3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $x=array('a'=>null); var_dump(isset($x['a'], array_key_exists('a', $x));
Output for 5.3.0 - 5.4.1
Fatal error: Can't use function return value in write context in /in/d4HFH on line 4
Process exited with code 255.