Stabilize `type_alias_enum_variants` in Rust 1.37.0 #61682

Centril · 2019-06-09T05:38:13Z

Stabilize #![feature(type_alias_enum_variants)] which allows type-relative resolution with highest priority to enum variants in both expression and pattern contexts. For example, you may now write:

enum Option<T> {
    None,
    Some(T),
}

type OptAlias<T> = Option<T>;

fn work_on_alias(x: Option<u8>) -> u8 {
    match x {
        OptAlias::Some(y) => y + 1,
        OptAlias::None => 0,
    }
}

Closes rust-lang/rfcs#2218
Closes #52118

r? @petrochenkov

@petrochenkov

type_alias_enum_variants: fix #61801; allow a path pattern to infer Fix #61801. Given a type-relative path pattern referring to an enum variant through a type alias, allow inferring the generic argument applied in the expectation set by the scrutinee of a `match` expression. Similar issues may exist for `let` statements but I don't know how to test for that since `PhantomData<T>` is necessary...) The gist of the problem here was that `resolve_ty_and_res_ufcs` was called twice which is apparently no good... It is possible that this PR is papering over some deeper problem, but that is beyond my knowledge of the compiler. r? @petrochenkov cc @eddyb @alexreg cc #61682 cc #49683

@petrochenkov

type_alias_enum_variants: fix rust-lang#61801; allow a path pattern to infer Fix rust-lang#61801. Given a type-relative path pattern referring to an enum variant through a type alias, allow inferring the generic argument applied in the expectation set by the scrutinee of a `match` expression. Similar issues may exist for `let` statements but I don't know how to test for that since `PhantomData<T>` is necessary...) The gist of the problem here was that `resolve_ty_and_res_ufcs` was called twice which is apparently no good... It is possible that this PR is papering over some deeper problem, but that is beyond my knowledge of the compiler. r? @petrochenkov cc @eddyb @alexreg cc rust-lang#61682 cc rust-lang#49683

@petrochenkov

type_alias_enum_variants: fix rust-lang#61801; allow a path pattern to infer Fix rust-lang#61801. Given a type-relative path pattern referring to an enum variant through a type alias, allow inferring the generic argument applied in the expectation set by the scrutinee of a `match` expression. Similar issues may exist for `let` statements but I don't know how to test for that since `PhantomData<T>` is necessary...) The gist of the problem here was that `resolve_ty_and_res_ufcs` was called twice which is apparently no good... It is possible that this PR is papering over some deeper problem, but that is beyond my knowledge of the compiler. r? @petrochenkov cc @eddyb @alexreg cc rust-lang#61682 cc rust-lang#49683

@petrochenkov

type_alias_enum_variants: fix rust-lang#61801; allow a path pattern to infer Fix rust-lang#61801. Given a type-relative path pattern referring to an enum variant through a type alias, allow inferring the generic argument applied in the expectation set by the scrutinee of a `match` expression. Similar issues may exist for `let` statements but I don't know how to test for that since `PhantomData<T>` is necessary...) The gist of the problem here was that `resolve_ty_and_res_ufcs` was called twice which is apparently no good... It is possible that this PR is papering over some deeper problem, but that is beyond my knowledge of the compiler. r? @petrochenkov cc @eddyb @alexreg cc rust-lang#61682 cc rust-lang#49683

@petrochenkov

type_alias_enum_variants: fix rust-lang#61801; allow a path pattern to infer Fix rust-lang#61801. Given a type-relative path pattern referring to an enum variant through a type alias, allow inferring the generic argument applied in the expectation set by the scrutinee of a `match` expression. Similar issues may exist for `let` statements but I don't know how to test for that since `PhantomData<T>` is necessary...) The gist of the problem here was that `resolve_ty_and_res_ufcs` was called twice which is apparently no good... It is possible that this PR is papering over some deeper problem, but that is beyond my knowledge of the compiler. r? @petrochenkov cc @eddyb @alexreg cc rust-lang#61682 cc rust-lang#49683

@petrochenkov

type_alias_enum_variants: fix #61801; allow a path pattern to infer Fix #61801. Given a type-relative path pattern referring to an enum variant through a type alias, allow inferring the generic argument applied in the expectation set by the scrutinee of a `match` expression. Similar issues may exist for `let` statements but I don't know how to test for that since `PhantomData<T>` is necessary...) The gist of the problem here was that `resolve_ty_and_res_ufcs` was called twice which is apparently no good... It is possible that this PR is papering over some deeper problem, but that is beyond my knowledge of the compiler. r? @petrochenkov cc @eddyb @alexreg cc #61682 cc #49683

bors · 2019-07-01T03:11:27Z

⌛ Testing commit 57e6869 with merge 5748825...

