private function query($string, array $addition) {
		parse_str(parse_url( $string, PHP_URL_QUERY), $queryList);

		foreach ($addition as $key => $value) {
			$queryList[$key] = $value;
		}

		$url = sprintf(
			'%s://%s%s%s',
			parse_url($string, PHP_URL_SCHEME),
			parse_url($string, PHP_URL_HOST),
			parse_url($string, PHP_URL_PATH),
			!empty($queryList) ? '?'.http_build_query($queryList) : ''
		);

		return $url;
	}