X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FdeSugar%2FDsMonad.lhs;h=83a5d212ae84eb720408de651dc585db50676ba0;hb=aedb94f5f220b5e442b23ecc445fd38c8d9b6ba0;hp=145ba9e37129b11d06594d343a6ec23e94c4ec83;hpb=3b2cd7b311da1e7056ef66b42efc2571add5a8aa;p=ghc-hetmet.git

diff --git a/compiler/deSugar/DsMonad.lhs b/compiler/deSugar/DsMonad.lhs
index 145ba9e..83a5d21 100644
--- a/compiler/deSugar/DsMonad.lhs
+++ b/compiler/deSugar/DsMonad.lhs
@@ -14,7 +14,7 @@ module DsMonad (
 
 	newLocalName,
 	duplicateLocalDs, newSysLocalDs, newSysLocalsDs, newUniqueId,
-	newFailLocalDs,
+	newFailLocalDs, newPredVarDs,
 	getSrcSpanDs, putSrcSpanDs,
 	getModuleDs,
 	newUnique, 
@@ -224,12 +224,22 @@ newUniqueId :: Name -> Type -> DsM Id
 newUniqueId id = mkSysLocalM (occNameFS (nameOccName id))
 
 duplicateLocalDs :: Id -> DsM Id
-duplicateLocalDs old_local = do
-    uniq <- newUnique
-    return (setIdUnique old_local uniq)
-
+duplicateLocalDs old_local 
+  = do	{ uniq <- newUnique
+	; return (setIdUnique old_local uniq) }
+
+newPredVarDs :: PredType -> DsM Var
+newPredVarDs pred
+ | isEqPred pred
+ = do { uniq <- newUnique; 
+      ; let name = mkSystemName uniq (mkOccNameFS tcName (fsLit "co"))
+	    kind = mkPredTy pred
+      ; return (mkCoVar name kind) }
+ | otherwise
+ = newSysLocalDs (mkPredTy pred)
+ 
 newSysLocalDs, newFailLocalDs :: Type -> DsM Id
-newSysLocalDs = mkSysLocalM (fsLit "ds")
+newSysLocalDs  = mkSysLocalM (fsLit "ds")
 newFailLocalDs = mkSysLocalM (fsLit "fail")
 
 newSysLocalsDs :: [Type] -> DsM [Id]