3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = array(1, 2, 3, 4); print_r($a); foreach($a as &$b) { print_r($b); } print_r($a); foreach($a as $b) { } print_r($a);
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 ) 1234Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 ) Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 3 )
preferences:
183.42 ms | 404 KiB | 330 Q