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

• A Q4 Recap & 2022 Reflection from Rebecca Rumbul

Project/Tooling Updates

• rust-analyzer changelog #162
• fltk-rs in 2022
• shuttle - Release v0.8.0
• This Week in Fyrox
• gitoxide - The year in retrospective, and what's to come
• The AeroRust community - 3 years birthday (and the roadmap for 2023)
• SeaQuery 0.28.0 - A dynamic query builder for SeaORM
• Databend 2022 Recap

Observations/Thoughts

• State Machines III: Type States
• Rust — vim — code completion
• How to Test
• Embedded Rust and Embassy: DMA Controllers
• Parsing TFTP in Rust
• Rustdoc JSON in 2022
• From PHP to Rust: Migrating a REST API between these two languages. (Part I)
• React + Rust + Wasm: Play an Animated 3D Model
• Open Source Grindset Explained (with a Rust example)

Rust Walkthroughs

• Building a Simple DB in Rust - Part 1
• Microservices with Rust and WASM using Fermyon
• Compiling Brainfuck code - Part 4: A Static Compiler
• Rusty Circuit Breaker 🦀
• Zero-dependency random number generation in Rust

Miscellaneous

• Rust 101: an open-source university course
• [video] If Rust Compiles, It WORKS (Testing not needed 📚)
• [video] Introduction to Axum
• [video] Ergonomic APIs for hard problems - Raph Levien

Crate of the Week

This week's crate is Sniffnet, a cross-platform GUI application to analyze your network traffic.

Thanks to Gyuly Vgc 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!

No calls for participation this week. Keep an eye out for more places to contribute next week!

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

Updates from the Rust Project

291 pull requests were merged in the last week

• CFI: monomorphize transparent ADTs before typeid
• account for match expr in single line
• account for macros in const generics
• account for multiple multiline spans with empty padding
• adjust message on non-unwinding panic
• allow trait method paths to satisfy const Fn bounds
• always suggest as MachineApplicable in recover_intersection_pat
• detect diff markers in the parser
• detect when method call on LHS might be shadowed
• dont use --merge-base during bootstrap formatting subcommand
• emit fewer errors on invalid #[repr(transparent)] on enum
• encode spans relative to the enclosing item -- enable on nightly
• error parsing lifetime following by Sized and message + between them
• fix confusing diagnostic when attempting to implementing trait for tuple
• format only modified files
• on unsized locals with explicit types suggest &
• only deduplicate stack traces for good path bugs
• give the correct track-caller location with MIR inlining
• implement allow-by-default multiple_supertrait_upcastable lint
• improve heuristics whether format_args string is a source literal
• make trait/impl where clause mismatch on region error a bit more actionable
• merge multiple mutable borrows of immutable binding errors
• partially fix explicit_outlives_requirements lint in macros
• properly calculate best failure in macro matching
• provide a better error and a suggestion for Fn traits with lifetime params
• provide local extern function arg names
• recover fn keyword as Fn trait in bounds
• remove unreasonable help message for auto trait
• silence knock-down errors on [type error] bindings
• suggest Pin::as_mut when encountering borrow error
• suggest impl Iterator when possible for _ return type
• suggest rewriting a malformed hex literal if we expect a float
• suppress errors due to TypeError not coercing with inference variables
• trim more paths in obligation types
• miri: cargo-miri: use rustc to determine the output filename
• miri: handle unknown targets more gracefully
• miri: simplify path joining code a bit
• miri: support using a JSON target file
• miri: tweaks to retag diagnostic handling
• use some more const_eval_select in pointer methods for compile times
• more inference-friendly API for lazy
• more verbose Debug implementation of std::process:Command
• add #[inline] markers to once_cell methods
• unify id-based thread parking implementations
• available_parallelism:gracefully handle zero value cfs_period_us
• catch panics/unwinding in destruction of thread-locals
• cargo: asymmetric tokens
• cargo: reasons for rebuilding
• clippy: fix false negative in needless_return
• clippy: fix match_single_binding suggestion introducing an extra semicolon
• clippy: move mutex_atomic to restriction
• rust-analyzer: derive Hash
• rust-analyzer: enum variant discriminants hints
• rust-analyzer: diagnose private assoc item accesses
• rust-analyzer: diagnose private field accesses
• rust-analyzer: implement yeeting
• rust-analyzer: fall back to inaccessible associated functions and constants if no visible resolutions are found
• rust-analyzer: improve exit point highlighting for for and while loops in tail position
• rust-analyzer: merge multiple intersecting ranges
• rust-analyzer: prefix prelude items whose name collides in current scope
• rust-analyzer: type check unstable try{} blocks
• rust-analyzer: support multi-character punct tokens in MBE
• rust-analyzer: write down adjustments introduced by binary operators

Rust Compiler Performance Triage

Fairly busy week with some massive performance improvements at the expense of some significant albeit smaller regressions. The main wins came in a long-standing PR from @cjgillot to enable encoding spans in metadata relative to their enclosing item. This causes more work in full compilation which causes some regressions up to 5% but can lead to very large wins in incremental compilation scenarios (up to ~70%). For example, the clap crate compiles 68% faster after a small 1 line change than it did previously.

