Skip to content

std: refactor explanation of NonNull#141946

Merged
bors merged 1 commit intorust-lang:masterfrom
xizheyin:141933
Jun 17, 2025
Merged

std: refactor explanation of NonNull#141946
bors merged 1 commit intorust-lang:masterfrom
xizheyin:141933

Conversation

@xizheyin
Copy link
Member

@xizheyin xizheyin commented Jun 3, 2025 •
edited
Loading

Fixes #141933

I cut out the excessive explanation and used an example to explain how to maintain invariance, but I think what is quoted in the rust reference in the document needs to be added with a more layman's explanation and example.

(I'm not sure if I deleted too much)

r? @workingjubilee

@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-libs Relevant to the library team, which will review and decide on the PR/issue. labels Jun 3, 2025
workingjubilee
workingjubilee reviewed Jun 3, 2025
View reviewed changes
@xizheyin
std: simplify NonNull variance documentation
8713973 
Streamlined the explanation of covariance for `NonNull<T>`,
focusing on practical usage and reducing scary explanation.
Added a concise example for cases where invariance is required,
showing how to use `PhantomData<Cell<T>>

Signed-off-by: xizheyin <xizheyin@smail.nju.edu.cn>
@xizheyin
Copy link
Member Author

xizheyin commented Jun 3, 2025

I've avoided big changes this time, removing some of the “scary” descriptions and replacing them with more practical advice, and adding more specific explanations for the examples.

@xizheyin xizheyin requested a review from workingjubilee June 9, 2025 05:27
@workingjubilee
Copy link
Member

workingjubilee commented Jun 11, 2025 •
edited
Loading

Hm. I know I filed the issues but I wasn't really expecting to get two PRs immediately and requested on them, I kinda expected them to hit the rotation, and this is a slightly more tricky PR to judge when biased by being the reporter. So I'm going to pass them onto the rotation, sorry! ^^;

r? libs

@rustbot
Copy link
Collaborator

rustbot commented Jun 11, 2025

Failed to set assignee to 'd: invalid assignee

Note: Only org members with at least the repository "read" role, users with write permissions, or people who have commented on the PR may be assigned.

@rustbot rustbot assigned thomcc and unassigned workingjubilee Jun 11, 2025
@workingjubilee
Copy link
Member

workingjubilee commented Jun 11, 2025

lol
r? libs

@rustbot rustbot assigned jhpratt and unassigned thomcc Jun 11, 2025
@jhpratt
Copy link
Member

jhpratt commented Jun 17, 2025

@bors r+ rollup

@bors
Copy link
Collaborator

bors commented Jun 17, 2025

📌 Commit 8713973 has been approved by jhpratt

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jun 17, 2025
@workingjubilee workingjubilee mentioned this pull request Jun 17, 2025
Merged
rust-bors bot added a commit that referenced this pull request Jun 17, 2025
@rust-bors
Auto merge of #142613 - workingjubilee:rollup-yuod2hg, r=<try>
69b2373 
Rollup of 13 pull requests

Successful merges:

 - #138538 (Make performance description of String::{insert,insert_str,remove} more precise)
 - #141946 (std: refactor explanation of `NonNull`)
 - #142216 (Miscellaneous RefCell cleanups)
 - #142542 (Manually invalidate caches in SimplifyCfg.)
 - #142563 (Refine run-make test ignores due to unpredictable `i686-pc-windows-gnu` unwind mechanism)
 - #142570 (Reject union default field values)
 - #142584 (Handle same-crate macro for borrowck semicolon suggestion)
 - #142585 (Update books)
 - #142586 (Fold unnecessary `visit_struct_field_def` in AstValidator)
 - #142587 (Make sure to propagate result from `visit_expr_fields`)
 - #142595 (Revert overeager warning for misuse of `--print native-static-libs`)
 - #142598 (Set elf e_flags on ppc64 targets according to abi)
 - #142601 (Add a comment to `FORMAT_VERSION`.)

r? `@ghost`
`@rustbot` modify labels: rollup
<!-- homu-ignore:start -->
[Create a similar rollup](https://bors.rust-lang.org/queue/rust?prs=138538,141946,142216,142542,142563,142570,142584,142585,142586,142587,142595,142598,142601)
<!-- homu-ignore:end -->
try-job: dist-apple-various
workingjubilee added a commit to workingjubilee/rustc that referenced this pull request Jun 17, 2025
@workingjubilee
Rollup merge of rust-lang#141946 - xizheyin:141933, r=jhpratt
be6b529 
std: refactor explanation of `NonNull`

Fixes rust-lang#141933

I cut out the excessive explanation and used an example to explain how to maintain invariance, but I think what is quoted in the *rust reference* in the document needs to be added with a more layman's explanation and example.

