3v4l.org

run code in 500+ PHP versions simultaneously
<?php $arr = ['foo' => 'bar', 'foobar' => 'barfoo']; foreach ($arr as $key => &$value) { $value = strrev($value); } var_dump($arr);
Output for 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 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 - 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.26, 8.5.0 - 8.5.11
array(2) { ["foo"]=> string(3) "rab" ["foobar"]=> &string(6) "oofrab" }
preferences:
33.87 ms | 1137 KiB | 8 Q