private function parseUrl( $url = '', Array $query_string_vars = [ ] ) {
        parse_str( parse_url( $url, PHP_URL_QUERY ), $this->query_string );
        $request_uri = trim( parse_url( $url, PHP_URL_PATH ), '/' );
        $this->request = trim( preg_replace( '#^/*index\.php#', '', $request_uri ), '/' );
        if ( ! empty( $query_string_vars ) ) {
            $this->query_string = array_merge( $this->query_string, $query_string_vars );
        }
    }