3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = [ 0 => 'apple', 'b' => 'banana', 3 => 'cow', 'wrench' => 'duck', ]; $filtered = array_filter( $array, function ($k) { return is_numeric($k); }, // test to include only numeric keyed ARRAY_FILTER_USE_KEY // new in PHP 5.6 ); var_dump($filtered);
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.24, 8.3.0 - 8.3.12
array(2) { [0]=> string(5) "apple" [3]=> string(3) "cow" }
Output for 5.5.0 - 5.5.38
Notice: Use of undefined constant ARRAY_FILTER_USE_KEY - assumed 'ARRAY_FILTER_USE_KEY' in /in/7KjaV on line 9 Warning: array_filter() expects at most 2 parameters, 3 given in /in/7KjaV on line 9 NULL
preferences:
81.1 ms | 407 KiB | 5 Q