Hello and welcome to another issue of This Week in Rust! Rust is a systems language pursuing the trifecta: safety, concurrency, and speed. 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

News & Blog Posts

• How to speed up the Rust compiler some more.
• Rust’s standard hash table types could go quadratic.
• Rust’s iterators are inefficient, and here’s what we can do about it.
• Goto statement considered (mostly) harmless: Translating C goto statements to Rust with Corrode, a C to Rust translator.
• This year in nom: 2.0 is here.
• First steps in Nom: Parsing pseudo GLSL.
• Writing GStreamer Elements in Rust (Part 3). Parsing data from untrusted sources like it’s 2016.
• Painless Rust tests and benches on iOS and Android with Dinghy.
• First Rust+GObject coding session.

Other Weeklies from Rust Community

• This week in Rust docs 32. Updates from the Rust documentation team.
• This week in Tock Embedded OS 9. Tock is a safe, multitasking operating system for low-power, low-memory microcontrollers.
• This week in Ruma 2016-11-27. Ruma is a Matrix homeserver written in Rust.
• This week in TiKV 2016-11-28. TiKV is a distributed Key-Value database.
• Way Cooler Alpha Update (2016 November). Way Cooler is a customizable tiling window manager written in Rust for Wayland.

Crate of the Week

Since there were no nominations, this week has to go without a Crate of the Week. Sorry. 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.

• [less easy] rayon: Parity with the Iterator trait.
• [easy] rust: Compiling libunwind with --test for arm-musl targets produces dynamically linked binaries.
• [less easy] servo: Make FetchMetadata reflect all possible response types.
• [easy] servo: Make HTTP redirect fetch return an error if redirecting to non-HTTP(S).

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

Updates from Rust Core

66 pull requests were merged in the last week. Not much, but there were a good number of awesome changes:

• Implement break with value (RFC #1624)
• Stabilized name resolution changes (RFC #1560)
• Implement panic-safe slicing (RFC #1679)
• Make more types uninhabited
• Pad const enums only once
• Simplify HashMap probing
• Reduce type construction calls, Reduce allocations while walking types, make HirVec smaller – nnethercote is at it again…
• Improve macro name resolution performance
• Forward ExactSizeIterator on some adapters (for improved performance in some cases)
• Faster .is_empty() for slice and vec iterators
• Faster character count
• .set_permissions(_) for open Files
• Lifetimes in associated types now a hard error
• Peekable now remembers seeing a None
• Epic AST/HIR symbol refactoring
• Simplified directory ownership (breaking change)
• Crate type metadata
• -Z print-type-sizes
• rustbuild can now bench
• Cargo now compiles OpenSSL from source on OS X

New Contributors

• fkjogu
• Paul Lietar
• Sam Estep
• Vickenty Fesunov

Approved RFCs

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

No RFCs were approved 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. This week's FCPs are:

• Require documentation for all new features.

New RFCs

No new RFCs were proposed this week.

Style RFCs

Style RFCs are part of the process for deciding on style guidelines for the Rust community and defaults for Rustfmt. The process is similar to the RFC process, but we try to reach rough consensus on issues (including a final comment period) before progressing to PRs. Just like the RFC process, all users are welcome to comment and submit RFCs. If you want to help decide what Rust code should look like, come get involved!

PRs:

• Customising Rustfmt.

Ready for PR:

• Statements.
• Imports (use).
• Comments.
• Simple blocks, { ... }.

Final comment period:

• match.

Other notable issues:

• block vs visual indentation.
• function declarations.

Upcoming Events

• 11/30. Rust Community Team Meeting at #rust-community on irc.mozilla.org.
• 11/30. Rust Documentation Team Meeting at #rust-docs on irc.mozilla.org.
• 12/1. Rust release triage.
• 12/1. Rust DC Hack Session — Part 2.
• 12/1. Rust Meetup, Irving, TX.
• 12/7. Rust Community Team Meeting at #rust-community on irc.mozilla.org.
• 12/7. Rust Documentation Team Meeting at #rust-docs on irc.mozilla.org.
• 12/7. Rust Community Team Meeting at #rust-community on irc.mozilla.org.
• 12/7. Rust Documentation Team Meeting at #rust-docs on irc.mozilla.org.
• 12/8. Columbus Rust Society.
• 12/12. Seattle Rust Meetup.
• 12/15. Rust Bay Area: Syn/Macros 1.1, Helix, and Binding C in OpenSSL.

If you are running a Rust event please add it to the calendar to get it mentioned here. Email the Rust Community Team for access.

fn work(on: RustProject) -> Money

• Paid Rust/PostgresQL OSS work.
• Mozilla Research Internship (US/INTL) - University 2017.

Tweet us at @ThisWeekInRust to get your job offers listed here!

Quote of the Week

No quote was selected for QotW.

Submit your quotes for next week!

This Week in Rust is edited by: nasa42, llogiq, and brson.