918d0ac38e
Combine `ty::Projection` and `ty::Opaque` into `ty::Alias` Implements https://github.com/rust-lang/types-team/issues/79. This PR consolidates `ty::Projection` and `ty::Opaque` into a single `ty::Alias`, with an `AliasKind` and `AliasTy` type (renamed from `ty::ProjectionTy`, which is the inner data of `ty::Projection`) defined as so: ``` enum AliasKind { Projection, Opaque, } struct AliasTy<'tcx> { def_id: DefId, substs: SubstsRef<'tcx>, } ``` Since we don't have access to `TyCtxt` in type flags computation, and because repeatedly calling `DefKind` on the def-id is expensive, these two types are distinguished with `ty::AliasKind`, conveniently glob-imported into `ty::{Projection, Opaque}`. For example: ```diff match ty.kind() { - ty::Opaque(..) => + ty::Alias(ty::Opaque, ..) => {} _ => {} } ``` This PR also consolidates match arms that treated `ty::Opaque` and `ty::Projection` identically. r? `@ghost` |
||
|---|---|---|
| .. | ||
| src | ||
| Cargo.toml | ||
| README.md | ||
For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.