3v4l.org

run code in 300+ PHP versions simultaneously
<?php class T { public function __construct($v) { $this->v = $v; } public function __toString() { return 'a'; } } $list = [new T(1), new T(2)]; usort($list, function($a, $b) { return strcmp($a, $b); }); // PHP reverses $list but HHVM doesn't touch it print_r($list);

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45.09 ms | 402 KiB | 5 Q