public function filter($request): array
    {
        if (\is_array($request)) {
            return $request;
        } elseif ($request === '*') {
            return $this->get();
        } elseif ($request[0] === '!') {
            return \array_diff($this->get(), [\substr($request, 1)]);
        }

        return [$request];
    }