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run code in 300+ PHP versions simultaneously
<?php $b = 123; $a = array('' => &$b, 'b' => 1, 'd' => 4, 'c' => 3); uasort($a, function($a, $b) { if ($a == $b) { return 0; } return ($a < $b) ? -1 : 1; }); var_dump($a);

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57.34 ms | 402 KiB | 5 Q