- (n,pn) `beats` (m,pm) = n==m && pn `hasBetterProv` pm
-
- is_duplicate :: Provenance -> (Name,Provenance) -> Bool
- is_duplicate (n1,LocalDef _) (n2,LocalDef _) = False
- is_duplicate n1 n2 = n1 == n2
-\end{code}
-
-We treat two bindings of a locally-defined name as a duplicate,
-because they might be two separate, local defns and we want to report
-and error for that, {\em not} eliminate a duplicate.
-
-On the other hand, if you import the same name from two different
-import statements, we {\em do} want to eliminate the duplicate, not report
-an error.
-
-If a module imports itself then there might be a local defn and an imported
-defn of the same name; in this case the names will compare as equal, but
-will still have different provenances.
-
-
-@unQualInScope@ returns a function that takes a @Name@ and tells whether
-its unqualified name is in scope. This is put as a boolean flag in
-the @Name@'s provenance to guide whether or not to print the name qualified
-in error messages.
-
-\begin{code}
-unQualInScope :: GlobalRdrEnv -> Name -> Bool
-unQualInScope env
- = lookup
- where
- lookup name = case lookupRdrEnv env (mkRdrUnqual (nameOccName name)) of
- Just [(name',_)] -> name == name'
- other -> False
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{Avails}
-%* *
-%************************************************************************
-
-\begin{code}
-plusAvail (Avail n1) (Avail n2) = Avail n1
-plusAvail (AvailTC n1 ns1) (AvailTC n2 ns2) = AvailTC n2 (nub (ns1 ++ ns2))
--- Added SOF 4/97
-#ifdef DEBUG
-plusAvail a1 a2 = pprPanic "RnEnv.plusAvail" (hsep [pprAvail a1,pprAvail a2])
-#endif
-
-addAvail :: AvailEnv -> AvailInfo -> AvailEnv
-addAvail avails avail = extendNameEnv_C plusAvail avails (availName avail) avail
-
-emptyAvailEnv = emptyNameEnv
-unitAvailEnv :: AvailInfo -> AvailEnv
-unitAvailEnv a = unitNameEnv (availName a) a
-
-plusAvailEnv :: AvailEnv -> AvailEnv -> AvailEnv
-plusAvailEnv = plusNameEnv_C plusAvail
-
-availEnvElts = nameEnvElts
-
-addAvailToNameSet :: NameSet -> AvailInfo -> NameSet
-addAvailToNameSet names avail = addListToNameSet names (availNames avail)
-
-availsToNameSet :: [AvailInfo] -> NameSet
-availsToNameSet avails = foldl addAvailToNameSet emptyNameSet avails
-
-availName :: GenAvailInfo name -> name
-availName (Avail n) = n
-availName (AvailTC n _) = n
-
-availNames :: GenAvailInfo name -> [name]
-availNames (Avail n) = [n]
-availNames (AvailTC n ns) = ns
-
-addSysAvails :: AvailInfo -> [Name] -> AvailInfo
-addSysAvails avail [] = avail
-addSysAvails (AvailTC n ns) sys = AvailTC n (sys ++ ns)
-
-rdrAvailInfo :: AvailInfo -> RdrAvailInfo
--- Used when building the avails we are going to put in an interface file
--- We sort the components to reduce needless wobbling of interfaces
-rdrAvailInfo (Avail n) = Avail (nameOccName n)
-rdrAvailInfo (AvailTC n ns) = AvailTC (nameOccName n) (sortLt (<) (map nameOccName ns))
-
-filterAvail :: RdrNameIE -- Wanted
- -> AvailInfo -- Available
- -> Maybe AvailInfo -- Resulting available;
- -- Nothing if (any of the) wanted stuff isn't there
-
-filterAvail ie@(IEThingWith want wants) avail@(AvailTC n ns)
- | sub_names_ok = Just (AvailTC n (filter is_wanted ns))
- | otherwise = Nothing
- where
- is_wanted name = nameOccName name `elem` wanted_occs
- sub_names_ok = all (`elem` avail_occs) wanted_occs
- avail_occs = map nameOccName ns
- wanted_occs = map rdrNameOcc (want:wants)
-
-filterAvail (IEThingAbs _) (AvailTC n ns) = ASSERT( n `elem` ns )
- Just (AvailTC n [n])
-
-filterAvail (IEThingAbs _) avail@(Avail n) = Just avail -- Type synonyms
-
-filterAvail (IEVar _) avail@(Avail n) = Just avail
-filterAvail (IEVar v) avail@(AvailTC n ns) = Just (AvailTC n (filter wanted ns))
- where
- wanted n = nameOccName n == occ
- occ = rdrNameOcc v
- -- The second equation happens if we import a class op, thus
- -- import A( op )
- -- where op is a class operation
-
-filterAvail (IEThingAll _) avail@(AvailTC _ _) = Just avail
- -- We don't complain even if the IE says T(..), but
- -- no constrs/class ops of T are available
- -- Instead that's caught with a warning by the caller
-
-filterAvail ie avail = Nothing
-
-pprAvail :: AvailInfo -> SDoc
-pprAvail (AvailTC n ns) = ppr n <> case filter (/= n) ns of
- [] -> empty
- ns' -> parens (hsep (punctuate comma (map ppr ns')))
-
-pprAvail (Avail n) = ppr n