1 | /*
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2 | * Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
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3 | *
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4 | * The contents of this file are covered under the licence agreement in the
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5 | * file "LICENCE" distributed with Cforall.
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6 | *
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7 | * lex.l --
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8 | *
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9 | * Author : Peter A. Buhr
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10 | * Created On : Sat Sep 22 08:58:10 2001
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11 | * Last Modified By : Peter A. Buhr
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12 | * Last Modified On : Sun May 31 23:41:32 2015
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13 | * Update Count : 334
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14 | */
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15 |
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16 | %option yylineno
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17 |
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18 | %{
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19 | // This lexer assumes the program has been preprocessed by cpp. Hence, all user level preprocessor directive
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20 | // have been performed and removed from the source. The only exceptions are preprocessor directives passed to
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21 | // the compiler (e.g., line-number directives) and C/C++ style comments, which are ignored.
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22 |
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23 | //**************************** Includes and Defines ****************************
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24 |
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25 | #include <string>
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26 |
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27 | #include "lex.h"
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28 | #include "ParseNode.h"
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29 | #include "parser.h" // YACC generated definitions based on C++ grammar
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30 |
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31 | char *yyfilename;
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32 | std::string *strtext; // accumulate parts of character and string constant value
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33 |
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34 | #define WHITE_RETURN(x) // do nothing
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35 | #define NEWLINE_RETURN() WHITE_RETURN('\n')
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36 | #define RETURN_VAL(x) yylval.tok.str = new std::string(yytext); \
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37 | yylval.tok.loc.file = yyfilename; \
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38 | yylval.tok.loc.line = yylineno; \
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39 | return(x)
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40 | #define RETURN_STR(x) yylval.tok.str = strtext; \
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41 | yylval.tok.loc.file = yyfilename; \
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42 | yylval.tok.loc.line = yylineno; \
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43 | return(x)
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44 |
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45 | #define KEYWORD_RETURN(x) RETURN_VAL(x) // keyword
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46 | #define IDENTIFIER_RETURN() RETURN_VAL((typedefTable.isIdentifier(yytext) ? IDENTIFIER : typedefTable.isTypedef(yytext) ? TYPEDEFname : TYPEGENname))
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47 | //#define ATTRIBUTE_RETURN() RETURN_VAL((typedefTable.isIdentifier(yytext) ? ATTR_IDENTIFIER : typedefTable.isTypedef(yytext) ? ATTR_TYPEDEFname : ATTR_TYPEGENname))
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48 | #define ATTRIBUTE_RETURN() RETURN_VAL(ATTR_IDENTIFIER)
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49 |
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50 | #define ASCIIOP_RETURN() RETURN_VAL((int)yytext[0]) // single character operator
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51 | #define NAMEDOP_RETURN(x) RETURN_VAL(x) // multichar operator, with a name
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52 |
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53 | #define NUMERIC_RETURN(x) rm_underscore(); RETURN_VAL(x) // numeric constant
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54 |
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55 | void rm_underscore() {
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56 | // remove underscores in numeric constant
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57 | int j = 0;
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58 | for ( int i = 0; yytext[i] != '\0'; i += 1 ) {
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59 | if ( yytext[i] != '_' ) {
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60 | yytext[j] = yytext[i];
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61 | j += 1;
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62 | } // if
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63 | } // for
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64 | yyleng = j;
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65 | yytext[yyleng] = '\0';
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66 | }
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67 |
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68 | %}
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69 |
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70 | octal [0-7]
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71 | nonzero [1-9]
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72 | decimal [0-9]
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73 | hex [0-9a-fA-F]
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74 | universal_char "\\"((u"_"?{hex_quad})|(U"_"?{hex_quad}{2}))
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75 |
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76 | // identifier, GCC: $ in identifier
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77 | identifier ([a-zA-Z_$]|{universal_char})([0-9a-zA-Z_$]|{universal_char})*
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78 |
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79 | // quoted identifier
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80 | quoted_identifier "`"{identifier}"`"
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81 |
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82 | // attribute identifier, GCC: $ in identifier
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83 | attr_identifier "@"{identifier}
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84 |
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85 | // numeric constants, CFA: '_' in constant
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86 | hex_quad {hex}("_"?{hex}){3}
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87 | integer_suffix "_"?(([uU][lL]?)|([uU]("ll"|"LL")?)|([lL][uU]?)|("ll"|"LL")[uU]?)
