X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcType.lhs;h=dad167cabdd5d1184e918d8081a46fba27205f21;hb=7854ec4b11e117f8514553890851d14a66690fbb;hp=ce42def248d98097a0fa881eba0308bc4511ab2a;hpb=d436c70d43fb905c63220040168295e473f4b90a;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcType.lhs b/compiler/typecheck/TcType.lhs
index ce42def..dad167c 100644
--- a/compiler/typecheck/TcType.lhs
+++ b/compiler/typecheck/TcType.lhs
@@ -92,7 +92,6 @@ module TcType (
   isFFITy,	       -- :: Type -> Bool
   isFunPtrTy,          -- :: Type -> Bool
   tcSplitIOType_maybe, -- :: Type -> Maybe Type  
-  toDNType,            -- :: Type -> DNType
 
   --------------------------------
   -- Rexported from Type
@@ -644,7 +643,6 @@ getDFunTyKey ty		     = pprPanic "getDFunTyKey" (pprType ty)
 These tcSplit functions are like their non-Tc analogues, but
 	a) they do not look through newtypes
 	b) they do not look through PredTys
-	c) [future] they ignore usage-type annotations
 
 However, they are non-monadic and do not follow through mutable type
 variables.  It's up to you to make sure this doesn't matter.
@@ -805,18 +803,29 @@ tcIsTyVarTy :: Type -> Bool
 tcIsTyVarTy ty = maybeToBool (tcGetTyVar_maybe ty)
 
 -----------------------
-tcSplitDFunTy :: Type -> ([TyVar], [PredType], Class, [Type])
+tcSplitDFunTy :: Type -> ([TyVar], Class, [Type])
 -- Split the type of a dictionary function
+-- We don't use tcSplitSigmaTy,  because a DFun may (with NDP)
+-- have non-Pred arguments, such as
+--     df :: forall m. (forall b. Eq b => Eq (m b)) -> C m
 tcSplitDFunTy ty 
-  = case tcSplitSigmaTy ty   of { (tvs, theta, tau) ->
-    case tcSplitDFunHead tau of { (clas, tys) -> 
-    (tvs, theta, clas, tys) }}
+  = case tcSplitForAllTys ty                 of { (tvs, rho)  ->
+    case tcSplitDFunHead (drop_pred_tys rho) of { (clas, tys) -> 
+    (tvs, clas, tys) }}
+  where
+    -- Discard the context of the dfun.  This can be a mix of
+    -- coercion and class constraints; or (in the general NDP case)
+    -- some other function argument
+    drop_pred_tys ty | Just ty' <- tcView ty = drop_pred_tys ty'
+    drop_pred_tys (ForAllTy tv ty) = ASSERT( isCoVar tv ) drop_pred_tys ty
+    drop_pred_tys (FunTy _ ty)     = drop_pred_tys ty
+    drop_pred_tys ty               = ty
 
 tcSplitDFunHead :: Type -> (Class, [Type])
 tcSplitDFunHead tau  
   = case tcSplitPredTy_maybe tau of 
 	Just (ClassP clas tys) -> (clas, tys)
-	_ -> panic "tcSplitDFunHead"
+	_ -> pprPanic "tcSplitDFunHead" (ppr tau)
 
 tcInstHeadTyNotSynonym :: Type -> Bool
 -- Used in Haskell-98 mode, for the argument types of an instance head
@@ -1258,39 +1267,6 @@ isFFIDotnetObjTy ty
 isFunPtrTy :: Type -> Bool
 isFunPtrTy = checkRepTyConKey [funPtrTyConKey]
 
-toDNType :: Type -> DNType
-toDNType ty
-  | isStringTy ty = DNString
-  | isFFIDotnetObjTy ty = DNObject
-  | Just (tc,argTys) <- tcSplitTyConApp_maybe ty 
-  =  case lookup (getUnique tc) dn_assoc of
-       Just x  -> x
-       Nothing 
-         | tc `hasKey` ioTyConKey -> toDNType (head argTys)
-	 | otherwise -> pprPanic ("toDNType: unsupported .NET type") 
-			  (pprType ty <+> parens (hcat (map pprType argTys)) <+> ppr tc)
-  | otherwise = panic "toDNType"	-- Is this right?
-    where
-      dn_assoc :: [ (Unique, DNType) ]
-      dn_assoc = [ (unitTyConKey,   DNUnit)
-      		 , (intTyConKey,    DNInt)
-      	         , (int8TyConKey,   DNInt8)
-		 , (int16TyConKey,  DNInt16)
-		 , (int32TyConKey,  DNInt32)
-		 , (int64TyConKey,  DNInt64)
-		 , (wordTyConKey,   DNInt)
-		 , (word8TyConKey,  DNWord8)
-		 , (word16TyConKey, DNWord16)
-		 , (word32TyConKey, DNWord32)
-		 , (word64TyConKey, DNWord64)
-		 , (floatTyConKey,  DNFloat)
-		 , (doubleTyConKey, DNDouble)
-		 , (ptrTyConKey,    DNPtr)
-		 , (funPtrTyConKey, DNPtr)
-		 , (charTyConKey,   DNChar)
-		 , (boolTyConKey,   DNBool)
-		 ]
-
 checkRepTyCon :: (TyCon -> Bool) -> Type -> Bool
 -- Look through newtypes, but *not* foralls
 -- Should work even for recursive newtypes