3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array('a' => false, 'b' => null, 'c' => '', 'd' => 'd'); foreach ($array as $k => $v) { printf( '%s => %s isset = %s ake = %s', $k, $v, isset($array[ $k ]), array_key_exists($k, $array) ); }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 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
a => isset = 1 ake = 1b => isset = ake = 1c => isset = 1 ake = 1d => d isset = 1 ake = 1
preferences:
240.45 ms | 406 KiB | 354 Q