3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = ['a' => '123', 'b' => '321', 'c' => ['asdf' => 'asdf']]; $b = ['a' => '123', 'b' => '123', 'c' => ['asdf' => 'asdf123']]; $r = array_udiff_assoc($a, $b, function($old, $new) { var_dump($old, $new); return $new == $old ? 0 : -1; }); var_dump($r);
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
string(3) "123" string(3) "123" string(3) "321" string(3) "123" array(1) { ["asdf"]=> string(4) "asdf" } array(1) { ["asdf"]=> string(7) "asdf123" } array(2) { ["b"]=> string(3) "321" ["c"]=> array(1) { ["asdf"]=> string(4) "asdf" } }

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228.12 ms | 405 KiB | 268 Q