track of the line number of the current |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3389 character in your input. Line and column numbers are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3390 tracked only if the �lines and columns� �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3391 switch� has been set. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3392 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3393 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3394 line length |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3395 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3396 Line length is an �obsolete configuration parameter�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3397 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3398 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3399 Line Numbers |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3400 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3401 "Line numbers" is a �configuration switch� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3402 defaults to off. If it is on, the �Build Parser� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3403 command will put "#line" directives into the generated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3404 C code file so that your compiler diagnostics will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3405 refer to lines in the �syntax file� rather than in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3406 generated C code file. For more information on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3407 "#line" directive, see Kernighan and Ritchie, second |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3408 edition, section A12.6. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3409 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3410 If the "line numbers" switch is off, AnaGram will put |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3411 comments into your parser file to help you find |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3412 reduction procedures and embedded C in your syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3413 file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3414 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3415 Prior to AnaGram 2.01, if your C or C++ compiler required that the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3416 backslashes in the pathname in the #line directive be doubled, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3417 would have used AnaGram's �escape backslashes� switch to make this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3418 happen. Although you may still use �escape backslashes�, it should no |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3419 longer be necessary because AnaGram now puts forward slashes into #line |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3420 pathnames instead of backslashes. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3421 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3422 If you wish, you may specify the pathname in the #line |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3423 directives explicitly by using the �Line Numbers Path� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3424 configuration parameter. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3425 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3426 You may also wish to change the "�parser file name�" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3427 parameter to provide a full path name for your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3428 file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3429 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3430 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3431 Line Numbers Path |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3432 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3433 "Line Numbers Path" is a �configuration parameter� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3434 which takes a string value. It defaults to NULL. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3435 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3436 When you have set the �Line Numbers� �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3437 switch� and Line Numbers Path is not NULL, AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3438 uses it in the #line directive in place of the full |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3439 path name of your �syntax file�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3440 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3441 Note that Line Numbers Path should be the complete |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3442 pathname for your syntax file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3443 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3444 Line Numbers Path is useful when using AnaGram in cross |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3445 platform development. When parsers are to be compiled |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3446 and tested on a platform different from that used to run |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3447 AnaGram, you may use Line Numbers Path to provide a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3448 pathname on the platform used for compiling and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3449 testing. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3450 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3451 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3452 Lines and Columns |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3453 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3454 "Lines and columns" is a �configuration switch� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3455 defaults to on. When set, i.e., on, it causes the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3456 �Build Parser� command to incorporate code into your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3457 parser which will automatically track the line number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3458 and column number of the input token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3459 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3460 You would normally set the "lines and columns" switch |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3461 when you are planning to build a parser which will read |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3462 an input file and which will need to diagnose �syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3463 errors� with some precision. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3464 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3465 Your parser will store the line and column numbers in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3466 the �line� and �column� fields respectively in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3467 �parser control block�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3468 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3469 If the input to your parser includes tab characters, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3470 should either set the �tab spacing� �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3471 parameter� appropriately or provide a �TAB_SPACING� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3472 macro for your parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3473 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3474 Your parser will count line and column numbers beginning |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3475 with one. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3476 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3477 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3478 Main Program |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3479 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3480 The "main program" �configuration switch� determines |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3481 what AnaGram does if you invoke the �Build Parser� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3482 command, but have no �embedded C� in your �syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3483 file�. If the switch is on and you have not specified |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3484 �pointer input� or an �event driven� parser, AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3485 creates a main program which does nothing but call your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3486 �parser�. The "main program" switch defaults to on. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3487 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3488 This feature, along with the default definitions for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3489 �GET_INPUT� and �error handling�, makes it possible |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3490 to write a grammar with no �embedded C� or �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3491 procedure�s whatsoever and still get an executable |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3492 program which will read input from stdin and parse it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3493 according to your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3494 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3495 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3496 Marked Rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3497 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3498 A "marked rule" is a �grammar rule� together with a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3499 marked token that indicates how much of the rule has already |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3500 been matched. The �marked token� and any tokens following it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3501 indicate the input that should be expected if the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3502 remainder of the rule is to be matched. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3503 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3504 When marked rules are displayed in AnaGram windows, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3505 marked token is represented by a difference in the font. The token may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3506 be in bold face, underlined, italicized, shown with a different point |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3507 size, or in a different font altogether. Since AnaGram allows you to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3508 change fonts to suit your own preferences, you should be careful that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3509 the font you choose for the marked tokens allows them to be readily |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3510 distinguished from the other tokens in your grammar rules. An |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3511 underlined font is often suitable. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3512 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3513 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3514 Max conflicts |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3515 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3516 The "max conflicts" �configuration parameter� limits the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3517 number of �conflict�s AnaGram will record. Sometimes, a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3518 simple error editing your syntax file can cause hundreds |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3519 of conflicts, which you don't need to see in gory |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3520 detail. The default value of max conflicts is 50. If you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3521 have a grammar that is in serious trouble and you want |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3522 to see more conflicts, you may change max conflicts to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3523 suit your needs. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3524 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3525 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3526 Missing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3527 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3528 The �warning� message Missing <element 1> in <element 2> |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3529 indicates that AnaGram expects to see an instance of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3530 syntactic element 1 at the specified location, internal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3531 to an instance of syntactic element 2. AnaGram cannot |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3532 reliably continue parsing its input after an error of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3533 this type. Therefore, it limits further analysis of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3534 your grammar to scanning for syntax errors. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3535 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3536 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3537 Missing Production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3538 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3539 "Missing production, TXXX: <token name>" is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3540 message which indicates that the specified �token� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3541 appears to be defined recursively, but there is no |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3542 initial �production� to get the recursion started. If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3543 you get this warning, check your �grammar� closely. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3544 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3545 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3546 Missing Reduction Procedure |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3547 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3548 "Missing reduction procedure, RXXX" is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3549 message which appears either when the �grammar rule� indicated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3550 specifies a �parameter assignment� but does not have a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3551 �reduction procedure� to use it, or when the rule has no reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3552 procedure but the value of the token on the left hand side is used in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3553 as an argument for some other reduction procedure and the �default reduction value� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3554 does not have the same type as the token on the left hand side. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3555 In this latter case, a reduction procedure may be needed to effect |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3556 correct type conversion. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3557 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3558 This warning is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3559 provided in case the lack of a reduction procedure is an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3560 oversight. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3561 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3562 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3563 Multiple Definitions |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3564 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3565 "Multiple definitions for TXXX: <token name>" is a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3566 �warning� message which indicates that the specified |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3567 �token� has been defined both as a �character set� and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3568 as a �nonterminal token�. It cannot be both. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3569 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3570 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3571 Near Functions |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3572 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3573 "Near Functions" is a �configuration switch� that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3574 defaults to off. It controls the use of the "near" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3575 keyword for static functions in your parser. If your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3576 parser is to run on an 80x86 processor you might wish |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3577 to turn it on. Your parser will then be a slight bit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3578 smaller and will run a little bit faster. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3579 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3580 If you are going to run your parser on some other |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3581 processor or use a C or C++ compiler that does not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3582 support the "near" keyword you should make sure "near |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3583 functions" is set to off. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3584 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3585 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3586 Negative Character Code in Pointer Mode |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3587 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3588 This �warning� message appears if your �grammar� defines |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3589 negative character codes and uses �pointer input�. If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3590 your grammar uses the default definition for �pointer |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3591 type� it will be reading unsigned characters so that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3592 the parser will never see the negative codes that have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3593 been defined. You may correct the problem by providing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3594 your own definition of pointer type. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3595 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3596 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3597 Nest Comments |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3598 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3599 "Nest comments" is a �configuration switch� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3600 defaults to off. It controls the treatment of �comments� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3601 while scanning your �syntax file�. It defaults to off, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3602 in accordance with the ANSI standard for C which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3603 disallows �nested comments�. Note that AnaGram scans |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3604 comments in any �embedded C� code as well as in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3605 grammar specification. You may turn this switch on and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3606 off as many times as necessary in a single file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3607 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3608 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3609 Nested Comment |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3610 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3611 As delivered, AnaGram treats C style �comments� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3612 according to the ANSI standard: They do not nest. For |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3613 those who prefer nested comments, however, the �nest |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3614 comments� �configuration switch� allows them to nest. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3615 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3616 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3617 Nesting too deep |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3618 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3619 This �warning� message indicates that �set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3620 expression�s or �virtual productions� are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3621 nested so deeply they have exhausted the available |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3622 stack space and AnaGram cannot continue its analysis. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3623 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3624 Use a �definition� statement to name an intermediate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3625 level. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3626 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3627 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3628 no cr |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3629 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3630 "no cr" is a �configuration switch� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3631 defaults to off. When this switch is set, it will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3632 cause the �parser file� and �header file� to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3633 written without carriage returns. This is convenient |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3634 if you wish to use the generated parser files in a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3635 Unix environment. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3636 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3637 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3638 No Grammar Token Specified |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3639 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3640 This �warning� message appears if your �grammar� does not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3641 specify a �grammar token�. Edit your �syntax file� to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3642 specify one. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3643 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3644 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3645 No Productions in Syntax File |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3646 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3647 This �warning� message appears if AnaGram did not find |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3648 any �productions� at all in your �syntax file�. Check |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3649 to see you have the right file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3650 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3651 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3652 No Such Parameter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3653 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3654 This �warning� message appears when AnaGram does not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3655 recognize the name of a �configuration parameter� you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3656 have tried to set in your �syntax file�. Check the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3657 spelling of the parameter you wish to set in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3658 �Configuration Parameters Window�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3659 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3660 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3661 No Terminal Tokens in Expansion |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3662 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3663 No terminal tokens in expansion of TXXX is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3664 message indicating that there are no terminal tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3665 to be found in an expansion of the specified token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3666 Although there are a few circumstances where this could |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3667 be legitimate, it is more likely that there is a missing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3668 rule in the grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3669 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3670 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3671 Not a Character Set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3672 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3673 "Not a character set, TXXX: <token name>" is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3674 message which indicates that the specified �token� has |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3675 been used both on the left side of a �production� and in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3676 a �character set� expression defining some other token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3677 AnaGram will use an empty set in place of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3678 specified token in evaluating the �character set�. You |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3679 will get another warning, �Error defining� token, when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3680 AnaGram finishes its evaluation of the character set. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3681 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3682 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3683 Nothing Reduces |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3684 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3685 "Nothing reduces TXXX -> RYYY" is a �warning� message |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3686 which indicates that the �grammar� does not specify any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3687 input to follow an instance of the indicated �grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3688 rule�. In all probability, the grammar does not have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3689 any explicit end of file, or �eof token�. If the grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3690 does not have any conflicts with �token� T000, then an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3691 explicit end of file indicator is not necessary. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3692 Otherwise you should modify your grammar to require an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3693 explicit end of file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3694 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3695 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3696 Null Character in String |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3697 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3698 This �warning� message appears when AnaGram finds an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3699 explicit null character in a quoted string. If you must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3700 allow for a null in a �keyword string� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3701 you will have to rewrite your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3702 �grammar rule�. For instance, instead of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3703 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3704 widget |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3705 -> "abc\0def" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3706 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3707 write |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3708 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3709 widget |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3710 -> "abc", 0, "def" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3711 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3712 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3713 nonassoc |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3714 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3715 "nonassoc" controls a �precedence declaration�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3716 indicating that all of the listed �rule elements� are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3717 to be considered non-associative. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3718 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3719 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3720 Nonterminal Token, Nonterminal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3721 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3722 A nonterminal token is one which is constructed from a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3723 series of other tokens as specified by one or more |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3724 �production�s. Nonterminal tokens are to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3725 distinguished from �terminal token�s, which are the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3726 basic input units appearing in your input stream. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3727 Terminal tokens most often represent single characters |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3728 or a character belonging to a �character set� such as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3729 'a-z'. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3730 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3731 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3732 Null Production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3733 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3734 A "null production" is one that has no tokens on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3735 right hand side whatsoever. Null �production�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3736 essentially are identified by the first following input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3737 token. Null productions are extremely convenient |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3738 syntactic elements when you wish to make some input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3739 optional. For example, suppose that you wish to allow an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3740 optional semicolon at some point in your grammar. You |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3741 could write the following pair of productions: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3742 optional semicolon -> | ';' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3743 Note that a null production can never follow a '|'. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3744 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3745 This could also be written on multiple lines thus: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3746 optional semicolon |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3747 -> |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3748 -> ';' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3749 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3750 You can always rewrite your grammar to eliminate null |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3751 productions if you wish, but you usually pay a price in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3752 conciseness and clarity. Sometimes, however, it is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3753 necessary to do such a rewrite in order to avoid |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3754 �conflict�s, to which null productions are especially |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3755 prone. For example suppose you have the following |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3756 production: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3757 foo -> wombat, optional semicolon, widget |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3758 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3759 You can rewrite this as two productions: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3760 foo |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3761 -> wombat, widget |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3762 -> wombat, ';', widget |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3763 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3764 This rewrite specifies exactly the same input language, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3765 but is less prone to conflicts. On the other hand, it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3766 may require significantly more table space in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3767 parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3768 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3769 If you have a null production with no �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3770 procedure� specified, your parser will automatically |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3771 assign the value zero to �reduction token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3772 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3773 Null productions can also be generated by �virtual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3774 productions�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3775 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3776 A token that has a null production is a "�zero length�" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3777 token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3778 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3779 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3780 Old Style |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3781 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3782 "Old Style" is a �configuration switch� which defaults |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3783 to off. It controls the function definitions in the code |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3784 AnaGram generates. When "old style" is off, it generates |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3785 ANSI style calling sequences with prototypes as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3786 necessary. When "old style" is on, it generates old |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3787 style function definitions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3788 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3789 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3790 Output Files |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3791 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3792 When you use the �Build Parser� command, to request |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3793 output from AnaGram, it creates two files: a �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3794 file� and a �parser header� file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3795 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3796 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3797 Page Length |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3798 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3799 "Page length" is an �obsolete configuration parameter�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3800 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3801 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3802 Obsolete Configuration Parameter, Obsolete Configuration Switch |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3803 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3804 A number of �configuration parameter�s and �configuration switch�es |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3805 which were used in the DOS version of AnaGram are no longer |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3806 used, but are still recognized for the sake of upward |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3807 compatibility. These parameters include: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3808 �bottom margin� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3809 �line length� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3810 �page length� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3811 �top margin� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3812 �quick reference� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3813 �video mode� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3814 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3815 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3816 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3817 Parameter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3818 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3819 "Parameter <name> has type void" is a �warning� message |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3820 which appears when a �parameter assignment� is attached |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3821 to a �token� that has been defined to have the void |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3822 �data type�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3823 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3824 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3825 Parameter Assignment |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3826 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3827 In any �grammar rule�, the �semantic value� of any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3828 �rule element� may be passed to a �reduction procedure� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3829 by means of a parameter assignment. Simply follow the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3830 rule element with a colon and a C variable name. The C |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3831 variable name can then be used in the reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3832 procedure to reference the semantic value of the token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3833 it is attached to. AnaGram will automatically provide |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3834 necessary declarations. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3835 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3836 Here are some examples of rule elements with parameter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3837 assignments: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3838 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3839 '0-9':d |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3840 integer:n |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3841 expression:x |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3842 declaration : declaration_descriptor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3843 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3844 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3845 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3846 Parameter Not Defined |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3847 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3848 AnaGram does not have a �configuration parameter� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3849 with the specified name. Please check the spelling. