rust/compiler/rustc_infer
Dylan DPC 6cb13585d0
Rollup merge of #110454 - oli-obk:limited_impl_trait_in_assoc_type, r=compiler-errors
Require impl Trait in associated types to appear in method signatures

This implements the limited version of TAIT that was proposed in https://github.com/rust-lang/rust/issues/107645#issuecomment-1477899536

Similar to `impl Trait` in return types, `impl Trait` in associated types may only be used within the impl block which it is a part of. To make everything simpler and forward compatible to getting desugared to a plain type alias impl trait in the future, we're requiring that any associated functions or constants that want to register hidden types must be using the associated type in their signature (type of the constant or argument/return type of the associated method. Where bounds mentioning the associated type are ignored).

We have preexisting tests checking that this works transitively across multiple associated types in situations like

```rust
impl Foo for Bar {
    type A = impl Trait;
    type B = impl Iterator<Item = Self::A>;
    fn foo() -> Self::B { ...... }
}
```
2023-05-13 11:05:32 +05:30
..
src Rollup merge of #110454 - oli-obk:limited_impl_trait_in_assoc_type, r=compiler-errors 2023-05-13 11:05:32 +05:30
Cargo.toml Add rustc_fluent_macro to decouple fluent from rustc_macros 2023-04-18 18:56:22 +00:00
messages.ftl Spelling - compiler 2023-04-17 16:09:18 -04:00