3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array(0,null,3,null); $filtered = array_filter($arr, is_null); print_r($filtered);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Fatal error: Uncaught Error: Undefined constant "is_null" in /in/XiVsv:4 Stack trace: #0 {main} thrown in /in/XiVsv on line 4
Process exited with code 255.
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Use of undefined constant is_null - assumed 'is_null' (this will throw an Error in a future version of PHP) in /in/XiVsv on line 4 Array ( [1] => [3] => )
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33
Notice: Use of undefined constant is_null - assumed 'is_null' in /in/XiVsv on line 4 Array ( [1] => [3] => )

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