Note that PHP extensions also provide interfaces you can implement, for example JsonSerializable.
Here is the full list http://php.net/manual/en/refs.basic.other.php
Смотрите также Интерфейсы SPL и Предопределённые классы.
Note that PHP extensions also provide interfaces you can implement, for example JsonSerializable.
Here is the full list http://php.net/manual/en/refs.basic.other.php