Tracking issue for RFC 2229, "Closures Capture Disjoint Fields" #53488

Centril · 2018-08-19T08:56:56Z

This is a tracking issue for the RFC "Closures Capture Disjoint Fields" (rust-lang/rfcs#2229).

Status

This is under active development by the wg-rfc-2229 compiler-team working group. You can track their progress on the project-rfc-2229 repository.

Implementation plan and status

See the RFC 2229 project board and milestones.

Links, see also

RFC 2229 implementation plan compiler-team#292, a Major Change Proposal outlining an initial plan

Unresolved questions:

How to optimize pointers. Can borrows that all reference parts of the same object be stored as a single pointer? How should this optimization be implemented (e.g. a special repr, refinement typing)?
How to signal that a function is pure. Is this even needed/wanted? Any other places where the language could benefit?
Should Box be special?
Drop order can change as a result of this RFC, is this a real stability problem? How should this be resolved?

This issue has been assigned to @arora-aman via this comment.

The text was updated successfully, but these errors were encountered:

eddyb · 2018-08-19T10:02:00Z

IIRC, this needs to wait for the new MIR (NLL) borrow-checker to replace the old one.
cc @rust-lang/wg-compiler-nll

samsartor · 2018-08-21T06:11:07Z

I would love to follow this through and give the code a shot, but it's probably too big of a first contribution to the compiler. Maybe I'll take a swing at some starter issues and then come back if no one else has gotten it done.

@eddyb Yes, this definitely should be built on NLL.

rust-lang#53488 Refactoring UpvarId

@ghost

Rollup of 25 pull requests Successful merges: - #55562 (Add powerpc- and powerpc64-unknown-linux-musl targets) - #55564 (test/linkage-visibility: Ignore on musl targets) - #55827 (A few tweaks to iterations/collecting) - #55834 (Forward the ABI of the non-zero sized fields of an union if they have the same ABI) - #55857 (remove unused dependency) - #55862 (in which the E0618 "expected function" diagnostic gets a makeover) - #55867 (do not panic just because cargo failed) - #55894 (miri enum discriminant handling: Fix treatment of pointers, better error when it is undef) - #55916 (Make miri value visitor usfeful for mutation) - #55919 (core/tests/num: Simplify `test_int_from_str_overflow()` test code) - #55923 (reword #[test] attribute error on fn items) - #55935 (appveyor: Use VS2017 for all our images) - #55949 (ty: return impl Iterator from Predicate::walk_tys) - #55952 (Update to Clang 7 on CI.) - #55953 (#53488 Refactoring UpvarId) - #55962 (rustdoc: properly calculate spans for intra-doc link resolution errors) - #55963 (Stress test for MPSC) - #55968 (Clean up some non-mod-rs stuff.) - #55970 (Miri backtrace improvements) - #56007 (CTFE: dynamically make sure we do not call non-const-fn) - #56011 (Replace data.clone() by Arc::clone(&data) in mutex doc.) - #56012 (avoid shared ref in UnsafeCell::get) - #56016 (Add VecDeque::resize_with) - #56027 (docs: Add missing backtick in object_safety.rs docs) - #56043 (remove "approx env bounds" if we already know from trait) Failed merges: r? @ghost

rust-lang#53488 Refactoring UpvarId

Rollup of 25 pull requests Successful merges: - #55562 (Add powerpc- and powerpc64-unknown-linux-musl targets) - #55564 (test/linkage-visibility: Ignore on musl targets) - #55827 (A few tweaks to iterations/collecting) - #55834 (Forward the ABI of the non-zero sized fields of an union if they have the same ABI) - #55857 (remove unused dependency) - #55862 (in which the E0618 "expected function" diagnostic gets a makeover) - #55867 (do not panic just because cargo failed) - #55894 (miri enum discriminant handling: Fix treatment of pointers, better error when it is undef) - #55916 (Make miri value visitor useful for mutation) - #55919 (core/tests/num: Simplify `test_int_from_str_overflow()` test code) - #55923 (reword #[test] attribute error on fn items) - #55949 (ty: return impl Iterator from Predicate::walk_tys) - #55952 (Update to Clang 7 on CI.) - #55953 (#53488 Refactoring UpvarId) - #55962 (rustdoc: properly calculate spans for intra-doc link resolution errors) - #55963 (Stress test for MPSC) - #55968 (Clean up some non-mod-rs stuff.) - #55970 (Miri backtrace improvements) - #56007 (CTFE: dynamically make sure we do not call non-const-fn) - #56011 (Replace data.clone() by Arc::clone(&data) in mutex doc.) - #56012 (avoid shared ref in UnsafeCell::get) - #56016 (Add VecDeque::resize_with) - #56027 (docs: Add missing backtick in object_safety.rs docs) - #56043 (remove "approx env bounds" if we already know from trait) - #56059 (Increase `Duration` approximate equal threshold to 1us)

ghedo · 2019-09-05T15:42:01Z

@blitzerr could you please provide a status update on this? it looks like the related issues (#57482 and #60205) had some work done, but they look stuck now. Anything that needs help with? Not sure if I can do anything, but I can try :)

tesuji · 2020-05-15T13:49:50Z

I know. But with polonius, there might be support for self-referential types in the future. So for future design space we need to care about how to interact this feature with self-referential types.

