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run code in 300+ PHP versions simultaneously
<?php $a = function() { return function() { echo __FUNCTION__; }; }; $a()();
based on PXt64
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.25, 7.2.0 - 7.2.31, 7.3.0 - 7.3.19, 7.4.0 - 7.4.8, 8.0.0alpha1 - alpha2
{closure}
Output for 5.6.38
Parse error: syntax error, unexpected '(' in /in/27QQ7 on line 8
Process exited with code 255.