3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $a = 23; $aa = 2233; echo "a${'a'+'b'}b";
based on u5YLU
Output for 7.1.0
Warning: A non-numeric value encountered in /in/svl1D on line 4 Warning: A non-numeric value encountered in /in/svl1D on line 4 Notice: Undefined variable: 0 in /in/svl1D on line 4 ab
Output for 5.0.4 - 7.0.14
Notice: Undefined variable: 0 in /in/svl1D on line 4 ab
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: 0 in /in/svl1D on line 4 ab