Ixrec · 2020-05-16T22:08:45Z

This is the first I've heard of Polonius having anything to do with self-referential types, despite having read all the blog posts and docs behind your link. Is this interaction spelled out somewhere?

KiChjang · 2020-05-16T22:18:03Z

@Ixrec I do recall that there was a presentation from Niko that says it could maybe help with self-referential structs somehow, but he did preface it by saying that it's purely speculative: https://youtu.be/_agDeiWek8w?t=1900.

nikomatsakis · 2020-05-21T23:29:07Z

I'm not really aware of any particular interaction between this feature and self-referential types. Am I missing something?

nikomatsakis · 2020-06-08T18:32:16Z

@rustbot assign arora-aman

rustbot · 2020-06-08T18:32:17Z

Error: Parsing assign command in comment failed: ...'arora-aman' | error: user should start with @ at >| ''...

Please let @rust-lang/release know if you're having trouble with this bot.

varkor · 2020-06-09T01:22:52Z

@rustbot assign @arora-aman

arora-aman · 2020-06-22T02:12:53Z

@rustbot claim

@nikomatsakis

…matsakis rustc_typeck: construct {Closure,Generator}Substs more directly. We've previously not had a way to create `{Closure,Generator}Substs` other than instantiating all generics as inference variables and unifying the inference types (extracted using the regular `{Closure,Generator}Substs` accessors), with the actual types. With this PR, those hacks, and assumptions about the order of closure/generator-specific components, are replaced with a simple API where the base `Substs` are combined with the additional information into a `{Closure,Generator}Substs`. This might also be faster than relying inference, although probably not by much. r? @nikomatsakis cc rust-lang#53488 @blitzerr

@nikomatsakis

…matsakis rustc_typeck: construct {Closure,Generator}Substs more directly. We've previously not had a way to create `{Closure,Generator}Substs` other than instantiating all generics as inference variables and unifying the inference types (extracted using the regular `{Closure,Generator}Substs` accessors), with the actual types. With this PR, those hacks, and assumptions about the order of closure/generator-specific components, are replaced with a simple API where the base `Substs` are combined with the additional information into a `{Closure,Generator}Substs`. This might also be faster than relying inference, although probably not by much. r? @nikomatsakis cc rust-lang#53488 @blitzerr

taikulawo · 2021-06-21T04:55:56Z

any update on this? Does the RFC has been implemented in rust?

arora-aman · 2021-06-21T06:07:13Z

any update on this? Does the RFC has been implemented in rust?

Yes it's available on the Rust nightly builds under #![feature(capture_disjoint_fields)].

On a somewhat side note we should probably update the tracking issue with the project board.

taikulawo · 2021-06-21T06:23:45Z

any update on this? Does the RFC has been implemented in rust?

Yes it's available on the Rust nightly builds under #![feature(capture_disjoint_fields)].

On a somewhat side note we should probably update the tracking issue with the project board.

Yes, please, RFC tracking issue should reveal whether it has been implemented, and how to use it 😃. I believe that someone have same concerns with me

nikomatsakis · 2021-08-17T23:27:46Z

Stabilization proposed in #88126

ehuss · 2021-10-02T14:52:43Z

Since this is now stabilized, should this issue be closed?

nikomatsakis · 2021-10-05T00:20:33Z

Yes.

Centril added B-RFC-approved Feature: Approved by a merged RFC but not yet implemented. T-lang Relevant to the language team, which will review and decide on the PR/issue. C-tracking-issue Category: A tracking issue for an RFC or an unstable feature. labels Aug 19, 2018

Centril mentioned this issue Aug 19, 2018

Closures Capture Disjoint Fields rust-lang/rfcs#2229

Merged

blitzerr self-assigned this Oct 29, 2018

pietroalbini mentioned this issue Nov 15, 2018

Rollup of 15 pull requests #55990

Closed

pietroalbini added a commit to pietroalbini/rust that referenced this issue Nov 16, 2018