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3850 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3851 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3852 Parameter Takes Integer Value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3853 The specified �configuration parameter� takes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3854 an integer value only. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3855 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3856 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3857 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3858 Parameter Takes String Value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3859 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3860 The specified �configuration parameter� takes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3861 a string value only. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3862 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3863 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3864 Parse Function |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3865 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3866 To run your parser, you call the parse function. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3867 The name of the parse function is given by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3868 the �parser name� �configuration parameter� and defaults to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3869 name of your parser file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3870 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3871 If your parser uses �pointer input�, you should set the �pointer� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3872 field of the �parser control block� before calling the parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3873 function. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3874 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3875 If your parser is �event driven�, you should first call the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3876 �initializer�, and then you should call the parser function |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3877 for each input token you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3878 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3879 If the �reentrant parser� switch is set, the parse function takes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3880 a pointer to the �parser control block� as its sole argument. Otherwise |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3881 it takes no arguments. The parse function returns no value. All |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3882 communication is by means of the �parser control block�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3883 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3884 To retrieve the value of the �grammar token�, once the parse is complete, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3885 use the �parser value function�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3886 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3887 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3888 Parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3889 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3890 A parser is a program or, more commonly, a procedure within |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3891 a program, which scans a sequence of �input characters� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3892 or input tokens and accumulates them in an input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3893 buffer or stack as determined by a set of �production�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3894 which constitute a �grammar�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3895 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3896 When the parser discovers |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3897 a sequence of tokens as defined by a �grammar rule�, or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3898 right hand side of a production, it "reduces" the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3899 sequence to a single �reduction token� as defined by the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3900 left hand side of the grammar rule. This �nonterminal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3901 token� now replaces the tokens which matched the grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3902 rule and the search for matches continues. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3903 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3904 If an input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3905 token is encountered which will not yield a match for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3906 any rule, it is considered a �syntax error� and some |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3907 kind of �error recovery� may be required to continue. If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3908 a match, or �reduce action�, yields the �grammar token�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3909 sometimes called the �goal token� or �start token�, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3910 parser deems its work complete and returns to whatever |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3911 procedure may have called it. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3912 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3913 The �Grammar Trace� and �File Trace� functions in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3914 AnaGram provide a convenient means for understanding the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3915 detailed operation of a syntax directed parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3916 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3917 �Tokens� may have �semantic values�. If the �input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3918 values� �configuration switch� is on, your parser will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3919 expect semantic values to be provided by the input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3920 process along with the token identification code. If the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3921 input values switch is off, your parser will take the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3922 ascii value of the input character, that is, the actual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3923 input code, as the value of the character. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3924 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3925 When the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3926 parser reduces a production, it can call a �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3927 procedure� or �semantic action� to analyze the values of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3928 the constituent tokens. This reduction procedure can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3929 then return a value which characterizes the reduced |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3930 token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3931 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3932 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3933 Parser Control Block |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3934 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3935 A "Parser Control Block" is a structure which contains |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3936 all of the data necessary to describe the instantaneous |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3937 state of a parser. The typedef statement which defines |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3938 the structure is included in the �parser header� file |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3939 for your parser. AnaGram creates the name of the data |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3940 type for the structure by appending "_pcb_type" to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3941 �parser name�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3942 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3943 You may add your own declarations to the parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3944 block by using the �extend pcb� statement. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3945 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3946 If the �declare pcb� �configuration switch� is on, its |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3947 normal state, AnaGram will declare a parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3948 block for you at the beginning of your parser file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3949 AnaGram will determine the name of the parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3950 block by appending "_pcb" to the �parser name�. AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3951 will also define the macro PCB as a short hand notation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3952 for use within the parser. All references to the parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3953 control block within the code that AnaGram generates |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3954 are made using the PCB macro. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3955 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3956 If you wish to declare your own parser control block, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3957 you must include the �parser header� file for your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3958 parser before your declaration. Then you declare a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3959 control block and define PCB to refer to the control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3960 block you have declared. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3961 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3962 Suppose your grammar is called widget. You would then |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3963 write the following statements in your �embedded C�: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3964 #include "widget.h" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3965 widget_pcb_type widget_control_pcb; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3966 #define PCB widget_control_pcb |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3967 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3968 Alternatively, you could write the following: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3969 #include "widget.h" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3970 widget_pcb_type *widget_control_pcb_pointer; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3971 #define PCB (*widget_control_pcb) |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3972 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3973 and then allocate storage for the structure when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3974 necessary. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3975 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3976 Some fields of interest in the parser control block are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3977 as follows: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3978 �input_code� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3979 �input_value� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3980 �input_context� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3981 �pointer� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3982 �token_number� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3983 �reduction_token� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3984 �ssx� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3985 �sn� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3986 �ss�[�parser stack size�] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3987 �vs�[parser stack size]; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3988 �cs�[parser stack size]; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3989 �line� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3990 �column� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3991 *�error_message� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3992 �error_frame_ssx� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3993 �error_frame_token� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3994 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3995 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3996 PCB |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3997 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3998 "PCB" is a macro AnaGram defines for use in the code it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
3999 generates to refer to the �parser control block� for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4000 your �parser�. Normally, AnaGram automatically declares |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4001 storage for a parser control block and defines PCB for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4002 you. If you turn off the �declare PCB� switch, you may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4003 define PCB yourself. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4004 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4005 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4006 PCB_TYPE |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4007 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4008 If you are writing your parser in C++, you may prefer to derive |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4009 a class from the �parser control block� rather than use the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4010 �extend pcb� statement. In this case you may define the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4011 PCB_TYPE macro in your syntax file to specify your derived |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4012 class. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4013 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4014 For instance, you have defined |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4015 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4016 class MyPcb : public parser_pcb_type {...}; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4017 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4018 You would then add the following line: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4019 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4020 #define PCB_TYPE MyPcb |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4021 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4022 If you do not define PCB_TYPE, AnaGram will define it as the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4023 type of your parser control block. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4024 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4025 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4026 Parser File |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4027 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4028 The "parser file" is the C (or C++) file output by AnaGram when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4029 you execute the �Build Parser� command. It contains all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4030 of the �embedded C� from your �syntax file�, all of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4031 �reduction procedure�s defined in your �grammar�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4032 syntax tables which represent, in a condensed form, all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4033 of the intricacies of your grammar, and a customized |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4034 �parsing engine�. The name of the parser file is given |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4035 by the �parser file name� �configuration parameter�. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4036 name of the �parser� itself is given by the �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4037 name� configuration parameter. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4038 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4039 If you wish the parser file to be written without carriage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4040 returns, suitable for a Unix environment, set the �no cr� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4041 configuration switch. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4042 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4043 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4044 Parser File Name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4045 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4046 "Parser file name" is a �configuration parameter� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4047 takes a string value. The default value is "#.c". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4048 AnaGram uses this parameter to generate the name of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4049 output C file, or �parser file�, created by the �Build |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4050 Parser� command. The '#' character is used in this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4051 string as a wild card to indicate the name of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4052 current �syntax file�. If the first character of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4053 parser file name string is a '.' character, AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4054 will substitute the name of the current working |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4055 directory for the dot. Thus ".\\#.c" will create the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4056 file name as a complete path. This can sometimes be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4057 important when using the �line numbers� switch to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4058 enable a debugger to find code in your parser file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4059 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4060 Note that the parser file name is not the same as the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4061 �parser name�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4062 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4063 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4064 Parser Generator |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4065 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4066 A parser generator, such as AnaGram, is a program that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4067 converts a �grammar�, a rule-based description of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4068 input to a program, into a conventional, procedural |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4069 module called a �parser�. The parsers AnaGram generates |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4070 are simple C modules which can be compiled on almost |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4071 any platform. AnaGram parsers are also compatible with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4072 C++. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4073 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4074 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4075 Header File, Parser Header |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4076 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4077 When you use the command �Build Parser� to generate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4078 source code for a parser, AnaGram creates two files, a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4079 header file and a C source file. Unless different |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4080 paths are specified in the �parser file name� and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4081 �header file name� parameters, both files will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4082 written to the directory that contains the �syntax file�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4083 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4084 The header file contains a number of typedef statements, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4085 including the definition of the �parser control block�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4086 and a number of macro |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4087 definitions which may be useful in your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4088 or in other modules of your program. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4089 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4090 If you do not alter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4091 the �header file name� parameter, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4092 name of the header file will be the same as the name of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4093 your �syntax file� and it will have the extension ".h". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4094 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4095 If you wish the header file to be written without carriage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4096 returns, suitable for a Unix environment, set the �no cr� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4097 configuration switch. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4098 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4099 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4100 Parser Input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4101 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4102 AnaGram �parser�s may be configured to accept input in any of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4103 three different ways: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4104 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4105 By default, a �parse function� gets its input by invoking the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4106 �GET_INPUT� macro each time it is ready for another input token. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4107 default implementation of GET_INPUT reads �input character�s from stdin. For |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4108 most practical problems, you will want to override this definition of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4109 GET_INPUT, storing the current input character in PCB.input_code. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4110 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4111 Alternatively, you may configure a parser to read input from an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4112 array in memory. Set the �pointer input� switch and load the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4113 �pointer� field of the parser control block before calling the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4114 parse function. The parser will then run, incrementing the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4115 pointer, until it finishes or encounters an error. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4116 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4117 The third alternative is to set the �event driven� switch. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4118 parser will be configured as a callback routine. Begin by calling |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4119 the �initializer�. Then, for each input character, store the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4120 character in the �input_code� field of the parser control block and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4121 call the parse function. Each time |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4122 you call the parse function it will continue until it needs more |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4123 input. You can check its status by inspecting the �exit_flag� in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4124 parser control block. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4125 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4126 The input to your parser may be either text characters or �tokens� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4127 accumulated by a pre-processor, or �lexical scanner�. The latter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4128 case is referred to as �token input�. If you use a lexical scanner, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4129 you may find it convenient to configure your parser as event driven. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4130 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4131 Altlhough lexical scanners are often not necessary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4132 when you use AnaGram, if you do need one you can write it in AnaGram. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4133 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4134 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4135 Parser Name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4136 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4137 "Parser Name" is a �configuration parameter� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4138 defaults to "#", where "#" represents the name of your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4139 �syntax file�. AnaGram uses this parameter to name your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4140 �parse function�. The �initializer� for your parser will have the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4141 same name preceded by "init_". Note that "�parser file |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4142 name�" is not the same configuration parameter as "parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4143 name". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4144 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4145 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4146 Parser Stack |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4147 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4148 Your �parser� uses a "parser stack" to keep track of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4149 �grammar rules� it is trying to match and its progress |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4150 in matching them. Normally, there are two separate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4151 stacks defined by AnaGram: �PCB�.�ss�, the �parser state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4152 stack� which maintains �parser state� numbers, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4153 PCB.�vs�, the �parser value stack� which maintains the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4154 �semantic value�s of tokens that have been identified so |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4155 far. If you wish to maintain a stack tracking other |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4156 variables you may set the �context type� �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4157 parameter�, and AnaGram will define a third stack, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4158 PCB.�cs�. All are indexed by the same stack index, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4159 PCB.�ssx�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4160 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4161 To see how tokens accumulate on the parser stack, run |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4162 the �Grammar Trace� or the �File Trace�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4163 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4164 Normally, when the return value of a �reduction procedure� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4165 is stored on the parser value stack, it is stored by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4166 simply coercing the stack pointer to the correct type. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4167 If the return value is a C++ object, this can cause |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4168 serious problems. These problems can be avoided by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4169 using the �wrapper� statement. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4170 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4171 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4172 Parser stack alignment |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4173 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4174 Parser stack alignment is a �configuration parameter� whose |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4175 value is a C or C++ data type. It defaults to "long". If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4176 any tokens have type "double", it will be automatically set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4177 to double. Thus, you will normally not need to change this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4178 parameter if your parser is to run on a PC or compatible |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4179 processor. It provides alignment control for processors |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4180 which restrict address for multibyte data access. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4181 default setting provides for correct operation on 64 bit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4182 processors. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
4183 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4184 To control byte alignment of the parser stack, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4185 �PCB�.�vs�, AnaGram normally adds a field of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4186 specified data type to the "union" statement which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4187 defines the data type for the �parser stack�. This |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4188 parameter can be used to deal with byte alignment |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4189 problems when a �parser� is to be run on a processor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4190 with byte alignment restrictions. For instance, if your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4191 �grammar� has �token�s of type "long double" and your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4192 processor requires long double variables to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4193 properly aligned, you can include the following |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4194 statement in a �configuration section� in your grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4195 or in your �configuration file�: |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4196 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4197 parser stack alignment = long double |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4198 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4199 If the data type specified is "void", no alignment declaration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4200 will be made. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4201 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4202 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4203 Parser Stack Index, Stack Index |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4204 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
4205 The parser stack index, �PCB�.�ssx�, tracks the depth |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4206 of the �parser state stack�, the �parser value stack�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4207 and the �context stack� if you defined one. The parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4208 stack index is incremented by �shift actions� and |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4209 reduced by �reduce actions�. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4210 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
4211 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4212 Parser Stack Overflow |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
4213 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
4214 Your �parser� uses a �parser stack� to keep track of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4215 �grammar rules� it is trying to match and its progress |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4216 in matching them. If your grammar has any �recursive |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
4217 rule�s that are not strictly left recursive, then no |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4218 matter how big you make the parser stack, it will be |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4219 possible to create a syntactically correct input which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4220 will cause the stack to overflow. As a practical matter, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4221 however, it is usually possible to set the �parser stack |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4222 size� to a value large enough so that an overflow is a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4223 freak occurrence. Nevertheless, it is necessary to check |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4224 for overflow, and in the case overflow should occur, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4225 your parser has to do something. What it does is invoke |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4226 the �PARSER_STACK_OVERFLOW� macro. If you don't define |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4227 it, AnaGram will define it for you, although not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4228 necessarily to your taste. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4229 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
4230 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4231 Recursive rule, Recursion |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4232 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4233 A �grammar rule� is said to be "recursive" if the �token� on the left side |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4234 of the rule also appears on the right side of the rule, or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4235 in an �expansion rule� of any token on the right side of the rule. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4236 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4237 If the token on the left side is the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4238 first token on the right side, the rule is said to be "left recursive". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4239 If it is the last token on the right side, the rule is said to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4240 "right recursive". Otherwise, the rule is "center recursive". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4241 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
4242 For example: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4243 statement list |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4244 -> statement |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4245 -> statement list, statement // left recursive |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4246 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4247 fraction part |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4248 -> digit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4249 -> fraction part, digit // right recursive |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4250 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4251 expression |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4252 -> factor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4253 -> expression, '+' + '-', factor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4254 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4255 factor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4256 -> primary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4257 -> factor, '*' + '/', primary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4258 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4259 primary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4260 -> number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4261 -> name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4262 -> '(', expression, ')' // center recursive |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4263 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4264 Note that if all the tokens in the rule other then the recursive token itself |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4265 are �zero length� tokens, it is possible for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4266 rule to be matched arbitrarily many times without any input whatsoever. In |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4267 other words, such a rule creates an infinite loop in the parser. AnaGram can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4268 detect this condition and issues an �empty recursion� diagnostic if it occurs. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4269 |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
4270 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
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|
4271 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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diff
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|
4272 PARSER_STACK_OVERFLOW |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4273 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4274 PARSER_STACK_OVERFLOW is a user definable macro. If you |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
4275 do not define it, AnaGram will define it so that it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
4276 will print a message on stderr and abort the �parser� in |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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|
4277 case of a �parser stack overflow�. |
|
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David A. Holland
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|
4278 ## |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
4279 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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|
4280 Parser Stack Size |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
4281 |
|
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diff
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|
4282 "Parser stack size" is a �configuration parameter� with |
|
13d2b8934445
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diff
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|
4283 a default value of 128. It is used to define the sizes |
|
13d2b8934445
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David A. Holland
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diff
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|
4284 of your �parser stacks� in your �parser control block�. |
|
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|
4285 When analyzing your grammar, AnaGram will determine the |
|
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Import AnaGram (near-)release tree into Mercurial.
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diff
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|
4286 minimum amount of stack space required for the deepest |
|
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Import AnaGram (near-)release tree into Mercurial.
