protected function _parseTag($string, array $keys = []) {
		$parts = explode(' ', $string, count($keys));
		$result = array_fill_keys($keys, null);

		foreach ($keys as $i => $key) {
			if (isset($parts[$i])) {
				if ($key === 'description') {
					$result[$key] = $this->_clean($parts[$i]);
				} else {
					$result[$key] = $parts[$i];
				}
			}
		}
		return $result;
	}