In Chapter 5.9 (References and Borrowing), there is an example [at the very end](https://doc.rust-lang.org/stable/book/references-and-borrowing.html#use-after-free) which shows that declaring a reference before declaring the variable that it points to results in a compilation error. The book does not really mention why this happens though -- in the sections before, it has described how different scopes affects the lifetime of resources, but there is no mention of how resources within the same scope work.
This confused me a little, so I asked on #rust and got the answer that the resources are destroyed in the reverse order that they are declared, but the book makes no mention of it (as far as I can find) -- except in Chapter 5.21 (Drop), where it says:
> When `x` goes out of scope at the end of `main()`, the code for `Drop` will run. `Drop` has one method, which is also called `drop()`. It takes a mutable reference to `self`.
>
> That’s it! The mechanics of `Drop` are very simple, but there are some subtleties. For example, values are dropped in the opposite order they are declared. [...]
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I feel like Chapter 5.9 (References and Borrowing) is probably the best place to put this information (as I have done in my additions), since it deals with other types of referencing and borrowing. However, since English is not my native language, the wording of my additions perhaps are a little "off" -- any feedback on them is appreciated.
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