The function cmp itself doesn’t do the sorting. It just tells usort if a value is smaller, equal or greater than another value. E.g. if $a = 5 and $b = 9 it will return 1 to indicate that the value in $b is greater than the one in $a. Sorting is done by usort.
How does the comparator work? I’m not sure wether this was part of the question, but to be clear about how the comparator works: You have an order specified by ordered list $order and a special comparator callback list_cmp which (should) return wether argument $a is smaller than $b (return -1 or a value < … Read more
I think this question deserves an update. I know the original question was for PHP version 5.2, but I came here looking for a solution and found one for newer versions of PHP and thought this might be useful for other people as well. For PHP 5.3 and up, you can use the ‘use‘ keyword … Read more
Personally, I would use a custom (anonymous) function in conjunction with usort(). EDIT: Re – your comment. Hopefully this will put you on the right track. This function gives equal priority to elements which both have EN or neither have EN, or adjusted priority when just one has EN. usort($array,function ($a, $b) { $ac = … Read more