This Week in Rust 345

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 .

Check out this week's This Week in Rust Podcast

Updates from Rust Community

News & Blog Posts

• A practical guide to async in Rust
• Secure Rust Guidelines - ANSSI (National Cybersecurity Agency of France)
• Faster Rust development on AWS EC2 with VSCode
• Rust verification tools
• Examining ARM vs X86 Memory Models with Rust
• Disk space and LTO improvements
• Building a faster CouchDB View Server in Rust
• Implementing a Job queue with SQLx and Postgres
• Rust + Actix + CosmosDB (MongoDB) tutorial api
• Extremely Simple Rust Rocket Framework Tutorial
• Build a Smart Bookmarking Tool with Rust and Rocket
• A Future is a Suspending Scheduler
• Cross building Rust GStreamer plugins for the Raspberry Pi
• xi-editor retrospective
• This month in my Database project written in Rust
• A Few More Reasons Rust Compiles Slowly
• Fixing Rust's test suite on RISC-V
• Protobuf code generation in Rust
• Tracking eye centers location with Rust & OpenCV
• Using rust, blurz to read from a BLE device
• rust-analyzer changelog #31
• IntelliJ Rust Changelog #125
• [video] Manipulating ports, virtual ports and pseudo terminals - Rust Wrocław Webinar
• [video] Rust Stream: Iterators

Crate of the Week

This week's crate is print_bytes , a library to print arbitrary bytes to a stream as losslessly as possible.

Thanks to dylni for the suggestion!

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!

• Database in Rust is looking for contributors

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

• Gooseberry: Set the kb_dir somewhere more accessible to the user
• Ruma: Add directory and profile query endpoints

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

Updates from Rust Core

339 pull requests were merged in the last week

• move leak-check to during coherence, candidate eval
• account for multiple impl/dyn Trait in return type when suggesting '_
• tweak binop errors
• adds a clearer message for when the async keyword is missing from a function
• allow dynamic linking for iOS/tvOS targets
• always capture tokens for macro_rules! arguments
• change heuristic for determining range literal
• check for assignments between non-conflicting generator saved locals
• const prop: erase all block-only locals at the end of every block
• emit line info for generator variants
• explain move errors that occur due to method calls involving self
• fix handling of reserved registers for ARM inline asm
• improve compiler error message for wrong generic parameter order
• point at the call span when overflow occurs during monomorphization
• provide suggestions for some moved value errors
• self contained linking option
• perform obligation deduplication to avoid buggy ExistentialMismatch
• show the values and computation that would overflow a const evaluation or propagation
• stabilize #![feature(const_if_match)] and #![feature(const_loop)]
• A way forward for pointer equality in const eval
• the const propagator cannot trace references
• warn if linking to a private item
• improper_ctypes_definitions lint
• add Windows system error codes that should map to io::ErrorKind::TimedOut
• errors: use -Z terminal-width in JSON emitter
• proc_macro: stop flattening groups with dummy spans
• rustc_lint: only query typeck_tables_of when a lint needs it
• rustdoc: fix doc aliases with crate filtering
• chalk: .chalk file syntax writer
• chalk: add method to get repr data of an ADT to ChalkDatabase
• chalk: fix built-in Fn impls when generics are involved
• chalk: fix coherence issue with associated types in generic bound
• miri: implement rwlocks on Windows
• miri: supply our own implementation of the CTFE pointer comparison intrinsics
• shortcuts for min/max on ordinary BTreeMap/BTreeSet iterators
• add TryFrom<{int}> for NonZero{int}
• add a fast path for std::thread::panicking .
• add [T]::partition_point
• add unstable core::mem::variant_count intrinsic
• added io forwarding methods to the stdio structs
• stabilize leading_trailing_ones
• impl PartialEq<Vec<B>> for &[A], &mut [A]
• forward Hash::write_iN to Hash::write_uN
• libc: add ancillary socket data accessor functions for solarish OSes
• libc: FreeBSD: machine register structs
• libc: add wexecv, wexecve, wexecvp, wexecvpe
• cargo: add support for workspace.metadata table
• cargo: adding environment variable CARGO_PKG_LICENSE_FILE
• cargo: enable "--target-dir" in "cargo install"
• cargo: expose built cdylib artifacts in the Compilation structure
• cargo: improve support for non- master main branches
• docs.rs: don't panic when a crate doesn't exist for target-redirect
• docs.rs: improve executing tests
• clippy: lint iterator.map(|x| x)
• clippy: new lint: suggest ptr::read instead of mem::replace(..., uninitialized())
• clippy: clippy-driver: pass all args to rustc if --rustc is present
• clippy: cmp_owned: handle when PartialEq is not implemented symmetrically
• rustfmt: do not reorder module declaration with #![macro_use]
• rustfmt: don't reformat with errors unless --force flag supplied

Rust Compiler Performance Triage

• 2020-06-30 . Three regressions, two of them on rollups; two improvements, one on a rollup.

Approved RFCs

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

• RFC: Deduplicate Cargo workspace information

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

• Inline const expressions and patterns
• Inline assembly

Tracking Issues & PRs

• [disposition: merge] impl From<char> for String
• [disposition: merge] mv std libs to std/
• [disposition: merge] Stabilize transmute in constants and statics but not const fn
• [disposition: merge] added .collect() into String from Box<str>
• [disposition: merge] Stabilize const_type_id feature

New RFCs

• Linking modifiers for native libraries
• Hierarchic anonymous life-time
• Portable packed SIMD vector type
• crates.io token scopes

Upcoming Events

Online

• June 30. Berlin, DE - Remote - Berlin Rust - Rust and Tell
• July 1. Johannesburg, ZA - Remote - Monthly Joburg Rust Chat!
• July 1. Dublin, IE - Remote - Rust Dublin - July Remote Meetup
• July 1. Indianapolis, IN, US - Indy Rust - Indy.rs - with Social Distancing
• July 13. Seattle, WA, US - Seattle Rust Meetup - Monthly Meetup

North America

• June 30. Dallas, TX, US - Dallas Rust - Last Tuesday
• July 8. Atlanta, GA, US - Rust Atlanta - Grab a beer with fellow Rustaceans
• July 9. Lehi, UT, US - Utah Rust - The Blue Pill: Rust on Microcontrollers

Asia Pacific

• July 6. Auckland, NZ - Rust AKL

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.

Rust Jobs

• Senior Software Engineer - Backend at LogDNA, Remote, US
• Senior Software Engineer - Protocols in Rust at Ockam, Remote

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

Quote of the Week

– trentj on rust-users

Thanks to Ivan Tham for the suggestions!

Please submit quotes and vote for next week!

This Week in Rust is edited by: nellshamrell , llogiq , and cdmistman .

Discuss on r/rust