3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a=[1,2,3,4]; foreach($a as &$v) { echo "$v\n"; array_pop($a);}
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.32, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
1 2
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
1 2 1 1
preferences:
247.6 ms | 402 KiB | 322 Q