OK, so you can't copy a reference to a type whose class is totally unknown at compile time.

因此，不能复制在编译时根本不知道是什么类的类型引用。

youdao

To her the outside world was a totally unknown quantity.

对她来说，外部世界完全是个未知数。

youdao

Their origins are beyond our knowledge and their future destinations are totally unknown.

我们无从了解他们的出身，也全然不知其未来的归宿何在。

youdao

Unlike his younger, media-obsessed brother, Teddy is almost totally unknown to the wider public.

ECONOMIST: The environment

Mr. Bush: The biggest obstacle to athena's business success has been the fact that we're totally unknown.

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That can help the Huffington Post, which is totally unknown in France, to build its brand faster than expected.

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