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? Tag us at @ThisWeekInRust on Twitter or @ThisWeekinRust on mastodon.social, 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

Foundation

• Rust Foundation Joins Open Infrastructure Foundation as Associate Member
• Rust Identified as Safer Coding Tool by NIST
• Rewarding Resilience: Rust & the U.S. National Cybersecurity Strategy

Project/Tooling Updates

• Helix editor 23.03 released
• Rustls 0.21.0 Released With Exciting New Features
• Slint 1.0: The Next-Generation Native GUI Toolkit Matures
• rust-analyzer changelog #175
• Introducing SeaStreamer - a stream processing toolkit for Kafka and Redis Streams
• youki 0.0.5 has been released
• Fluvio Connector Development Kit released

Observations/Thoughts

• Thoughts on async closures
• How to speed up the Rust compiler in March 2023
• Two things that Rust does better than C++
• Rust Tidbits #1
• Follow up on cracking ZIP archives in Rust
• 58 Rust Resources Every Learner Should Know in 2023
• [audio] AI-NC with Tom Miles
• [audio] Servo with Josh Matthews

Rust Walkthroughs

• Building a Classic Mac OS App in Rust
• Cross Compiling Rust Projects in GitHub Actions
• Rust on the CH32V003
• Build your own CountMinSketch in Rust
• Nine Rules for Creating Fast, Safe, and Compatible Data Structures in Rust (Part 1): Lessons from RangeSetBlaze
• A definitive guide to sealed traits in Rust
• [ZH] Build a Lua interpreter in Rust

Miscellaneous

• Rust for C#/.NET Developers
• [video] Rust Wasm-Bindgen in 2 Minutes: Bridging the Gap Between WASM & JavaScript

Crate of the Week

This week's crate is keshvar, a library providing a host of information on every country.

Thanks to Pouriya for the suggestion!

Please submit your suggestions and votes for next week!

Call for Participation

Always wanted to contribute to open-source projects but did not 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.

• Hyperswitch - Use newtype pattern for email addresses
• Hyperswitch - Determine card brand from card BIN
• Hyperswitch - Validate card number while accepting payment method information
• man-in-the-middle-proxy - Transparent mode
• man-in-the-middle-proxy - TLS Decoder
• man-in-the-middle-proxy - Edit and resend requests
• man-in-the-middle-proxy - Duplicate and resend requests
• rusticify - Arrows parallel mode
• ockam - Update ockam tcp-outlet create clap command to have defined default arguments
• ockam - Update ockam forwarder create clap command to have defined default arguments
• ockam - Display worker address in the output of ockam tcp-connection create clap command

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

Updates from the Rust Project

390 pull requests were merged in the last week

• initial support for return type notation (RTN)
• specialization involving RPITITs is broken so ignore the diagnostic differences
• add a builtin FnPtr trait that is implemented for all function pointers
• middle: emit error rather than delay bug when reaching limit
• closures always implement FnOnce in new solver
• correctly substitute GAT's type used in normalize_param_env in check_type_bounds
• do not consider elaborated projection predicates for objects in new solver
• don't ICE on DiscriminantKind projection in new solver
• don't ICE on placeholder consts in deep reject
• erase impl regions when checking for impossible to eagerly monomorphize items
• freshen normalizes-to hack goal RHS in the evaluate loop
• improve error message when writer is forgotten in write and writeln macro
• make init mask lazy for fully initialized/uninitialized const allocations
• numeric vars can only be unified with numerical types in deep reject
• simplify transmutes in MIR InstCombine
• stable MIR: Add basic MIR body datastructures
• stop special-casing 'static in evaluation
• suggest ..= when someone tries to create an overflowing range
• drop array patterns using subslices
• add IndexSlice to go with IndexVec
• use &IndexSlice instead of &IndexVec where possible
• partial stabilization of once_cell
• optimize LazyCell size
• drop unstable Option::contains, Result::contains, Result::contains_err
• use span of placeholders in format_args!() expansion
• change advance(_back)_by to return the remainder instead of the number of processed elements
• binary_heap: Optimize Extend implementation
• stabilize binary_heap_retain
• hashbrown: optimize insertion to only use a single lookup
• codegen_gcc: optimize bitreverse codegen
• cargo: add delays to network retries
• rustdoc + rustdoc-json support for feature(non_lifetime_binders)
• rustdoc: run more HIR validation to mirror rustc
• clippy: add large future lint
• clippy: added the unnecessary_box_returns lint
• clippy: flag bufreader.lines().filter_map(Result::ok) as suspicious
• clippy: add suggestions to extra_unused_type_parameters
• clippy: arithmetic_side_effects: correctly handle division and module when the right-hand-side is unknown
• clippy: fix nonminimal_bool #[allow] attributes
• clippy: fix allow attribute, items from macros in items_after_statements
• clippy: ignore file!() macro in print_literal, write_literal
• clippy: in uninit checking, add fallback for polymorphic types
• rust-analyzer: expand Macro Recursively: don't append "!" to non-bang macro name
• rust-analyzer: feat: pop a notification prompting the user to add a Cargo.toml of unlinked file to the linkedProjects
• rust-analyzer: fix stack overflow in is_ty_uninhabited_from
• rust-analyzer: add missing autoborrow adjustment for index expressions
• rust-analyzer: allow new, subsequent rust-project.json-based workspaces to get proc macro expansion
• rust-analyzer: canonicalize rust-project.json manifest path
• rust-analyzer: handle box and raw pointers correctly in builtin_deref
• rust-analyzer: lower adjusts in simple index except the last one
• rust-analyzer: properly handle local trait impls
• rust-analyzer: recover from pub() visibility modifier
• rust-analyzer: use struct_tail_without_normalization in Expectation::rvalue_hint
• rust-analyzer: use async block in async fn type inference
• rust-analyzer: limited syntax support for return type notations (RTN)
• rust-analyzer: missing runnable env on debug target

