flight-core/flight/util/LegacyJsonSerializable.php

<?php
/**
 * Flight: An extensible micro-framework.
 *
 * @copyright   Copyright (c) 2011, Mike Cao <mike@mikecao.com>
 * @license     MIT, http://flightphp.com/license
 */

interface JsonSerializable {
    public function jsonSerialize();
}