Online PHP editor | refs for EPA6I

<?php $array = ['green', '', 'red', '', 'blue', '', 'yellow', '', 'purple', '', 'white', '', 'black']; usort($array, function($a) { static $i = 0; var_dump($a, ++$i); return (int)!$a;} ); var_export($array); echo "\n---\n"; $array = ['green', '', 'red', '', 'blue', '', 'yellow', '', 'purple', '', 'white', '', 'black']; usort($array, function($a, $b) { static $i = 0; var_dump($a, ++$i); return !$a <=> !$b;} ); var_export($array);