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|
4287 left �recursion�. To this depth it will add one half the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4288 value of the parser stack size parameter. It will then |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
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diff
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|
4289 set the actual stack size to the larger of this value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4290 and the parser stack size parameter. |
|
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David A. Holland
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|
4291 ## |
|
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|
4292 |
|
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|
4293 Parser State, State Number |
|
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|
4294 |
|
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|
4295 The essential part of your �parser� is a group of tables |
|
13d2b8934445
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diff
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|
4296 which describe in detail what to do for each "state" of |
|
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|
4297 the parser. |
|
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diff
changeset
|
4298 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4299 The states of a parser are determined by sets of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4300 "�characteristic rules�". The �State Definition Table� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4301 shows the characteristic rules for each state of your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4302 parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4303 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4304 AnaGram numbers the states of a parser as it identifies |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4305 them, beginning with zero. In all windows, state numbers |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4306 are displayed as three digit numbers prefixed with the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4307 letter 'S'. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4308 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4309 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4310 Parser State Stack, State Stack |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4311 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4312 The parser state stack is a stack maintained by your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4313 �parser� and which is an integral part of the parsing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4314 process. At any point in the parse of your input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4315 stream, the parser state stack provides a summary of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4316 what has been found so far. The parser state stack is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4317 stored in �PCB�.�ss� and is indexed by PCB.�ssx�, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4318 �parser stack index�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4319 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4320 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4321 Parser Value Stack, Value Stack |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4322 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4323 In parallel with the �parser state stack�, your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4324 maintains a "value stack", �PCB�.�vs�, each entry of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4325 which corresponds to the �semantic value� of the token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4326 identified at that state. Since the semantic values of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4327 different tokens might well have different �data type�s, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4328 AnaGram gives you the opportunity, in your �syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4329 file�, to define the data type for any token. AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4330 then builds a typedef statement creating a data type |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4331 which is a union of the all the types you have defined. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4332 AnaGram creates the name for this �data type� by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4333 appending "_vs_type" to the �parser name�. AnaGram uses |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4334 this data type to define the value stack. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4335 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4336 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4337 Parser Action |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4338 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4339 In a traditional LR parser, there are only four actions: the �shift |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4340 action�, the �reduce action�, the �accept action� and the �error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4341 action�. AnaGram, in doing its �grammar analysis�, identifies a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4342 number of special cases, and creates a number of extra actions which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4343 make for faster processing, but which can be represented as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4344 combinations of these primitive actions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4345 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4346 When a shift action is performed, the current state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4347 number is pushed onto the �parser state stack� and the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4348 new state number is determined by the current state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4349 number and the current input token. Different tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4350 cause different new states. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4351 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4352 When a reduce action is performed, the length of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4353 rule being reduced is subtracted from the �parser stack |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4354 index� and the new state number is read from the top of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4355 the parser state stack. The �reduction token� for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4356 rule being reduced is then used as an input token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4357 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4358 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4359 Parsing Engine |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4360 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4361 A parser consists of three basic components: A set of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4362 syntax tables, a set of �reduction procedure�s and a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4363 parsing engine. The parsing engine is the body of code |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4364 that interprets the parsing table, invokes input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4365 functions, and calls the reduction procedures. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4366 �Build Parser� command configures a parsing engine |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4367 according to the implicit requirements of the syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4368 specification and according to the explicit values of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4369 the �configuration parameter�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4370 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4371 The parsing engine itself is a simple automaton, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4372 characterized by a set of states and a set of inputs. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4373 The inputs are the tokens of your grammar. Each state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4374 is represented by a list of tokens which are admissible |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4375 in that state and for each token a �parser action� to perform |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4376 and a parameter which further defines the action. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4377 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4378 Each state in the grammar, with the exception of state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4379 zero, has a �characteristic token� which must have been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4380 recognized in order to jump to that state. Therefore, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4381 the �parser state stack�, which is essentially a list |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4382 of state numbers, can also be thought of as a list of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4383 token numbers. This is the list of tokens that have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4384 been seen so far in the parse of your input stream. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4385 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4386 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4387 Partition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4388 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4389 If you use �character sets� in your grammar, AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4390 will compute a "partition" of the �character universe�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4391 This partition is a collection of non-overlapping |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4392 character sets such that every one of the sets you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4393 defined can be written as a �union� of partition sets. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4394 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4395 Each partition set is assigned a unique �token�. If one |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4396 of your character sets requires more than one partition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4397 set to represent it, AnaGram will create appropriate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4398 �production�s and add them to your grammar so your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4399 can make the necessary distinctions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4400 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4401 To see how AnaGram has partitioned the character |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4402 universe, you may inspect the �Partition Sets� window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4403 found in the �Browse Menu�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4404 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4405 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4406 Partition Set Number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4407 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4408 Each �partition� set is identified by a unique |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4409 reference number called the partition set number. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4410 Partition set numbers are displayed in the form Pxxx. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4411 Partition sets are numbered starting with zero, so the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4412 first set is P000. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4413 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4414 To see the elements of a given partition set, call up |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4415 the �Partition Sets� window from the �Browse Menu�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4416 then, after selecting a partition set, call up the �Set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4417 Elements� window from the �Auxiliary Windows� popup menu. |
|
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Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4418 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4419 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4420 Partition Sets |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4421 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4422 The Partition Sets option in the �Browse Menu� pops up |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4423 a window which shows the complete �partition� of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
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parents:
diff
changeset
|
4424 �character universe� for your parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4425 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
4426 The Partition Sets option in the �Auxiliary Windows� popup menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4427 for the �Character Sets� window lets you see the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4428 partition sets which cover the specified character set. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4429 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4430 Each entry in a Partition Sets window identifies a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4431 token number and a �partition set number�. The �Auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4432 Windows� menu provides a �Set Elements� entry which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4433 enables you to see precisely which characters belong to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4434 the partition set. It also has a Token Usage entry to show you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4435 what rules the set is used in. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4436 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4437 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4438 PCONTEXT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4439 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4440 PCONTEXT is an alternate form of the �CONTEXT� macro |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4441 which takes an explicit argument to specify the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4442 �parser control block�. PCONTEXT is defined in the �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4443 header� file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4444 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4445 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4446 PERROR_CONTEXT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4447 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4448 PERROR_CONTEXT is an alternative form of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4449 �ERROR_CONTEXT� macro. It differs only in that it takes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4450 an argument so you can specify the appropriate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4451 �parser control block� explicitly. PERROR_CONTEXT is defined in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4452 the �parser header� file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4453 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4454 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4455 pointer |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4456 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4457 "pointer" is a field which will be included in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4458 �parser control block� for your parser if you have set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4459 the �pointer input� �configuration switch�. Your main |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4460 program should set PCB.pointer before it calls your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4461 parser. Thereafter, your parser will increment it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4462 appropriately. When you are executing a �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4463 procedure� or a �SYNTAX_ERROR� macro PCB.pointer will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4464 always point to the next input character to be read. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4465 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4466 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4467 Pointer input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4468 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4469 "Pointer input" is a �configuration switch� which you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4470 may set to control �parser input�. It defaults to off. When you set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4471 pointer input, you tell AnaGram that the input to your parser is in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4472 memory and can be scanned simply by incrementing a pointer. Before |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4473 calling your parser you should make sure that �PCB�.�pointer� is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4474 properly initialized to point to the first character or token in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4475 input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4476 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4477 Use the �configuration parameter� "�pointer type�" to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4478 specify the type of the pointer. The default value of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4479 "pointer type" is "unsigned char *" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4480 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4481 There is no particular reason why pointer type should |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4482 be limited to variants on char. It could define a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4483 pointer to int or a structure just as well. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4484 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4485 If you use pointer input with structures or C++ |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4486 classes, you should set the �input values� switch and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4487 define an �INPUT_CODE�(t) macro. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4488 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4489 If you are using a 16 bit compiler and your input array |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4490 is so large that you need "huge" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4491 pointers, make sure that "pointer type" is properly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4492 defined. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4493 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4494 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4495 Pointer Type |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4496 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4497 "Pointer Type is a �configuration parameter� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4498 defaults to "unsigned char *". When you have specified |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4499 �pointer input�, AnaGram uses the value of pointer type |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4500 to declare a pointer field in your �parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4501 block�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4502 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4503 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4504 Precedence, Operator Precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4505 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4506 In expressions of the form a+b*c, the convention is to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4507 perform the multiplication before the addition. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4508 Multiplication is said to take precedence over |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4509 addition. In general the rank order in which operations |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4510 are to be performed if there are no parentheses forcing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4511 an order of computation is called the precedence of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4512 operators. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4513 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4514 If you have an ambiguous �grammar�, that is, a grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4515 with a number of �conflict�s, you may use �precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4516 declaration�s to resolve the conflicts and to set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4517 operator precedence. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4518 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4519 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4520 Precedence Declaration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4521 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4522 Precedence declarations are �attribute statements� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4523 may be used to resolve �conflict�s in your grammar by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4524 assigning precedence and associativity to operators. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4525 Precedence declarations must be made inside |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4526 �configuration sections�. Each declaration consists of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4527 the keyword �left�, �right�, or �nonassoc� followed by a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4528 list of �rule elements�. The rule elements in the list |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4529 must be separated by commas and the entire list must be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4530 enclosed in braces ({ }). |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4531 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4532 Each of the rule elements is assigned the same |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4533 precedence level, which is higher than that assigned in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4534 all previous precedence declarations and lower than that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4535 in all subsequent declarations. The rule elements are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4536 defined to be left, right, or nonassociative, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4537 depending on whether the keyword was "left", "right", or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4538 "nonassoc". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4539 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4540 All conflicts which are resolved by precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4541 declarations are listed in the �Resolved Conflicts� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4542 window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4543 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4544 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4545 Precedence Rules |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4546 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4547 AnaGram can resolve certain types of �conflict�s in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4548 grammar by applying precedence rules. There are three |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4549 classes of rules available: explicit �precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4550 declarations�, the "�sticky�" statement, and the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4551 implicit rule associated with the use of a "�disregard�" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4552 token outside a �lexeme�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4553 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4554 Whenever AnaGram uses a precedence rule of any kind to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4555 resolve a conflict, it produces a �warning� message and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4556 lists the conflict in the �Resolved Conflicts� window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4557 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4558 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4559 Previous States |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4560 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4561 The Previous States window can be accessed via the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4562 �Auxiliary Windows� popup menu from any window that identifies |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4563 �parser state�s. It shows the �characteristic rule�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4564 for all of the states which jump to the presently |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4565 selected state. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4566 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4567 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4568 Print File Name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4569 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4570 "Print file name" is a configuration parameter which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4571 is not used in the Windows version of AnaGram. It is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4572 retained only for compatibility with pre-existing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4573 �configuration file�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4574 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4575 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4576 Problem States |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4577 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4578 The Problem States window is essentially a trimmed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4579 version of the �Reduction States� window. It is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4580 available in the �Auxiliary Windows� popup menu for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4581 �Conflicts� and �Resolved Conflicts� windows. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4582 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4583 The Problem States window has the same format as the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4584 Reduction States window, and differs only in that it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4585 shows only those reduction states for which the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4586 �conflict token� is acceptable input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4587 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4588 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4589 Production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4590 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4591 Productions are the mechanism you use to describe how |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4592 complex input structures are built up out of simpler |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4593 ones. Each production has a left hand side and a right |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4594 hand side. The right hand side, or �grammar rule�, is a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4595 sequence of �rule elements�, which may represent either |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4596 �terminal tokens� or �nonterminal tokens�. The left |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4597 hand side is a list of �reduction tokens�. In most |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4598 cases there would be only a single reduction token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4599 Productions with more than one �token� on the left hand |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4600 side are called �semantically determined productions�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4601 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4602 The "->" symbol is used to separate the left hand side |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4603 from the right hand side. If you have several |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4604 productions with the same left hand side, you can avoid |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4605 rewriting the left hand side either by using '|' or by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4606 using another "->". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4607 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4608 A �null production�, or empty right hand side, cannot |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4609 follow a '|'. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4610 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4611 Productions may be written thus: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4612 name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4613 -> letter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4614 -> name, digit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4615 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4616 This could also be written |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4617 name -> letter | name, digit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4618 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4619 In order to accommodate semantic analysis of the data, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4620 you may attach to any grammar rule a �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4621 procedure� which will be executed when the rule is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4622 identified. Each token may have a �semantic value�. By |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4623 using �parameter assignment�s, you may provide the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4624 reduction procedure with access to the semantic values of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4625 tokens that comprise the grammar rule. When it finishes, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4626 reduction procedure may return a value which will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4627 saved on the �parser value stack� as the semantic value of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4628 �reduction token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4629 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4630 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4631 Productions |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4632 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4633 The �Production�s window is available via the �Auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4634 Windows� popup menu in any window which identifies tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4635 If the token identified by the highlighted line is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4636 �nonterminal�, the Productions window will show the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4637 rules produced by that �token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4638 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4639 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4640 PRULE_CONTEXT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4641 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4642 PRULE_CONTEXT is an alternative form of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4643 �RULE_CONTEXT� macro. It differs only in that it takes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4644 an argument so you can specify the appropriate �parser control block� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4645 explicitly. PRULE_CONTEXT is defined in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4646 the �parser header� file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4647 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4648 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4649 Quick Reference |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4650 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4651 "Quick reference" is an �obsolete configuration switch�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4652 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4653 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4654 Range Bounds Out of Order |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4655 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4656 This is a �warning� message that appears when you have a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4657 �character range� of the form 'z-a'. AnaGram interprets |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4658 this range as being equal to 'a-z', but provides a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4659 warning in case the unusual order was the result of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4660 clerical error. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4661 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4662 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4663 Recursive Definition of Char Set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4664 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4665 This �warning� appears when AnaGram discovers a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4666 recursively defined �character set�. Character sets |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4667 cannot be defined recursively. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4668 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4669 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4670 Redefinition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4671 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4672 "Redefinition of <name>" is a �warning� message which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4673 appears when AnaGram discovers a redefinition of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4674 �symbol�. The new �definition� is ignored. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4675 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4676 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4677 Redefinition of Grammar Token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4678 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4679 This �warning� appears when AnaGram encounters a new |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4680 definition of the �grammar token�. AnaGram discards the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4681 old definition. The last definition in the syntax file |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4682 wins. If you get this warning, check your �syntax file� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4683 to make sure you have the grammar token you want. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4684 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4685 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4686 Redefinition of token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4687 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4688 "Redefinition of token, TXXX: <name>" is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4689 message which occurs when AnaGram encounters a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4690 �definition� statement and the specified �grammar token� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4691 has already been seen on the left side of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4692 �production�. AnaGram will ignore the definition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4693 statement. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4694 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4695 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4696 Reduce Action, Reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4697 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4698 The reduce action, or reduction, is one of the four |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4699 actions of a traditional �parsing engine�. The reduce |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4700 action is performed when the parser has succeeded in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4701 matching all the elements of a �grammar rule�, and the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4702 next input token is not erroneous. Reducing the grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4703 rule amounts to subtracting the length of the rule from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4704 the �parser stack index�, identifying the �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4705 token�, stacking its �semantic value� and then doing a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4706 �shift action� with the reduction token as though it had |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4707 been input directly. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4708 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4709 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4710 Reduce-Reduce Conflict |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4711 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4712 A grammar has a "reduce-reduce" �conflict� at some |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4713 state if a single token turns out to be a �reducing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4714 token� for more than one �completed rule�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4715 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4716 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4717 Reducing Token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4718 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4719 In a �parser state� with more than one �completed rule�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4720 your parser must be able to determine which one was |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4721 actually found. Therefore, during analysis of your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4722 grammar, AnaGram examines each completed rule in order |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4723 to determine all the states the �parser� will branch to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4724 once the rule is reduced. These states are called the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4725 "reduction states" for the rule. In any window that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4726 displays �marked rule�s, these states may be found in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4727 the �Reduction States� window listed in the �Auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4728 Windows� popup menu. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4729 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4730 The acceptable input tokens for those states are the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4731 "reducing tokens" for the completed rules in the state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4732 under investigation. If there is a single token which is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4733 a reducing token for more than one rule, then the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4734 grammar is said to have a �reduce-reduce conflict� at |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4735 that state. If in a particular state there is both a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4736 �shift action� and a �reduce action� for the same token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4737 the grammar is said to have a �shift-reduce conflict� in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4738 that state. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4739 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4740 Note that a "reducing token" is not the same as a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4741 "�reduction token�". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4742 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4743 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4744 Reduction Choices |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4745 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4746 "Reduction choices" is a �configuration switch� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4747 defaults to off. If it is set, AnaGram will include in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4748 your �parser file� a function which will identify the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4749 acceptable choices for �reduction token� in the current |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4750 state. This function, of course, is useful only if you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4751 are using �semantically determined productions�. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4752 prototype of this function is: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4753 int $_reduction_choices(int *); |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4754 where '$' represents the name of your parser. You must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4755 provide an integer array whose length is at least as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4756 long as the maximum number of reduction choices you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4757 might have. The function will fill the array with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4758 the token numbers of those which are acceptable in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4759 current state and will return a count of the number of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4760 acceptable choices it found. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4761 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4762 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4763 reduction_token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4764 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4765 "reduction_token" is a field in your �parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4766 block�. If your grammar uses �semantically determined |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4767 productions�, your �reduction procedure�s need a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4768 mechanism to specify which token the rule is to reduce |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4769 to. �PCB�.reduction_token names the variable which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4770 contains the �token number� of the �reduction token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4771 Prior to calling your reduction procedure, your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4772 will set this field to the token number of the default |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4773 �reduction token�, i.e., the leftmost syntactically correct token in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4774 reduction token list for the production being reduced. