public static function data_for_messagearea_messages_parameters() {
        return new external_function_parameters(
            array(
                'currentuserid' => new external_value(PARAM_INT, 'The current user\'s id'),
                'otheruserid' => new external_value(PARAM_INT, 'The other user\'s id'),
                'limitfrom' => new external_value(PARAM_INT, 'Limit from', VALUE_DEFAULT, 0),
                'limitnum' => new external_value(PARAM_INT, 'Limit number', VALUE_DEFAULT, 0),
                'newest' => new external_value(PARAM_BOOL, 'Newest first?', VALUE_DEFAULT, false),
                'timefrom' => new external_value(PARAM_INT,
                    'The timestamp from which the messages were created', VALUE_DEFAULT, 0),
            )
        );
    }