3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php namespace foo; define (__NAMESPACE__ . '\NULL', 10, false); // produces notice - Constant null already defined echo NULL;
based on iZKoK
Output for 7.0.0 - 7.2.0
Output for 5.3.20 - 5.6.28
10