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4775 If the reduction procedure establishes that a different |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4776 reduction token is appropriate, it should store the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4777 appropriate token number in PCB.reduction_token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4778 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4779 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4780 Reduction Procedures |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4781 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4782 The Reduction Procedures window lists the C function |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4783 prototypes for the �reduction procedure�s in your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4784 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4785 When this window is active, the �syntax file� window, if |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4786 visible, is synchronized with it so you can see the body of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4787 the reduction procedure as well as its usage. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4788 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4789 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4790 REDUCTION_TOKEN_ERROR |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4791 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4792 REDUCTION_TOKEN_ERROR is a user definable macro which your �parser� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4793 invokes when it encounters an inadmissible reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4794 token. This error should occur only if your parser uses |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4795 �semantically determined productions� and your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4796 �reduction procedure� provides an incorrect �token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4797 number�. If you do not define it, AnaGram will define |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4798 it so that it will print an error message on stderr and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4799 abort the parse. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4800 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4801 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4802 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4803 Reduction Procedure, Semantic Action |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4804 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4805 A "reduction procedure", or "semantic action", is a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4806 function you write which your �parser� executes when it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4807 has identified the grammar rule to which the reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4808 procedure is attached in your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4809 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4810 When your parser has identified a particular �grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4811 rule�, that is to say, a particular sequence of �tokens� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4812 that you have specified in your grammar, it "reduces" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4813 the production to the token at the head of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4814 production, or �reduction token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4815 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4816 If you choose, you can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4817 specify a "reduction procedure" which your parser will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4818 call so that your program can do semantic analysis on |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4819 the production just identified. Your reduction procedure |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4820 will be called using, as arguments, the �semantic |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4821 values� of tokens on the right side of the production. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4822 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4823 Your reduction procedure may, if you choose, return a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4824 value which will become the semantic value of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4825 reduction token. Since many of the tokens in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4826 �production�s are there for only syntactic purposes, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4827 may specify, when you write your grammar, the tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4828 whose values are needed as arguments for your reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4829 procedure. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4830 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4831 To attach a reduction procedure to a grammar rule, just |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4832 write it immediately following the rule. There |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4833 are two formats for reduction procedures, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4834 depending on the size and complexity of the procedure. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4835 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4836 The first form consists of an equal sign followed by a C |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4837 expression and a semicolon. When the rule is matched the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4838 expression will be evaluated and its value will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4839 stacked on the �parser value stack� as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4840 the value of the reduction token. For example: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4841 =-a; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4842 =myProcedure(x, q); |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4843 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4844 The second form consists of an equal sign followed by a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4845 block of C code enclosed in curly braces. If you wish to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4846 return a value for the reduction token you have to use a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4847 return statement. For example: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4848 ={ |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4849 if (x > y) return x; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4850 return x+2y; |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4851 } |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4852 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4853 In both forms of the reduction procedure, �parameter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4854 assignment�s may be attached to �rule element�s in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4855 order to make their semantic values available to the reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4856 procedure. When the reduction procedure is executed, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4857 local variables |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4858 will defined with the names specified in the parameter |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4859 assignments. The values of these variables |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4860 will have been set to the value of the corresponding |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4861 token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4862 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4863 If the return value of your reduction procedure is a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4864 C++ object, you may wish to spacify that AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4865 enclose it in a �wrapper� so that constructor calls |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4866 and destructor calls are made. Otherwise the object |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4867 pushed onto and popped from the parser value stack simply by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4868 coercing the stack pointer to the appropriate type. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4869 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4870 The reduction procedures in your grammar are summarized |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4871 in the �Reduction Procedures� window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4872 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4873 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4874 Reduction States |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4875 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4876 The Reduction States window can be accessed via the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4877 �Auxiliary Windows� popup menu from any window which displays |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4878 �parser state� numbers and �marked rule�s. If the highlighted |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4879 �grammar rule� has no marked token, the Reduction States window will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4880 show the states the parse could reach by reducing the rule and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4881 processing the resultant �reduction token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4882 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4883 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4884 Reduction Token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4885 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4886 A �token� which appears on the left hand side of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4887 �production� is called a reduction token. It is so |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4888 called because when the �grammar rule� on the right side |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4889 of the production is matched in the input stream, your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4890 �parser� will "reduce" the sequence of tokens which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4891 matches the rule by replacing the sequence of tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4892 with the reduction token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4893 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4894 If more than one |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4895 reduction token is specified, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4896 the production is called a �semantically determined production� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4897 and your �reduction procedure� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4898 should choose the appropriate reduction token. If it does not, your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4899 will use the first token in the list that is syntactically |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4900 correct as the default. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4901 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4902 The �CHANGE_REDUCTION� macro can be used to specify the reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4903 token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4904 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4905 Note that a "reduction token" is not the same as a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4906 "�reducing token�". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4907 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4908 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4909 Reduction Trace |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4910 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4911 The Reduction Trace window is available from the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4912 �Conflicts� window and the �Resolved Conflicts� window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4913 It can be used in conjunction with the �Conflict Trace� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4914 to study �conflict�s. The Reduction Trace represents the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4915 result of taking the reduce option in the conflict state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4916 of the Conflict Trace. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4917 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4918 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4919 Reentrant Parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4920 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4921 "Reentrant parser" is a �configuration switch� which defaults to off. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4922 If it is on when AnaGram builds a parser AnaGram will generate code that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4923 passes the pointer to the �parser control block� via calling sequences, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4924 rather than using static references to the pcb. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4925 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4926 You can use the reentrant parser switch to help make �thread safe |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4927 parsers�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4928 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4929 The reentrant parser switch is compatible with both C and C++. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4930 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4931 The reentrant parser switch cannot be used in conjunction with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4932 the �old style� switch. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4933 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4934 When you have enabled the reentrant parser switch, the �parse function�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4935 the �initializer� function, and the �parser value function� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4936 will be defined to take a pointer to the parser control block as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4937 their sole argument. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4938 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4939 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4940 Reload Button |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4941 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4942 The �File Trace� window includes a reload button to allow |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4943 you to reread your �test file� after you have modified |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4944 it without having to start a new file trace. After the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4945 file has been reread, the file trace is reset. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4946 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4947 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4948 rename macro |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4949 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4950 AnaGram uses a number of macros in its generated code. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4951 It is possible, therefore, to run into naming |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4952 collisions with other components of your program. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4953 rename macro �attribute statement� allows you to change |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4954 the name AnaGram uses for a particular macro to avoid |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4955 these problems. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4956 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4957 For example, in the Microsoft |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4958 Foundation Classes, V4.2, there is a class called |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4959 "CONTEXT". If you use the �context stack� option in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4960 AnaGram, your �parser� will have a macro called |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4961 �CONTEXT�. To avoid the name collision, add the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4962 following attribute statement to any configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4963 section in your grammar: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4964 rename macro CONTEXT AG_CONTEXT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4965 Then, simply use "AG_CONTEXT" where you would otherwise |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4966 have used "CONTEXT". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4967 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4968 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4969 reserve keywords |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4970 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4971 "reserve keywords" is an �attribute statement� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4972 can be used to specify a list of �keyword�s that are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4973 reserved and cannot be used except as explicitly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4974 specified in the grammar. In particular this switch |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4975 enables AnaGram to avoid issuing meaningless �keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4976 anomaly� warnings. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4977 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4978 AnaGram does not automatically presume that keywords |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4979 are also reserved words, since in many grammars there |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4980 is no need to specify reserved words. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4981 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4982 Reserve keywords statements must be made inside |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4983 �configuration sections�. Each statement consists of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4984 the keyword "reserve keywords" followed by a list of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4985 keyword �tokens�. The tokens must be separated by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4986 commas and the list must be enclosed in braces ({ }). |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4987 Each keyword listed will then be treated as a reserved |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4988 word. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4989 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4990 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4991 Reset Button |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4992 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4993 The Reset button, found on �File Trace� and �Grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4994 Trace� windows restores the initial configuration of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4995 the trace. This is especially convenient for �Conflict |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4996 Trace� or other �Auxiliary Trace�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4997 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4998 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
4999 Resolved Conflicts |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5000 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5001 AnaGram creates the Resolved Conflicts window only when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5002 the grammar it is analyzing has �conflict�s and when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5003 those conflicts have been resolved by �precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5004 declaration�s, by "�sticky�" statements, or in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5005 connection with the explicit use of a token specified in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5006 a �disregard� statement. The Resolved Conflicts window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5007 shows the conflicts that have been resolved, using the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5008 same format as that of the �Conflicts� Window. The rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5009 chosen is marked with an asterisk in the leftmost column |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5010 of the window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5011 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5012 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5013 Resynchronization |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5014 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5015 "Resynchronization" is the process of getting your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5016 parser back in step with its input after encountering a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5017 �syntax error�. As such, it is one method of �error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5018 recovery�. Of course, you would resynchronize only if it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5019 is necessary to continue after the error. There are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5020 several options available when using AnaGram. You could |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5021 use the �auto resynch� option, which causes AnaGram to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5022 incorporate an automatic resynchronizing procedure into |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5023 your parser, or you could use the �error token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5024 resynchronization� option, which is similar to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5025 technique used by YACC programmers. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5026 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5027 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5028 right |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5029 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5030 "right" controls a �precedence declaration�, indicating |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5031 that all of the listed �rule elements� are to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5032 considered �right associative�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5033 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5034 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5035 Right Associative |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5036 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5037 A binary operator is said to be right associative if |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5038 an expression with repeated instances of the operator |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5039 is to be evaluated from the right. Thus, for example, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5040 when '=' is used as an assignment operator |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5041 x = a = b |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5042 is normally taken to mean a = b followed by x = a The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5043 assignment operator is said to be right associative. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5044 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5045 In �grammar�s with �conflict�s, you may use �precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5046 declaration�s to specify that an operator should be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5047 right associative. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5048 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5049 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5050 Rule Context |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5051 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5052 The Rule Context window can be accessed via the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5053 �Auxiliary Windows� menu in any window that displays |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5054 �grammar rule�s. AnaGram displays all occurrences in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5055 �grammar� of all the �reduction token�s for the rule. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5056 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5057 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5058 RULE_CONTEXT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5059 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5060 RULE_CONTEXT is a macro you may use if you have defined |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5061 a �context stack�. In any reduction procedure, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5062 RULE_CONTEXT will be a pointer to the context value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5063 stacked before the first token of the rule being |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5064 reduced. Since the context stack contains an entry for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5065 each token in the rule, you may inspect the context |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5066 value for each token in the rule by subscripting |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5067 RULE_CONTEXT. RULE_CONTEXT[k] is the context of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5068 (k-1)th token in the rule. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5069 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5070 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5071 Rule Coverage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5072 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5073 "Rule Coverage" is the name of both a �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5074 switch� and a window. The configuration switch |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5075 defaults to off. If you set it, AnaGram will include |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5076 code in your �parser� to count the number of times your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5077 parser identifies each �grammar rule� in your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5078 To maintain the counts, AnaGram declares, at the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5079 beginning of your parser, an integer array, whose name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5080 is created by appending "_nrc" to your �parser name�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5081 The array contains one counter for each rule you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5082 defined in your grammar. There are no entries for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5083 auxiliary rules that AnaGram creates to deal with set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5084 overlaps or �disregard� statements. In order to identify |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5085 positively all the rules that the parser reduces, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5086 AnaGram has to turn off certain optimization features in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5087 your parser. Therefore a parser that has rule coverage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5088 enabled will run slightly slower that one with the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5089 switch off. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5090 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5091 In addition, AnaGram creates a pair of functions to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5092 write the counters to a file and to initialize the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5093 counters from a file. The names of these functions are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5094 given by appending "_write_counts" and "_read_counts" to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5095 the name of your parser. The name of the file is given by the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5096 �coverage file name� paramater which defaults |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5097 to the name of your �syntax file� but with the extension ".nrc". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5098 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5099 If rule coverage is enabled, AnaGram will also enable the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5100 Rule Coverage option on the �Browse Menu�. If you select |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5101 Rule Coverage, AnaGram will initialize a �Rule Coverage� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5102 window from the rule count file you select. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5103 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5104 AnaGram will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5105 warn you if the rule count file is older than |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5106 the syntax file, since under those conditions, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5107 coverage file might be invalid. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5108 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5109 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5110 Rule Derivation, Token Derivation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5111 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5112 You can use the Rule Derivation and Token Derivation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5113 windows to understand the nature of �conflict�s in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5114 grammar. To create these windows, open the �Conflicts� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5115 window. Move the cursor bar to a �completed rule�, that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5116 is, one which has no marked token. Press the right mouse button to pop |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5117 up the �Auxiliary Windows� menu. You may then select the Rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5118 Derivation or the Token Derivation. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5119 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5120 The Rule Derivation window and the Token Derivation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5121 window, together, show how a �conflict�, or ambiguity, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5122 has arisen in your grammar. Both windows contain a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5123 sequence of rules, and both begin with the same rule, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5124 the rule which is the root cause of the conflict. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5125 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5126 Each subsequent line in the rule derivation is an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5127 �expansion� of the marked token in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5128 the previous rule. The last rule in the derivation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5129 window is the rule you selected in the Conflicts |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5130 window. Thus the rule derivation window shows you how |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5131 the rule involved in the conflict derives from the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5132 root. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5133 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5134 Each subsequent line in the token derivation window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5135 shows an expansion of the marked token in the previous rule. The first |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5136 token of the last rule in the derivation window is the token that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5137 causes the conflict. This is the usage that is inconsistent with other |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5138 usages of this token in the conflict state. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5139 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5140 The Rule Derivation and Token Derivation windows each |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5141 have five auxiliary windows. The �Rule Context� window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5142 is keyed to the highlighted rule. the other four |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5143 windows, the �Expansion Rules� window, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5144 �Productions� window, the �Set Elements� window and the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5145 �Token Usage� window are keyed to the marked token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5146 Remember that there is no marked token on the last |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5147 line of the Rule Derivation window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5148 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5149 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5150 Rule Element |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5151 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5152 A �grammar rule� is a list of "rule elements", separated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5153 by commas. Rule elements may be �token name�s, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5154 �character sets�, �keyword�s, �immediate action�s, or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5155 �virtual productions�. When AnaGram encounters a rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5156 element for which no token presently exists, it creates |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5157 one. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5158 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5159 Any rule element may be followed by a �parameter assignment� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5160 in order to make the �semantic value� of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5161 the rule element available to a �reduction procedure�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5162 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5163 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5164 Rule Number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5165 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5166 AnaGram assigns a unique rule number to each �grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5167 rule� that you specify in your grammar. Rules are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5168 numbered sequentially as they are encountered in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5169 �syntax file�. AnaGram constructs rule 0 itself. Rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5170 zero has a single �rule element�, the �grammar token�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5171 unless you have an �disregard� statement in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5172 grammar. In this case, there will be two elements. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5173 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5174 In AnaGram displays, rule numbers are displayed with a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5175 prefixed 'R' and a three digit decimal number. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5176 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5177 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5178 Rule Stack, Rule Stack Pane |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5179 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5180 The Rule Stack pane appears across the bottom of a �Grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5181 Trace� or �File Trace� window. It provides an alternate view of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5182 parser stack for the trace, showing, for each state, rules instead of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5183 the tokens that you see in the �Parser Stack pane�. Because it is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5184 synched with the syntax file window, the Rule Stack makes it easy to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5185 see the relationship between the trace and your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5186 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5187 For each level of the parser stack, the Rule Stack shows the �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5188 state� number and all the active rules. The active rules at any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5189 state consist of all the �expansion rule�s for the state that are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5190 consistent with the input at all subsequent states. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5191 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5192 Except for the last level |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5193 of the stack, each rule has a �marked token�, which in the default |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5194 configuration is displayed in bold, italic type. The significance of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5195 the marked token is that all tokens in the rule to the left of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5196 marked token have already been matched in the input, and the input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5197 in subsequent levels is consistent so far with the marked |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5198 token. As more input is processed, rules |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5199 that are inconsistent with the new input are deleted from the display. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5200 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5201 The last level of the stack shows the current state of the parser and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5202 the rules against which the �lookahead token� will be matched. At |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5203 this level, there may be rules with no marked tokens. These are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5204 rules which have been matched exactly in the input. If there is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5205 more than one such rule, at the next parser step the parser will use |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5206 the lookahead token to determine which rule to reduce. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5207 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5208 In the last level of the stack, marked tokens represent the input the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5209 parser expects to see. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5210 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5211 The Rule Stack pane is synched with the �syntax file� window if it is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5212 visible so that the rule highlighted in the Rule Stack can be seen |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5213 in context in the syntax file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5214 For rules that AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5215 generated automatically (to implement �virtual productions� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5216 or the �disregard� statement). the cursor bar will move to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5217 top of the syntax file window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5218 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5219 The Rule Stack pane is also synched with the other panes in the trace. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5220 As you move the cursor bar in the Rule Stack, the cursor bar in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5221 Parser Stack pane will track the stack level in the Rule Stack. In |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5222 a File Trace, text will be highlighted in the �Test File� pane |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5223 corresponding to the selected token in the Parser Stack pane. In a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5224 Grammar Trace, the marked token in the highlighted rule will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5225 highlighted in the �Allowable Input pane�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5226 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5227 Clicking the right mouse button pops up an �Auxiliary Windows� menu to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5228 give you more information about the highlighted rule. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5229 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5230 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5231 Rule Table |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5232 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5233 The Rule Table lists, in numerical order, all the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5234 �grammar rule�s defined in your �grammar�. Each rule is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5235 preceded by the �nonterminal� tokens which produce it. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5236 If you are not using �semantically determined |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5237 production�s, then there will be precisely one token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5238 line per rule. The Rule Table is synched to your �syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5239 file� to show the rule in context. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5240 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5241 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5242 Semantic Value, Token Value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5243 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5244 A �token� generally has a "semantic value", or "token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5245 value", as well as the �token number� which identifies |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5246 it syntactically. Each instance of the token in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5247 input stream can have a different value. For example, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5248 you might have a token called "variable name". In one |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5249 instance the variable name might be "widget" and in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5250 another, "wombat". Then "widget" and "wombat" would be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5251 the semantic values in the two instances. Another token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5252 might have numeric semantic values. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5253 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5254 You can specify the C or C++ �data type� of the token value. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5255 The data type of "variable name" could be "char *" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5256 where the value is a pointer to a string holding the name. There |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5257 are separate default types for the values of �terminal� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5258 and �nonterminal� tokens. In the usual case of ordinary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5259 character input, the value of a terminal token is just |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5260 the ascii character code. