3v4l.org

run code in 300+ PHP versions simultaneously
<?php declare(strict_types=1); error_reporting(E_ALL); ini_set("display_errors", "1"); $a =[ null=>"null key?" ]; var_dump($a);
Output for 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
array(1) { [""]=> string(9) "null key?" }
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Warning: Unsupported declare 'strict_types' in /in/Eu0L3 on line 2 array(1) { [""]=> string(9) "null key?" }
Output for 5.3.0 - 5.3.29
Warning: Unsupported declare 'strict_types' in /in/Eu0L3 on line 2 Parse error: syntax error, unexpected '[' in /in/Eu0L3 on line 6
Process exited with code 255.
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected '[' in /in/Eu0L3 on line 6
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/Eu0L3 on line 6
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/Eu0L3 on line 6
Process exited with code 255.

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