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run code in 300+ PHP versions simultaneously
<?php $double = function($a) { return $a * 2; }; var_dump($double);
based on 5Y7uv
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.22, 7.4.0 - 7.4.10, 8.0.0alpha1 - beta3
object(Closure)#1 (1) { ["parameter"]=> array(1) { ["$a"]=> string(10) "<required>" } }