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5261 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5262 The value of a nonterminal token is determined by the �reduction procedure�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5263 attached to the rules the token produces. If there is no reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5264 procedure, the value of the token is the value of the first token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5265 in the rule. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5266 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5267 It should be noted that the stack operations have been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5268 implemented in such a way that a C++ object that belongs |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5269 to a class for which the assignment operator has been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5270 overridden will encounter serious problems. This shortcoming |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5271 will be addressed in a future version of AnaGram. Note that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5272 there is no problem with using a pointer to any C++ object. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5273 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5274 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5275 Semantically Determined Production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5276 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5277 A "semantically determined production" is one which has |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5278 more than one �reduction token� specified on the left |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5279 side of the �production�. You would write such a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5280 production when the reduction tokens are syntactically |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5281 indistinguishable. The �reduction procedure� may then |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5282 specify which of the listed reduction tokens the grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5283 rule is to reduce to based on semantic considerations. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5284 If there is no reduction procedure, or the reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5285 procedure does not specify a reduction token, the parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5286 will use the first syntactically correct one in the list. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5287 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5288 To simplify changing the reduction token, AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5289 provides a predefined macro, �CHANGE_REDUCTION�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5290 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5291 The �semantic value�s of all the reduction tokens for a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5292 given semantically determined production must have the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5293 same �data type�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5294 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5295 �File Trace� and �Grammar Trace� have a �Reduction Choices pane� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5296 appears when a semantically determined production is invoked and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5297 you need to choose a reduction token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5298 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5299 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5300 Set Elements |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5301 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5302 The Set Elements window is available via the �Auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5303 Windows� popup menu from windows which specify character sets, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5304 partition sets or tokens. It displays the actual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5305 characters which make up the set, or which map to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5306 specified token. For each character, the numeric code as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5307 well as its display symbol is given. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5308 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5309 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5310 Set Expression, Expression |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5311 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5312 A set expression is an algebraic expression used to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5313 define a �character set� in terms of individual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5314 characters, ranges of characters, or other sets of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5315 characters as constructed using �complements�, �unions�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5316 �intersections�, and �differences�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5317 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5318 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5319 Shift Action |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5320 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5321 The shift action is one of the four actions of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5322 traditional �parsing engine�. The shift action is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5323 performed when the input token matches one of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5324 acceptable input tokens for the current �parser state�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5325 The �semantic value� of the token and the current |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5326 �state number� are stacked, the �parser stack index� is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5327 incremented and the state number is set to a value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5328 determined by the previous state and the input token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5329 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5330 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5331 Shift-Reduce Conflict |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5332 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5333 A "shift-reduce" �conflict� occurs if in some �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5334 state� there exists a �terminal token� that should be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5335 shifted, because it is legitimate input for one of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5336 �grammar rule�s of the state, but should also be used to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5337 reduce some other rule because it is a �reducing token� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5338 for that rule. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5339 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5340 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5341 sn |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5342 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5343 sn is a field in a �parser control block� to which your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5344 �error handling� routines and your �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5345 procedure�s may refer. Its value is the current �state |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5346 number� of your �parser�. sn is modified every time |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5347 your parser "shifts" (performs a �shift action� on) a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5348 token or reduces (performs a �reduce action� on) a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5349 �production�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5350 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5351 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5352 ss |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5353 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5354 ss is a field in a �parser control block� to which your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5355 �error handling� and �reduction procedure�s may refer. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5356 It is the �state stack� for your �parser�. Before every |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5357 �shift action�, the current �state number�, �sn�, is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5358 stored in PCB.ss[PCB.ssx], where �ssx� is the �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5359 stack index�. PCB.ssx is then incremented. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5360 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5361 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5362 ssx |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5363 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5364 ssx is a field in a �parser control block� to which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5365 your �error handling� routines and �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5366 procedure�s may refer. It is the �parser stack index� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5367 for your �parser�. On every �shift action� it is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5368 incremented. On every �reduce action� the length of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5369 the �grammar rule� being reduced is subtracted from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5370 PCB.ssx. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5371 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5372 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5373 State Definition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5374 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5375 The State Definition window can be accessed via the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5376 �Auxiliary Windows� popup menu from any window that specifies |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5377 states. It displays the �characteristic rules� that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5378 define the state. The rules are displayed with a marked token, which is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5379 the next token needed in the input if the particular �grammar rule� is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5380 to be matched. If the rule is a completed rule, no token will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5381 marked. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5382 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5383 Each line contains the state number, blank if it is the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5384 same as the state number of the previous line, the �rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5385 number�, and finally the �marked rule�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5386 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5387 The �State Definition Table�, found in the �Browse |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5388 Menu�, displays the characteristic rules for all states |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5389 in the �grammar�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5390 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5391 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5392 State Definition Table |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5393 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5394 The State Definition Table lists, for each �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5395 state�, all of the �characteristic rules� which define |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5396 that state. The rules are displayed with a �marked token�, which is the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5397 next token needed in the input if the particular �grammar rule� is to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5398 be matched. If the rule is a completed rule, no token will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5399 marked. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5400 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5401 Each line contains the state number, blank if it is the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5402 same as the state number of the previous line, the �rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5403 number�, and finally the �marked rule�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5404 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5405 In the �Auxiliary Windows� menu for many states there is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5406 a �State Definition� entry which provides the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5407 characteristic rules for the �parser state� identified by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5408 the cursor bar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5409 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5410 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5411 State Expansion |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5412 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5413 The State Expansion window may be accessed using the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5414 �Auxiliary Windows� menu from any window that identifies |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5415 a particular �parser state�. It shows the complete set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5416 of �expansion rule�s for the state, consisting of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5417 union of the set of �characteristic rule�s and, for each |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5418 characteristic rule, the set of expansion rules for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5419 marked token. Thus the State |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5420 Expansion window shows all possible legal input to your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5421 parser in the given state. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5422 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5423 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5424 Sticky |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5425 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5426 "Sticky" statements are �attribute statement�s and may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5427 be used just like a �precedence declaration� to resolve |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5428 �conflict�s. If a �shift-reduce conflict� occurs in a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5429 state where the �characteristic token� is "sticky", the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5430 shift action will always be chosen. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5431 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5432 Sticky statements must be made inside �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5433 sections�. Each statement consists of the keyword |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5434 "sticky" followed by a list of �tokens�. The tokens must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5435 be separated by commas and the list must be enclosed in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5436 braces ({ }). Each token will then be treated as sticky. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5437 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5438 All conflicts which are resolved by sticky statements |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5439 are listed in the �Resolved Conflicts� window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5440 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5441 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5442 subgrammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5443 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5444 Declaring a nonterminal token to be a "subgrammar" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5445 changes the way AnaGram searches for reducing tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5446 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5447 Normally, if there is a completed rule in a particular |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5448 state, AnaGram investigates all states to which the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5449 parser could jump on reducing the rule. It then |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5450 considers all terminal tokens that are acceptable input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5451 in these states to be reducing tokens for the given |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5452 rule. If this set of tokens overlaps the set of tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5453 for which there are shift actions, or the set of tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5454 which reduce a different rule, there is a �conflict�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5455 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5456 Now consider a particular nonterminal token T and all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5457 the rules it produces, whether directly or indirectly. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5458 What the preceding remarks mean is that in determining |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5459 the reducing tokens for any of these rules, AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5460 considers not only the definition, but also the usage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5461 of T. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5462 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5463 There are circumstances when it is inappropriate to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5464 consider the usage of T. The most common example occurs |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5465 when building a lexical scanner for a language such as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5466 C. In this case, you can write a complete grammar for a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5467 C token with no difficulty. But if you try to extend it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5468 to a sequence of tokens, you get scores of conflicts. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5469 This situation arises because you specify that any C |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5470 token can follow another, when in actual practice, an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5471 identifier, for example, cannot follow another |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5472 identifier without some intervening space or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5473 punctuation. While it is theoretically possible to write |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5474 a grammar for a sequence of tokens that has no |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5475 conflicts, it is not usually pretty. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5476 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5477 The subgrammar declaration resolves this problem by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5478 telling AnaGram that when it is looking for reducing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5479 tokens for any rule produced directly or indirectly by a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5480 subgrammar token, it should disregard the usage of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5481 token and only consider usage internal to the definition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5482 of the subgrammar token, as though the subgrammar token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5483 were the start token of the grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5484 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5485 The subgrammar declaration is made in a �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5486 section� and consists of the keyword "subgrammar" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5487 followed by a list of token names separated by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5488 commas and enclosed in braces ({ }). For example: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5489 subgrammar { name, number} |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5490 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5491 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5492 Suspicious Production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5493 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5494 This �warning� message appears when AnaGram finds a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5495 �production� of the form x -> x. There is probably a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5496 typo somewhere in your �syntax file�. This production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5497 causes a �conflict� in your grammar. AnaGram leaves |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5498 this production in your �grammar�, but if you build a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5499 parser, it will never succeed in recognizing this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5500 production. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5501 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5502 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5503 Switch Takes on/off Values Only |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5504 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5505 The specified parameter is a �configuration switch�. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5506 only values it may be assigned are ON and OFF. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5507 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5508 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5509 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5510 Symbol |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5511 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5512 In writing your �grammar� you use symbols, or names, to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5513 represent most of your �tokens�. You may also use |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5514 symbols to represent �character set�s, �virtual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5515 production�s, �immediate action�s, or �keyword�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5516 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5517 A symbol, or name, must begin with a letter or an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5518 underscore. It may then contain any number of these |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5519 characters as well as digits and embedded white space |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5520 (including comments). For identification purposes all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5521 adjacent white space characters within a symbol name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5522 are considered to be a single blank. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5523 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5524 Upper case and lower case letters are considered to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5525 different. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5526 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5527 Examples: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5528 token name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5529 token/*embedded comment*/name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5530 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5531 All symbols used in your grammar are listed in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5532 the �Symbol Table� window found in the �Browse Menu�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5533 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5534 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5535 Symbol Table |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5536 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5537 The Symbol Table lists all the symbols, or names, you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5538 used in your grammar. �Symbol�s may be used, of course, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5539 to identify �tokens�, �definitions�, �virtual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5540 productions�, �immediate action�s, or �keyword�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5541 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5542 Each line in this table identifies a single symbol. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5543 first field is the token number, if any. This is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5544 followed by the name. If the name identifies an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5545 �expression� or virtual production, it is followed by an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5546 equal sign and the expression or virtual production. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5547 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5548 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5549 Syntax Analysis Aborted |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5550 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5551 This �warning� message appears if, because of previous |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5552 errors, AnaGram is unable to complete the �Analyze |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5553 Grammar� command on your �syntax file�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5554 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5555 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5556 Syntax Directed Parsing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5557 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5558 Syntax directed parsing, or formal parsing, is an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5559 approach to building �parsers� based on formal language |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5560 theory. Given a suitable description of a language, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5561 called a �grammar�, there are algorithms which can be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5562 used to create parsers for the language automatically. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5563 In this context, the set of all possible inputs to a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5564 program may be considered to constitute a language, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5565 the rules for formulating the input to the program |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5566 constitute the grammar for the language. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5567 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5568 The parsers built from a grammar have the advantage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5569 that they can recognize any input that conforms to the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5570 rules, and can reject as erroneous any input that fails |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5571 to conform. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5572 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5573 Since the program logic necessary to parse input is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5574 often extremely intricate, programs which use formal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5575 parsing are usually much more reliable than those built |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5576 by hand. They are also much easier to maintain, since |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5577 it is much easier to modify a grammar specification |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5578 than it is to modify complex program logic. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5579 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5580 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5581 Syntax Error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5582 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5583 When you specify a �grammar�, you specify a set of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5584 input character or token sequences which your �parser� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5585 will "recognize". Usually it is possible for there to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5586 be other sequences of input tokens which deviate from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5587 the rules set down by your grammar. Should your parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5588 find such a sequence in its input which is not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5589 explicitly allowed for in your grammar, it is said to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5590 have found a "syntax error". The general treatment of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5591 syntax errors is called �error handling�, of which there |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5592 are two distinct aspects: �error diagnosis� and �error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5593 recovery�. AnaGram allows you to make provision for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5594 error handling to fit your needs, but should you not do |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5595 so, it will provide simple default error handling. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5596 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5597 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5598 Statements |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5599 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5600 AnaGram source files, or �syntax file�s, consist of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5601 the following types of statements: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5602 �production�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5603 �configuration section�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5604 �embedded C� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5605 �definition�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5606 �token declaration�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5607 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5608 Statements may be in any order. Each statement must |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5609 begin on a new line. If a statement cannot be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5610 construed as complete, it may continue onto another |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5611 line. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5612 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5613 Statements may contain spaces, tabs or comments, but |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5614 may not contain blank lines. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5615 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5616 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5617 Syntax File |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5618 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5619 Input files to AnaGram are called syntax files. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5620 default extension for syntax files is .syn. A |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5621 syntax file contains a "�grammar�" and supporting C or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5622 C++ code. The file consists of several distinct types |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5623 of statements. These are �token declarations�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5624 �production�s, �definitions�, �embedded C�, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5625 �configuration sections�. There may be as many of each |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5626 as you need, in whatever order you find convenient. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5627 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5628 Each such statement begins on a new line. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5629 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5630 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5631 SYNTAX_ERROR |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5632 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5633 SYNTAX_ERROR is a macro which your parser will invoke |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5634 when it encounters a syntax error in its input stream. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5635 If you have set the �diagnose errors� �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5636 switch�, the static variable �PCB�.�syntax_error� will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5637 contain a pointer to a diagnostic message when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5638 SYNTAX_ERROR is invoked. If you have also set the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5639 �error frame� switch, �PCB�.�error_frame_ssx� and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5640 �PCB�.�error_frame_token� will also be set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5641 appropriately. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5642 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5643 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5644 Tab Spacing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5645 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5646 "tab spacing" is a �configuration parameter� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5647 controls the expansion of tabs when AnaGram displays |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5648 your source file or test files in the �File Trace� window. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5649 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5650 The value of "tab spacing" is also used to set the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5651 default value of the �TAB_SPACING� macro in your parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5652 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5653 The default value of "tab spacing" is 8. If you prefer |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5654 a different value, you should probably include an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5655 appropriate statement in your �configuration file�. For |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5656 example: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5657 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5658 tab spacing = 2 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5659 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5660 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5661 TAB_SPACING |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5662 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5663 If you have enabled the �lines and columns� switch, your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5664 parser needs to know tab spacing in order to increment |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5665 the column count when it encounters a tab character. It |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5666 is set up to use the value given by the TAB_SPACING |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5667 macro. If you do not define TAB_SPACING in your parser, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5668 AnaGram will provide a default definition, setting it to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5669 the value of the �tab spacing� �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5670 parameter�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5671 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5672 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5673 Terminal, Terminal Token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5674 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5675 A "terminal token" is a token which does not appear on |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5676 the left side of a �production�. It represents, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5677 therefore, a basic unit of input to your �parser�. If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5678 the input to your parser consists of ascii characters, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5679 you may define terminal tokens explicitly as ascii |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5680 characters or as sets of ascii characters. If you have a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5681 lexical scanner, or preprocessor, which produces numeric |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5682 codes, you may define the terminal tokens directly in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5683 terms of these numeric codes. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5684 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5685 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5686 Test File Binary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5687 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5688 "Test file binary" is a �configuration switch� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5689 defaults to off. When it is off, and you select the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5690 �File Trace� option, AnaGram will read your test files |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5691 in "text" mode, discarding carriage return characters. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5692 When "test file binary" is on, AnaGram will read test |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5693 files in "binary" mode, preserving carriage return |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5694 characters. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5695 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5696 If your parser needs to recognize carriage return |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5697 characters explicitly, you should turn "test file |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5698 binary" on. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5699 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5700 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5701 Test File Mask |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5702 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5703 "Test file mask" is a string-valued �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5704 parameter� which AnaGram uses to set up the file dialog |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5705 for the �File Trace� command. It defaults to "*.*". If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5706 there is a conventional file name format for the input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5707 to the �parser� you are developing, you will probably |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5708 want to set "test file mask" in a �configuration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5709 section� in your �syntax file� so it is easier to pick |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5710 out your test files. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5711 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5712 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5713 Test range |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5714 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5715 "Test range" is a �configuration switch� which defaults |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5716 to on. When it is set, i.e., on, AnaGram will configure |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5717 your parser so that it checks input characters to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5718 verify that they are within the range given by the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5719 �character universe� before it indexes the �token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5720 conversion� table. If range testing is not necessary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5721 for your parser, you may turn test range off and get a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5722 slight improvement in the performance of your parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5723 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5724 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5725 Thread Safe Parsers |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5726 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5727 AnaGram 2.01 incorporates several changes designed to make it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5728 easier to write thread safe parsers. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5729 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5730 First, the �parser�s generated by AnaGram 2.01 no longer use static or global |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5731 variables to store temporary data. All nonconstant data have been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5732 moved to the �parser control block�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5733 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5734 Second, two new features which make it substantially |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5735 easier to build thread safe parsers have been added. The �reentrant parser� switch |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5736 makes the entire parser reentrant, by passing the pointer to the parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5737 block as an argument on all function calls. The �extend pcb� statement allows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5738 you to add your own variable declarations to the �parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5739 block� so you can avoid references to global or static variables in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5740 your �reduction procedure�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5741 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5742 Third, new support has been added for C++ classes, including |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5743 the �wrapper� statement and the �PCB_TYPE� macro. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5744 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5745 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5746 token_number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5747 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5748 token_number is a field in a �parser control block� to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5749 which your �error handling� procedures and �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5750 procedure�s may refer. It contains the actual �token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5751 number� of the current input token. If you are supplying |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5752 token numbers directly, it is the result of using the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5753 actual input character to index the �token conversion� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5754 array, ag_tcv. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5755 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5756 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5757 Token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5758 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5759 Tokens are the units with which your parser works. