note 107928 added to function.array-diff

There is more fast implementation of array_diff, but with some limitations. If you need compare two arrays of integers or strings you can use such function: public static function arrayDiffEmulation($arrayFrom, $arrayAgainst) { $arrayAgainst = array_flip($arrayAgainst); foreach ($arrayFrom as $key => $value) { if(isset($arrayAgainst[$value])) { unset($arrayFrom[$key]); } } return $arrayFrom; } It is ~10x faster than array_diff php > $t = microtime(true);$a = range(0,25000); $b = range(15000,500000); $c = array_diff($a, $b);echo microtime(true) - $t; 4.4335179328918 php > $t = microtime(true);$a = range(0,25000); $b = range(15000,500000); $c = arrayDiffEmulation($a, $b);echo microtime(true) - $t; 0.37219095230103 ---- Server IP: 69.147.83.197 Probable Submitter: 89.209.68.106 ---- Manual Page -- http://www.php.net/manual/en/function.array-diff.php Edit -- https://master.php.net/note/edit/107928 Del: integrated -- https://master.php.net/note/delete/107928/integrated Del: useless -- https://master.php.net/note/delete/107928/useless Del: bad code -- https://master.php.net/note/delete/107928/bad+code Del: spam -- https://master.php.net/note/delete/107928/spam Del: non-english -- https://master.php.net/note/delete/107928/non-english Del: in docs -- https://master.php.net/note/delete/107928/in+docs Del: other reasons-- https://master.php.net/note/delete/107928 Reject -- https://master.php.net/note/reject/107928 Search -- https://master.php.net/manage/user-notes.php