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88 |
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89 | octal_digits ({octal})|({octal}({octal}|"_")*{octal})
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90 | octal_prefix "0""_"?
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91 | octal_constant (("0")|({octal_prefix}{octal_digits})){integer_suffix}?
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92 |
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93 | nonzero_digits ({nonzero})|({nonzero}({decimal}|"_")*{decimal})
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94 | decimal_constant {nonzero_digits}{integer_suffix}?
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95 |
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96 | hex_digits ({hex})|({hex}({hex}|"_")*{hex})
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97 | hex_prefix "0"[xX]"_"?
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98 | hex_constant {hex_prefix}{hex_digits}{integer_suffix}?
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99 |
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100 | decimal_digits ({decimal})|({decimal}({decimal}|"_")*{decimal})
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101 | fractional_constant ({decimal_digits}?"."{decimal_digits})|({decimal_digits}".")
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102 | exponent "_"?[eE]"_"?[+-]?{decimal_digits}
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103 | floating_suffix "_"?[flFL]
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104 | floating_constant (({fractional_constant}{exponent}?)|({decimal_digits}{exponent})){floating_suffix}?
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105 |
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106 | binary_exponent "_"?[pP]"_"?[+-]?{decimal_digits}
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107 | hex_fractional_constant ({hex_digits}?"."{hex_digits})|({hex_digits}".")
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108 | hex_floating_constant {hex_prefix}(({hex_fractional_constant}{binary_exponent})|({hex_digits}{binary_exponent})){floating_suffix}?
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109 |
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110 | // character escape sequence, GCC: \e => esc character
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111 | simple_escape "\\"[abefnrtv'"?\\]
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112 | // ' stop highlighting
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113 | octal_escape "\\"{octal}("_"?{octal}){0,2}
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114 | hex_escape "\\""x""_"?{hex_digits}
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115 | escape_seq {simple_escape}|{octal_escape}|{hex_escape}|{universal_char}
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116 |
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117 | // display/white-space characters
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118 | h_tab [\011]
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119 | form_feed [\014]
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120 | v_tab [\013]
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121 | c_return [\015]
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122 | h_white [ ]|{h_tab}
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123 |
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124 | // operators
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125 | op_unary_only "~"|"!"
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126 | op_unary_binary "+"|"-"|"*"
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127 | op_unary_pre_post "++"|"--"
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128 | op_unary {op_unary_only}|{op_unary_binary}|{op_unary_pre_post}
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129 |
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130 | op_binary_only "/"|"%"|"^"|"&"|"|"|"<"|">"|"="|"=="|"!="|"<<"|">>"|"<="|">="|"+="|"-="|"*="|"/="|"%="|"&="|"|="|"^="|"<<="|">>="
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131 | op_binary_over {op_unary_binary}|{op_binary_only}
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132 | op_binary_not_over "?"|"->"|"&&"|"||"
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133 | operator {op_unary_pre_post}|{op_binary_over}|{op_binary_not_over}
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134 |
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135 | %x COMMENT
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136 | %x BKQUOTE
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137 | %x QUOTE
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138 | %x STRING
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139 |
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140 | %%
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141 | /* line directives */
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142 | ^{h_white}*"#"{h_white}*[0-9]+{h_white}*["][^"\n]+["][^\n]*"\n" {
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143 | /* " stop highlighting */
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144 | char *end_num;
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145 | char *begin_string, *end_string;
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146 | char *filename;
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147 | long lineno, length;
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148 | lineno = strtol( yytext + 1, &end_num, 0 );
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149 | begin_string = strchr( end_num, '"' );
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150 | if ( begin_string ) {
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151 | end_string = strchr( begin_string + 1, '"' );
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152 | if ( end_string ) {
