3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = ['cat', 'dog', 'horse']; foreach($array as &$a) {} foreach($array as $a) { echo $a . "\n"; }
Output for 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
cat dog dog
preferences:
103.72 ms | 1938 KiB | 4 Q