3v4l.org

run code in 300+ PHP versions simultaneously
<?php function foo(?int $bar) { } foo(1); foo(null);
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.32, 8.2.0 - 8.2.28, 8.3.0 - 8.3.22, 8.4.1 - 8.4.8
preferences:
97.53 ms | 409 KiB | 5 Q