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5760 There are two kinds of tokens: �terminal tokens� and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5761 �nonterminal tokens�. These latter are identified by the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5762 parser as sequences of tokens. The grouping of tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5763 into more complex tokens is governed by the �grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5764 rules�, or �production�s in your grammar. In your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5765 grammar, tokens are denoted by �token name�s, �virtual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5766 productions�, explicit �character representations�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5767 �keyword�s, �immediate action�s, or �expression�s which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5768 yield �character sets�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5769 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5770 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5771 Token Conversion |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5772 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5773 By using �character set� �expression�s, you may in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5774 �syntax file� define a number of input characters as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5775 being syntactically equivalent. When your �parser� gets |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5776 an input character, it uses the character code to index |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5777 a table called �ag_tcv�. The value it extracts from this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5778 table is the �token number� for the input character. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5779 actual character code of the input character becomes the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5780 �token value�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5781 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5782 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5783 Token Declaration |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5784 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5785 A token declaration is simply a �production� with no |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5786 right hand side. Token declarations can be used to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5787 define the �data type�s of tokens. To define the data type |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5788 of a token, simply put the data type in parentheses |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5789 preceding the name of the token. You can use a list of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5790 tokens joined by commas, if you wish. Thus: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5791 (char *) variable name, function name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5792 could be used to specify that the �semantic value�s of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5793 the tokens "variable name" and "function name" are both |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5794 character pointers. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5795 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5796 Of course, token types may be specified as part of any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5797 production the token generates, but sometimes, in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5798 interest of clarity, it is advisable to group all |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5799 declarations together. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5800 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5801 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5802 Token Name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5803 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5804 All �nonterminal tokens� that you define in your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5805 �grammar� by means of explicit �production�s must have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5806 names by which they may be referenced. Token names are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5807 �symbols� which represent the token syntactically in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5808 your grammar specification. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5809 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5810 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5811 Token Names |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5812 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5813 "Token names" is a �configuration switch� that defaults |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5814 to off. If it is set, it causes AnaGram to include in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5815 the �parser file� a static array of character strings, indexed by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5816 token number, which provides ascii representations of token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5817 names. The name of this array is given by "<parser name>_token_names", |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5818 where <parser name> is the name of the parser function as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5819 given by the value of the �parser name� parameter. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5820 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5821 AnaGram also defines a macro, �TOKEN_NAMES�, which evaluates |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5822 to the name of the array. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5823 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5824 The array contains strings for all grammar tokens which have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5825 been explicitly named in the syntax file as well as tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5826 which represent �keyword�s or single character constants. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5827 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5828 The array is useful in creating �syntax error� diagnostics. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5829 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5830 Prior to version 2.01 of AnaGram, the TOKEN_NAMES array contained |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5831 strings only for explicitly named tokens. If this restriction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5832 is required, set the �token names only� switch. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5833 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5834 Token names are also included if the �diagnose errors� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5835 switch is set. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5836 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5837 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5838 TOKEN_NAMES |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5839 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5840 "TOKEN_NAMES" is the name of a macro that AnaGram defines to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5841 provide access to a static array of character strings indexed by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5842 token number, which provides ascii representation of token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5843 names. The array is generated if any of the �token names�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5844 �token names only� or �diagnose errors� switches are ON. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5845 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5846 If �token names only� is set, the array contains non-empty |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5847 strings only for those tokens which are explicitly named |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5848 in the syntax file. Otherwise, the array also contains |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5849 strings for tokens which represent keywords or single |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5850 character constants. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5851 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5852 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5853 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5854 token names only |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5855 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5856 "Token names only" is a �configuration switch� that defaults to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5857 off. If it is set, it will cause AnaGram to include in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5858 parser file a static array containing the names of the tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5859 in your grammar. This array will include only those tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5860 to which you have assigned names explicitly and will not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5861 include character constants or keywords. "Token names only" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5862 takes precedence over �token names�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5863 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5864 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5865 Token Not Used |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5866 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5867 "Token not used, TXXX: <token name> is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5868 message which appears if AnaGram finds an unused �token� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5869 in your �grammar�. Often an unused token is the result |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5870 of an oversight of some kind and indicates a problem in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5871 the grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5872 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5873 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5874 Token Number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5875 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5876 AnaGram assigns a unique number, called the "token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5877 number" to each token in the grammar, no matter whether |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5878 it is a �terminal token� or a �nonterminal token�. Your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5879 parser does all of its analysis of your input stream |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5880 using token numbers as its primary material. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5881 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5882 You may need to know the values of token numbers that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5883 AnaGram has assigned, either so a lexical scanner can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5884 output correct token numbers, or so a �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5885 procedure� can correctly resolve a �semantically |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5886 determined production�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5887 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5888 To help you, AnaGram defines enumeration constants for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5889 each of the named tokens in your grammar. The definition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5890 of these constants is in the �parser header� file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5891 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5892 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5893 Token Representation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5894 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5895 Not all of the �tokens� in your grammar have a �token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5896 name�. Some of the tokens may represent �character sets� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5897 which you spelled out explicitly, �virtual productions�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5898 �immediate action�s, or �keyword�s. In its analysis |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5899 tables, AnaGram tries to provide a meaningful |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5900 representation for tokens whenever it can. Its first |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5901 choice is to use the name, if it has one. Otherwise it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5902 will use the set definition or the definition of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5903 virtual production if one exists. If AnaGram cannot |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5904 otherwise represent your token, it will resort to using |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5905 the token number which it normally represents using the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5906 letter T followed by a three digit, zero-padded token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5907 number. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5908 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5909 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5910 Token Table |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5911 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5912 The Token Table lists all the tokens of your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5913 The first field is the token number. It is followed by a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5914 flag field which is "zl" if the token is a �nonterminal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5915 token� and is �zero length�. If the token is nonterminal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5916 and not zero length, the flag field contains "nt". If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5917 the token is a �terminal token�, the field is blank. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5918 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5919 The next field is blank unless the token has been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5920 declared �sticky� or has had a �precedence� level |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5921 assigned. If the token is sticky, this field will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5922 contain 's'. If a precedence level has been assigned, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5923 this field will contain the letter 'l', 'r', or 'n' to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5924 indicate associativity followed by the precedence |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5925 level. Finally there is the �data type� of the �semantic |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5926 value� of this token and the �token representation�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5927 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5928 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5929 Token Usage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5930 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5931 The Token Usage table may be accessed via the �Auxiliary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5932 Windows� menu from any window that identifies tokens. It |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5933 shows all the rules in the grammar that use the token. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5934 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5935 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5936 Top Margin |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5937 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5938 "Top margin" is an �obsolete configuration parameter�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5939 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5940 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5941 Trace Coverage |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5942 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5943 Trace Coverage is a table which is built whenever you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5944 run �Grammar Trace�, one of its pre-built versions, or a �File |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5945 Trace�. You can access it from the �Browse Menu�. It shows the number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5946 of times each rule in your grammar has been reduced. Unless you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5947 set the �Rule Coverage� �configuration switch�, some �null production�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5948 and some rules that consist of only one element will not be counted |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5949 because of speed optimizations in the parser tables. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5950 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5951 The Trace Coverage tables are reset to zero when you load a new syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5952 file or start AnaGram. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5953 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5954 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5955 Compound Action |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5956 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5957 Traditionally, �LALR-1 parser�s use only four simple |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5958 �parser action�s: shift, reduce, accept and error. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5959 AnaGram parsers use a number of compound actions |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5960 in order to reduce the size of parse tables and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5961 speed up processing. A single compound action |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5962 may replace several simple shift or reduce actions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5963 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5964 The �Traditional Engine� �configuration switch� may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5965 be used to force AnaGram to use only the simple |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5966 actions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5967 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5968 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5969 Traditional Engine |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5970 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5971 "Traditional engine" is a �configuration switch� that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5972 defaults to off. Traditional �LALR-1 parser�s use a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5973 �parsing engine� which has only four actions: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5974 �shift action� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5975 �reduce action� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5976 �accept action� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5977 �error action� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5978 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5979 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5980 AnaGram, in the interest of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5981 faster execution and more compact parse tables, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5982 uses a parsing engine with a number of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5983 short-cut, or �compound action�s. The "traditional engine" switch tells |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5984 AnaGram not to use the short-cut actions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5985 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5986 You would turn this switch on if you wished to use the �Grammar Trace� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5987 or �File Trace� to see how the standard four parser actions work for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5988 a particular combination of grammar and input. Note that to see the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5989 effects of single parser actions, you must use the �Single Step� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5990 button. Remember that in the Grammar Trace, when you single step and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5991 the token you have selected causes a reduce action, it will appear |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5992 on the �lookahead line� of the �parser stack pane� and will be preselected |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5993 in the �allowable input pane� until it is finally shifted in to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5994 the parser stack. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5995 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5996 Normally, you should leave the "traditional engine" switch off, Then |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5997 AnaGram will, whenever possible, compress several parsing actions into |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5998 one compound action in order to speed execution of the parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
5999 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6000 Unfortunately use of the term "traditional" has sometimes created the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6001 impression that there is a conservative aspect to the operation of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6002 traditional engine parsers. This is not the case. They have the same |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6003 effect, but are slower and have much larger tables. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6004 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6005 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6006 Type Redefinition |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6007 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6008 "Type Redefinition of TXXX: <token name> is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6009 message which appears when AnaGram finds a conflicting |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6010 �data type� definition for a �token� in your �grammar�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6011 The new definition will override the previous one. If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6012 you intend to use different type definitions, you should |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6013 use extreme caution and check the generated code to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6014 verify that your �reduction procedure�s are getting the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6015 values you intended. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6016 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6017 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6018 Undefined Symbol |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6019 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6020 "Undefined symbol: <name>" is a �warning� message which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6021 appears when AnaGram encounters an undefined �symbol� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6022 while evaluating a �character set� expression. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6023 following warning in the �Warnings� window identifies |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6024 the particular �token� AnaGram was trying to evaluate. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6025 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6026 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6027 Undefined Token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6028 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6029 "Undefined token TXXX: <name>" is a �warning� message |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6030 which appears when the indicated �token� has been used |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6031 in the �grammar�, but there is no definition of it as a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6032 �terminal token� nor does any �production� define it as |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6033 a �nonterminal token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6034 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6035 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6036 Unexpected |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6037 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6038 "Unexpected <element 1> in <element 2>" is a �warning� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6039 message which you may get when AnaGram analyzes your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6040 grammar. It appears when AnaGram unexpectedly encounters an instance of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6041 syntactic element 1 at the specified location in an instance of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6042 syntactic element 2. AnaGram cannot reliably continue parsing its |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6043 input. Therefore, it limits further analysis to scanning for syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6044 errors. If this error is not the result of a prior error, you should |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6045 correct your �syntax file�. Remember that this error could result from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6046 something missing just as well as from something extraneous. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6047 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6048 If element 1 is �eof�, it often means that you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6049 an unbalanced brace or comment delimiter in the code |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6050 following the indicated location. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6051 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6052 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6053 Union |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6054 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6055 The union of two sets is the set of all elements that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6056 are to be found in one or another of the two sets. In an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6057 AnaGram syntax file the union of two �character sets� A |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6058 and B is represented using the plus sign, as in A + B. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6059 The union operator has the same precedence as the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6060 �difference� operator: lower than that of �intersection� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6061 and �complement�. The union operator is �left |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6062 associative�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6063 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6064 Watch out! In an AnaGram syntax file 65 + 97 represents |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6065 the character set which consists of the lower case 'a' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6066 and upper case 'A'. It does not represent 162, the sum |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6067 of 65 and 97. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6068 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6069 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6070 Video mode |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6071 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6072 "Video mode" is an �obsolete configuration parameter�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6073 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6074 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6075 Virtual Production |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6076 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6077 Virtual productions are a special short hand |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6078 representation of �grammar rules� which can be used to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6079 indicate a choice of inputs. They are an important |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6080 convenience, especially useful when you are first |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6081 building a grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6082 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6083 Here are some examples of virtual productions: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6084 name? // optional name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6085 name?... // 0 or more instances of name |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6086 {name | number} // exactly one name or number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6087 {name | number}... // one or more instances of name or number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6088 [name | number] // optional choice of name or number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6089 [name | number]... // zero or more instances of name or number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6090 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6091 AnaGram rewrites virtual productions, so that when you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6092 look at the syntax tables in AnaGram, there will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6093 actual �production�s replacing the virtual productions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6094 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6095 A virtual production appears as one of the rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6096 elements in a grammar rule, i.e. as one of the members |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6097 of the list on the right side of a production. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6098 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6099 The simplest virtual production is the "optional" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6100 token. If x is an arbitrary token, x? can be used to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6101 indicate an optional x. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6102 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6103 Related virtual productions are x... and x?... where |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6104 the three dots indicate repetition. x... represents an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6105 arbitrary number of occurrences of x, but at least one. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6106 x?... represents zero or more occurrences of x. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6107 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6108 The remaining virtual productions use curly or square |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6109 brackets to enclose a sequence of rules. The brackets |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6110 may be followed variously by nothing, a string of three |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6111 dots, or a slash, to indicate the choices to be made |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6112 from the rules. Note that rules may be used, not merely |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6113 tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6114 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6115 If r1 through rn are a set of �grammar rules�, then |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6116 {r1 | r2 | ... | rn} |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6117 is a virtual production that allows a choice of exactly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6118 one of the rules. Similarly, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6119 {r1 | r2 | ... | rn}... |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6120 is a virtual production that allows a choice of one or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6121 more of the rules. And, finally, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6122 {r1 | r2 | ... | rn}/... |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6123 is a virtual production that allows a choice of one or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6124 more of the rules subject to the side condition that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6125 rules must alternate, that is, that no rule can follow |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6126 itself immediately without the interposition of some |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6127 other rule. This is a case that is not particularly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6128 easy to write by hand, but is quite useful in a number |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6129 of contexts. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6130 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6131 If the above virtual productions are written with [] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6132 instead of {}, they all become optional. [] is an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6133 optional choice, []... is zero or more choices, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6134 []/... is zero or more alternating choices. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6135 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6136 Null productions are not permitted in virtual |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6137 productions in those cases where they would cause an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6138 intrinsic ambiguity. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6139 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6140 You may use a �definition� statement to assign a name to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6141 a virtual production. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6142 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6143 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6144 Void token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6145 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6146 "Void token, <token name>, used as parameter" is a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6147 �warning� message which appears if AnaGram encounters a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6148 �data type� definition declaring a �token� to have type |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6149 void when the token has previously been used in a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6150 �parameter assignment� for a �reduction procedure�. Your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6151 C or C++ compiler will complain when it tries to compile |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6152 the call to the reduction procedure. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6153 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6154 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6155 vs |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6156 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6157 vs is a field in a �parser control block� to which your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6158 �error handling� procedures and �reduction procedure�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6159 may refer. It is the �parser value stack� for your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6160 parser. The �semantic values� of the �tokens� identified |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6161 by the parser are stored in the value stack. The value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6162 stack, like the other �parser stacks�, is indexed by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6163 �PCB�.�ssx�. When you are executing a reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6164 procedure, PCB.vs[PCB.ssx] contains the semantic value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6165 of the first token in the grammar rule you are reducing, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6166 PCB.vs[PCB.ssx+1] contains the second, and so forth. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6167 return value from your reduction procedure will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6168 stored in turn in PCB.vs[PCB.ssx]. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6169 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6170 vs is defined to be of type $_vt, where "$" represents |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6171 the name of your parser. AnaGram defines $_vt to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6172 be a union of fields of sizes corresponding to all the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6173 different data types declared in your syntax for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6174 semantic values of your tokens. In order to avoid |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6175 restrictions on the use of C++ classes, the fields are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6176 defined as character arrays. On some processors which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6177 have byte alignment restrictions for multibyte data, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6178 you might encounter a bus error. To correct this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6179 problem, set the �parser stack alignment� parameter to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6180 an appropriate data type. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6181 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6182 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6183 Warning |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6184 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6185 If while analyzing your syntax file, AnaGram finds |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6186 something suspicious, it is likely to issue a warning. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6187 The Warnings window will pop up automatically when the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6188 analysis has been completed. If the warning is for a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6189 �syntax error� in your input file, you will have to fix |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6190 it, because AnaGram cannot successfully interpret it. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6191 Otherwise, AnaGram will be able to create a �parser� for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6192 you, if you wish, no matter how serious the warnings may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6193 be. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6194 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6195 You can bring up the Help topic associated with a highlighted warning |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6196 by pressing F1 or by clicking with a �Help Cursor�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6197 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6198 If you have syntax errors, AnaGram will synchronize the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6199 cursor in the �syntax file� window with the cursor in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6200 Warnings window so that whenever the Warnings window is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6201 active, the cursor bar in the syntax file window will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6202 identify the location of the error. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6203 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6204 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6205 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6206 What's New |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6207 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6208 Changes in AnaGram 2.40 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6209 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6210 Most of the changes in AnaGram 2.40 are under the hood - cleanup of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6211 source files, reorganization of the source tree, revision of build and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6212 test procedures, and so forth, in preparation for the open source |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6213 release. All of this will, with luck, be invisible to the end user. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6214 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6215 Open Source |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6216 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6217 AnaGram is now �open source�. AnaGram itself |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6218 uses the 4-clause BSD �license�; the �parsing engine�, and thus the output |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6219 files, are licensed with the less restrictive zlib �license�. Source |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6220 distributions are available from http://www.parsifalsoft.com. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6221 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6222 The manual has been re-typeset using LaTeX instead of WordPerfect. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6223 The typographic consistency and formatting has been considerably |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6224 improved; unfortunately, the pagination is now completely different, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6225 so page numbers are not portable to the new version. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6226 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6227 All the logic dealing with registration, trial copies, serial numbers, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6228 and so forth has been removed. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6229 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6230 Unix Support |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6231 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6232 The Unix build of the �command line version� of AnaGram (agcl) is now |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6233 supported and available to the public. There is at present no GUI for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6234 the Unix version. The long-term goal is to migrate the AnaGram GUI |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6235 away from the closed (and orphaned) IBM Visual Age class library to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6236 something else, probably GTK, so as to support both Windows and Unix. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6237 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6238 Improved Functionality |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6239 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6240 Examples. The examples have been adjusted to the current dialect of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6241 C++ and are now compilable again. The legacy "classlib" code some |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6242 still depend on is being phased out. