3v4l.org

run code in 500+ PHP versions simultaneously
<?php $a = 1; $f1 = fn() => $a = 2; $b = &$a; $f2 = fn() => $b = 3; echo $f1(); echo $a; echo PHP_EOL; echo $f2(); echo $a; echo PHP_EOL;
Output for 8.1.34, 8.2.0 - 8.2.31, 8.3.0 - 8.3.31, 8.4.1 - 8.4.22, 8.5.0 - 8.5.7
21 31
preferences:
62.95 ms | 861 KiB | 4 Q