X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;ds=sidebyside;f=compiler%2Ftypecheck%2FTcEnv.lhs;h=59d60ebf599d5cc6f480b5e83b77981e96f634ee;hb=b00b5bc04ff36a551552470060064f0b7d84ca30;hp=1d093e2e7c4d1aa2a2760c25def972c16e72be7a;hpb=15cb792d18b1094e98c035dca6ecec5dad516056;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcEnv.lhs b/compiler/typecheck/TcEnv.lhs
index 1d093e2..59d60eb 100644
--- a/compiler/typecheck/TcEnv.lhs
+++ b/compiler/typecheck/TcEnv.lhs
@@ -38,20 +38,20 @@ module TcEnv(
 	topIdLvl, 
 
 	-- New Ids
-	newLocalName, newDFunName
+	newLocalName, newDFunName, newFamInstTyConName
   ) where
 
 #include "HsVersions.h"
 
 import HsSyn		( LRuleDecl, LHsBinds, LSig, 
 			  LHsTyVarBndr, HsTyVarBndr(..), pprLHsBinds,
-		 	  idCoercion, (<.>) )
+		 	  idHsWrapper, (<.>) )
 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 +66,12 @@ 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_maybe, 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}
@@ -112,13 +113,15 @@ tcLookupGlobal name
 	    Nothing    -> do
 
 		-- Should it have been in the local envt?
-	{ let mod = nameModule name
-	; if mod == tcg_mod env || mod == thFAKE then
-		notFound name	-- It should be local, so panic
-				-- The thFAKE possibility is because it
-				-- might be in a declaration bracket
-	  else
-		tcImportDecl name	-- Go find it in an interface
+	{ case nameModule_maybe name of
+		Nothing -> notFound name	-- Internal names can happen in GHCi
+
+		Just mod | mod == tcg_mod env 	-- Names from this module 
+			 -> notFound name	-- should be in tcg_type_env
+			 | mod == thFAKE	-- Names bound in TH declaration brackets
+			 -> notFound name	-- should be in tcg_env
+			 | otherwise
+		         -> tcImportDecl name	-- Go find it in an interface
 	}}}}}
 
 tcLookupField :: Name -> TcM Id		-- Returns the selector Id
@@ -324,7 +327,7 @@ tcExtendIdEnv2 names_w_ids thing_inside
 					       tct_level = th_lvl,
 					       tct_type = id_ty, 
 					       tct_co = if isRefineableTy id_ty 
-							then Just idCoercion
+							then Just idHsWrapper
 							else Nothing })
 			      | (name,id) <- names_w_ids, let id_ty = idType id]
 	le'		    = extendNameEnvList (tcl_env env) extra_env
@@ -360,7 +363,7 @@ 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 +568,26 @@ 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
@@ -606,11 +615,24 @@ newDFunName clas (ty:_) loc
 			    occNameString (getDFunTyKey ty)
 	      dfun_occ = mkDFunOcc info_string is_boot index
 
-	; newGlobalBinder mod dfun_occ Nothing loc }
+	; newGlobalBinder mod dfun_occ 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) loc }
+\end{code}
+
 
 %************************************************************************
 %*									*