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6243 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6244 Increased Convenience |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6245 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6246 File names. File names in the AnaGram distribution and source |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6247 tree are no longer limited to 8+3 characters, and quite a few now have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6248 less cryptic names. Additionally, all HTML files are now named ".html", |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6249 not ".htm". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6250 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6251 Installed files. The AnaGram.cgb and AnaGram.hlp files found in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6252 older releases of AnaGram no longer exist; their contents are compiled |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6253 into the AnaGram executables instead. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6254 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6255 Bug Fixes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6256 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6257 Engine compiler error. The �error_message� field of the PCB has |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6258 been changed to const char * so current C++ compilers will accept the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6259 code generated when �diagnose errors� is turned off. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6260 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6261 Multiple output header files. Including more than one AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6262 output header file at once used to cause some compilers to issue a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6263 warning, because an #ifndef directive was checking the wrong |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6264 symbol. This has been corrected. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6265 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6266 Wrappers and error tokens. AnaGram 2.01 generated uncompilable |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6267 code if you tried to use the �wrapper� feature and error token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6268 resynchronization at the same time. This has been corrected. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6269 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6270 More than 256 keywords. Build 8 of AnaGram 2.01 fixed certain |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6271 problems with large keyword tables, but in the process introduced |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6272 another, which is now fixed. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6273 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6274 For changes in the previous versions of AnaGram, see �What's New in AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6275 2.01� and �What's New in AnaGram 2.0�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6276 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6277 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6278 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6279 What's New in AnaGram 2.01 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6280 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6281 Changes in AnaGram 2.01 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6282 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6283 Improved Functionality |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6284 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6285 Improved support for building �thread safe parsers�. All |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6286 nonconstant parser data previously declared as static variables has been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6287 moved to the �parser control block�. When the �reentrant parser� switch |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6288 is set, all references to the parser control block are passed to functions |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6289 via calling sequences. The �extend pcb� switch provides a mechanism to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6290 add user-defined variables to the parser control block. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6291 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6292 Improved support for C++ parsers. The �wrapper� statement |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6293 provides C++ wrapper classes for objects to be stored on the �parser value stack�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6294 The �PCB_TYPE� macro allows you to derive a C++ class from the parser control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6295 block and to access its members from your �reduction procedures�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6296 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6297 Support for the �ISO Latin 1� character set. When using |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6298 the �case sensitive� switch, case conversion is performed for all ISO-Latin-1 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6299 characters, not just those in the ASCII range. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6300 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6301 Improved support for error diagnostics. It is now possible for users |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6302 to provide their own text for the error messages created by the �diagnose errors� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6303 switch. In addition, the �token names� table option now includes ascii representation |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6304 of individual characters and keywords instead of only named tokens. The �token names |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6305 only� switch can be used for compatibility with previous versions of AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6306 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6307 More precise determination of error context. The tables used by the �error frame� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6308 option to provide the context of a syntax error have been reworked and now provide |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6309 a substantially more precise localization of the error. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6310 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6311 Improved error diagnostics in AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6312 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6313 �Missing reduction procedure� diagnostic. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6314 In addition to warning that there is a �parameter assignment� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6315 without a �reduction procedure�, this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6316 diagnostic is now provided if the �default reduction value� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6317 does not have the same �data type� as the �reduction token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6318 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6319 �Command line version�. Diagnostics have been reformatted so |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6320 they can be recognized by the Microsoft Visual C++ IDE. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6321 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6322 Refined �keyword anomaly� diagnostics. There should |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6323 now be fewer false alarms. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6324 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6325 Increased Convenience |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6326 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6327 �File Trace�. If your grammar uses �semantically determined productions�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6328 the File Trace feature will now remember the choices you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6329 made for �reduction token�s, so that you do not have to make |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6330 the same choices over and over again as you work with an example. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6331 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6332 File Paths. The file paths in the #line directives created by the �line numbers� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6333 switch now use forward slashes instead of backslashes. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6334 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6335 Changed Defaults |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6336 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6337 �Parser stack alignment�. Now defaults to long instead of int. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6338 �Parser stack size�. Now defaults to 128 instead of 32. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6339 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6340 Bug Fixes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6341 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6342 Interaction between context tracking and error token. In previous |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6343 versions of AnaGram, if the first token in a rule was the �error token�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6344 the value of �CONTEXT� was the value that corresponded to the location |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6345 of the error. CONTEXT now correctly shows the context at which the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6346 aborted rule began. For instance, in the following example, if a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6347 syntax error is encountered while parsing the expression, the error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6348 rule will skip over remaining characters to the terminating semicolon. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6349 When invoked from handleError(), the CONTEXT macro will return the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6350 context as it was at the beginning of the expression. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6351 expression statement |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6352 -> expression, ';' |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6353 -> error, ~(eof + ';')?..., ';' =handleError(); |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6354 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6355 �Distinguish lexemes�. Several minor bugs in the implementation of distinguish lexemes have been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6356 corrected. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6357 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6358 Set partition logic. Corrected problems in the interaction between the set �partition� logic |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6359 and the implementation of the �disregard� statement. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6360 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6361 Table size. Fixed a data sizing problem which occurred when one particular parse table |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6362 had precisely 256 entries. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6363 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6364 Keyword recognition. Fixed a problem that could cause difficulties with �keyword� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6365 recognition when the �case sensitive� switch was turned off. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6366 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6367 Default conflict resolution. With unresolved �shift-reduce conflict�s, the shift case was |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6368 not always being selected. This problem has been corrected. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6369 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6370 Lockup. It was possible to write an erroneous grammar that would cause |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6371 AnaGram to lock up. This problem has been corrected. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6372 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6373 Potential bus error. The error diagnostic funtion created by the �diagnose errors� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6374 switch, could, under some circumstances, access an uninitialized value |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6375 on the �parser value stack�. This problem has been corrected. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6376 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6377 Internal errors. Fixed a number of minor bugs which could cause �internal error�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6378 while running �File Trace�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6379 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6380 For changes in the previous version of AnaGram, see �What's New in AnaGram 2.0�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6381 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6382 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6383 What's New in AnaGram 2.0 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6384 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6385 AnaGram's user interface has been completely revamped to make it more |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6386 convenient and easier to use. However, the same tried and true AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6387 algorithms are still in place to build your parsers. The rules for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6388 syntax files are also unchanged. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6389 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6390 The �File Trace� and �Grammar Trace� facilities have each had their |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6391 windows combined into a single unit, and a �Rule Stack� synched with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6392 these windows and with your syntax file window has been added. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6393 Rule Stack is particularly convenient for relating the progress of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6394 parse to the �grammar rules� in your �syntax file�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6395 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6396 A �text entry� field has also been added to the Grammar Trace. This |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6397 means you can provide character input to your parser in much the same |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6398 way you can with a �test file� in File Trace, but with instant control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6399 over the input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6400 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6401 Some further controls have been added to both File and Grammar Traces. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6402 In particular there is a Reset button to reset the trace to its initial |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6403 state. This is particularly useful for �Conflict Trace�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6404 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6405 AnaGram now has a small �Control Panel� (default position is at the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6406 upper right of the screen) from which you can conveniently control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6407 operation. A menu bar provides access to the various commands and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6408 tables. There are toolbar buttons for Analyze Grammar, Build Parser, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6409 File Trace, and so on. The panel also has a data entry field for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6410 entering search keys. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6411 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6412 You can set both colors and fonts in AnaGram windows to suit your own |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6413 preferences. We suggest you check Help for �Colors� or �Fonts� before |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6414 making changes to make sure that all information will still be properly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6415 displayed. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6416 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6417 AnaGram's �Help� has been updated to provide hypertext-type links. But |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6418 you can still keep multiple Help windows on view at once. A popup menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6419 shows all the links in a window. New topics have been added. Also, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6420 further documentation topics are provided in HTML format in the html |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6421 subdirectory. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6422 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6423 A �Help Cursor� on the Control Panel toolbar can be used to get help for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6424 most AnaGram windows, buttons and menu items. F1 can also be used. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6425 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6426 On the �Action Menu� you will find a list of your most recently used |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6427 syntax files. Just click on the file of your choice to have AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6428 analyze it (or build it if �Autobuild� is on). |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6429 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6430 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6431 White Space |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6432 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6433 In many grammars it is desirable to pass over blanks, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6434 tabs, and similar characters, as well as comments, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6435 collectively termed "white space", as though they were |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6436 not there. The "�disregard�" statement in AnaGram may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6437 be optionally used to accomplish this. The "�lexeme�" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6438 statement may be used to exercise fine control over the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6439 scope of the disregard statement. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6440 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6441 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6442 Wrapper |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6443 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6444 The wrapper �attribute statement� provides correct handling of C++ |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6445 objects returned by �reduction procedure�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6446 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6447 If you specify a wrapper for a C++ object, then, when a reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6448 procedure returns an instance of the object, a copy of the object will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6449 be constructed on the �parser value stack� and the destructor will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6450 called when the object is removed from the stack. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6451 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6452 Without a wrapper, objects are stored on the value stack simply |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6453 by coercing the stack pointer to the appropriate type. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6454 There is no constructor call when the object is stored nor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6455 a destructor call when it is removed from the stack. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6456 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6457 Classes which use reference counts or otherwise overload the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6458 assignment operator should always have wrappers in order to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6459 function correctly. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6460 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6461 Wrapper statements, like other �attribute statements�, must appear in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6462 configuration sections. The syntax is simply |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6463 wrapper { <comma delimited list of data types> } |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6464 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6465 For example: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6466 [ |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6467 wrapper {CString, CFont} |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6468 ] |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6469 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6470 You cannot specify a wrapper for the �default token type�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6471 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6472 If your parser exits with an error condition, there may be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6473 objects remaining on the stack. The �DELETE_WRAPPERS� macro |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6474 may be used to delete these objects. If you have enabled |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6475 �auto resynch�, DELETE_WRAPPERS will be invoked automatically. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6476 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6477 The �AG_PLACEMENT_DELETE_REQUIRED� macro is used to control |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6478 definition of a "placement delete" operator in the wrapper |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6479 class AnaGram defines. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6480 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6481 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6482 Zero Length |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6483 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6484 A zero length �token� is a �reduction token� which can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6485 be matched by a void, i.e. by nothing at all. It |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6486 represents an optional item, or a sequence of optional |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6487 items, in the input. Since the matching process can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6488 involve several levels of reductions, it is most precise |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6489 to use the following recursive definition: A zero length |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6490 token is one which either has at least one �null |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6491 production� or has at least one grammar rule defining it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6492 such that all the tokens in the rule are zero length |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6493 tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6494 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6495 Care should be taken when using �zero length� tokens in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6496 �recursive rule�s. If all the tokens in the rule other than |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6497 the recursive token itself are zero length tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6498 the rule will generate an infinite loop in the generated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6499 parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6500 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6501 The �Token Table� identifies zero length tokens because |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6502 the use of such tokens sometimes inadvertently causes |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6503 �conflict�s. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6504 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6505 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6506 Control Panel |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6507 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6508 The AnaGram Control Panel appears at the upper right of your monitor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6509 when you start AnaGram. It has a menu bar, command buttons, a button |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6510 which enables a �help cursor�, and a �status indicator�. At the lower |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6511 left you will see a data entry field for entering �search� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6512 keys, with neighboring search forward and search backward buttons. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6513 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6514 Notice that the �Options Menu� has a "Stay On Top" entry which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6515 allows you to specify whether the Control Panel stays on top of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6516 other AnaGram windows. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6517 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6518 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6519 Status Indicator |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6520 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6521 The status indicator at the right of the AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6522 Control Panel shows the status of the �current grammar�: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6523 Ready |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6524 Loaded |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6525 Error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6526 Parsed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6527 Analyzed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6528 Built |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6529 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6530 "Ready" appears only when no grammar has been selected. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6531 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6532 "Loaded" and "Parsed" are normally transitory. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6533 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6534 "Error" means at least one syntax error has been detected |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6535 in your grammar and AnaGram cannot continue. Check the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6536 Warnings window to determine the nature of the problem. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6537 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6538 "Analyzed" means that a �grammar analysis� has been |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6539 completed, but no �output files� have been written. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6540 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6541 "Built" means that an analysis has been completed and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6542 output files have been written. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6543 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6544 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6545 Help Cursor |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6546 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6547 The Help Cursor is accessed via the button with the question mark on |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6548 AnaGram's �Control Panel�. It is convenient for getting help on |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6549 �Warning�s, browse tables, menu items and so on. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6550 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6551 If you click on the button you enable the Help Cursor, which you can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6552 then drag with the mouse. A further mouse click will provide help |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6553 for the item underneath the cursor. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6554 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6555 Note further that AnaGram also has F1 help which you may find |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6556 simpler and faster than the Help Cursor. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6557 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6558 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6559 Search |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6560 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6561 AnaGram has a simple search facility to let you search for text strings |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6562 in AnaGram windows. A data entry field on the �Control Panel� is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6563 provided for you to enter text. Left-clicking on the neighboring |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6564 buttons lets you search either forward or backward for a line in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6565 active window which contains at least one instance of the text. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6566 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6567 Note that the search begins at the next line after the highlighted line |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6568 for forward search; at the line preceding the highlighted line for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6569 backward search. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6570 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6571 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6572 Search Key |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6573 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6574 To find a text string in an AnaGram window, enter the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6575 string in the Search Key field in the �Control Panel� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6576 and press Enter. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6577 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6578 To find another instance of the string click on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6579 �Find Next� button or press F3. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6580 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6581 To find a previous instance of the string click on |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6582 the �Find Previous� button or press F4. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6583 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6584 In windows that have a cursor bar, a forward search |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6585 begins on the line following the cursor and a backward |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6586 search begins on the line preceding the cursor. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6587 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6588 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6589 Find Next |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6590 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6591 The Find Next key, on the �Control Panel� immediately |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6592 to the right of the �Search Key� field, locates |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6593 the next instance of the search key in the most recently |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6594 active AnaGram window. F3 is the keyboard equivalent. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6595 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6596 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6597 Find Previous |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6598 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6599 The Find Previous key, on the �Control Panel� immediately |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6600 to the right of the �Find Next� key, searches |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6601 backwards for the search key in the most recently |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6602 active AnaGram window. F4 is the keyboard equivalent. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6603 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6604 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6605 Fonts, Set Fonts |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6606 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6607 The Set Fonts dialog allows you to use the fonts of your choice in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6608 AnaGram windows. You should make sure that the �marked token�s font is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6609 very distinctive so that marked tokens will show up clearly even if |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6610 they are only 1 or 2 characters long. Sometimes it is helpful to use an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6611 underlined font for marked tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6612 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6613 A Default button at the bottom of the dialog lets you revert to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6614 AnaGram's original fonts if you wish. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6615 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6616 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6617 Colors, Set Colors |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6618 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6619 The Set Colors dialog allows you change the colors of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6620 AnaGram windows. Notice that in the �File Trace� the �test file pane� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6621 requires three different sets of text and background colors. You |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6622 should make sure that the backgrounds, at least, can be easily |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6623 distinguished from each other so the trace information can be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6624 properly displayed. You also want to take care that an active pane in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6625 a File Trace or Grammar Trace can be distinguished from inactive |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6626 panes. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6627 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6628 The Default button at the bottom of the dialog lets you revert to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6629 AnaGram's original colors if you wish. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6630 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6631 Color changes pertain only to the client areas of AnaGram windows. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6632 remaining parts of your windows will have the customary colors you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6633 chosen for your system. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6634 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6635 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6636 Marked Token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6637 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6638 Some tables and trace panes display each rule with one token marked to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6639 show how far parsing has progressed in the rule. The marked token is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6640 the next input expected in the input stream. It is shown in a different |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6641 font to distinguish it from other tokens in the rule. If no token is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6642 marked, the rule is a �completed rule�, i.e. it has been completely |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6643 matched and will be reduced by the next input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6644 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6645 You can set the font for marked tokens by choosing Fonts from the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6646 �Options Menu�. You should make sure that the font is very distinctive so |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6647 that marked tokens will show up clearly even if they are only 1 or 2 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6648 characters long. Sometimes it is helpful to use an underlined font for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6649 marked tokens. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6650 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6651 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6652 Synch Parse |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6653 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6654 The Synch Parse button replaces the �Single Step� button on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6655 toolbar of the �File Trace window� when, for some reason, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6656 location of the blinking cursor in the �test file pane� differs from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6657 the current parse position. This can occur when you single click in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6658 the test file pane or when the parse cannot track the cursor because |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6659 of a �syntax error� or a �semantically determined production�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6660 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6661 Click the synch parse button to resynch the parse with the cursor. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6662 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6663 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6664 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6665 Single Step |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6666 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6667 The Single Step button is one of the control buttons for the �File |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6668 Trace� and �Grammar Trace�. It advances the parse one �parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6669 action� at a time. In the File Trace, it is replaced with the "�Synch |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6670 Parse�" button whenever the blinking cursor loses synch with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6671 the current parse location. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6672 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6673 In the Grammar Trace, the Single Step button takes its input from the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6674 Allowable Input pane, the Reduction Choices pane, or the �text entry� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6675 field, depending on which is active. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6676 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6677 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6678 Proceed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6679 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6680 The Proceed button is one of the control buttons for the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6681 �Grammar Trace�. If the �Reduction Choices pane� or the �Allowable |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6682 Input pane� is active, Proceed parses the highlighted token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6683 until it is shifted in to the �parser stack�. If the �text entry� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6684 field is active, Proceed parses all text in the field. If a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6685 �syntax error� is encountered, the parse stops and all �reduce |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6686 action�s are undone. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6687 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6688 Note that selecting a token in Allowable Input can cause a syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6689 error under certain circumstances. This can happen only if the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6690 following conditions are all true: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6691 the indicated operation is a �reduction�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6692 the reduction token for the rule being reduced has been used in several |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6693 different contexts in the grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6694 and the specified token may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6695 follow it in some contexts and not in others. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6696 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6697 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6698 Reduction Choices Pane |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6699 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6700 The �File Trace� and �Grammar Trace� display a Reduction Choices |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6701 pane when they need to reduce a �semantically determined production�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6702 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6703 The rule to be reduced is highlighted in the �rule stack pane�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6704 If the �syntax file� window is visible, it shows the rule in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6705 context in your grammar. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6706 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6707 The Reduction Choices pane lists all possible �reduction token�s for |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6708 the specified rule. The first reduction token that is admissible in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6709 the current context is highlighted and it appears |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6710 as the �lookahead token� in the �parser stack pane�. The text that |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6711 comprises the entire rule is highlighted in the �test file pane�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6712 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6713 Select the desired reduction token before continuing with the parse. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6714 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6715 If you select a token and it does not appear as the lookahead token, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6716 it is not syntactically correct in the current context. If you try |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6717 to proceed with the parse, you will get a �selection error�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6718 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6719 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6720 Selection Error |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6721 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6722 The �Parse Status� field indicates a "selection error" if you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6723 choose a �reduction token� from the �Reduction Choices pane� of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6724 a �File Trace� or �Grammar Trace� and the selected token is not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6725 syntactically correct in the current context. