X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcEnv.lhs;h=6e5f381d1cf93fe72681314ab1ed241e4d473838;hb=a1579a34bba86590e3656e5c7e88a78a9fb2f584;hp=1d093e2e7c4d1aa2a2760c25def972c16e72be7a;hpb=15cb792d18b1094e98c035dca6ecec5dad516056;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcEnv.lhs b/compiler/typecheck/TcEnv.lhs
index 1d093e2..6e5f381 100644
--- a/compiler/typecheck/TcEnv.lhs
+++ b/compiler/typecheck/TcEnv.lhs
@@ -38,7 +38,7 @@ module TcEnv(
 	topIdLvl, 
 
 	-- New Ids
-	newLocalName, newDFunName
+	newLocalName, newDFunName, newFamInstTyConName
   ) where
 
 #include "HsVersions.h"
@@ -50,8 +50,8 @@ import TcIface		( tcImportDecl )
 import IfaceEnv		( newGlobalBinder )
 import TcRnMonad
 import TcMType		( zonkTcType, zonkTcTyVarsAndFV )
-import TcType		( Type, TcKind, TcTyVar, TcTyVarSet, TcType, 
-			  substTy, tyVarsOfType, tcTyVarsOfTypes, mkTyConApp,
+import TcType		( Type, TcKind, TcTyVar, TcTyVarSet, TcType, PredType,
+			  tyVarsOfType, tcTyVarsOfTypes, mkTyConApp,
 			  getDFunTyKey, tcTyConAppTyCon, tcGetTyVar, mkTyVarTy,
 			  tidyOpenType, isRefineableTy
 			)
@@ -66,11 +66,13 @@ import InstEnv		( Instance, DFunId, instanceDFunId, instanceHead )
 import DataCon		( DataCon )
 import TyCon		( TyCon )
 import Class		( Class )
-import Name		( Name, NamedThing(..), getSrcLoc, nameModule )
+import Name		( Name, NamedThing(..), getSrcLoc, nameModule,
+			  nameOccName )
 import PrelNames	( thFAKE )
 import NameEnv
-import OccName		( mkDFunOcc, occNameString )
-import HscTypes		( extendTypeEnvList, lookupType, TyThing(..), ExternalPackageState(..) )
+import OccName		( mkDFunOcc, occNameString, mkInstTyTcOcc )
+import HscTypes		( extendTypeEnvList, lookupType, TyThing(..),
+			  ExternalPackageState(..) )
 import SrcLoc		( SrcLoc, Located(..) )
 import Outputable
 \end{code}
@@ -360,7 +362,7 @@ findGlobals tvs tidy_env
 	  Just d  -> go tidy_env1 (d:acc) things
 	  Nothing -> go tidy_env1 acc     things
 
-    ignore_it ty = not (tvs `intersectsVarSet` tyVarsOfType ty)
+    ignore_it ty = tvs `disjointVarSet` tyVarsOfType ty
 
 -----------------------
 find_thing ignore_it tidy_env (ATcId { tct_id = id })
@@ -565,20 +567,26 @@ data InstBindings
 	[LSig Name]		-- User pragmas recorded for generating 
 				-- specialised instances
 
-  | NewTypeDerived 		
-        TyCon                   -- tycon for the newtype
-                                -- Used for deriving instances of newtypes, where the
-	[Type]			-- witness dictionary is identical to the argument 
-				-- dictionary.  Hence no bindings, no pragmas
-	-- The [Type] are the representation types
-	-- See notes in TcDeriv
+  | NewTypeDerived              -- Used for deriving instances of newtypes, where the
+				-- witness dictionary is identical to the argument 
+				-- dictionary.  Hence no bindings, no pragmas.
+	(Maybe [PredType])
+		-- Nothing      => The newtype-derived instance involves type variables,
+		--	           and the dfun has a type like df :: forall a. Eq a => Eq (T a)
+		-- Just (r:scs) => The newtype-defined instance has no type variables
+		--		   so the dfun is just a constant, df :: Eq T
+		-- 		   In this case we need to know waht the rep dict, r, and the 
+		--		   superclasses, scs, are.  (In the Nothing case these are in the
+		--		   dict fun's type.)
+		--		   Invariant: these PredTypes have no free variables
+		-- NB: In both cases, the representation dict is the *first* dict.
 
 pprInstInfo info = vcat [ptext SLIT("InstInfo:") <+> ppr (idType (iDFunId info))]
 
 pprInstInfoDetails info = pprInstInfo info $$ nest 2 (details (iBinds info))
   where
     details (VanillaInst b _)  = pprLHsBinds b
-    details (NewTypeDerived _  _) = text "Derived from the representation type"
+    details (NewTypeDerived _) = text "Derived from the representation type"
 
 simpleInstInfoClsTy :: InstInfo -> (Class, Type)
 simpleInstInfoClsTy info = case instanceHead (iSpec info) of
@@ -611,6 +619,19 @@ newDFunName clas (ty:_) loc
 newDFunName clas [] loc = pprPanic "newDFunName" (ppr clas <+> ppr loc)
 \end{code}
 
+Make a name for the representation tycon of a data/newtype instance.  It's an
+*external* name, like otber top-level names, and hence must be made with
+newGlobalBinder.
+
+\begin{code}
+newFamInstTyConName :: Name -> SrcLoc -> TcM Name
+newFamInstTyConName tc_name loc
+  = do	{ index <- nextDFunIndex
+	; mod   <- getModule
+	; let occ = nameOccName tc_name
+	; newGlobalBinder mod (mkInstTyTcOcc index occ) Nothing loc }
+\end{code}
+
 
 %************************************************************************
 %*									*