scan.l

   1 %option noinput
   2 %option nounput
   3 %{
   4
   5 #include <stdio.h>
   6 #include "ast.h"
   7 #define YYSTYPE struct ast *
   8 #include "y.tab.h"
   9 extern YYSTYPE yylval;
  10
  11 %}
  12
  13 %%
  14
  15 if          return IF;
  16 else        return ELSE;
  17 while       return WHILE;
  18 var         return VAR;
  19 true        { yylval = ast_bool(true); return BOOL; }
  20 false       { yylval = ast_bool(false); return BOOL; }
  21 =           return ASSIGN;
  22 !           return INVERSE;
  23 \|\|        return BINOR;
  24 &&          return BINAND;
  25 ==          return EQ;
  26 !=          return NEQ;
  27 \<=         return GEQ;
  28 \<          return GE;
  29 >=          return LEQ;
  30 >           return LE;
  31 :           return CONS;
  32 \+          return PLUS;
  33 -           return MINUS;
  34 \*          return TIMES;
  35 \/          return DIVIDE;
  36 %           return MODULO;
  37 \^          return POWER;
  38 \(          return BOPEN;
  39 \)          return BCLOSE;
  40 \{          return COPEN;
  41 \}          return CCLOSE;
  42 \;          return SEMICOLON;
  43 ,           return COMMA;
  44 '([^']|\\[abtnvfr]|\\x[0-9a-fA-F]{2})' {
  45         yylval = ast_char(yytext);
  46         return CHAR;
  47 }
  48 [0-9]+      {
  49                 yylval = ast_int(atoi(yytext));
  50                 return INTEGER;
  51 }
  52 [_a-zA-Z][_a-zA-Z0-9]* {
  53                 yylval = ast_ident(yytext);
  54                 return IDENT;
  55 }
  56 [ \n\t]  ;
  57
  58 %%