/** * Main U_Next_Story_Settings Instance * * Ensures only one instance of U_Next_Story_Settings is loaded or can be loaded. * * @since 1.0.0 * @static * @see U_Next_Story() * @return Main U_Next_Story_Settings instance */ public static function instance($parent) { if (is_null(self::$_instance)) { self::$_instance = new self($parent); } return self::$_instance; }