From 7c5a99b6a84f2576d13d1f23825a18fc6e249777 Mon Sep 17 00:00:00 2001
From: lcnr <rust@lcnr.de>
Date: Mon, 18 Mar 2024 16:37:47 +0100
Subject: [PATCH] improve comments
---
compiler/rustc_type_ir/src/predicate_kind.rs | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
diff --git a/compiler/rustc_type_ir/src/predicate_kind.rs b/compiler/rustc_type_ir/src/predicate_kind.rs
index a0759f7df7f..112f617fe16 100644
--- a/compiler/rustc_type_ir/src/predicate_kind.rs
+++ b/compiler/rustc_type_ir/src/predicate_kind.rs
@@ -148,19 +148,20 @@ pub enum PredicateKind<I: Interner> {
/// Used for coherence to mark opaque types as possibly equal to each other but ambiguous.
Ambiguous,
- /// The alias normalizes to `term`. Unlike `Projection`, this always fails if the alias
- /// cannot be normalized in the current context.
+ /// This should only be used inside of the new solver for `AliasRelate` and expects
+ /// the `term` to be an unconstrained inference variable.
///
- /// `Projection(<T as Trait>::Assoc, ?x)` results in `?x == <T as Trait>::Assoc` while
- /// `NormalizesTo(<T as Trait>::Assoc, ?x)` results in `NoSolution`.
- ///
- /// Only used in the new solver.
+ /// The alias normalizes to `term`. Unlike `Projection`, this always fails if the
+ /// alias cannot be normalized in the current context. For the rigid alias
+ /// `T as Trait>::Assoc`, `Projection(<T as Trait>::Assoc, ?x)` constrains `?x`
+ /// to `<T as Trait>::Assoc` while `NormalizesTo(<T as Trait>::Assoc, ?x)`
+ /// results in `NoSolution`.
NormalizesTo(I::NormalizesTo),
/// Separate from `ClauseKind::Projection` which is used for normalization in new solver.
/// This predicate requires two terms to be equal to eachother.
///
- /// Only used for new solver
+ /// Only used for new solver.
AliasRelate(I::Term, I::Term, AliasRelationDirection),
}