Flex bison c++

%{
#include "lista4.tab.hpp"
#include <stdlib.h>
extern int yylex();
%}
%%
"=" {return EQ;}
"!="    {return NE;}
"<" {return LT;}
">" {return GT;}
":="    {return ASSIGN;}
";" {return SEMICOLON;}
"IF"    {return IF;}
"THEN"  {return THEN;}
"ELSE"  {return ELSE;}
"WHILE" {return WHILE;}
"DO"    {return DO;}
"PRINT" {return PRINT;}
"END"   {return END;}
[_a-z]+ {yylval.text = strdup(yytext); return IDENTIFIER;}
[ \t]+
[0-9]+          {
                yylval.var = atoi (yytext);
                return NUMBER;
                }
[-+/^*'%'()]    {
                return *yytext;
                }
\n              return RESULT;
%%



---------------------------------------------------------




%{
  extern "C"
  {
    int yyparse();
    int yylex(void);
    void yyerror(char *s){}
    int yywrap(void){return 1;}
  }

  #include <iostream>
  #include <vector>
  #include <string>
  #include <stdlib.h>
  #include <map>

  using namespace std;

  vector <string> instructions;
 // map <> vars;
%}

%union{
  char* text;
  int var;
}


%token EQ
%token NE
%token LT
%token GT
%token ASSIGN
%token SEMICOLON
%token IF
%token THEN
%token ELSE
%token WHILE
%token DO
%token PRINT
%token END
%token <text> IDENTIFIER
%token <var> NUMBER
%token <var> RESULT
%token READ
%token WRITE

%left '+' '-'
%left '*' '/' '%'
%right '^'


%%
//program: CONST cdeclarations VAR vdeclarations START commands END
//;

/*cdeclarations: cdeclarations IDENTIFIER EQ NUMBER
|
;

vdeclarations: vdeclarations IDENTIFIER
|
;

commands: commands command
|
;*/

/*command: IDENTIFIER ASSIGN exp SEMICOLON {}
| IF condition THEN commands ELSE commands END
| WHILE condition DO commands END
| READ IDENTIFIER SEMICOLON
| WRITE IDENTIFIER SEMICOLON
;*/

exp: NUMBER
| IDENTIFIER
| IDENTIFIER "+" IDENTIFIER
| IDENTIFIER "-" IDENTIFIER
| IDENTIFIER "*" IDENTIFIER
| IDENTIFIER "/" IDENTIFIER
| IDENTIFIER "%" IDENTIFIER
;
/*
condition: IDENTIFIER EQ IDENTIFIER
| IDENTIFIER NE IDENTIFIER
| IDENTIFIER LT IDENTIFIER
| IDENTIFIER GT IDENTIFIER
;*/

%%

int main(void){
 // FlexLexer* lexer = new yyFlexLexer;

 // while((lexer->yylex)!=0)
 // ;
  yyparse();
}


---------------------------------




#!/bin/bash
clear
rm launcher lex.yy.cpp *.tab.cpp *.tab.hpp
bison  -d -o lista4.tab.cpp *.y
flex -o lex.yy.cpp *.l
g++ -o launcher *.cpp -lfl