3v4l.org

run code in 300+ PHP versions simultaneously
<?php $x = new stdClass; $y = new stdClass; $y->foo = $x->foo = new stdClass; $x->foo->bar = 2; $xSer = serialize($x); $ySer = serialize($y); $x = unserialize($xSer); $y = unserialize($ySer); $x->foo->bar = 5; var_dump($y);

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47.37 ms | 402 KiB | 5 Q