3v4l.org

run code in 300+ PHP versions simultaneously
<?php $entry = array( 0 => 'foo', 1 => false, 2 => -1, 3 => null, 4 => '' ); var_dump(array_filter($entry)); var_dump(array_filter($entry), 'isset');
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, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array(2) { [0]=> string(3) "foo" [2]=> int(-1) } array(2) { [0]=> string(3) "foo" [2]=> int(-1) } string(5) "isset"

preferences:
257.02 ms | 406 KiB | 338 Q