Help please

[lookthree]

Hi,
I'm a new Flex user.
I'm having the follow problem:

1. I've created one file Example.l:

%option c++
%option yylineno
%option noyywrap
%option caseless

delim [ \t\n]
ws {delim}+
letter [A-Za-z]
digit [0-9]
id {letter}({letter}|{digit})*
number {digit}+(\.{digit}+)?(E[+\-]?{digit}+)?

%%
            int yylval;
{ws}        {;}
if          { return(IF);}
then        { return(THEN);}
else        { return(ELSE);}
{id}        { return(ID);}
{number}    { return(NUMBER);}
"<"         { yylval = LT; return(RELOP);}
"<="        { yylval = LE; return(RELOP);}
"="         { yylval = EQ; return(RELOP);}
"<>"        { yylval = NE; return(RELOP);}
">"         { yylval = GT; return(RELOP);}
">="        {yylval = GE; return(RELOP);}
.           {return(ERROR);}
%%


and i've run >Flex example.l

and it has returned the file lex.yy.cc.

2. Well, i've created also the main program in c++, let's call it main_prog.cpp:



#include <stdio.h>
#include <ctype.h>
enum {LT, LE, NE, GT, GE, EQ, IF, THEN, ELSE, ID, NUMBER, RELOP, ERROR};
#include <FlexLexer.h>
#include "lex.yy.cc"

int main(int argc, char *argv[])
{
    int token;
    FlexLexer* lexer = new yyFlexLexer();
    while ((token=lexer->yylex()) != 0) {
        switch (token) {
        case RELOP: printf("%s","RELOP"); break;
        case NUMBER: printf("%s","NUMBER"); break;
        case ID: printf("%s","ID"); break;
        case IF: printf("%s","IF"); break;
        case THEN: printf("%s","THEN"); break;
        case ELSE: printf("%s","ELSE");break;
        case ERROR: printf("%s", "illegal character"); break;
        default:
                    printf("%s","UNKNOWN");
                    break;
        }
        printf("%s\n", lexer->YYText());
    }
    return 0;
}

The problem becomes when I compile it using

        g++ main_prog.cpp -o main_prog

,infact the system answer me with:

/usr/include/FlexLexer.h:113: error: redefinition of ‘class yyFlexLexer’
/usr/include/FlexLexer.h:113: error: previous definition of ‘class yyFlexLexer’

thank you for helping me,

Simone.










**********
Scopri la nuova Alice Mail!
1 GB di spazio con antivirus, antispam e fino a 2 GB di allegati.

Registrati GRATIS su http://registra.rossoalice.alice.it/registra/basic/entratabasic.do?entryPoint=footer