func (g *Grammar) RuleIsNullable(ruleid RuleID) int {
	return int(C.marpa_g_rule_is_nullable(g.handle, C.Marpa_Rule_ID(ruleid)))
}
func (g Grammar) RuleIsNullable(sym_id RuleID) int {
	return int(C.marpa_g_rule_is_nullable(g.grammar, sym_id.id))
}