3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $a = "b"; $b = 1; echo $a; echo $$a; ?>
based on KOCag
Output for 4.3.0 - 5.6.28, hhvm-3.12.0, 7.0.0 - 7.1.0
b1
Output for hhvm-3.10.0

Process exited with code 153.