parser.l

%{
    #include "y.tab.h"

    void yyerror (char *s);
    int yylex();
%}

%%

    /* Whitespace */
[ \t\n]     ;

"print"       return print;
"exit"      return exit_cmd;

[a-zA-Z\_][a-zA-Z0-9\_]* {yylval.str = yytext; printf("Identifier `%s` found\n", yytext); return identifier;}
[\'\"].*?[\'\"]        {yylval.str = yytext; return string;}
[0-9]+                   {yylval.num = atoi(yytext); return number;}

[\=\-\+\/\*\^]     return yytext[0];

.                  {fprintf(stderr, "Unexpected character `%s` \n", yytext);}

%%

int yywrap(void) {return 1;}