Tests if this hashtable maps no keys to values.

测试哈希表是否有key到值的映射。

youdao

But the problem with cars, as often with people, is that what truly matters lies beneath the surface, and since there were no keys available for any of the autos, their innards had to remain untested.

可是汽车的问题，常常同人一样，真正重要的部分不在表面。既然所有的车都没钥匙，内部情况便无从考验。

youdao

But the problem with cars, as often with people, is that what truly matters lies beneath the surface, and since there were no keys available for any of the autos, their innards had to remain untested.

可是汽车的问题，常常同人一样，真正重要的部分不在表面。既然所有的车都没钥匙，内部情况便无从考验。

youdao