3v4l.org

run code in 500+ PHP versions simultaneously
<?php function foo(string $a = NULL) { var_dump($a); } foo(); foo('bar'); foo(NULL);
Output for 8.4.1 - 8.4.24, 8.5.0 - 8.5.9
Deprecated: foo(): Implicitly marking parameter $a as nullable is deprecated, the explicit nullable type must be used instead in /in/VYaKq on line 3 NULL string(3) "bar" NULL
Output for 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 - 8.1.34, 8.2.0 - 8.2.32, 8.3.0 - 8.3.32
NULL string(3) "bar" NULL
preferences:
118.42 ms | 1526 KiB | 4 Q