From e567cb5a3ee0fd01c3a96d9688b1ae54e9b541e7 Mon Sep 17 00:00:00 2001
From: Sean Bowe <ewillbefull@gmail.com>
Date: Wed, 16 Sep 2015 15:07:35 -0600
Subject: [PATCH] Clarify behavior of Sub/Equate type relationships.

---
 src/librustc/middle/infer/equate.rs | 1 +
 src/librustc/middle/infer/sub.rs    | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/librustc/middle/infer/equate.rs b/src/librustc/middle/infer/equate.rs
index 6c6b1358a15c9..8a01f78a7580c 100644
--- a/src/librustc/middle/infer/equate.rs
+++ b/src/librustc/middle/infer/equate.rs
@@ -17,6 +17,7 @@ use middle::ty::{self, Ty};
 use middle::ty::TyVar;
 use middle::ty_relate::{Relate, RelateResult, TypeRelation};
 
+/// Ensures `a` is made equal to `b`. Returns `a` on success.
 pub struct Equate<'a, 'tcx: 'a> {
     fields: CombineFields<'a, 'tcx>
 }
diff --git a/src/librustc/middle/infer/sub.rs b/src/librustc/middle/infer/sub.rs
index 7ff778d470fbf..7d0cc648fd46f 100644
--- a/src/librustc/middle/infer/sub.rs
+++ b/src/librustc/middle/infer/sub.rs
@@ -18,7 +18,7 @@ use middle::ty::TyVar;
 use middle::ty_relate::{Cause, Relate, RelateResult, TypeRelation};
 use std::mem;
 
-/// "Greatest lower bound" (common subtype)
+/// Ensures `a` is made a subtype of `b`. Returns `a` on success.
 pub struct Sub<'a, 'tcx: 'a> {
     fields: CombineFields<'a, 'tcx>,
 }