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153 | length = end_string - begin_string - 1;
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154 | filename = new char[ length + 1 ];
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155 | memcpy( filename, begin_string + 1, length );
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156 | filename[ length ] = '\0';
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157 | //std::cout << "file " << filename << " line " << lineno << std::endl;
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158 | yylineno = lineno;
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159 | yyfilename = filename;
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160 | } // if
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161 | } // if
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162 | }
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163 |
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164 | /* ignore preprocessor directives (for now) */
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165 | ^{h_white}*"#"[^\n]*"\n" ;
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166 |
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167 | /* ignore C style comments */
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168 | "/*" { BEGIN COMMENT; }
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169 | <COMMENT>.|\n ;
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170 | <COMMENT>"*/" { BEGIN 0; }
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171 |
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172 | /* ignore C++ style comments */
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173 | "//"[^\n]*"\n" ;
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174 |
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175 | /* ignore whitespace */
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176 | {h_white}+ { WHITE_RETURN(' '); }
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177 | ({v_tab}|{c_return}|{form_feed})+ { WHITE_RETURN(' '); }
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178 | ({h_white}|{v_tab}|{c_return}|{form_feed})*"\n" { NEWLINE_RETURN(); }
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179 |
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180 | /* keywords */
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181 | _Alignas { KEYWORD_RETURN(ALIGNAS); } // C11
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182 | _Alignof { KEYWORD_RETURN(ALIGNOF); } // C11
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183 | __alignof { KEYWORD_RETURN(ALIGNOF); } // GCC
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184 | __alignof__ { KEYWORD_RETURN(ALIGNOF); } // GCC
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185 | asm { KEYWORD_RETURN(ASM); }
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186 | __asm { KEYWORD_RETURN(ASM); } // GCC
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187 | __asm__ { KEYWORD_RETURN(ASM); } // GCC
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188 | _Atomic { KEYWORD_RETURN(ATOMIC); } // C11
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189 | __attribute { KEYWORD_RETURN(ATTRIBUTE); } // GCC
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190 | __attribute__ { KEYWORD_RETURN(ATTRIBUTE); } // GCC
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191 | auto { KEYWORD_RETURN(AUTO); }
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192 | _Bool { KEYWORD_RETURN(BOOL); } // C99
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193 | break { KEYWORD_RETURN(BREAK); }
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194 | case { KEYWORD_RETURN(CASE); }
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195 | catch { KEYWORD_RETURN(CATCH); } // CFA
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196 | char { KEYWORD_RETURN(CHAR); }
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197 | choose { KEYWORD_RETURN(CHOOSE); } // CFA
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198 | _Complex { KEYWORD_RETURN(COMPLEX); } // C99
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199 | __complex { KEYWORD_RETURN(COMPLEX); } // GCC
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200 | __complex__ { KEYWORD_RETURN(COMPLEX); } // GCC
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201 | const { KEYWORD_RETURN(CONST); }
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202 | __const { KEYWORD_RETURN(CONST); } // GCC
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203 | __const__ { KEYWORD_RETURN(CONST); } // GCC
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204 | context { KEYWORD_RETURN(CONTEXT); } // CFA
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205 | continue { KEYWORD_RETURN(CONTINUE); }
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206 | default { KEYWORD_RETURN(DEFAULT); }
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207 | do { KEYWORD_RETURN(DO); }
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208 | double { KEYWORD_RETURN(DOUBLE); }
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209 | dtype { KEYWORD_RETURN(DTYPE); } // CFA
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210 | else { KEYWORD_RETURN(ELSE); }
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211 | enum { KEYWORD_RETURN(ENUM); }
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212 | __extension__ { KEYWORD_RETURN(EXTENSION); } // GCC
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213 | extern { KEYWORD_RETURN(EXTERN); }
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214 | fallthru { KEYWORD_RETURN(FALLTHRU); } // CFA
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215 | finally { KEYWORD_RETURN(FINALLY); } // CFA
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216 | float { KEYWORD_RETURN(FLOAT); }
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217 | __float128 { KEYWORD_RETURN(FLOAT); } // GCC
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218 | for { KEYWORD_RETURN(FOR); }
