3v4l.org

run code in 300+ PHP versions simultaneously
<?php $foo = new \StdClass; $bar = new \StdClass; $foo->bar = $bar; $bar->foo = $foo; $vars = array('foo' => $foo, 'bar' => $bar); var_dump(serialize($vars));

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36.43 ms | 402 KiB | 5 Q