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run code in 300+ PHP versions simultaneously
<?php function closure() { $a = 0; return function () use (&$a) { return $a++; }; } $c = closure(); var_dump($c()); var_dump($c()); var_dump($c()); var_dump($c()); var_dump($c()); var_dump(function () { return $c; });
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
int(0) int(1) int(2) int(3) int(4) object(Closure)#2 (0) { }

preferences:
145.21 ms | 404 KiB | 174 Q