3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = [1, 2, 3, 4]; foreach ($a as $k => $v) { echo current($a) . '#' . end($a) . "\n"; echo "{$k}:{$v}\n"; }
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 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#4 0:1 4#4 1:2 4#4 2:3 4#4 3:4
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
2#4 0:1 4#4 1:2 4#4 2:3 4#4 3:4
preferences:
180.79 ms | 402 KiB | 213 Q