This rewrites them to the current `ItemStatic` production of the compiler, but I
want to get this into a snapshot. It will be illegal to use a `static` in a
pattern of a `match` statement, so all those current uses will need to be
rewritten to `const` once it's implemented. This requires that the stage0
snapshot is able to parse `const`.
cc #17718
prefer `Deref` over `DerefMut` in all other circumstances.
Because the compiler now prefers `Deref`, this can break code that
looked like:
let mut foo = bar.borrow_mut();
(*foo).call_something_that_requires_mutable_self();
Replace this code with:
let mut foo = bar.baz();
(&mut *foo).call_something_that_requires_mutable_self();
Closes#12825.
[breaking-change]
r? @nikomatsakis
Modify ast::ExprMatch to include a new value of type ast::MatchSource,
making it easy to tell whether the match was written literally or
produced via desugaring. This allows us to customize error messages
appropriately.
This makes it easier to experiment with improved quasiquoting as an ordinary
plugin library.
The list of quote macros in feature_gate.rs was already out of sync;
this commit also prevents that problem in the future.
in favor of `move`.
This breaks code that used `move` as an identifier, because it is now a
keyword. Change such identifiers to not use the keyword `move`.
Additionally, this breaks code that was counting on by-value or
by-reference capture semantics for unboxed closures (behind the feature
gate). Change `ref |:|` to `|:|` and `|:|` to `move |:|`.
Part of RFC #63; part of issue #12831.
[breaking-change]
Deprecates the `find_or_*` family of "internal mutation" methods on `HashMap` in
favour of the "external mutation" Entry API as part of RFC 60. Part of #17320,
but this still needs to be done on the rest of the maps. However they don't have
any internal mutation methods defined, so they can be done without deprecating
or breaking anything. Work on `BTree` is part of the complete rewrite in #17334.
The implemented API deviates from the API described in the RFC in two key places:
* `VacantEntry.set` yields a mutable reference to the inserted element to avoid code
duplication where complex logic needs to be done *regardless* of whether the entry
was vacant or not.
* `OccupiedEntry.into_mut` was added so that it is possible to return a reference
into the map beyond the lifetime of the Entry itself, providing functional parity
to `VacantEntry.set`.
This allows the full find_or_insert functionality to be implemented using this API.
A PR will be submitted to the RFC to amend this.
[breaking-change]
This extends cfg-gating to attributes.
```rust
#[cfg_attr(<cfg pattern>, <attr>)]
```
will expand to
```rust
#[<attr>]
```
if the `<cfg pattern>` matches the current cfg environment, and nothing
if it does not. The grammar for the cfg pattern has a simple
recursive structure:
* `value` and `key = "value"` are cfg patterns,
* `not(<cfg pattern>)` is a cfg pattern and matches if `<cfg pattern>`
does not.
* `all(<cfg pattern>, ...)` is a cfg pattern and matches if all of the
`<cfg pattern>`s do.
* `any(<cfg pattern>, ...)` is a cfg pattern and matches if any of the
`<cfg pattern>`s do.
Examples:
```rust
// only derive Show for assert_eq! in tests
#[cfg_attr(test, deriving(Show))]
struct Foo { ... }
// only derive Show for assert_eq! in tests and debug builds
#[cfg_attr(any(test, not(ndebug)), deriving(Show))]
struct Foo { ... }
// ignore a test in certain cases
#[test]
#[cfg_attr(all(not(target_os = "linux"), target_endian = "big"), ignore)]
fn test_broken_thing() { ... }
// Avoid duplication when fixing staging issues in rustc
#[cfg_attr(not(stage0), lang="iter")]
pub trait Iterator<T> { ... }
```
Because I'm still 😷😷😷 , I figured some mindless tasks would be better than trying to finish the ownership guide.
The manual has long been waiting for some ❤️❤️❤️ , and so I gave it a quick once-over. I made small commits in case any of the changes are a bit weird, I mostly did a few things:
1. changed 'manual' to 'reference.' I feel like this name is better. If it's not, It's not a huge deal. it shouldn't be `rust.md` though.
2. word wrapped everything appropriately. Changes 1&2 are in the first commit, so that its' easier to see the changes in the later ones.
3. fixed other small style issues
4. removed references to things that are in the standard library, and not the language itself
There's still lots of gross in here, but I didn't want to pile on too too many changes.
/cc @brson @nikomatsakis
