3v4l.org

run code in 300+ PHP versions simultaneously
<?php $list = ['A', 'B', 'C', 'D']; echo current($list) . "\n"; echo next($list) . "\n"; echo prev($list);
Output for 7.1.26 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.25, 8.0.0 - 8.0.12, 8.1rc1 - rc3
A B A

preferences:
40.85 ms | 460 KiB | 5 Q