protected static function pack($allowedChildren, $allowedDescendants)
	{
		$allowedChildren    = str_split($allowedChildren,    8);
		$allowedDescendants = str_split($allowedDescendants, 8);

		$allowed = [];
		foreach (array_keys($allowedChildren) as $k)
		{
			$allowed[] = bindec(sprintf(
				'%1$08s%2$08s',
				strrev($allowedDescendants[$k]),
				strrev($allowedChildren[$k])
			));
		}

		return $allowed;
	}