import NameSet
import OccName ( srcDataName, pprNonVarNameSpace,
occNameSpace,
- OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv,
- extendOccEnv )
+ OccEnv, mkOccEnv, mkOccEnv_C, lookupOccEnv,
+ emptyOccEnv, extendOccEnv )
import HscTypes ( GenAvailInfo(..), AvailInfo, availNames, availName,
HomePackageTable, PackageIfaceTable,
mkPrintUnqualified, availsToNameSet,
import DriverPhases ( isHsBoot )
import Util
import ListSetOps
-import Data.List ( partition, concatMap )
+import Data.List ( partition, concatMap, (\\) )
import IO ( openFile, IOMode(..) )
import Monad ( when )
\end{code}
-- filter the imports according to the import declaration
(new_imp_details, gbl_env) <-
- filterImports iface imp_spec imp_details total_avails
+ filterImports2 iface imp_spec imp_details total_avails
dflags <- getDOpts
gres | want_hiding = gresFromAvails hiding_prov pruned_avails
| otherwise = concatMap (gresFromIE decl_spec) items2
+ traceRn (ppr $ all_avails)
+ traceRn (ppr $ occ_env)
+ traceRn (ppr $ items2)
+ traceRn (ppr $ mkGlobalRdrEnv gres)
+
+ return (Just (want_hiding, map fst items2), mkGlobalRdrEnv gres)
+ where
+ -- This environment is how we map names mentioned in the import
+ -- list to the actual Name they correspond to, and the name family
+ -- that the Name belongs to (the AvailInfo). The situation is
+ -- complicated by associated families, which introduce a three-level
+ -- hierachy, where class = grand parent, assoc family = parent, and
+ -- data constructors = children. The occ_env entries for associated
+ -- families needs to capture all this information; hence, we have the
+ -- third component of the environment that gives the class name (=
+ -- grand parent) in case of associated families.
+ --
+ -- This env will have entries for data constructors too,
+ -- they won't make any difference because naked entities like T
+ -- in an import list map to TcOccs, not VarOccs.
+ occ_env :: OccEnv (Name, -- the name
+ AvailInfo, -- the export item providing the name
+ Maybe Name) -- the parent of associated types
+ occ_env = mkOccEnv_C combine [ (nameOccName n, (n, a, Nothing))
+ | a <- all_avails, n <- availNames a]
+ where
+ -- we know that (1) there are at most entries for one name, (2) their
+ -- first component is identical, (3) they are for tys/cls, and (4) one
+ -- entry has the name in its parent position (the other doesn't)
+ combine (name, AvailTC p1 subs1, Nothing)
+ (_ , AvailTC p2 subs2, Nothing)
+ = let
+ (parent, subs) = if p1 == name then (p2, subs1) else (p1, subs2)
+ in
+ (name, AvailTC name subs, Just parent)
+
+ lookup_lie :: Bool -> LIE RdrName -> TcRn [(LIE Name, AvailInfo)]
+ lookup_lie opt_indexedtypes (L loc ieRdr)
+ = do
+ stuff <- setSrcSpan loc $
+ case lookup_ie opt_indexedtypes ieRdr of
+ Failed err -> addErr err >> return []
+ Succeeded a -> return a
+ checkDodgyImport stuff
+ return [ (L loc ie, avail) | (ie,avail) <- stuff ]
+ where
+ -- Warn when importing T(..) if T was exported abstractly
+ checkDodgyImport stuff
+ | IEThingAll n <- ieRdr, (_, AvailTC _ [one]):_ <- stuff
+ = ifOptM Opt_WarnDodgyImports (addWarn (dodgyImportWarn n))
+ -- NB. use the RdrName for reporting the warning
+ checkDodgyImport _
+ = return ()
+
+ -- For each import item, we convert its RdrNames to Names,
+ -- and at the same time construct an AvailInfo corresponding
+ -- to what is actually imported by this item.
+ -- Returns Nothing on error.
+ -- We return a list here, because in the case of an import
+ -- item like C, if we are hiding, then C refers to *both* a
+ -- type/class and a data constructor. Moreover, when we import
+ -- data constructors of an associated family, we need separate
+ -- AvailInfos for the data constructors and the family (as they have
+ -- different parents). See the discussion at occ_env.