Rust Compiler Performance Triage

A large improvement in const evaluation (particularly for large types) in #109670 and a large improvement to many-paged rustdoc workloads in #109876 by removing quadratic behavior. Regressions are comparatively limited this week.

Triage done by @simulacrum. Revision range: cbc064b341be231403d181402a786cce7f1c73f1..7c96e40da81165beef4f273f44e96eeef5a1bd30

Summary:

1 Regressions, 4 Improvements, 3 Mixed; 2 of them in rollups 54 artifact 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:

• standard lazy types

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 entered Final Comment Period this week.

Tracking Issues & PRs

• [disposition: merge] rustdoc-search: add support for nested generics
• [disposition: merge] Tracking Issue for const_ptr_read
• [disposition: merge] Uplift clippy::{drop,forget}_{ref,copy} lints
• [disposition: close] Tracking issue for the #[alloc_error_handler] attribute (for no_std + liballoc)
• [disposition: merge] Implement Neg for signed non-zero integers.
• [disposition: merge] Tracking Issue for IsTerminal / is_terminal
• [disposition: close] Tracking Issue for array_zip

New and Updated RFCs

• [new] ABI-stabilize core::task::Waker

Call for Testing

An important step for RFC implementation is for people to experiment with the implementation and give feedback, especially before stabilization. The following RFCs would benefit from user testing before moving forward:

• No RFCs issued a call for testing this week.

If you are a feature implementer and would like your RFC to appear on the above list, add the new call-for-testing label to your RFC along with a comment providing testing instructions and/or guidance on which aspect(s) of the feature need testing.

