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run code in 500+ PHP versions simultaneously
<?php function test() { $a = static function () use (&$a) { }; } for ($i = 1; $i <= 20001; $i++) { test(); if ($i == 10000 || $i == 20001) { printf("%d: %f %d\n", $i, memory_get_usage(true), gc_collect_cycles()); } }

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25.43 ms | 476 KiB | 4 Q