//call this syntax error when you are trying to parse the
//non-terminal nt, but you fail to find a token that you need
//to make progress. You should call this as soon as you can know
//there is a syntax_error.
void parser_t::syntax_error(nonterm_type nt)
{
printf("syntax error: found %s in parsing %s - line %d\n",
token_to_string( scanner.next_token()),
nonterm_to_string(nt),
scanner.get_line() );
exit(1);
}
void parser_t::div_by_zero_error()
{
printf("div by zero error: line %d\n", scanner.get_line() );
exit(0);
}