X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcType.lhs;h=24cf3f8722b911aa6a2e6d514c6293731b32db21;hb=a13551ce57c67a333f41f0a6fe7e05a09d0c3614;hp=bfff2c8e552a5b9b67c969dff19c4f5ac3294dc8;hpb=ad17cf6e34b6ab03f19914e7d2c1262b073db3fa;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcType.lhs b/compiler/typecheck/TcType.lhs
index bfff2c8..24cf3f8 100644
--- a/compiler/typecheck/TcType.lhs
+++ b/compiler/typecheck/TcType.lhs
@@ -55,7 +55,7 @@ module TcType (
   eqKind, 
   isSigmaTy, isOverloadedTy, isRigidTy, isBoxyTy,
   isDoubleTy, isFloatTy, isIntTy, isStringTy,
-  isIntegerTy, isBoolTy, isUnitTy,
+  isIntegerTy, isBoolTy, isUnitTy, isCharTy,
   isTauTy, isTauTyCon, tcIsTyVarTy, tcIsForAllTy, 
 
   ---------------------------------
@@ -323,6 +323,9 @@ data SkolemInfo
   | GenSkol [TcTyVar]	-- Bound when doing a subsumption check for 
 	    TcType	-- 	(forall tvs. ty)
 
+  | RuntimeUnkSkol      -- a type variable used to represent an unknown
+                        -- runtime type (used in the GHCi debugger)
+
   | UnkSkol		-- Unhelpful info (until I improve it)
 
 -------------------------------------
@@ -439,16 +442,18 @@ pprSkolTvBinding :: TcTyVar -> SDoc
 -- or nothing if we don't have anything useful to say
 pprSkolTvBinding tv
   = ASSERT ( isTcTyVar tv )
-    ppr_details (tcTyVarDetails tv)
+    quotes (ppr tv) <+> ppr_details (tcTyVarDetails tv)
   where
-    ppr_details (MetaTv TauTv _)   = quotes (ppr tv) <+> ptext SLIT("is a meta type variable")
-    ppr_details (MetaTv BoxTv _)   = quotes (ppr tv) <+> ptext SLIT("is a boxy type variable")
+    ppr_details (MetaTv TauTv _)   	= ptext SLIT("is a meta type variable")
+    ppr_details (MetaTv BoxTv _)   	= ptext SLIT("is a boxy type variable")
     ppr_details (MetaTv (SigTv info) _) = ppr_skol info
     ppr_details (SkolemTv info)		= ppr_skol info
 
-    ppr_skol UnkSkol = empty	-- Unhelpful; omit
-    ppr_skol info    = quotes (ppr tv) <+> ptext SLIT("is bound by") 
-			<+> sep [pprSkolInfo info, nest 2 (ptext SLIT("at") <+> ppr (getSrcLoc tv))]
+    ppr_skol UnkSkol	    = empty	-- Unhelpful; omit
+    ppr_skol RuntimeUnkSkol = ptext SLIT("is an unknown runtime type")
+    ppr_skol info           = sep [ptext SLIT("is a rigid type variable bound by"),
+				   sep [pprSkolInfo info, 
+					 nest 2 (ptext SLIT("at") <+> ppr (getSrcLoc tv))]]
  
 pprSkolInfo :: SkolemInfo -> SDoc
 pprSkolInfo (SigSkol ctxt)   = pprUserTypeCtxt ctxt
@@ -465,6 +470,7 @@ pprSkolInfo (GenSkol tvs ty) = sep [ptext SLIT("the polymorphic type"),
 -- For type variables the others are dealt with by pprSkolTvBinding.  
 -- For Insts, these cases should not happen
 pprSkolInfo UnkSkol = panic "UnkSkol"
+pprSkolInfo RuntimeUnkSkol = panic "RuntimeUnkSkol"
 
 instance Outputable MetaDetails where
   ppr Flexi 	    = ptext SLIT("Flexi")
@@ -710,9 +716,16 @@ tcSplitFunTys ty = case tcSplitFunTy_maybe ty of
 					  (args,res') = tcSplitFunTys res
 
 tcSplitFunTy_maybe :: Type -> Maybe (Type, Type)
-tcSplitFunTy_maybe ty | Just ty' <- tcView ty = tcSplitFunTy_maybe ty'
-tcSplitFunTy_maybe (FunTy arg res)  = Just (arg, res)
-tcSplitFunTy_maybe other	    = Nothing
+tcSplitFunTy_maybe ty | Just ty' <- tcView ty           = tcSplitFunTy_maybe ty'
+tcSplitFunTy_maybe (FunTy arg res) | not (isPredTy arg) = Just (arg, res)
+tcSplitFunTy_maybe other	  			= Nothing
+	-- Note the (not (isPredTy arg)) guard
+	-- Consider	(?x::Int) => Bool
+	-- We don't want to treat this as a function type!
+	-- A concrete example is test tc230:
+	--	f :: () -> (?p :: ()) => () -> ()
+	--
+	--	g = f () ()
 
 tcSplitFunTysN
 	:: TcRhoType 
@@ -890,11 +903,11 @@ dataConsStupidTheta (con1:cons)
   = nubBy tcEqPred all_preds
   where
     all_preds 	  = dataConStupidTheta con1 ++ other_stupids
-    res_tys1  	  = dataConResTys con1
-    tvs1      	  = tyVarsOfTypes res_tys1
+    res_ty1       = dataConOrigResTy con1
     other_stupids = [ substPred subst pred
 		    | con <- cons
-		    , let Just subst = tcMatchTys tvs1 res_tys1 (dataConResTys con)
+		    , let (tvs, _, _, res_ty) = dataConSig con
+			  Just subst = tcMatchTy (mkVarSet tvs) res_ty res_ty1
 		    , pred <- dataConStupidTheta con ]
 dataConsStupidTheta [] = panic "dataConsStupidTheta"
 \end{code}
@@ -937,6 +950,12 @@ isIntegerTy    = is_tc integerTyConKey
 isIntTy        = is_tc intTyConKey
 isBoolTy       = is_tc boolTyConKey
 isUnitTy       = is_tc unitTyConKey
+isCharTy       = is_tc charTyConKey
+
+isStringTy ty
+  = case tcSplitTyConApp_maybe ty of
+      Just (tc, [arg_ty]) -> tc == listTyCon && isCharTy arg_ty
+      other		  -> False
 
 is_tc :: Unique -> Type -> Bool
 -- Newtypes are opaque to this
@@ -1130,18 +1149,10 @@ isFFIDotnetTy :: DynFlags -> Type -> Bool
 isFFIDotnetTy dflags ty
   = checkRepTyCon (\ tc -> (legalFIResultTyCon dflags tc || 
 			   isFFIDotnetObjTy ty || isStringTy ty)) ty
+	-- NB: isStringTy used to look through newtypes, but
+	--     it no longer does so.  May need to adjust isFFIDotNetTy
+	--     if we do want to look through newtypes.
 
--- Support String as an argument or result from a .NET FFI call.
-isStringTy ty = 
-  case tcSplitTyConApp_maybe (repType ty) of
-    Just (tc, [arg_ty])
-      | tc == listTyCon ->
-        case tcSplitTyConApp_maybe (repType arg_ty) of
-	  Just (cc,[]) -> cc == charTyCon
-	  _ -> False
-    _ -> False
-
--- Support String as an argument or result from a .NET FFI call.
 isFFIDotnetObjTy ty = 
   let
    (_, t_ty) = tcSplitForAllTys ty