protected function determineLoaderFromClass($source): LoaderInterface
    {
        foreach ($this->loaders as $key => $loader) {
            if (class_exists($key) && is_a($source, $key)) {
                return $loader;
            }
        }

        $desc = get_class($source) . ' ' . gettype($source);
        throw new NoLoaderException("Don't know how to load configuration from $desc");
    }