(PHP 5 >= 5.2.0, PHP 7)
ArrayIterator::uksort — Sort by keys using a user-defined comparison function
) : void
This method sorts the elements by keys using a user-supplied comparison function.
If two members compare as equal, their relative order in the sorted array is undefined.
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
No value is returned.