3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php array_keys(array('a' => array('b' => 'b')));
based on U3rE2
Output for 4.3.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0