@petrochenkov

…petrochenkov Stabilize `type_alias_enum_variants` in Rust 1.37.0 Stabilize `#![feature(type_alias_enum_variants)]` which allows type-relative resolution with highest priority to `enum` variants in both expression and pattern contexts. For example, you may now write: ```rust enum Option<T> { None, Some(T), } type OptAlias<T> = Option<T>; fn work_on_alias(x: Option<u8>) -> u8 { match x { OptAlias::Some(y) => y + 1, OptAlias::None => 0, } } ``` Closes rust-lang/rfcs#2218 Closes #52118 r? @petrochenkov

bors · 2019-07-01T06:41:42Z

☀️ Test successful - checks-azure, checks-travis, status-appveyor
Approved by: petrochenkov
Pushing 5748825 to master...

Pkgsrc changes: * Add a patch to llvm to deal with const dli_saddr. * Adapt two other patches. * Cross-build currently fails, so i386, powerpc and sparc64 bootstrap kits for 1.37.0 are built natively. Missing aarch64 hardware, so that's not available yet. * Bump bootstrap requirements to 1.36.0 except for armv7-unknown-netbsd-eabihf which I've not managed to cross-build. Upstream changes: Version 1.37.0 (2019-08-15) ========================== Language -------- - `#[must_use]` will now warn if the type is contained in a [tuple][61100], [`Box`][62228], or an [array][62235] and unused. - [You can now use the `cfg` and `cfg_attr` attributes on generic parameters.][61547] - [You can now use enum variants through type alias.][61682] e.g. You can write the following: ```rust type MyOption = Option<u8>; fn increment_or_zero(x: MyOption) -> u8 { match x { MyOption::Some(y) => y + 1, MyOption::None => 0, } } ``` - [You can now use `_` as an identifier for consts.][61347] e.g. You can write `const _: u32 = 5;`. - [You can now use `#[repr(align(X)]` on enums.][61229] - [The `?`/_"Kleene"_ macro operator is now available in the 2015 edition.][60932] Compiler -------- - [You can now enable Profile-Guided Optimization with the `-C profile-generate` and `-C profile-use` flags.][61268] For more information on how to use profile guided optimization, please refer to the [rustc book][rustc-book-pgo]. - [The `rust-lldb` wrapper script should now work again.][61827] Libraries --------- - [`mem::MaybeUninit<T>` is now ABI-compatible with `T`.][61802] Stabilized APIs --------------- - [`BufReader::buffer`] - [`BufWriter::buffer`] - [`Cell::from_mut`] - [`Cell<[T]>::as_slice_of_cells`][`Cell<slice>::as_slice_of_cells`] - [`DoubleEndedIterator::nth_back`] - [`Option::xor`] - [`Wrapping::reverse_bits`] - [`i128::reverse_bits`] - [`i16::reverse_bits`] - [`i32::reverse_bits`] - [`i64::reverse_bits`] - [`i8::reverse_bits`] - [`isize::reverse_bits`] - [`slice::copy_within`] - [`u128::reverse_bits`] - [`u16::reverse_bits`] - [`u32::reverse_bits`] - [`u64::reverse_bits`] - [`u8::reverse_bits`] - [`usize::reverse_bits`] Cargo ----- - [`Cargo.lock` files are now included by default when publishing executable crates with executables.][cargo/7026] - [You can now specify `default-run="foo"` in `[package]` to specify the default executable to use for `cargo run`.][cargo/7056] Misc ---- Compatibility Notes ------------------- - [Using `...` for inclusive range patterns will now warn by default.][61342] Please transition your code to using the `..=` syntax for inclusive ranges instead. - [Using a trait object without the `dyn` will now warn by default.][61203] Please transition your code to use `dyn Trait` for trait objects instead. [62228]: rust-lang/rust#62228 [62235]: rust-lang/rust#62235 [61802]: rust-lang/rust#61802 [61827]: rust-lang/rust#61827 [61547]: rust-lang/rust#61547 [61682]: rust-lang/rust#61682 [61268]: rust-lang/rust#61268 [61342]: rust-lang/rust#61342 [61347]: rust-lang/rust#61347 [61100]: rust-lang/rust#61100 [61203]: rust-lang/rust#61203 [61229]: rust-lang/rust#61229 [60932]: rust-lang/rust#60932 [cargo/7026]: rust-lang/cargo#7026 [cargo/7056]: rust-lang/cargo#7056 [`BufReader::buffer`]: https://doc.rust-lang.org/std/io/struct.BufReader.html#method.buffer [`BufWriter::buffer`]: https://doc.rust-lang.org/std/io/struct.BufWriter.html#method.buffer [`Cell::from_mut`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.from_mut [`Cell<slice>::as_slice_of_cells`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.as_slice_of_cells [`DoubleEndedIterator::nth_back`]: https://doc.rust-lang.org/std/iter/trait.DoubleEndedIterator.html#method.nth_back [`Option::xor`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.xor [`RefCell::try_borrow_unguarded`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.try_borrow_unguarded [`Wrapping::reverse_bits`]: https://doc.rust-lang.org/std/num/struct.Wrapping.html#method.reverse_bits [`i128::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i128.html#method.reverse_bits [`i16::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i16.html#method.reverse_bits [`i32::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i32.html#method.reverse_bits [`i64::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i64.html#method.reverse_bits [`i8::reverse_bits`]: https://doc.rust-lang.org/std/primitive.i8.html#method.reverse_bits [`isize::reverse_bits`]: https://doc.rust-lang.org/std/primitive.isize.html#method.reverse_bits [`slice::copy_within`]: https://doc.rust-lang.org/std/primitive.slice.html#method.copy_within [`u128::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u128.html#method.reverse_bits [`u16::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u16.html#method.reverse_bits [`u32::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u32.html#method.reverse_bits [`u64::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u64.html#method.reverse_bits [`u8::reverse_bits`]: https://doc.rust-lang.org/std/primitive.u8.html#method.reverse_bits [`usize::reverse_bits`]: https://doc.rust-lang.org/std/primitive.usize.html#method.reverse_bits [rustc-book-pgo]: https://doc.rust-lang.org/rustc/profile-guided-optimization.html

