note 130375 added to function.array-intersect-ukey

This is a cleaner and more modern approach (PHP 7.4+ syntax). <?php $array1 = ['blue' => 1, 'red' => 2, 'green' => 3, 'purple' => 4]; $array2 = ['green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8]; $result = array_intersect_ukey($array1, $array2, fn($a, $b) => $a <=> $b); var_dump($result); ?> Explanation: The comparison function fn($a, $b) => $a <=> $b uses the spaceship operator directly inside the array_intersect_ukey call. The result will contain entries from $array1 whose keys also exist in $array2. Output: php Copy Edit array(2) { ["blue"]=> int(1) ["green"]=> int(3) } ---- Server IP: 45.112.84.4 Probable Submitter: 80.90.5.137 (proxied: 103.103.124.167) ---- Manual Page -- https://php.net/manual/en/function.array-intersect-ukey.php Edit -- https://main.php.net/note/edit/130375 Del: integrated -- https://main.php.net/note/delete/130375/integrated Del: useless -- https://main.php.net/note/delete/130375/useless Del: bad code -- https://main.php.net/note/delete/130375/bad+code Del: spam -- https://main.php.net/note/delete/130375/spam Del: non-english -- https://main.php.net/note/delete/130375/non-english Del: in docs -- https://main.php.net/note/delete/130375/in+docs Del: other reasons-- https://main.php.net/note/delete/130375 Reject -- https://main.php.net/note/reject/130375 Search -- https://main.php.net/manage/user-notes.php