public static function get_instance() { if (!(self::$checkout_controller && is_a(self::$checkout_controller, __CLASS__))) { self::$checkout_controller = new self(); } return self::$checkout_controller; }
public static function get_instance() { if (!(self::$checkout_controller && is_a(self::$checkout_controller, __CLASS__))) { self::$checkout_controller = new self(); } return self::$checkout_controller; }