Rollup merge of rust-lang#55953 - blitzerr:master, r=nikomatsakis

357031a

rust-lang#53488 Refactoring UpvarId

kennytm added a commit to kennytm/rust that referenced this issue Nov 17, 2018

Rollup merge of rust-lang#55953 - blitzerr:master, r=nikomatsakis

1a662d2

rust-lang#53488 Refactoring UpvarId

kennytm mentioned this issue Nov 17, 2018

Rollup of 17 pull requests #56026

Closed

pietroalbini added a commit to pietroalbini/rust that referenced this issue Nov 18, 2018

Rollup merge of rust-lang#55953 - blitzerr:master, r=nikomatsakis

7869aeb

rust-lang#53488 Refactoring UpvarId

pietroalbini mentioned this issue Nov 18, 2018

Rollup of 25 pull requests #56051

Merged

kennytm pushed a commit to pietroalbini/rust that referenced this issue Nov 19, 2018

Rollup merge of rust-lang#55953 - blitzerr:master, r=nikomatsakis

989d06a

rust-lang#53488 Refactoring UpvarId

jonas-schievink mentioned this issue Jan 10, 2019

Polonius borrow checker regression in recent nightlies #57487

Closed

blitzerr mentioned this issue Jan 12, 2019

Add a map in the TypeckTables to get all Upvars given the a closure ID #56905

Closed

oleganza mentioned this issue Mar 19, 2019

MuSig: add counterparties stellar/slingshot#229

Merged

3 tasks

nikomatsakis mentioned this issue Apr 23, 2019

refactor uses of freevars to use the upvar list #60205

Closed

This was referenced May 19, 2020

Simplify executor by merging task_queue and wake_queue phil-opp/blog_os#804

Merged

Comments for "https://os.phil-opp.com/async-await/" phil-opp/blog_os#768

Closed

fmckeogh mentioned this issue May 27, 2020

Parallel sections can be improved once RFC 2229 is resolved rse-standrewscs/shallow-water#36

Open

nikomatsakis unassigned blitzerr Jun 8, 2020

rustbot self-assigned this Jun 9, 2020

rustbot assigned rustbot and unassigned rustbot Jun 22, 2020

eddyb mentioned this issue Jul 14, 2020

rustc_typeck: construct {Closure,Generator}Substs more directly. #74314

Merged

nikomatsakis added this to Proposed in 2021 Edition Blockers Jul 30, 2020

jonas-schievink mentioned this issue Aug 22, 2020

Add Iterator::intersperse #75784

Closed

Aaron1011 mentioned this issue Aug 26, 2020

Point to a move-related span when pointing to closure upvars #75933

Merged

nikomatsakis mentioned this issue Aug 17, 2021

stabilize disjoint capture in closures (RFC 2229) #88126

Closed

2 tasks

nikomatsakis closed this as completed Oct 5, 2021

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Tracking issue for RFC 2229, "Closures Capture Disjoint Fields" #53488

Tracking issue for RFC 2229, "Closures Capture Disjoint Fields" #53488

Centril commented Aug 19, 2018 •

edited by nikomatsakis

eddyb commented Aug 19, 2018

samsartor commented Aug 21, 2018

ghedo commented Sep 5, 2019

tesuji commented May 15, 2020 •

edited

Ixrec commented May 16, 2020

KiChjang commented May 16, 2020

nikomatsakis commented May 21, 2020

nikomatsakis commented Jun 8, 2020

rustbot commented Jun 8, 2020

varkor commented Jun 9, 2020

arora-aman commented Jun 22, 2020

taikulawo commented Jun 21, 2021

arora-aman commented Jun 21, 2021

taikulawo commented Jun 21, 2021

nikomatsakis commented Aug 17, 2021

ehuss commented Oct 2, 2021

nikomatsakis commented Oct 5, 2021

Tracking issue for RFC 2229, "Closures Capture Disjoint Fields" #53488

Tracking issue for RFC 2229, "Closures Capture Disjoint Fields" #53488

Comments

Centril commented Aug 19, 2018 • edited by nikomatsakis

Status

Implementation plan and status

Links, see also

eddyb commented Aug 19, 2018

samsartor commented Aug 21, 2018

ghedo commented Sep 5, 2019

tesuji commented May 15, 2020 • edited

Ixrec commented May 16, 2020

KiChjang commented May 16, 2020

nikomatsakis commented May 21, 2020

nikomatsakis commented Jun 8, 2020

rustbot commented Jun 8, 2020

varkor commented Jun 9, 2020

arora-aman commented Jun 22, 2020

taikulawo commented Jun 21, 2021

arora-aman commented Jun 21, 2021

taikulawo commented Jun 21, 2021

nikomatsakis commented Aug 17, 2021

ehuss commented Oct 2, 2021

nikomatsakis commented Oct 5, 2021

Centril commented Aug 19, 2018 •

edited by nikomatsakis

tesuji commented May 15, 2020 •

edited