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run code in 500+ PHP versions simultaneously
<?php function my_function($hello = 123) { var_dump($hello); } my_function(null); // > null my_function(undefined); // > 123
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
NULL Fatal error: Uncaught Error: Undefined constant "undefined" in /in/SBibm:9 Stack trace: #0 {main} thrown in /in/SBibm on line 9
Process exited with code 255.
Output for 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
NULL Warning: Use of undefined constant undefined - assumed 'undefined' (this will throw an Error in a future version of PHP) in /in/SBibm on line 9 string(9) "undefined"
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.1 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33
NULL Notice: Use of undefined constant undefined - assumed 'undefined' in /in/SBibm on line 9 string(9) "undefined"
Output for 5.1.0
Fatal error: fatal flex scanner internal error--end of buffer missed in /in/SBibm on line 9
Process exited with code 255.

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