3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = ['green', '', 'red', '', 'blue', '', 'yellow', '', 'purple', '', 'white', '', 'black']; usort($array, fn($a, $b) => !$a <=> !$b); var_export($array);
Output for 8.1.32 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array ( 0 => 'green', 1 => 'red', 2 => 'blue', 3 => 'yellow', 4 => 'purple', 5 => 'white', 6 => 'black', 7 => '', 8 => '', 9 => '', 10 => '', 11 => '', 12 => '', )

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