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run code in 300+ PHP versions simultaneously
<?php define("NULL", true, true); if (NULL === null) { echo "null"; } else { echo "huh?"; }
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
Warning: define(): Argument #3 ($case_insensitive) is ignored since declaration of case-insensitive constants is no longer supported in /in/2Ip0Q on line 3 Warning: Constant NULL already defined in /in/2Ip0Q on line 3 null
Output for 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Deprecated: define(): Declaration of case-insensitive constants is deprecated in /in/2Ip0Q on line 3 Notice: Constant null already defined in /in/2Ip0Q on line 3 null
Output for 7.3.32 - 7.3.33
null
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 - 5.5.36, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.6 - 7.2.33
Notice: Constant null already defined in /in/2Ip0Q on line 3 null

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