3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php echo "${3+1}";
based on Aq0K3
Output for 5.0.4 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
Notice: Undefined variable: 4 in /in/n6fDU on line 2
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: 4 in /in/n6fDU on line 2