Online PHP editor | refs for OgHVv

<?php $array1 = [1, 2, 3]; $array2 = [4, 5, 6]; function udiffCompare($a, $b) { echo "Compare $a and $b\n"; } var_export( array_udiff($array1, $array2, 'udiffCompare') ); echo "\n---\n"; function udiffCompare2($a, $b) { echo "Compare $a and $b\n"; return $a <=> $b; } var_export( array_udiff($array1, $array2, 'udiffCompare2') );