public static function filterValuesRecursively(array $array, Closure $callback = null)
    {
        foreach ($array as $index => $value) {
            if (is_array($value)) {
                $array[$index] = call_user_func(__METHOD__, $value, $callback);
            } else {
                $array[$index] = call_user_func($callback, $value);
            }
        }

        return $array;
    }