3v4l.org

run code in 500+ PHP versions simultaneously
<?php function foo($a) {} // 2 * undefined variable foo($b); var_dump($b); // NULL // no error function foo2(&$a) {} // undefined variable foo($c); // Now, $c exists var_dump($c); // NULL
Output for 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.26, 8.5.0 - 8.5.11
Warning: Undefined variable $b in /in/fKV5D on line 5 Warning: Undefined variable $b in /in/fKV5D on line 6 NULL Warning: Undefined variable $c in /in/fKV5D on line 11 Warning: Undefined variable $c in /in/fKV5D on line 13 NULL
preferences:
29.22 ms | 1152 KiB | 7 Q