(I'm not sure if I deleted too much)

r? ``@workingjubilee``
@workingjubilee workingjubilee mentioned this pull request Jun 17, 2025
Closed
bors added a commit that referenced this pull request Jun 17, 2025
@bors
Auto merge of #142614 - workingjubilee:rollup-g5qf7y3, r=workingjubilee
1b4aa42 
Rollup of 10 pull requests

Successful merges:

 - #138538 (Make performance description of String::{insert,insert_str,remove} more precise)
 - #141946 (std: refactor explanation of `NonNull`)
 - #142216 (Miscellaneous RefCell cleanups)
 - #142371 (avoid `&mut P<T>` in `visit_expr` etc methods)
 - #142377 (Try unremapping compiler sources)
 - #142517 (Windows: Use anonymous pipes in Command)
 - #142542 (Manually invalidate caches in SimplifyCfg.)
 - #142563 (Refine run-make test ignores due to unpredictable `i686-pc-windows-gnu` unwind mechanism)
 - #142570 (Reject union default field values)
 - #142584 (Handle same-crate macro for borrowck semicolon suggestion)

r? `@ghost`
`@rustbot` modify labels: rollup
rust-bors bot added a commit that referenced this pull request Jun 17, 2025
@rust-bors
Auto merge of #142614 - workingjubilee:rollup-g5qf7y3, r=<try>
a62049a 
Rollup of 10 pull requests

Successful merges:

 - #138538 (Make performance description of String::{insert,insert_str,remove} more precise)
 - #141946 (std: refactor explanation of `NonNull`)
 - #142216 (Miscellaneous RefCell cleanups)
 - #142371 (avoid `&mut P<T>` in `visit_expr` etc methods)
 - #142377 (Try unremapping compiler sources)
 - #142517 (Windows: Use anonymous pipes in Command)
 - #142542 (Manually invalidate caches in SimplifyCfg.)
 - #142563 (Refine run-make test ignores due to unpredictable `i686-pc-windows-gnu` unwind mechanism)
 - #142570 (Reject union default field values)
 - #142584 (Handle same-crate macro for borrowck semicolon suggestion)

r? `@ghost`
`@rustbot` modify labels: rollup
<!-- homu-ignore:start -->
[Create a similar rollup](https://bors.rust-lang.org/queue/rust?prs=138538,141946,142216,142371,142377,142517,142542,142563,142570,142584)
<!-- homu-ignore:end -->
try-job: dist-aarch64-apple
bors added a commit that referenced this pull request Jun 17, 2025
@bors
Auto merge of #142613 - workingjubilee:rollup-yuod2hg, r=workingjubilee
f3db639 
Rollup of 13 pull requests

Successful merges:

 - #138538 (Make performance description of String::{insert,insert_str,remove} more precise)
 - #141946 (std: refactor explanation of `NonNull`)
 - #142216 (Miscellaneous RefCell cleanups)
 - #142542 (Manually invalidate caches in SimplifyCfg.)
 - #142563 (Refine run-make test ignores due to unpredictable `i686-pc-windows-gnu` unwind mechanism)
 - #142570 (Reject union default field values)
 - #142584 (Handle same-crate macro for borrowck semicolon suggestion)
 - #142585 (Update books)
 - #142586 (Fold unnecessary `visit_struct_field_def` in AstValidator)
 - #142587 (Make sure to propagate result from `visit_expr_fields`)
 - #142595 (Revert overeager warning for misuse of `--print native-static-libs`)
 - #142598 (Set elf e_flags on ppc64 targets according to abi)
 - #142601 (Add a comment to `FORMAT_VERSION`.)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 94ce4b5 into rust-lang:master Jun 17, 2025
10 checks passed
@rustbot rustbot added this to the 1.89.0 milestone Jun 17, 2025
rust-timer added a commit that referenced this pull request Jun 17, 2025
@rust-timer
Unrolled build for #141946
483f9ba 
Rollup merge of #141946 - xizheyin:141933, r=jhpratt

std: refactor explanation of `NonNull`

Fixes #141933

I cut out the excessive explanation and used an example to explain how to maintain invariance, but I think what is quoted in the *rust reference* in the document needs to be added with a more layman's explanation and example.

