Rookie

[Werner Echezuria]

Hi,
I'm trying to parse words but I can't doing it. I read the manual, but I
still can't parse something like this: KEYWORD word word, Here is my code:

%{
#include <stdio.h>
%}

%union {
    char *string;
}

%token <string> KEYWORD DATA
%type <string> expr expresion

%%

input       : /* empty */
            | input line
;

line        : '\n'
            | expr '\n' { printf( "%s\n", $1 ); }
;

expr        : KEYWORD expresion  { $$ = $2; }
;

expresion   : DATA { $$ = $1; }
;

%%

#include <stdio.h>
#include <ctype.h>

main(){
    yyparse();
}

yyerror(char *str){
    printf("error= %s \n",str);
}

yylex(){
    int c;
    while((c=getchar())==' ' || c == '\t');

    if (c==EOF)
        return 0;

    if (isalpha (c))
    {
        static char *symbuf = 0;
        static int length = 0;
        int i;

        if (length == 0)
           length = 40, symbuf = (char *)malloc (length + 1);
        i = 0;
        do
           {
              if (i == length)
                {
                  length *= 2;
                  symbuf = (char *)realloc (symbuf, length + 1);
                }
              symbuf[i++] = c;

             c = getchar ();
           }
        while (c != EOF && isalnum (c));
        ungetc (c, stdin);
        symbuf[i] = '\0';
         yylval.string=symbuf;
        printf("%s \n",yylval.string);
        return KEYWORD;
    }

    return c;
}

thanks for any help.