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219 | forall { KEYWORD_RETURN(FORALL); } // CFA
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220 | fortran { KEYWORD_RETURN(FORTRAN); }
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221 | ftype { KEYWORD_RETURN(FTYPE); } // CFA
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222 | _Generic { KEYWORD_RETURN(GENERIC); } // C11
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223 | goto { KEYWORD_RETURN(GOTO); }
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224 | if { KEYWORD_RETURN(IF); }
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225 | _Imaginary { KEYWORD_RETURN(IMAGINARY); } // C99
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226 | __imag { KEYWORD_RETURN(IMAGINARY); } // GCC
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227 | __imag__ { KEYWORD_RETURN(IMAGINARY); } // GCC
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228 | inline { KEYWORD_RETURN(INLINE); } // C99
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229 | __inline { KEYWORD_RETURN(INLINE); } // GCC
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230 | __inline__ { KEYWORD_RETURN(INLINE); } // GCC
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231 | int { KEYWORD_RETURN(INT); }
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232 | __int128 { KEYWORD_RETURN(INT); } // GCC
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233 | __label__ { KEYWORD_RETURN(LABEL); } // GCC
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234 | long { KEYWORD_RETURN(LONG); }
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235 | lvalue { KEYWORD_RETURN(LVALUE); } // CFA
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236 | _Noreturn { KEYWORD_RETURN(NORETURN); } // C11
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237 | register { KEYWORD_RETURN(REGISTER); }
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238 | restrict { KEYWORD_RETURN(RESTRICT); } // C99
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239 | __restrict { KEYWORD_RETURN(RESTRICT); } // GCC
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240 | __restrict__ { KEYWORD_RETURN(RESTRICT); } // GCC
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241 | return { KEYWORD_RETURN(RETURN); }
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242 | short { KEYWORD_RETURN(SHORT); }
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243 | signed { KEYWORD_RETURN(SIGNED); }
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244 | __signed { KEYWORD_RETURN(SIGNED); } // GCC
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245 | __signed__ { KEYWORD_RETURN(SIGNED); } // GCC
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246 | sizeof { KEYWORD_RETURN(SIZEOF); }
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247 | static { KEYWORD_RETURN(STATIC); }
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248 | _Static_assert { KEYWORD_RETURN(STATICASSERT); } // C11
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249 | struct { KEYWORD_RETURN(STRUCT); }
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250 | switch { KEYWORD_RETURN(SWITCH); }
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251 | _Thread_local { KEYWORD_RETURN(THREADLOCAL); } // C11
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252 | throw { KEYWORD_RETURN(THROW); } // CFA
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253 | try { KEYWORD_RETURN(TRY); } // CFA
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254 | type { KEYWORD_RETURN(TYPE); } // CFA
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255 | typedef { KEYWORD_RETURN(TYPEDEF); }
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256 | typeof { KEYWORD_RETURN(TYPEOF); } // GCC
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257 | __typeof { KEYWORD_RETURN(TYPEOF); } // GCC
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258 | __typeof__ { KEYWORD_RETURN(TYPEOF); } // GCC
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259 | union { KEYWORD_RETURN(UNION); }
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260 | unsigned { KEYWORD_RETURN(UNSIGNED); }
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261 | void { KEYWORD_RETURN(VOID); }
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262 | volatile { KEYWORD_RETURN(VOLATILE); }
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263 | __volatile { KEYWORD_RETURN(VOLATILE); } // GCC
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264 | __volatile__ { KEYWORD_RETURN(VOLATILE); } // GCC
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265 | while { KEYWORD_RETURN(WHILE); }
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266 |
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267 | /* identifier */
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268 | {identifier} { IDENTIFIER_RETURN(); }
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269 | {attr_identifier} { ATTRIBUTE_RETURN(); }
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270 | "`" { BEGIN BKQUOTE; }
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271 | <BKQUOTE>{identifier} { IDENTIFIER_RETURN(); }
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272 | <BKQUOTE>"`" { BEGIN 0; }
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273 |
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274 | /* numeric constants */
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275 | "0" { NUMERIC_RETURN(ZERO); } // CFA
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276 | "1" { NUMERIC_RETURN(ONE); } // CFA
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277 | {decimal_constant} { NUMERIC_RETURN(INTEGERconstant); }
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278 | {octal_constant} { NUMERIC_RETURN(INTEGERconstant); }
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279 | {hex_constant} { NUMERIC_RETURN(INTEGERconstant); }
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280 | {floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
