public function isset(string $name, int $type = null): bool
    {
        if (is_null($type)) {
            return array_key_exists($name, $this->options) || array_key_exists($name, self::$globalOptions);
        } else {
            if ($type == self::TYPE_GLOBAL) {
                return array_key_exists($name, self::$globalOptions);
            } else {
                return array_key_exists($name, $this->options);
            }
        }
    }