Upcoming Events

Rusty Events between 2023-04-05 - 2023-05-03 🦀

Virtual

• 2023-04-05 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2023-04-05 | Virtual (Stuttgart, DE) | Rust Community Stuttgart
  • Rust-Meetup
• 2023-04-06 | Virtual (Tehran, IR) | Iran Rust Meetup
  • Rust Iran Meetup #9 - Let's Write An Async Executor
• 2023-04-08 | Virtual | Rust GameDev
  • Rust GameDev Monthly Meetup
• 2023-04-08 | Virtual | Ukrainian Rust Community
  • UA Rust Conference 2023
• 2023-04-11 | Virtual (Berlin, DE) | Berline.rs - OpenTechSchool Berlin
  • Rust Hack and Learn
• 2023-04-11 | Virtual (Dallas, TX, US) | Dallas Rust
  • Second Tuesday
• 2023-04-11 | Virtual | Rust Live
  • Rust Live: Asynchronous Rust
• 2023-04-11 | Virtual (Saarbrücken, DE) | Rust-Saar
  • Meetup: 28u16
• 2023-04-12 | Virtual (Boulder, CO, US) | Boulder Elixir and Rust
  • Monthly Meetup
• 2023-04-12 | Virtual (Cardiff, UK) | Rust and C++ Cardiff
  • Rust Atomics and Locks Book Club Launch!
• 2023-04-13 | Virtual (Charlottesville, VA, US) | Charlottesville Rust Meetup
  • Learning Rust By Building Small CLI Tools!
• 2023-04-13 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Rust Nürnberg online
• 2023-04-18 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful—Introducing duplicate! and the peculiarities of proc macros
• 2023-04-19 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2023-04-20 | Virtual (Munich, DE) | Rust Munich
  • Rust Munich 2023 / 2 - hybrid
• 2023-04-20 | Virtual (Stuttgart, DE) | Rust Community Stuttgart
  • Rust-Meetup
• 2023-04-25 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2023-04-26 | Virtual (Cardiff, UK) | Rust and C++ Cardiff
  • Rust-friendly websites and web apps
• 2023-04-27 | Virtual (Charlottesville, VA, US) | Charlottesville Rust Meetup
  • Testing Tock, how unit tests in Rust improve and teach
• 2023-04-29 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Deep Dive Session 3: Protohackers Exercises Mob Coding (as far as we get)
• 2023-05-02 | Virtual (Buffalo, NY, US) | Buffalo Rust Meetup
  • Buffalo Rust User Group, First Tuesdays
• 2023-05-03 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing

Asia

• 2023-04-08 | Beijing, CN | Rust Chinese Group
  • Rust Meetup Beijing
• 2023-04-08 | Kyoto, JP | Kansai Rust
  • Demystifying Closures
• 2023-04-12 | Kuala Lumpur, MY | Rust Malaysia; Telegram
  • Rust Meetup Malaysia April 2023: How far is Dioxus from React? by Ivan Tham | Map
• 2023-04-18 | Tokyo, JP | Tokyo Rust Meetup
  • Rewriting Relay's GraphQL Compiler in Rust

Europe

• 2023-04-05 | Cologne, DE | Rust Cologne
  • Embedded Rust
• 2023-04-06 | Lyon, FR | Rust Lyon
  • Rust Lyon Meetup #3
• 2023-04-13 | Roma, IT | Rust Roma
  • Rules engine: from good to awesome (and beyond) with Rust
• 2023-04-13 | Wrocław, PL | Rust Wrocław
  • Rust Wrocław Meetup #33
• 2023-04-19 | Paris, FR | Rust Paris
  • Rust Paris meetup #58
• 2023-04-19 | Trondheim, NO | Rust Trondheim
  • Rust Embedded with MicroBit:V2
• 2023-04-19 | Zurich, CH | Rust Zurich
  • sett: data encryption and transfer made easy(ier)
• 2023-04-20 | Aarhus, DK | Rust Aarhus
  • Rust Aarhus meetup #1 at Geanix
• 2023-04-20 | Munich, DE + Virtual | Rust Munich
  • Rust Munich 2023 / 2 - hybrid
• 2023-04-20 | Bern, CH | Rust Bern
  • First Rust Bern Meetup!
• 2023-04-21 | Stuttgart, DE | Rust Community Stuttgart
  • OnSite Meeting
• 2023-05-02 | Amsterdam, NL | Rust Developers Amsterdam Group
  • Fiberplane Rust Workshop
• 2023-05-10 | Amsterdam, NL | RustNL
  • RustNL 2023

North America

• 2023-04-08 | Durham, NC, US | Triangle Rust
  • Rust Social / Coffee Chat at Boxyard RTP
• 2023-04-13 | New York, NY, US | Rust NYC
  • Autometrics: Easily add metrics in Rust and understand them in Prometheus
• 2023-04-18 | San Francisco, CA, US | San Francisco Rust Study Group
  • Rust Hacking in Person

Oceania

• 2023-04-13 | Sydney, NSW, AU | Rust Sydney
  • 🦀 Lightning Talks - 🐰 April Thingy 😊

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

Jobs

Please see the latest Who's Hiring thread on r/rust

Quote of the Week

As usual, the borrow checker is correct: we are doing memory crimes.

– Ohad Ravid on his blog

Thanks to Jelte Fennema for the suggestion!

Please submit quotes and vote for next week!

This Week in Rust is edited by: nellshamrell, llogiq, cdmistman, ericseppanen, extrawurst, andrewpollack, U007D, kolharsam, joelmarcey, mariannegoldin, bennyvasquez.

Email list hosting is sponsored by The Rust Foundation

Discuss on r/rust