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281 | {hex_floating_constant} { NUMERIC_RETURN(FLOATINGconstant); }
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282 |
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283 | /* character constant, allows empty value */
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284 | "L"?"_"?['] { BEGIN QUOTE; rm_underscore(); strtext = new std::string; *strtext += std::string( yytext ); }
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285 | <QUOTE>[^'\\\n]* { *strtext += std::string( yytext ); }
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286 | <QUOTE>['\n] { BEGIN 0; *strtext += std::string( yytext); RETURN_STR(CHARACTERconstant); }
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287 | /* ' stop highlighting */
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288 |
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289 | /* string constant */
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290 | "L"?"_"?["] { BEGIN STRING; rm_underscore(); strtext = new std::string; *strtext += std::string( yytext ); }
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291 | <STRING>[^"\\\n]* { *strtext += std::string( yytext ); }
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292 | <STRING>["\n] { BEGIN 0; *strtext += std::string( yytext); RETURN_STR(STRINGliteral); }
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293 | /* " stop highlighting */
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294 |
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295 | <QUOTE,STRING>{escape_seq} { rm_underscore(); *strtext += std::string( yytext ); }
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296 | <QUOTE,STRING>[\\] { *strtext += std::string( yytext ); } // unknown escape character
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297 |
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298 | /* punctuation */
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299 | "[" { ASCIIOP_RETURN(); }
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300 | "]" { ASCIIOP_RETURN(); }
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301 | "(" { ASCIIOP_RETURN(); }
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302 | ")" { ASCIIOP_RETURN(); }
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303 | "{" { ASCIIOP_RETURN(); }
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304 | "}" { ASCIIOP_RETURN(); }
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305 | "," { ASCIIOP_RETURN(); } // also operator
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306 | ":" { ASCIIOP_RETURN(); }
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307 | ";" { ASCIIOP_RETURN(); }
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308 | "." { ASCIIOP_RETURN(); } // also operator
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309 | "..." { NAMEDOP_RETURN(ELLIPSIS); }
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310 |
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311 | /* alternative C99 brackets, "<:" & "<:<:" handled by preprocessor */
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312 | "<:" { RETURN_VAL('['); }
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313 | ":>" { RETURN_VAL(']'); }
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314 | "<%" { RETURN_VAL('{'); }
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315 | "%>" { RETURN_VAL('}'); }
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316 |
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317 | /* operators */
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318 | "!" { ASCIIOP_RETURN(); }
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319 | "+" { ASCIIOP_RETURN(); }
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320 | "-" { ASCIIOP_RETURN(); }
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321 | "*" { ASCIIOP_RETURN(); }
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322 | "/" { ASCIIOP_RETURN(); }
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323 | "%" { ASCIIOP_RETURN(); }
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324 | "^" { ASCIIOP_RETURN(); }
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325 | "~" { ASCIIOP_RETURN(); }
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326 | "&" { ASCIIOP_RETURN(); }
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327 | "|" { ASCIIOP_RETURN(); }
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328 | "<" { ASCIIOP_RETURN(); }
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329 | ">" { ASCIIOP_RETURN(); }
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330 | "=" { ASCIIOP_RETURN(); }
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331 | "?" { ASCIIOP_RETURN(); }
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332 |
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333 | "++" { NAMEDOP_RETURN(ICR); }
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334 | "--" { NAMEDOP_RETURN(DECR); }
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335 | "==" { NAMEDOP_RETURN(EQ); }
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336 | "!=" { NAMEDOP_RETURN(NE); }
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337 | "<<" { NAMEDOP_RETURN(LS); }
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338 | ">>" { NAMEDOP_RETURN(RS); }
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339 | "<=" { NAMEDOP_RETURN(LE); }
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340 | ">=" { NAMEDOP_RETURN(GE); }
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341 | "&&" { NAMEDOP_RETURN(ANDAND); }
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342 | "||" { NAMEDOP_RETURN(OROR); }
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343 | "->" { NAMEDOP_RETURN(ARROW); }
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344 | "+=" { NAMEDOP_RETURN(PLUSassign); }
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345 | "-=" { NAMEDOP_RETURN(MINUSassign); }
