3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $arr = ['blah']; $key = 'foo'; $val = $arr[$key] ?? null; unset($arr[$key]); echo $val; var_dump($arr);
based on J4fpO
Output for 7.0.0 - 7.2.0
array(1) { [0]=> string(4) "blah" }
Output for 5.4.2 - 5.6.28
Parse error: syntax error, unexpected '?' in /in/9AcrU on line 6
Process exited with code 255.
Output for 5.3.18 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/9AcrU on line 3
Process exited with code 255.