+lookup_global :: TcEnv -> Name -> Maybe TyThing
+ -- Try the global envt and then the global symbol table
+lookup_global env name
+ = case lookupNameEnv (tcGEnv env) name of
+ Just thing -> Just thing
+ Nothing -> tcGST env name
+
+lookup_local :: TcEnv -> Name -> Maybe TcTyThing
+ -- Try the local envt and then try the global
+lookup_local env name
+ = case lookupNameEnv (tcLEnv env) name of
+ Just thing -> Just thing
+ Nothing -> case lookup_global env name of
+ Just thing -> Just (AGlobal thing)
+ Nothing -> Nothing
+\end{code}
+
+\begin{code}
+type RecTcEnv = TcEnv
+-- This environment is used for getting the 'right' IdInfo
+-- on imported things and for looking up Ids in unfoldings
+-- The environment doesn't have any local Ids in it
+
+tcAddImportedIdInfo :: RecTcEnv -> Id -> Id
+tcAddImportedIdInfo env id
+ = id `lazySetIdInfo` new_info
+ -- The Id must be returned without a data dependency on maybe_id
+ where
+ new_info = case tcLookupRecId_maybe env (idName id) of
+ Nothing -> pprTrace "tcAddIdInfo" (ppr id) vanillaIdInfo
+ Just imported_id -> idInfo imported_id
+ -- ToDo: could check that types are the same
+
+tcLookupRecId_maybe :: RecTcEnv -> Name -> Maybe Id
+tcLookupRecId_maybe env name = case lookup_global env name of
+ Just (AnId id) -> Just id
+ other -> Nothing
+
+tcLookupRecId :: RecTcEnv -> Name -> Id
+tcLookupRecId env name = case lookup_global env name of
+ Just (AnId id) -> id
+ Nothing -> pprPanic "tcLookupRecId" (ppr name)
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Making new Ids}
+%* *
+%************************************************************************
+
+Constructing new Ids
+
+\begin{code}
+newLocalId :: OccName -> TcType -> SrcLoc -> NF_TcM TcId
+newLocalId name ty loc
+ = tcGetUnique `thenNF_Tc` \ uniq ->
+ returnNF_Tc (mkUserLocal name uniq ty loc)
+
+newSpecPragmaId :: Name -> TcType -> NF_TcM TcId
+newSpecPragmaId name ty
+ = tcGetUnique `thenNF_Tc` \ uniq ->
+ returnNF_Tc (mkSpecPragmaId (nameOccName name) uniq ty (getSrcLoc name))
+\end{code}
+
+Make a name for the dict fun for an instance decl.
+It's a *local* name for the moment. The CoreTidy pass
+will globalise it.
+
+\begin{code}
+newDFunName :: Class -> [Type] -> SrcLoc -> NF_TcM Name
+newDFunName clas (ty:_) loc
+ = tcGetUnique `thenNF_Tc` \ uniq ->
+ returnNF_Tc (mkLocalName uniq (mkDFunOcc dfun_string) loc)
+ where
+ -- Any string that is somewhat unique will do
+ dfun_string = occNameString (getOccName clas) ++ occNameString (getDFunTyKey ty)
+
+newDFunName clas [] loc = pprPanic "newDFunName" (ppr clas <+> ppr loc)
+\end{code}
+
+\begin{code}
+isLocalThing :: NamedThing a => Module -> a -> Bool
+isLocalThing mod thing = nameIsLocalOrFrom mod (getName thing)
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{The global environment}
+%* *
+%************************************************************************