note 97932 added to function.uasort

Note that your sort function should *never* return a value of 0 because it will still cause two items of 'equal' value to be swapped. Using the cmp() function in the documentation with two keys that have the same values: <?php // Comparison function function cmp($a, $b) { if ($a == $b) { return 0; } return ($a < $b) ? -1 : 1; } // Array to be sorted $array = array('a' => 4, 'b' => 8, 'c' => -1, 'd' => -1); print_r($array); // Sort and print the resulting array uasort($array, 'cmp'); print_r($array); ?> Results in the elements with keys 'c' and 'd' being swapped around: <?php Array ( [a] => 4 [b] => 8 [c] => -1 [d] => -1 ) Array ( [d] => -1 [c] => -1 [a] => 4 [b] => 8 ) ?> If you remove the return '0' condition in cmp(), you get what everyone would expect, that 'c' and 'd' have not been swapped. <?php Array ( [a] => 4 [b] => 8 [c] => -1 [d] => -1 ) Array ( [c] => -1 [d] => -1 [a] => 4 [b] => 8 ) ?> ---- Server IP: 69.147.83.197 Probable Submitter: 98.161.6.254 ---- Manual Page -- http://www.php.net/manual/en/function.uasort.php Edit -- https://master.php.net/note/edit/97932 Del: integrated -- https://master.php.net/note/delete/97932/integrated Del: useless -- https://master.php.net/note/delete/97932/useless Del: bad code -- https://master.php.net/note/delete/97932/bad+code Del: spam -- https://master.php.net/note/delete/97932/spam Del: non-english -- https://master.php.net/note/delete/97932/non-english Del: in docs -- https://master.php.net/note/delete/97932/in+docs Del: other reasons-- https://master.php.net/note/delete/97932 Reject -- https://master.php.net/note/reject/97932 Search -- https://master.php.net/manage/user-notes.php