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.

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Find all #Rust2019 posts at Read Rust.

Crate of the Week

This week's crate is ropey, an editable text buffer data structure. Thanks to Vikrant Chaudhary 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!

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

189 pull requests were merged in the last week

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

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Quote of the Week

Right. I've never even used this impl, but my first thought upon seeing the question "I have an Iterator of X and need a Y" was to look at the FromIterator impls of Y.

If that impl didn't exist, I'd then look for the following:

  • Other FromIterator<X> impls for String to see if any of those X can easily be produced from char (and then I would call map before .collect()).
  • impl FromIterator<char> for Vec<u8>. If this existed I would use String::from_utf8(iterator.collect()).
  • impl Add<char> for String. If this existed, I would use .fold(String::new(), |s, c| s + c)
  • methods of char to see if there's anything that lets you obtain the UTF8 bytes. Indeed, there is encode_utf8, which even gives a &mut str, so one can write rust .fold(String::new(), |s, c| { let mut buffer = [u8; 4]; s += &*c.encode_utf8(&mut buffer); s })
  • idly check the inherent methods of String for whatever pops out at me

and if I could still find nothing after all of that I'd slam my head into a wall somewhere.

– Michael Lamparski on rust-users

Thanks to Cauê Baasch De Souza for the suggestion!

Please submit your quotes for next week!

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

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