Needed to support:
```rust
match X {
pattern if Y ...
}
for pattern in Y {}
```
IMO, this shouldn't require an RFC because it can't interfere with any future language changes (because `pattern if` and `pattern in` are already legal in rust) and can't cause any ambiguity.
In all other places the IDs of link references are without spaces (and explicitly set).
These are just some cleanups I did for the PDF version.
r? @steveklabnik
A few of us [over on the forum](https://users.rust-lang.org/t/string-type-coercion-in-rust/1439) have been tripped up by this distinction, which I don't think is mentioned. It's kind of logical if you read the "Deref coercions" page and squint a bit but I think it would be nice to explain it directly. Here's one way we could clarify it.
"Truth passes, success `panic!`s" seems to be a typo. The closest fix would be something like "Success passes, failure `panic!`s" but to me a "comparison failure" suggests that we couldn't compare the two values at all, not that we could successfully compare them and that the result was non-equality. So I opted to rewrite the paragraph a bit. If there's a better alternative please let me know.
r? @steveklabnik
The paper from which this example was taken made the mistake of assuming
that all five philosophers are men. This is a hypothetical
example--there are no actual philosophers eating spaghetti--so there is
no good reason to make this assumption. Since women make up about half
of the human population, all things being equal, women should represent
about half of the philosophers. However, because this mistake has stood
since 1985, I have changed *all* of the pronouns to be female, to make
up for lost time. If someone would like to revert this patch or switch
to neutral pronouns after 30 years, feel free to set your alarm clock
for 2045.
This adds strictly more information to the source files and reduces the need for customized tooling to render the book. (While this should not change the output of _rustbook_, it is very useful when rendering the sources with external tools like Pandoc.)
This only adds the language marker to "first level" code blocks (and not to code blocks in comments inside of code examples).
r? @steveklabnik
The source code snippet uses `"whatever".as_bytes()` but the compilation error message uses `b"whatever"`. Both should be consistent with each other.
r? @steveklabnik
Minor tweak: the text explaining the Borrow trait talks about slices, but the example immediately following just uses a simple reference; there are no slices involved.
r? @steveklabnik