Centril added T-lang Relevant to the language team, which will review and decide on the PR/issue. relnotes Marks issues that should be documented in the release notes of the next release. labels Jun 9, 2019

Centril added this to the 1.37 milestone Jun 9, 2019

rust-highfive assigned petrochenkov Jun 9, 2019

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petrochenkov added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jun 9, 2019

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matthewjasper reopened this Jun 9, 2019

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Centril force-pushed the stabilize-type_alias_enum_variants branch from 8e11bda to c2cbbc3 Compare June 10, 2019 04:23

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Centril force-pushed the stabilize-type_alias_enum_variants branch from c2cbbc3 to d75d14a Compare June 12, 2019 21:10

Centril mentioned this pull request Jun 13, 2019

#![feature(type_alias_enum_variants)]: Unit variant pattern through a type alias to generic enum requires type annotations #61801

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richardeoin mentioned this pull request Jun 13, 2019

Doesn't build on stable stm32-rs/stm32h7xx-hal#6

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Centril mentioned this pull request Jun 14, 2019

type_alias_enum_variants: fix #61801; allow a path pattern to infer #61825

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Centril force-pushed the stabilize-type_alias_enum_variants branch from d75d14a to ccdbfda Compare June 14, 2019 21:46

Centril added 6 commits June 15, 2019 18:35

Stabilize type_alias_enum_variants.

ac94bbe

type_alias_enum_variants: Remove feature gate test.

e5060da

Move type_alias_enum_variants tests to a folder; Strip feature gates.

05dc864

type_alias_enum_variants: remove duplicate run-pass test.

0d27995

Cleanup type-alias-enum-variants.rs test.

8642258

Rename type-alias-enum-variants.rs to something descriptive.

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bors added the merged-by-bors This PR was explicitly merged by bors. label Jul 1, 2019

bors merged commit 57e6869 into rust-lang:master Jul 1, 2019

This was referenced Jul 1, 2019

Normalize use of backticks compiler messages #61901

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Use mem::take instead of mem::replace with default #62249

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Centril deleted the stabilize-type_alias_enum_variants branch July 1, 2019 13:33

axic mentioned this pull request Jul 4, 2019

rust: add enum aliases ethereum/evmc#206

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ehuss mentioned this pull request Jul 5, 2019

Document type_alias_enum_variants rust-lang/reference#631

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New lint: Suggest using Self::Variant instead of TheType::Variant rust-lang/rust-clippy#4296

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Tracking issue for RFC 2451, "Re-Rebalancing Coherence" #55437

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burrbull mentioned this pull request Jul 31, 2019

One enum rust-embedded/svd2rust#358

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Centril mentioned this pull request Aug 3, 2019

Stabilize #[doc_alias = "..."] #63236

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Centril mentioned this pull request Aug 18, 2019

Tracking issue for RFC 2565, "Attributes in formal function parameter position" #60406

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Centril mentioned this pull request Aug 26, 2019

Tracking issue for treating tuple struct and variant constructors as const fn #61456

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[Rust] Fixes "common" sub crate using nightly and master apache/tvm#3965

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Won't Compile devashishdxt/cli-table#4

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Set up simple GitHub Actions workflow emgre/win-crypto-ng#3

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Cannot use use Self::*; inside a method #63720

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ci: add travis ci config distil/diffus#99

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제3.2장 Enums 번역합니다. rust-kr/rust-by-example-ko#5

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Namespaced enums are weird in regard to generic paramters #22486

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E0109 is out of date #116876

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Stabilize `type_alias_enum_variants` in Rust 1.37.0 #61682

Stabilize `type_alias_enum_variants` in Rust 1.37.0 #61682

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bors commented Jul 1, 2019

bors commented Jul 1, 2019

Stabilize type_alias_enum_variants in Rust 1.37.0 #61682

Stabilize type_alias_enum_variants in Rust 1.37.0 #61682

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bors commented Jul 1, 2019

bors commented Jul 1, 2019

Stabilize `type_alias_enum_variants` in Rust 1.37.0 #61682

Stabilize `type_alias_enum_variants` in Rust 1.37.0 #61682

Centril commented Jun 9, 2019 •

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