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6726 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6727 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6728 Parser Stack Pane |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6729 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6730 The Parser Stack pane, the upper left pane of the �File Trace� and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6731 �Grammar Trace� windows, displays the �parser stack� for the current |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6732 trace. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6733 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6734 Each line corresponds to one level in the parser state stack. It shows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6735 the stack index, the �parser state� for that level, and the �token� which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6736 was seen at that state. The last line of the stack, the �lookahead |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6737 line�, corresponds to the current state of the parser. Since no input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6738 has yet been processed for this state, the token, if any, which |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6739 appears at this level is a �lookahead token�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6740 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6741 If you move the cursor in the Parser Stack pane of a File Trace, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6742 the text that makes up the selected token will be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6743 highlighted in the �Test File pane�. You can back the parse up to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6744 any desired stack level by double clicking at the beginning of the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6745 token text in the Test File pane. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6746 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6747 Similarly, if you move the cursor bar in the Parser Stack pane of a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6748 Grammar Trace, the �Allowable Input pane� will change to display the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6749 allowable tokens in the selected state. The previously |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6750 selected token will be highlighted. Then, double click on any token in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6751 the Allowable Input pane to back the parse up and choose a token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6752 a second time. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6753 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6754 The �Rule Stack pane� of the File or Grammar Trace is also synched |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6755 to the Parser Stack pane. If the �syntax file� window is visible, it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6756 will be synched to show the rule currently selected in the rule |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6757 stack pane. Note that rules that have been automatically generated |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6758 by the expansion of �virtual productions� cannot be synched, so the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6759 top line of the syntax file will be highlighted instead. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6760 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6761 In the Grammar Trace, the last line of the Parser Stack may or may not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6762 display a �lookahead token�, depending on the last �parser action� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6763 performed. If input was taken from Allowable Input and the last |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6764 action was a simple �reduce action�, the last input token selected |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6765 will be displayed as the lookahead input. But if the last action |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6766 performed shifted the token in, the lookahead field will be empty. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6767 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6768 If you right-click on a highlighted line in the Parser Stack pane, you will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6769 get a pop-up menu to give you more information. In particular you can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6770 get an �Auxiliary Trace� starting at the current point in your File or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6771 Grammar Trace, so you can explore various possibilities without losing |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6772 your position in the old trace. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6773 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6774 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6775 Exit |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6776 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6777 Select this entry from the �Action Menu� to terminate AnaGram. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6778 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6779 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6780 Allowable Input, Allowable Input Pane |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6781 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6782 The upper right pane of the �Grammar Trace� window lists the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6783 allowable input tokens for the current state of the �grammar�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6784 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6785 The tokens in the Allowable Input pane are listed in two groups: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6786 first, the �terminal tokens� allowable in this state, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6787 second, the �nonterminal tokens�. Between these two groups of tokens |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6788 is inserted a line which is either an option for a �default reduction�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6789 or declares that there is no default action. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6790 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6791 Double click, press Enter, or click the �Proceed� button to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6792 parse the highlighted token. When all parse actions triggered |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6793 by the highlighted token have been completed, all panes of the trace |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6794 will be redrawn to show the new state of the parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6795 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6796 Note that selecting a token in Allowable Input can cause a syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6797 error under certain circumstances. This can happen only if the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6798 following conditions are all true: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6799 the indicated operation is a �reduction�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6800 the reduction token for the rule being reduced has been used in several |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6801 different contexts in the grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6802 and the specified token may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6803 follow it in some contexts and not in others. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6804 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6805 If you wish to see the results of a single parser action, click |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6806 on the �single step� button. The parser will perform a single |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6807 parser action. If the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6808 token you selected was not shifted in, it will now be displayed |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6809 as the �lookahead token� on the last line, the �lookahead line� in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6810 the �Parser Stack pane�, and will be preselected in the Allowable |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6811 Input pane. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6812 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6813 Because AnaGram, by default, uses a number of compound |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6814 parser actions, this situation does not arise very often unless you |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6815 have set the �traditional engine� switch or reset the �default |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6816 reductions� switch. Usually you will want to select the same token to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6817 proceed, but it is not necessary. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6818 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6819 The Allowable Input pane also displays |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6820 the �parser action� associated with a specific token. If it is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6821 not a �compound action�, the action and its result are also shown. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6822 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6823 The �parser action� field for a token may be interpreted as follows: If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6824 this token would cause a shift to a new state, the action field is ">>" |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6825 followed by the new state number. If the token would cause a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6826 �reduction�, the action field is "<<" followed by a �rule number� to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6827 show the rule reduced. If the parser action is a compound action, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6828 action field is blank. If the token would cause the grammar to be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6829 accepted, the action field is "Accept". |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6830 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6831 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6832 The �text entry� field at the bottom of the Grammar Trace can be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6833 used as a convenient alternative to the Allowable Input pane. It |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6834 accepts characters rather than tokens. Most non-printing characters |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6835 such as newline are only available from Allowable Input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6836 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6837 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6838 Copy |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6839 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6840 The Copy command on the �Windows Menu� copies the currently active |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6841 table or Help topic to the clipboard. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6842 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6843 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6844 Statistical Summary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6845 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6846 While your grammar is being analyzed, a Statistical Summary window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6847 pops up to show you the progress of the analysis. Unless you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6848 turned off �Show Statistics� on the �Options Menu�, this window will remain |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6849 on-screen for your reference. Among other things, it shows you the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6850 number of rules and states in your grammar, and the number of conflicts |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6851 and warnings, if any. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6852 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6853 Note that if your grammar is small and you have Show Statistics turned |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6854 off, the appearance of this window on your monitor may be exceedingly |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6855 brief - you may just see a flash. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6856 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6857 If the window is turned off or you have closed it, you can get it from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6858 the �Browse Menu�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6859 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6860 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6861 Stay On Top |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6862 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6863 The Stay On Top entry in the �Options Menu� allows you to specify whether |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6864 the �Control Panel� stays on top of other AnaGram windows. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6865 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6866 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6867 Show Syntax |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6868 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6869 If this entry in the �Options Menu� is checked, AnaGram will display the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6870 �syntax file� when it has analyzed your �grammar�. If this entry is not checked |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6871 or you have closed the syntax file window, you can select the window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6872 from the �Browse Menu�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6873 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6874 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6875 Show Statistics |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6876 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6877 If this entry in the �Options Menu� is checked, AnaGram will leave the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6878 �Statistical Summary� on the screen after it has analyzed your �grammar�. If |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6879 this entry is not checked or you have closed the Statistical Summary |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6880 window, you can select the window from the �Browse Menu�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6881 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6882 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6883 About AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6884 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6885 Select this entry from the �Help Menu� to find out the version and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6886 serial numbers of your copy of AnaGram, and how to contact Parsifal |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6887 Software. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6888 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6889 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6890 Help Topics |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6891 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6892 Select Help Topics from the �Help Menu� to get a complete list of AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6893 Help Topics titles. You can bring up the window for a highlighted topic |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6894 by double-clicking with the left mouse button, pressing F1, or using |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6895 the �Help Cursor�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6896 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6897 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6898 Cascade Windows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6899 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6900 Select this entry from the �Windows Menu� to cascade your open windows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6901 starting at top left of the screen. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6902 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6903 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6904 Close Windows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6905 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6906 Select this entry from the �Windows Menu� to close all open windows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6907 except the �Control Panel�. You may also close the active window |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6908 by pressing the Escape key. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6909 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6910 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6911 Hide Windows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6912 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6913 Select this entry from the �Windows Menu� to hide all open windows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6914 except the �Control Panel�. Restore them to the screen with �Restore |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6915 Windows� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6916 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6917 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6918 Restore Windows |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6919 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6920 Use this command on the �Windows Menu� to restore to the screen |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6921 any windows you have previously hidden with �Hide Windows�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6922 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6923 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6924 Token Input, Preprocessor, Lexical Scanner |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6925 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6926 AnaGram makes it unnecessary, in most cases, to have a separate |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6927 preprocessor to provide the �tokens� which are fed to your parser. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6928 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6929 However in some cases you may want to use a preprocessor, or lexical |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6930 scanner, to provide input to your parser. The preprocessor may |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6931 or may not be written in AnaGram. If it sends the parser token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6932 numbers, as opposed to character codes, this is referred to as token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6933 input, as opposed to character input. Please refer to the AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6934 User's Guide for information on identifying the tokens to the parser |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6935 and providing their semantic values, if any. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6936 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6937 Since a �File Trace� is based on character codes, it will be greyed out |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6938 on the �Action Menu� if you have token input. For a �Grammar Trace�, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6939 entering characters in the �text entry� field is not appropriate and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6940 will simply cause a syntax error. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6941 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6942 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6943 Lookahead Line |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6944 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6945 The last line of the �Parser Stack pane�, the "lookahead" line, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6946 will sometimes show a �lookahead |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6947 token�, and sometimes not. In a �File Trace�, you will always see a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6948 lookahead token because it is available from the �test file�. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6949 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6950 In a �Grammar Trace� you will usually see a lookahead token only when |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6951 you have used the �Single Step� button or if there is available |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6952 input in the �text entry� field. In the latter case the token |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6953 corresponding to the first character of the input will appear on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6954 lookahead line. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6955 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6956 If you click Single Step after selecting a token from �Allowable |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6957 Input� and it causes only a simple �reduce action� (as opposed to a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6958 shift or a compound action), then, upon completion of the reduction, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6959 the token you selected will appear on the lookahead line and also |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6960 will be preselected in Allowable Input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6961 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6962 Usually you would select |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6963 this token for the next parse step. However, if there are other |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6964 possible inputs in this state, the parse theoretically could have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6965 arrived at this state by a different sequence of input tokens. Thus, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6966 if you are more interested in the behavior of the parser at this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6967 state than in the response of the parser to a particular sequence of |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6968 inputs, it is perfectly valid to select a different input token, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6969 AnaGram will let you do it. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6970 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6971 Note that if you have enabled the �traditional engine� switch or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6972 disabled the �default reductions� switch, the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6973 probability of finding a token which does a simple reduction is |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6974 noticeably higher than otherwise. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6975 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6976 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6977 Action Menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6978 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6979 The Action menu begins with the �Analyze Grammar� and �Build Parser� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6980 commands. If a grammar has already been analyzed, but not yet built, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6981 there will also be an extra Build command bearing the name of your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6982 syntax file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6983 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6984 There are also �Reanalyze� and �Rebuild� commands which are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6985 initially greyed out. They become available if you change the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6986 current syntax file. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6987 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6988 The next section has �File Trace� and �Grammar Trace� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6989 commands. If you have enabled the �Error Trace� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6990 �configuration switch�, this section also shows an |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6991 Error Trace command. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6992 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6993 The menu ends with an �Exit� command |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6994 and a list of recently used syntax files, if any. Just |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6995 click on a syntax file name to have AnaGram analyze it, or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6996 build it if the �Autobuild� option is on. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6997 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6998 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
6999 Browse Menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7000 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7001 Initially, the Browse Menu shows only a single entry: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7002 �Configuration Parameters� which lets you see the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7003 current state of configuration parameters before any |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7004 may have been set by your syntax file. Once you have |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7005 analyzed a grammar, this menu fills up with many tables |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7006 containing information about your grammar. You can also |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7007 bring up a window showing your �syntax file� from this menu. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7008 If your grammar has generated �syntax error�s or warnings, or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7009 contains conflicts, there will be �Warning�s or �Conflict�s |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7010 entries. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7011 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7012 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7013 Options Menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7014 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7015 From this menu you can select a �Fonts� or �Colors� dialog so you can |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7016 set AnaGram's fonts and colors to suit your own tastes. You can set |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7017 �Autobuild� if you want AnaGram to automatically build your �grammar� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7018 when you select a �syntax file� from the �Action Menu�. You can also |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7019 choose whether or not to automatically show the �Statistical Summary� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7020 window or your syntax file window when you open a grammar, or make |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7021 the �Control Panel� stay on top of other AnaGram windows. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7022 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7023 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7024 Windows Menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7025 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7026 The Windows menu lets you cascade, close, or hide all AnaGram |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7027 windows except the �Control Panel�, or restore them if they |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7028 have been hidden. It also has a list of open windows (even |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7029 if hidden) so you can select the one you want. The Copy command will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7030 copy most windows to the clipboard. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7031 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7032 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7033 Help Menu |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7034 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7035 The Help Menu has the following entries: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7036 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7037 �Getting Started� provides a brief description of AnaGram and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7038 introductory suggestions. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7039 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7040 �Help Topics� brings up a list of all help topics. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7041 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7042 �Using Help� tells you how to use AnaGram's help facilities. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7043 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7044 �What's New� has information on new features of this version of AnaGram. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7045 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7046 �About AnaGram� tells you what version of AnaGram you are using, and also |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7047 provides contact information for Parsifal Software. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7048 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7049 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7050 Autobuild |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7051 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7052 When Autobuild (�Options Menu�) is checked, selecting a file |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7053 from the list of most recently used files on the �Action Menu� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7054 invokes the �Build Parser� command. Otherwise, the �Analyze |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7055 Grammar� command is invoked. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7056 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7057 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7058 Reanalyze, Rebuild |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7059 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7060 Reanalyze and Rebuild commands on the �Action Menu� are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7061 initially greyed out. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7062 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7063 Reanalyze becomes available if |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7064 you have a syntax file currently analyzed or built |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7065 in AnaGram and change it while AnaGram is still running. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7066 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7067 Rebuild becomes available if |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7068 you have a syntax file currently built |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7069 and change it while AnaGram is still running. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7070 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7071 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7072 Percent Sign |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7073 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7074 The percent sign ( % ) is used to mark certain tokens in your grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7075 which AnaGram must redefine in order to implement the �disregard� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7076 statement. If you have used this statement in your grammar, You will |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7077 probably notice the percent sign appearing in some windows and traces. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7078 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7079 The percent sign indicates the original token, without the optional |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7080 white space attached. Early versions of AnaGram used the degree sign |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7081 instead, but this character is not generally available in Windows. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7082 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7083 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7084 Program Development |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7085 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7086 The first step in writing a program is to write a �grammar� in |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7087 AnaGram notation which describes the input the program expects. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7088 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7089 The file containing the grammar, called the �syntax file�, should |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7090 have the extension ".syn". You could also make up a few sample input |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7091 files at this time, but it is not necessary to write �reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7092 procedure�s at this stage. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7093 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7094 Run AnaGram and use the �Analyze Grammar� command to create parse |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7095 tables. If there are �syntax errors� in the grammar at this point, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7096 you will have to correct them before proceeding, but you do not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7097 necessarily have to eliminate �conflicts�, if there are any, at this |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7098 time. There are, however, many aids available to help you with |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7099 conflicts. These aids are described in the AnaGram User's Guide, and |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7100 somewhat more briefly in the Online Help topics. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7101 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7102 Once syntax errors are corrected, you can try out your grammar on the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7103 sample input files using the �File Trace� facility. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7104 With File Trace, you can see interactively just how your grammar |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7105 operates on your test files. You can also use �Grammar Trace� to |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7106 answer "what if" questions concerning input to the grammar. The |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7107 Grammar Trace does not use a test file, but rather allows you to make |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7108 input choices interactively. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7109 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7110 At any time, you can write �reduction procedure�s to process your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7111 input data as its components are identified in the input stream. Each |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7112 procedure is associated with a �grammar rule�. The reduction |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7113 procedures will be incorporated into your parser when you create it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7114 with the �Build Parser� command. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7115 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7116 By default, unless you specify an input procedure, �parser input� |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7117 will be read from stdin, using the default �GET_INPUT� macro. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7118 You will probably wish to redefine GET_INPUT, or configure your |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7119 parser to use �pointer input� or �event driven� input. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7120 ## |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7121 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7122 License, Copyright, Copying, Open Source, Warranty, No Warranty |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7123 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7124 AnaGram, A System for Syntax Directed Programming |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7125 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7126 Copyright 1993-2002 Parsifal Software |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7127 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7128 Copyright 2006, 2007 David A. Holland |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7129 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7130 All Rights Reserved. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7131 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7132 AnaGram itself is released to the public under the traditional 4-clause BSD |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7133 license: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7134 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7135 Redistribution and use in source and binary forms, with or without |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7136 modification, are permitted provided that the following conditions are |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7137 met: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7138 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7139 1. Redistributions of source code must retain the above copyright notice, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7140 this list of conditions and the following disclaimer. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7141 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7142 2. Redistributions in binary form must reproduce the above copyright |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7143 notice, this list of conditions and the following disclaimer in the |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7144 documentation and/or other materials provided with the distribution. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7145 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7146 3. All advertising materials mentioning features or use of this software |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7147 must display the following acknowledgement: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7148 This product includes software developed by Parsifal Software, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7149 Jerome T. Holland, and their contributors. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7150 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7151 4. Neither the name of Parsifal Software nor the name of Jerome T. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7152 Holland nor the names of their contributors may be used to endorse or |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7153 promote products derived from this software without specific prior written |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7154 permission. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7155 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7156 THIS SOFTWARE IS PROVIDED BY PARSIFAL SOFTWARE, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7157 JEROME T. HOLLAND, AND CONTRIBUTORS ``AS IS'' AND ANY |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7158 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7159 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7160 AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7161 IN NO EVENT SHALL PARSIFAL SOFTWARE, JEROME T. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7162 HOLLAND, OR THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7163 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7164 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7165 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7166 USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7167 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7168 WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7169 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7170 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7171 POSSIBILITY OF SUCH DAMAGE. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7172 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7173 The AnaGram �parsing engine�, that is, the code that is emitted by |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7174 AnaGram and incorporated into programs developed using AnaGram, uses |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7175 this less restrictive zlib-style license: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7176 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7177 This software is provided 'as-is', without any express or implied warranty. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7178 In no event will the authors be held liable for any damages arising from |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7179 the use of this software. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7180 |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
7181 Permission is granted to anyone to use this software for any purpose, |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7182 including commercial applications, and to alter it and redistribute it |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7183 freely, subject to the following restrictions: |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7184 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7185 1. The origin of this software must not be misrepresented; you must not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7186 claim that you wrote the original software. If you use this software in a |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7187 product, an acknowledgment in the product documentation would be |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7188 appreciated but is not required. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7189 |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
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|
7190 2. Altered source versions must be plainly marked as such, and must not |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7191 be misrepresented as being the original software. |
|
13d2b8934445
Import AnaGram (near-)release tree into Mercurial.
David A. Holland
parents:
diff
changeset
|
7192 |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
7193 3. This notice may not be removed or altered from any source distribution. |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
7194 |
|
13d2b8934445
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David A. Holland
parents:
diff
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|
7195 ## |