PHP Array Reverse by array_walk() (Without Loops)

I’ve procrastinated writing the following function over 11 years. It is simple, though; I have a back story about it. Thanks to that, I have been hanging onto it although it’s so simple. This will load off my mind. It’s better late than 11 year sorry.

$arr_str = ['a', 'b', 'c', 'd'];
$arr_rev = [];
$arr_len = count($arr_str);
array_walk($arr_str, function($item, $key) use (&$arr_rev, &$arr_len) {
  $arr_rev[--$arr_len] = $item;
});
ksort($arr_rev);