3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array(2, 4, 8); doFoo($arr); echo '<pre>'; print_r($arr); function doFoo($array) { foreach ($array as &$foo) { $foo += 1; echo '<pre>' . $foo . '</pre>'; } }

preferences:
38.42 ms | 402 KiB | 5 Q