New question about cloning references

[peterjoel]

My original idea was a bit more complicated: https://gist.github.com/peterjoel/8975ab7ff3211d72d3704c948d21a0b0

The more tricky part of that (B is actually a fn, which is Clone and has zero size) can be a separate question.

[dtolnay]

Thanks! This is a terrific question.

[dtolnay]

Published to https://dtolnay.github.io/rust-quiz/30.
(You may need to refresh https://dtolnay.github.io/rust-quiz/questions.js before you can see it.)

I made some changes to the explanation in 86b825f. Basically I found it clearer to focus on what type parameter the generic function is instantiated with, and present the answer in terms of X = &A, X = () etc.

To facilitate that, I renamed the type parameter from T to X so that it doesn't get mixed it up when talking about references &T and Rc<T> in general where the symbol T does not refer specifically to the type parameter of our specific function in the quiz code.

I filled in some relevant detail as well:

• Why does b.clone() not call the impl for &()?

• Why does impl Clone for &T exist if it is so confusing?