(I'm not sure if I deleted too much)

r? `@workingjubilee`
github-actions bot pushed a commit to rust-lang/miri that referenced this pull request Jun 18, 2025
@bors
Auto merge of #142613 - workingjubilee:rollup-yuod2hg, r=workingjubilee
ba32451 
Rollup of 13 pull requests

Successful merges:

 - rust-lang/rust#138538 (Make performance description of String::{insert,insert_str,remove} more precise)
 - rust-lang/rust#141946 (std: refactor explanation of `NonNull`)
 - rust-lang/rust#142216 (Miscellaneous RefCell cleanups)
 - rust-lang/rust#142542 (Manually invalidate caches in SimplifyCfg.)
 - rust-lang/rust#142563 (Refine run-make test ignores due to unpredictable `i686-pc-windows-gnu` unwind mechanism)
 - rust-lang/rust#142570 (Reject union default field values)
 - rust-lang/rust#142584 (Handle same-crate macro for borrowck semicolon suggestion)
 - rust-lang/rust#142585 (Update books)
 - rust-lang/rust#142586 (Fold unnecessary `visit_struct_field_def` in AstValidator)
 - rust-lang/rust#142587 (Make sure to propagate result from `visit_expr_fields`)
 - rust-lang/rust#142595 (Revert overeager warning for misuse of `--print native-static-libs`)
 - rust-lang/rust#142598 (Set elf e_flags on ppc64 targets according to abi)
 - rust-lang/rust#142601 (Add a comment to `FORMAT_VERSION`.)

r? `@ghost`
`@rustbot` modify labels: rollup
github-actions bot pushed a commit to tautschnig/verify-rust-std that referenced this pull request Jun 24, 2025
@workingjubilee
Rollup merge of rust-lang#141946 - xizheyin:141933, r=jhpratt
e76ae1c 
std: refactor explanation of `NonNull`

Fixes rust-lang#141933

I cut out the excessive explanation and used an example to explain how to maintain invariance, but I think what is quoted in the *rust reference* in the document needs to be added with a more layman's explanation and example.

(I'm not sure if I deleted too much)

r? `@workingjubilee`
github-actions bot pushed a commit to tautschnig/verify-rust-std that referenced this pull request Jun 24, 2025
@bors
Auto merge of rust-lang#142613 - workingjubilee:rollup-yuod2hg, r=wor…
a46ec5c 
…kingjubilee

Rollup of 13 pull requests

Successful merges:

 - rust-lang#138538 (Make performance description of String::{insert,insert_str,remove} more precise)
 - rust-lang#141946 (std: refactor explanation of `NonNull`)
 - rust-lang#142216 (Miscellaneous RefCell cleanups)
 - rust-lang#142542 (Manually invalidate caches in SimplifyCfg.)
 - rust-lang#142563 (Refine run-make test ignores due to unpredictable `i686-pc-windows-gnu` unwind mechanism)
 - rust-lang#142570 (Reject union default field values)
 - rust-lang#142584 (Handle same-crate macro for borrowck semicolon suggestion)
 - rust-lang#142585 (Update books)
 - rust-lang#142586 (Fold unnecessary `visit_struct_field_def` in AstValidator)
 - rust-lang#142587 (Make sure to propagate result from `visit_expr_fields`)
 - rust-lang#142595 (Revert overeager warning for misuse of `--print native-static-libs`)
 - rust-lang#142598 (Set elf e_flags on ppc64 targets according to abi)
 - rust-lang#142601 (Add a comment to `FORMAT_VERSION`.)

r? `@ghost`
`@rustbot` modify labels: rollup
@xizheyin xizheyin deleted the 141933 branch July 21, 2025 14:27
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

@workingjubilee workingjubilee Awaiting requested review from workingjubilee

Assignees

@jhpratt jhpratt

Labels

S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-libs Relevant to the library team, which will review and decide on the PR/issue.

Projects

None yet

Milestone

1.89.0

Development

Successfully merging this pull request may close these issues.

Reexplain NonNull's covariance details more concisely

6 participants

@xizheyin @workingjubilee @rustbot @jhpratt @bors @thomcc

Comments