3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $a ?? 'a' ?? 'b'; echo $a;
Output for 7.0.0 - 7.2.0
Notice: Undefined variable: a in /in/7mHfk on line 3
Output for 5.3.19 - 5.6.28
Parse error: syntax error, unexpected '?' in /in/7mHfk on line 2
Process exited with code 255.