c_parser/src/c_lexer.flex


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%option noyywrap

%{
// Avoid error "error: fileno was not declared in this scope"
extern "C" int fileno(FILE *stream);

#include "c_parser.tab.hpp"

%}

%%
[*]             { return T_TIMES; }
[+]             { return T_PLUS; }
[/]             { return T_DIVIDE; }
[-]             { return T_MINUS; }

[(]             { return T_LBRACKET; }
[)]             { return T_RBRACKET; }

log             { return T_LOG;   }
exp             { return T_EXP; }
sqrt            { return T_SQRT; }

[-]?[0-9]+([.][0-9]*)? { yylval.number=strtod(yytext, 0); return T_NUMBER; }
[a-z]+          { yylval.string=new std::string(yytext); return T_VARIABLE; }

[ \t\r\n]+		{;}

.               { fprintf(stderr, "Invalid token\n"); exit(1); }
%%

void yyerror (char const *s)
{
  fprintf (stderr, "Parse error : %s\n", s);
  exit(1);
}