+ lookup_ie :: Bool -> IE RdrName -> MaybeErr Message [(IE Name,AvailInfo)]
+ lookup_ie opt_indexedtypes ie
+ = let bad_ie = Failed (badImportItemErr iface decl_spec ie)
+
+ lookup_name rdrName =
+ case lookupOccEnv occ_env (rdrNameOcc rdrName) of
+ Nothing -> bad_ie
+ Just n -> return n
+ in
+ case ie of
+ IEVar n -> do
+ (name, avail, _) <- lookup_name n
+ return [(IEVar name, trimAvail avail name)]
+
+ IEThingAll tc -> do
+ (name, avail@(AvailTC name2 subs), mb_parent) <- lookup_name tc
+ case mb_parent of
+ -- non-associated ty/cls
+ Nothing -> return [(IEThingAll name, avail)]
+ -- associated ty
+ Just parent -> return [(IEThingAll name,
+ AvailTC name2 (subs \\ [name])),
+ (IEThingAll name, AvailTC parent [name])]
+
+ IEThingAbs tc
+ | want_hiding -- hiding ( C )
+ -- Here the 'C' can be a data constructor
+ -- *or* a type/class, or even both
+ -> let tc_name = lookup_name tc
+ dc_name = lookup_name (setRdrNameSpace tc srcDataName)
+ in
+ case catMaybeErr [ tc_name, dc_name ] of
+ [] -> bad_ie
+ names -> return [mkIEThingAbs name | name <- names]
+ | otherwise
+ -> do nameAvail <- lookup_name tc
+ return [mkIEThingAbs nameAvail]
+
+ IEThingWith tc ns -> do
+ (name, AvailTC name2 subnames, mb_parent) <- lookup_name tc
+ let
+ env = mkOccEnv [(nameOccName s, s) | s <- subnames]
+ mb_children = map (lookupOccEnv env . rdrNameOcc) ns
+ children <- if any isNothing mb_children
+ then bad_ie
+ else return (catMaybes mb_children)
+ -- check for proper import of indexed types
+ when (not opt_indexedtypes && any isTyConName children) $
+ Failed (typeItemErr (head . filter isTyConName $ children)
+ (text "in import list"))
+ case mb_parent of
+ -- non-associated ty/cls
+ Nothing -> return [(IEThingWith name children,
+ AvailTC name (name:children))]
+ -- associated ty
+ Just parent -> return [(IEThingWith name children,
+ AvailTC name children),
+ (IEThingWith name children,
+ AvailTC parent [name])]
+
+ _other -> Failed illegalImportItemErr
+ -- could be IEModuleContents, IEGroup, IEDoc, IEDocNamed
+ -- all errors.
+
+ where
+ mkIEThingAbs (n, av, Nothing ) = (IEThingAbs n, trimAvail av n)
+ mkIEThingAbs (n, av, Just parent) = (IEThingAbs n, AvailTC parent [n])
+
+
+catMaybeErr :: [MaybeErr err a] -> [a]
+catMaybeErr ms = [ a | Succeeded a <- ms ]
+\end{code}
+
+\begin{code}
+filterImports2 :: ModIface
+ -> ImpDeclSpec -- The span for the entire import decl
+ -> Maybe (Bool, [LIE RdrName]) -- Import spec; True => hiding
+ -> [AvailInfo] -- What's available
+ -> RnM (Maybe (Bool, [LIE Name]), -- Import spec w/ Names
+ GlobalRdrEnv) -- Same again, but in GRE form
+
+filterImports2 iface decl_spec Nothing all_avails
+ = return (Nothing, mkGlobalRdrEnv (gresFromAvails prov all_avails))
+ where
+ prov = Imported [ImpSpec { is_decl = decl_spec, is_item = ImpAll }]
+
+
+filterImports2 iface decl_spec (Just (want_hiding, import_items)) all_avails
+ = do -- check for errors, convert RdrNames to Names
+ opt_indexedtypes <- doptM Opt_IndexedTypes
+ items1 <- mapM (lookup_lie opt_indexedtypes) import_items
+
+ let items2 :: [(LIE Name, AvailInfo)]
+ items2 = concat items1
+ -- NB the AvailInfo may have duplicates, and several items
+ -- for the same parent; e.g N(x) and N(y)
+
+ names = availsToNameSet (map snd items2)
+ keep n = not (n `elemNameSet` names)
+ pruned_avails = filterAvails keep all_avails
+ hiding_prov = Imported [ImpSpec { is_decl = decl_spec, is_item = ImpAll }]
+
+ gres | want_hiding = gresFromAvails hiding_prov pruned_avails
+ | otherwise = concatMap (gresFromIE decl_spec) items2
+
return (Just (want_hiding, map fst items2), mkGlobalRdrEnv gres)
where
-- This environment is how we map names mentioned in the import
_other -> Failed illegalImportItemErr
-- could be IEModuleContents, IEGroup, IEDoc, IEDocNamed
-- all errors.
-
-catMaybeErr :: [MaybeErr err a] -> [a]
-catMaybeErr ms = [ a | Succeeded a <- ms ]
\end{code}
%************************************************************************
projects / ghc-hetmet.git / blobdiff