Online PHP editor | output for Rt4Jq

<?php $array1 = ["a" => "green", "b" => "brown", "c" => "blue", 0 => "red"]; $array2 = ["a" => "GREEN", "B" => "brown", 0 => "yellow", 1 => "red", "c" => "blue"]; var_export( array_uintersect_assoc( $array1, $array2, function ($a, $b) { //var_export([$a, $b, str_contains($a, $b), (bool)str_contains($a, $b), (int)(bool)str_contains($a, $b)]); //echo "\n"; return str_contains($a, $b); } ) ); echo "\n---\n"; var_export( array_udiff_assoc( $array1, $array2, function ($a, $b) { //var_export([$a, $b, str_contains($a, $b), (bool)str_contains($a, $b), (int)(bool)str_contains($a, $b)]); //echo "\n"; return str_contains($a, $b); } ) ); echo "\n---\n"; var_export( array_uintersect_assoc( $array1, $array2, function ($a, $b) { return str_contains($a, $b) ? 0 : 1; } ) );