Repository: rust
Issue: Tracking Issue for experimental `yeet` expressions (`feature(yeet_expr)`)
Labels: T-lang,C-tracking-issue

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This is a tracking issue for *experimenting* with the ["throw expression" idea from RFC#0243](https://rust-lang.github.io/rfcs/0243-trait-based-exception-handling.html#throw-and-throws).
The feature gate for the issue is `#![feature(yeet_expr)]`.

[Per the lang process](https://lang-team.rust-lang.org/how_to/propose.html), this cannot go further than experimenting without an approved RFC -- and will certainly not stabilize under the name `yeet`.  Please try this out and give experience reports, but be aware that it may well change drastically or be removed entirely.

Currently the primary purpose of the feature is to ensure that redesigns of the `Try` trait (#84277) are compatible with potentially doing this in the future, and secondarily to experiment with whether this is worth having *as an expression*, or whether it should be removed in favour of a pure-library approach.

Because the `do yeet` syntax is explicitly temporary, do not expect various ecosystem tools to support it, especially not those which have stability promises.

Lang initiative: https://github.com/rust-lang/lang-team/issues/160
Tracking issue for standard library additions: #96374

### About tracking issues

Tracking issues are used to record the overall progress of implementation.
They are also used as hubs connecting to other relevant issues, e.g., bugs or open design questions.
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### Steps
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- [ ] Implement the RFC (cc @rust-lang/XXX -- can anyone write up mentoring
      instructions?)
- [ ] Adjust documentation ([see instructions on rustc-dev-guide][doc-guide])
- [ ] Stabilization PR ([see instructions on rustc-dev-guide][stabilization-guide])

[stabilization-guide]: https://rustc-dev-guide.rust-lang.org/stabilization_guide.html#stabilization-pr
[doc-guide]: https://rustc-dev-guide.rust-lang.org/stabilization_guide.html#documentation-prs

### Unresolved Questions
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- [ ] Is this even worth having syntax for?
- [ ] What's the right keyword for it? `yeet` is used for now to avoid priming any particular choice.
- [ ] How should this work semantically?

### Implementation history

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- #96376