From: sof <unknown>
Date: Sat, 5 Jul 1997 02:20:43 +0000 (+0000)
Subject: [project @ 1997-07-05 02:19:07 by sof]
X-Git-Tag: Approximately_1000_patches_recorded~269
X-Git-Url: http://git.megacz.com/?a=commitdiff_plain;h=3a3a71aa1e4a09822988070228ff8a8e77e9a1ab;p=ghc-hetmet.git

[project @ 1997-07-05 02:19:07 by sof]
---

diff --git a/ghc/compiler/typecheck/TcType.hi-boot b/ghc/compiler/typecheck/TcType.hi-boot
index a540f45..49e5cd6 100644
--- a/ghc/compiler/typecheck/TcType.hi-boot
+++ b/ghc/compiler/typecheck/TcType.hi-boot
@@ -1,6 +1,6 @@
 _interface_ TcType 1
 _exports_
-TcType TcMaybe;
+TcType TcMaybe TcTyVarSet;
 _declarations_
 1 data TcMaybe a;
-
+1 type TcTyVarSet a = TyVar.GenTyVarSet (ArrBase.MutableVar a (TcMaybe a));
diff --git a/ghc/compiler/typecheck/TcType.lhs b/ghc/compiler/typecheck/TcType.lhs
index 7902ace..b6c2362 100644
--- a/ghc/compiler/typecheck/TcType.lhs
+++ b/ghc/compiler/typecheck/TcType.lhs
@@ -178,7 +178,10 @@ inst_tyvars initial_cts tyvars
 inst_tyvar initial_cts (TyVar _ kind name _) 
   = tcGetUnique 		`thenNF_Tc` \ uniq ->
     tcNewMutVar initial_cts	`thenNF_Tc` \ box ->
-    returnNF_Tc (TyVar uniq kind name box)
+    returnNF_Tc (TyVar uniq kind Nothing box)
+	-- The "Nothing" means that it'll always print with its 
+	-- unique (or something similar).  If we leave the original (Just Name)
+	-- in there then error messages will say "can't match (T a) against (T a)"
 \end{code}
 
 @tcInstType@ and @tcInstSigType@ both create a fresh instance of a