3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $a = 'a'; echo $a ?? 'b';
based on LuK6J
Output for 7.0.0 - 7.2.0
a
Output for 5.4.0 - 5.6.28
Parse error: syntax error, unexpected '?' in /in/V0HgR on line 3
Process exited with code 255.