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run code in 300+ PHP versions simultaneously
<?php class foo { private $private = 'private'; protected $protected = 'protected'; public $public = 'public'; } class bar extends foo { public function __sleep() { return array("\0foo\0private", 'protected', 'public'); } } var_dump(str_replace("\0", '\0', serialize(new bar())));

preferences:
39.06 ms | 402 KiB | 5 Q