3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $a = array_merge(array(4 => 2), array()); echo $a[4];
based on HvZqK
Output for 5.3.0 - 7.1.0
Notice: Undefined offset: 4 in /in/IDPSk on line 5
Output for 4.3.0 - 5.2.17
Notice: Undefined offset: 4 in /in/IDPSk on line 5