Hello and welcome to another issue of This Week in Rust! Rust is a programming language empowering everyone to build reliable and efficient software. This is a weekly summary of its progress and community. Want something mentioned? Tweet us at @ThisWeekInRust or send us a pull request. Want to get involved? We love contributions.

This Week in Rust is openly developed on GitHub. If you find any errors in this week's issue, please submit a PR.

Updates from Rust Community

Official

Announcing Rust 1.55.0
[video] RustConf 2021 Video Stream

Newsletters

Project/Tooling Updates

Observations/Thoughts

Rust Walkthroughs

Miscellaneous

Crate of the Week

This week's crate is qcell, with a type that works like a compile-time RefCell.

Thanks to Soni L. for the suggestion!

Please submit your suggestions and votes for next week!

Call for Participation

Always wanted to contribute to open-source projects but didn't know where to start? Every week we highlight some tasks from the Rust community for you to pick and get started!

Some of these tasks may also have mentors available, visit the task page for more information.

If you are a Rust project owner and are looking for contributors, please submit tasks here.

Updates from Rust Core

278 pull requests were merged in the last week

Rust Compiler Performance Triage

Fairly busy week, with some large improvements on several benchmarks. Several larger rollups landed, in part due to recovery from a temporary CI outage, and continued CI trouble since then. This is likely the cause for the somewhat unusual presence of rollups in our results.

Triage done by @simulacrum. Revision range: 69c4aa290..9f85cd6

2 Regressions, 2 Improvements, 4 Mixed; 2 of them in rollups

31 comparisons made in total

Full report here.

Approved RFCs

Changes to Rust follow the Rust RFC (request for comments) process. These are the RFCs that were approved for implementation this week:

Final Comment Period

Every week the team announces the 'final comment period' for RFCs and key PRs which are reaching a decision. Express your opinions now.

RFCs

No RFCs are currently in the final comment period.

Tracking Issues & PRs

[disposition: close] Disable unused_must_use for statically known bools
[disposition: merge] Make #[derive(A, B, ...)] cfg-eval its input only for A, B, ... and stabilize feature(macro_attributes_in_derive_output)
[disposition: merge] Make *const (), *mut () okay for FFI
[disposition: merge] Tracking issue Iterator map_while

New RFCs

No new RFCs were proposed this week.

Upcoming Events

Online

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