Triage done by @rylev. Revision range: b38a6d..b43596

Summary:

1 Regressions, 1 Improvements, 4 Mixed; 1 of them in rollups 47 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:

• 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.

RFCs

• No RFCs entered Final Comment Period this week.

Tracking Issues & PRs

• [disposition: merge] Only include stable lints in rustdoc::all group
• [disposition: merge] Don't derive Debug for OnceWith & RepeatWith
• [disposition: merge] PhantomData layout guarantees
• [disposition: merge] Add O(1) Vec -> VecDeque conversion guarantee
• [disposition: merge] Stabilize ::{core,std}::pin::pin!
• [disposition: merge] Stabilize main_separator_str
• [disposition: merge] Loosen the bound on the Debug implementation of Weak.

New and Updated RFCs

• No New or Updated RFCs were created this week.

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 2023-01-04 - 2023-02-01 🦀

Virtual

• 2023-01-04 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2023-01-04 | Virtual (Stuttgart, DE) | Rust Community Stuttgart
  • Rust-Meetup
• 2023-01-05 | Virtual (Charlottesville, VA, US) | Charlottesville Rust Meetup
  • Part 2: Exploring USB with Rust
• 2023-01-10 | Virtual (Dallas, TX, US) | Dallas Rust
  • Second Tuesday
• 2023-01-11 | Virtual (Boulder, CO, US) | Boulder Elixir and Rust
  • Monthly Meetup
• 2023-01-12 | Virtual (San Francisco, CA, US; Stockholm, SE; New York, NY US) | Microsoft Reactor San Francisco | Microsoft Reactor New York
  • Crack code interview problems in Rust - Ep. 1 | Stockholm Mirror | New York Mirror
• 2023-01-12 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Rust Nürnberg online
• 2023-01-14 | Virtual | Rust GameDev
  • Rust GameDev Monthly Meetup
• 2023-01-16 | Virtual (San Francisco, CA, US; São Paulo, BR; New York, NY, US) | Microsoft Reactor San Francisco and Microsoft Reactor São Paulo and Microsoft Reactor New York
  • Primeros pasos con Rust - Qué es y Configuración el entorno de desarrollo | São Paulo Mirror | New York Mirror
• 2023-01-17 | Virtual (Berlin, DE) | OpenTechSchool Berlin
  • Rust Hack and Learn
• 2023-01-17 | Virtual (San Francisco, CA, US; São Paulo, BR, New York, NY, US) | Microsoft Reactor San Francisco and Microsoft Reactor São Paulo and Microsoft Reactor New York
  • Primeros pasos con Rust - Creación del primer programa de Rust | *São Paulo Mirror | New York Mirror
• 2023-01-17 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful
• 2023-01-18 | Virtual (San Francisco, CA, US; São Paulo, BR; New York, NY US) | Microsoft Reactor San Francisco and Microsoft Reactor São Paulo and Microsoft Reactor New York
  • Primeros pasos con Rust: QA y horas de comunidad | Sao Paulo Mirror | New York Mirror
• 2023-01-18 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2023-01-26 | Virtual (Charlottesville, VA, US) | Charlottesville Rust Meetup
  • Rust Lightning Talks!
• 2023-01-31 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2023-02-01 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing

Asia

• 2023-01-15 | Tokyo, JP | Tokyo Rust Meetup
  • Property-Based Testing in Rust

Europe

• 2023-01-12 | Enschede, NL | Dutch Rust Meetup
  • Rust Meetup - Subject TBA
• 2023-01-20 | Stuttgart, DE | Rust Community Stuttgart
  • OnSite Meeting
• 2023-01-25 | Paris, FR | Rust Paris
  • Rust Paris meetup #55

North America

• 2023-01-05 | Lehi, UT, US | Utah Rust
  • Lightning Talks 'n' Chill (a.k.a. Show & Tell), with Pizza!
• 2023-01-09 | Minneapolis, MN, US | Minneapolis Rust Meetup
  • Happy Hour and Beginner Embedded Rust Hacking Session (#2!)
• 2023-01-11 | Austin, TX, US | Rust ATX
  • Rust Lunch
• 2023-01-17 | San Francisco, CA, US | San Francisco Rust Study Group
  • Rust Hacking in Person
• 2023-01-26 | Copenhagen, DK | Copenhagen Rust group
  • Rust Hack Night #32
• 2023-01-26 | Lehi, UT, US | Utah Rust
  • Building a Rust Playground with WASM and Lane and Food!

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

You haven’t “fooled” rustc, you are using unsafe code. Unsafe code means that all you can do is fool yourself.

– Frank Steffahn on rust-users

Thanks to Quine Dot 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.

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Discuss on r/rust