\begin{code}
module RnNames (
- rnImports, mkRdrEnvAndImports, importsFromLocalDecls,
- rnExports, mkExportNameSet,
+ rnImports, importsFromLocalDecls,
+ rnExports,
getLocalDeclBinders, extendRdrEnvRn,
reportUnusedNames, reportDeprecations
) where
instDeclATs, isIdxTyDecl,
LIE )
import RnEnv
+import RnHsDoc ( rnHsDoc )
import IfaceEnv ( ifaceExportNames )
import LoadIface ( loadSrcInterface )
import TcRnMonad hiding (LIE)
-import FiniteMap
import PrelNames
import Module
-import Name ( Name, nameSrcLoc, nameOccName, nameModule, isWiredInName,
- nameParent, nameParent_maybe, isExternalName,
- isBuiltInSyntax )
-import NameSet
+import Name
import NameEnv
-import OccName ( srcDataName, isTcOcc, pprNonVarNameSpace,
+import NameSet
+import OccName ( srcDataName, pprNonVarNameSpace,
occNameSpace,
- OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv,
- extendOccEnv )
-import HscTypes ( GenAvailInfo(..), AvailInfo,
+ OccEnv, mkOccEnv, mkOccEnv_C, lookupOccEnv,
+ emptyOccEnv, extendOccEnv )
+import HscTypes ( GenAvailInfo(..), AvailInfo, availNames, availName,
HomePackageTable, PackageIfaceTable,
- mkPrintUnqualified,
+ mkPrintUnqualified, availsToNameSet,
Deprecs(..), ModIface(..), Dependencies(..),
lookupIfaceByModule, ExternalPackageState(..)
)
-import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace,
+import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, Parent(..),
GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts,
- extendGlobalRdrEnv, lookupGlobalRdrEnv, unQualOK, lookupGRE_Name,
+ extendGlobalRdrEnv, lookupGlobalRdrEnv,
+ lookupGRE_RdrName, lookupGRE_Name,
Provenance(..), ImportSpec(..), ImpDeclSpec(..), ImpItemSpec(..),
- importSpecLoc, importSpecModule, isLocalGRE, pprNameProvenance )
+ importSpecLoc, importSpecModule, isLocalGRE, pprNameProvenance,
+ unQualSpecOK, qualSpecOK )
import Outputable
-import UniqFM
-import Maybes ( isNothing, catMaybes, mapCatMaybes, seqMaybe, orElse )
-import SrcLoc ( Located(..), mkGeneralSrcSpan,
+import Maybes
+import SrcLoc ( Located(..), mkGeneralSrcSpan, getLoc,
unLoc, noLoc, srcLocSpan, SrcSpan )
+import FiniteMap
+import ErrUtils
import BasicTypes ( DeprecTxt )
import DriverPhases ( isHsBoot )
-import Util ( notNull )
-import List ( partition )
+import Util
+import ListSetOps
+import Data.List ( partition, concatMap, (\\), delete )
import IO ( openFile, IOMode(..) )
-import Monad ( liftM )
+import Monad ( when )
\end{code}
%************************************************************************
\begin{code}
-rnImports :: [LImportDecl RdrName] -> RnM [LImportDecl Name]
+rnImports :: [LImportDecl RdrName]
+ -> RnM ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
+
rnImports imports
-- PROCESS IMPORT DECLS
-- Do the non {- SOURCE -} ones first, so that we get a helpful
let all_imports = mk_prel_imports this_mod implicit_prelude ++ imports
(source, ordinary) = partition is_source_import all_imports
is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
- get_imports = rnImportDecl this_mod
- stuff1 <- mapM get_imports ordinary
- stuff2 <- mapM get_imports source
- return (stuff1 ++ stuff2)
+ stuff1 <- mapM (rnImportDecl this_mod) ordinary
+ stuff2 <- mapM (rnImportDecl this_mod) source
+ let (decls, rdr_env, imp_avails) = combine (stuff1 ++ stuff2)
+ return (decls, rdr_env, imp_avails)
+
where
-- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();
-- because the former doesn't even look at Prelude.hi for instance
= notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports,
unLoc mod == pRELUDE_NAME ]
+ combine :: [(LImportDecl Name, GlobalRdrEnv, ImportAvails)]
+ -> ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
+ combine = foldr plus ([], emptyGlobalRdrEnv, emptyImportAvails)
+ where plus (decl, gbl_env1, imp_avails1)
+ (decls, gbl_env2, imp_avails2)
