expr.y


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%{
/* $Id: expr.y,v 1.2 2006/11/05 04:42:43 ganzhorn Exp $
 * This file is part of lfhex.
 * Copyright (C) 2006 Salem Ganzhorn <eyekode@yahoo.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation version 2.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */  
#define YYSTYPE off_t
#include <iostream>

#include <math.h>

#include "expr.h"

using namespace std;

off_t expr_value;

int exprlex();

static int exprerror( const char * );

%}

%token NUMBER
%left '-' '+' '*' '/'

%%
target : expr {
   expr_value = $1;
}
;

expr: /* nothing */
| NUMBER        { $$ = $1; }
| expr '+' expr { $$ = $1 + $3; }
| expr '-' expr { $$ = $1 - $3; }
| expr '*' expr { $$ = $1 * $3; }
| '(' expr ')'  { $$ = $2; }
;


%%

static int 
exprerror( 
   const char * str
   )
{
   return 0;
}