protected function _conditions($step, $params, $data, $options) {
		if (!$conditions = $step['conditions']) {
			return true;
		}
		if (is_callable($conditions) && !$conditions($params, $data, $options)) {
			return false;
		}
		if (is_string($conditions) && !(isset($options[$conditions]) && $options[$conditions])) {
			return false;
		}
		return true;
	}