calc.l

/** 171517
 * calculator calc.l
 * origin source by Tom Niemann at epaperpress.com/lexandyacc
 * revision Lorenzo Massimo Gramola (2014)
 * revision Lorenzo Massimo Gramola (2015)
 * revision Lorenzo Massimo Gramola (2016)
 */
%{
    #include <stdlib.h>
    #include "calc.h"
    #include "y.tab.h"

    void yyerror(char *);
%}

%%

"while"         return WHILE;
"if"            return IF;
"else"          return ELSE;
"print"         return PRINT;

[a-z][a-z0-9]*  {
                    int l=0;
                    int i=0;
                    for(; yytext[l] != '\0'; l++){
                    }
                    yylval.sIndex = malloc((l+1)*sizeof(char));
                    for(i=0; yytext[i] != '\0'; i++){
                        yylval.sIndex[i]=yytext[i];
                    }
                    yylval.sIndex[l]='\0';

                    return VARIABLE;
                }
0               {
                    yylval.iValue = atoi(yytext);
                    return INTEGER;
                }
[1-9][0-9]*     {
                    yylval.iValue = atoi(yytext);
                    return INTEGER;
                }

[-+()<>=*/;{}.@]   { return *yytext; }

">="            return GE;
"<="            return LE;
"=="            return EQ;
"!="            return NE;



[ \t\n]         ;/* skip whitespace */

.               yyerror("Unknown character");

%%

int yywrap(void) {
    return 1;
}