X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypes%2FUnify.lhs;h=2f2cfb892734c4c31b990705989bd2916492f72f;hp=de5ac49c2dae762788fda1596c76415eadaa3748;hb=a40f2735958055f7ff94e5df73e710044aa63b2c;hpb=71de34ed68265e4f950bd2d43d1f2e955de8b959

diff --git a/compiler/types/Unify.lhs b/compiler/types/Unify.lhs
index de5ac49..2f2cfb8 100644
--- a/compiler/types/Unify.lhs
+++ b/compiler/types/Unify.lhs
@@ -380,7 +380,7 @@ dataConCannotMatch tys con
 \begin{code}
 tcUnifyTys :: (TyVar -> BindFlag)
 	   -> [Type] -> [Type]
-	   -> Maybe TvSubst	-- A regular one-shot substitution
+	   -> Maybe TvSubst	-- A regular one-shot (idempotent) substitution
 -- The two types may have common type variables, and indeed do so in the
 -- second call to tcUnifyTys in FunDeps.checkClsFD
 --