/*
 * main.c
 *
 *  Created on: Dec 1, 2009
 *      Author: petergoodman
 *     Version: $Id$
 */

#include "lib/cfg.h"

int main(void) {

    cfg_t grammar = grammar_alloc(
        "Balanced Parens",
        1 /* # variables (excludes empty, includes start) */,
        2 /* # terminals */,
        3 /* # rewrite rules */
    );

    /* get all symbols that this grammar will need */
    cfg_term_t left_paren = cfg_term(grammar, "(");
    cfg_term_t right_paren = cfg_term(grammar, ")");
    cfg_var_t start = grammar_stvar(grammar);
    cfg_var_t empty = grammar_epvar(grammar);

    /* add production rewrite rules in reverse order */
    grammar_add_rule(start, 1, empty);
    grammar_add_rule(start, 3, left_paren, start, right_paren);
    grammar_add_rule(start, 2, start, start);

    grammar_fprint(grammar, stdout);

    grammar_free(grammar);

    return 0;
}