public function registerPath($namespace, $path, $prepend = false)
    {
        $namespace = Normalizer::ns($namespace, true);
        $index     = substr($namespace, 0, 4);

        $this->indexes[$index] = true;

        $path = Normalizer::path($path, true);

        if (! isset($this->paths[$namespace])) {
            $this->paths[$namespace] = [];
        }
        if ($prepend) {
            array_unshift($this->paths[$namespace], $path);

            return $this;
        }
        array_push($this->paths[$namespace], $path);

        return $this;
    }