This commit stabilizes `std::borrow`, making the following modifications
to catch up the API with language changes:
* It renames `BorrowFrom` to `Borrow`, as was originally intended (but
blocked for technical reasons), and reorders the parameters
accordingly.
* It moves the type parameter of `ToOwned` to an associated type. This
is somewhat less flexible, in that each borrowed type must have a
unique owned type, but leads to a significant simplification for
`Cow`. Flexibility can be regained by using newtyped slices, which is
advisable for other reasons anyway.
* It removes the owned type parameter from `Cow`, making the type much
less verbose.
* Deprecates the `is_owned` and `is_borrowed` predicates in favor of
direct matching.
The above API changes are relatively minor; the basic functionality
remains the same, and essentially the whole module is now marked
`#[stable]`.
[breaking-change]
This commit is an implementation of [RFC 823][rfc] which is another pass over
the `std::hash` module for stabilization. The contents of the module were not
entirely marked stable, but some portions which remained quite similar to the
previous incarnation are now marked `#[stable]`. Specifically:
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0823-hash-simplification.md
* `std::hash` is now stable (the name)
* `Hash` is now stable
* `Hash::hash` is now stable
* `Hasher` is now stable
* `SipHasher` is now stable
* `SipHasher::new` and `new_with_keys` are now stable
* `Hasher for SipHasher` is now stable
* Many `Hash` implementations are now stable
All other portions of the `hash` module remain `#[unstable]` as they are less
commonly used and were recently redesigned.
This commit is a breaking change due to the modifications to the `std::hash` API
and more details can be found on the [RFC][rfc].
Closes#22467
[breaking-change]
The big change here is that we update the object-safety rules to prohibit references to `Self` in the supertrait listing. See #22040 for the motivation. The other change is to handle the interaction of defaults that reference `Self` and object types (where `Self` is erased). We force users to give an explicit type in that scenario.
r? @aturon
Take 2. This PR includes a bunch of refactoring that was part of an experimental branch implementing [implied bounds]. That particular idea isn't ready to go yet, but the refactoring proved useful for fixing #22246. The implied bounds branch also exposed #22110 so a simple fix for that is included here. I still think some more refactoring would be a good idea here -- in particular I think most of the code in wf.rs is kind of duplicating the logic in implicator and should go, but I decided to post this PR and call it a day before diving into that. I'll write a bit more details about the solutions I adopted in the various bugs. I patched the two issues I was concerned about, which was the handling of supertraits and HRTB (the latter turned out to be fine, so I added a comment explaining why.)
r? @pnkfelix (for now, anyway)
cc @aturon
[implied bounds]: http://smallcultfollowing.com/babysteps/blog/2014/07/06/implied-bounds/
After making `rustc` fail on errors at a stop point, like `-Z parse-only`, in #22117, the files in this PR also fail during the parse stage and should be moved as well. Sorry for spliting this move up in two PRs.
they are used without a feature-gate. This is both kinder to existing
code and should make it easier to land this PR, since we don't
have to catch EVERY SINGLE SUFFIX.
This commit is an implementation of [RFC 823][rfc] which is another pass over
the `std::hash` module for stabilization. The contents of the module were not
entirely marked stable, but some portions which remained quite similar to the
previous incarnation are now marked `#[stable]`. Specifically:
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0823-hash-simplification.md
* `std::hash` is now stable (the name)
* `Hash` is now stable
* `Hash::hash` is now stable
* `Hasher` is now stable
* `SipHasher` is now stable
* `SipHasher::new` and `new_with_keys` are now stable
* `Hasher for SipHasher` is now stable
* Many `Hash` implementations are now stable
All other portions of the `hash` module remain `#[unstable]` as they are less
commonly used and were recently redesigned.
This commit is a breaking change due to the modifications to the `std::hash` API
and more details can be found on the [RFC][rfc].
Closes#22467
[breaking-change]
into variance inference; fix various bugs in variance inference
so that it considers the correct set of constraints; modify infer to
consider the results of variance inference for type arguments.
* Move the type parameter on the `AsciiExt` trait to an associated type named
`Owned`.
* Move `ascii::escape_default` to using an iterator.
This is a breaking change due to the removal of the type parameter on the
`AsciiExt` trait as well as the modifications to the `escape_default` function
to returning an iterator. Manual implementations of `AsciiExt` (or `AsciiExt`
bounds) should be adjusted to remove the type parameter and using the new
`escape_default` should be relatively straightforward.
[breaking-change]
This commit renames the features for the `std::old_io` and `std::old_path`
modules to `old_io` and `old_path` to help facilitate migration to the new APIs.
This is a breaking change as crates which mention the old feature names now need
to be renamed to use the new feature names.
[breaking-change]
Previously an implementation of a stable trait allows implementations of
unstable methods. This updates the stability pass to ensure that all items of an
impl block of a trait are indeed stable on the trait itself.
Pass features along during expansion
Use the set of passed features to detect uses of feature-gated macros without the corresponding feature enabled.
Fix#22234.
----
Also, the framework this add (passing along a reference to the features in the expansion context) is a necessary precursor for landing a properly feature-gated desugaring-based overloaded-`box` and placement-`in` (#22181).
----
This is fixing a bug, but since there might be code out there that is unknowingly taking advantage of that bug, I feel obligated to mark this as a:
[breaking-change]
