April Lang Team Design Meetings

Apr. 10, 2020 · Josh Triplett on behalf of the language team

We've scheduled our language team design meetings for April. We have plans for three meetings:

try blocks, Try traits, functions that try, oh my!

(Update: tentatively moved to May 4.)

Clear the path to stabilizing try blocks and the Try trait, and identify some next steps for function-level try.


  • Resolving Ok-wrapping for try blocks
  • Discuss revisions to the Try trait required for stabilization.
  • Discuss syntax for early exit from a try with an error (Err(e)?): fail, throw, raise, yeet, etc.
  • If we have time, talk some about possibilities for function-level try.

April 20 -- Edition planning

Plan the 2021 edition, with a checklist of language features we will need to land in 2020 if we want to ship them in Rust 2021. We hope to emerge from this meeting with a checklist to guide our efforts, which we can adapt through the process.

April 27 -- Type aliases and traits enforcement

Long-standing issue: type Foo<T: Trait> = ... doesn't enforce T: Trait.


  • Discuss the situation with type aliases and decide what actions we may want to take.
  • Or, if we don't reach a decision, decide what measurements we might need to reach one.
  • Ideally, decide about estebank's PR.

About the language team design meetings

The idea of the design meeting is that it's a time for us to have in-depth discussions on some particular topic. This might be a burning problem that we've discovered, an update on some existing design work, or a forward looking proposal.

The meetings are open for anyone to listen in and attend. They are typically also recorded and posted online, along with minutes, after the fact. They generally take place on Mondays at noon Eastern time, 9am Pacific time -- but for the precise scheduling you should check the lang team calendar. Scheduled meetings are subject to change and cancelation. In that case, the calendar events will be updated.