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346 | "*=" { NAMEDOP_RETURN(MULTassign); }
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347 | "/=" { NAMEDOP_RETURN(DIVassign); }
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348 | "%=" { NAMEDOP_RETURN(MODassign); }
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349 | "&=" { NAMEDOP_RETURN(ANDassign); }
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350 | "|=" { NAMEDOP_RETURN(ORassign); }
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351 | "^=" { NAMEDOP_RETURN(ERassign); }
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352 | "<<=" { NAMEDOP_RETURN(LSassign); }
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353 | ">>=" { NAMEDOP_RETURN(RSassign); }
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354 |
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355 | /* CFA, operator identifier */
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356 | {op_unary}"?" { IDENTIFIER_RETURN(); } // unary
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357 | "?"({op_unary_pre_post}|"()"|"[?]") { IDENTIFIER_RETURN(); }
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358 | "?"{op_binary_over}"?" { IDENTIFIER_RETURN(); } // binary
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359 | /*
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360 | This rule handles ambiguous cases with operator identifiers, e.g., "int *?*?()", where the string "*?*?"
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361 | can be lexed as "*"/"?*?" or "*?"/"*?". Since it is common practise to put a unary operator juxtaposed
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362 | to an identifier, e.g., "*i", users will be annoyed if they cannot do this with respect to operator
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363 | identifiers. Even with this special hack, there are 5 general cases that cannot be handled. The first
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364 | case is for the function-call identifier "?()":
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365 |
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366 | int * ?()(); // declaration: space required after '*'
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367 | * ?()(); // expression: space required after '*'
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368 |
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369 | Without the space, the string "*?()" is ambiguous without N character look ahead; it requires scanning
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370 | ahead to determine if there is a '(', which is the start of an argument/parameter list.
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371 |
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372 | The 4 remaining cases occur in expressions:
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373 |
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374 | i++?i:0; // space required before '?'
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375 | i--?i:0; // space required before '?'
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376 | i?++i:0; // space required after '?'
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377 | i?--i:0; // space required after '?'
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378 |
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379 | In the first two cases, the string "i++?" is ambiguous, where this string can be lexed as "i"/"++?" or
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380 | "i++"/"?"; it requires scanning ahead to determine if there is a '(', which is the start of an argument
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381 | list. In the second two cases, the string "?++x" is ambiguous, where this string can be lexed as
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382 | "?++"/"x" or "?"/"++x"; it requires scanning ahead to determine if there is a '(', which is the start of
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383 | an argument list.
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384 | */
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385 | {op_unary}"?"(({op_unary_pre_post}|"[?]")|({op_binary_over}"?")) {
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386 | // 1 or 2 character unary operator ?
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387 | int i = yytext[1] == '?' ? 1 : 2;
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388 | yyless( i ); // put back characters up to first '?'
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389 | if ( i > 1 ) {
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390 | NAMEDOP_RETURN( yytext[0] == '+' ? ICR : DECR );
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391 | } else {
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392 | ASCIIOP_RETURN();
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393 | } // if
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394 | }
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395 |
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396 | /* unknown characters */
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397 | . { printf("unknown character(s):\"%s\" on line %d\n", yytext, yylineno); }
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398 |
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399 | %%
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400 |
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401 | // Local Variables: //
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402 | // fill-column: 110 //
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403 | // tab-width: 4 //
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404 | // mode: c++ //
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405 | // compile-command: "make install" //
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406 | // End: //
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