Rollup merge of #119978 - compiler-errors:async-closure-captures, r=oli-obk

Move async closure parameters into the resultant closure's future eagerly

Move async closure parameters into the closure's resultant future eagerly.

Before, we used to desugar `async |p1, p2, ..| { body }` as `|p1, p2, ..| { || async { body } }`. Now, we desugar the above like `|p1, p2, ..| { async move { let p1 = p1; let p2 = p2; ... body } }`. This mirrors the same desugaring that `async fn` does with its parameter types, and the compiler literally uses the same code via a shared helper function.

This removes the necessity for E0708, since now expressions like `async |x: i32| { x }` will not give you confusing borrow errors.

This does *not* fix the case where async closures have self-borrows. This will come with a general implementation of async closures, which is still in the works.

r? oli-obk
This commit is contained in:
Matthias Krüger 2024-01-18 10:34:18 +01:00 committed by GitHub
commit 088a6f4153
No known key found for this signature in database
GPG key ID: B5690EEEBB952194

Diff content is not available