+ = (decl:decls,
+ gbl_env1 `plusGlobalRdrEnv` gbl_env2,
+ imp_avails1 `plusImportAvails` imp_avails2)
+
preludeImportDecl :: LImportDecl RdrName
preludeImportDecl
= L loc $
where
loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
-mkRdrEnvAndImports :: [LImportDecl Name] -> RnM (GlobalRdrEnv, ImportAvails)
-mkRdrEnvAndImports imports
- = do this_mod <- getModule
- let get_imports = importsFromImportDecl this_mod
- stuff <- mapM get_imports imports
- let (imp_gbl_envs, imp_avails) = unzip stuff
- gbl_env :: GlobalRdrEnv
- gbl_env = foldr plusGlobalRdrEnv emptyGlobalRdrEnv imp_gbl_envs
-
- all_avails :: ImportAvails
- all_avails = foldr plusImportAvails emptyImportAvails imp_avails
- -- ALL DONE
- return (gbl_env, all_avails)
-
-\end{code}
-\begin{code}
-rnImportDecl :: Module
- -> LImportDecl RdrName
- -> RnM (LImportDecl Name)
-rnImportDecl this_mod (L loc importDecl@(ImportDecl loc_imp_mod_name want_boot qual_only as_mod imp_details))
- = setSrcSpan loc $
- do iface <- loadSrcInterface doc imp_mod_name want_boot
- let qual_mod_name = case as_mod of
- Nothing -> imp_mod_name
- Just another_name -> another_name
- imp_spec = ImpDeclSpec { is_mod = imp_mod_name, is_qual = qual_only,
- is_dloc = loc, is_as = qual_mod_name }
- total_avails <- ifaceExportNames (mi_exports iface)
- importDecl' <- rnImportDecl' iface imp_spec importDecl total_avails
- return (L loc importDecl')
- where imp_mod_name = unLoc loc_imp_mod_name
- doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
-
-rnImportDecl' :: ModIface -> ImpDeclSpec -> ImportDecl RdrName -> NameSet -> RnM (ImportDecl Name)
-rnImportDecl' iface decl_spec (ImportDecl mod_name want_boot qual_only as_mod Nothing) all_names
- = return $ ImportDecl mod_name want_boot qual_only as_mod Nothing
-rnImportDecl' iface decl_spec (ImportDecl mod_name want_boot qual_only as_mod (Just (want_hiding,import_items))) all_names
- = do import_items_mbs <- mapM (srcSpanWrapper) import_items
- let rn_import_items = concat . catMaybes $ import_items_mbs
- return $ ImportDecl mod_name want_boot qual_only as_mod (Just (want_hiding,rn_import_items))
- where
- srcSpanWrapper (L span ieRdr)
- = case get_item ieRdr of
- Nothing
- -> do addErrAt span (badImportItemErr iface decl_spec ieRdr)
- return Nothing
- Just ieNames
- -> return (Just [L span ie | ie <- ieNames])
- occ_env :: OccEnv Name -- Maps OccName to corresponding Name
- occ_env = mkOccEnv [(nameOccName n, n) | n <- nameSetToList all_names]
- -- 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.
- sub_env :: NameEnv [Name]
- sub_env = mkSubNameEnv all_names
-
- get_item :: IE RdrName -> Maybe [IE Name]
- -- Empty result for a bad item.
- -- Singleton result is typical case.
- -- Can have two when we are hiding, and mention C which might be
- -- both a class and a data constructor.
- get_item item@(IEModuleContents _)
- = Nothing
- get_item (IEThingAll tc)
- = do name <- check_name tc
- return [IEThingAll name]
- get_item (IEThingAbs tc)
- | want_hiding -- hiding ( C )
- -- Here the 'C' can be a data constructor
- -- *or* a type/class, or even both
- = case catMaybes [check_name tc, check_name (setRdrNameSpace tc srcDataName)] of
- [] -> Nothing
- names -> return [ IEThingAbs n | n <- names ]
- | otherwise
- = do name <- check_name tc
- return [IEThingAbs name]
- get_item (IEThingWith n ns) -- import (C (A,B))
- = do name <- check_name n
- let env = mkOccEnv [(nameOccName s, s) | s <- subNames sub_env name]
- mb_names = map (lookupOccEnv env . rdrNameOcc) ns
- names <- sequence mb_names
- return [IEThingWith name names]
- get_item (IEVar n)
- = do name <- check_name n
- return [IEVar name]
-
- check_name :: RdrName -> Maybe Name
- check_name rdrName
- = lookupOccEnv occ_env (rdrNameOcc rdrName)
-
-
-importsFromImportDecl :: Module
- -> LImportDecl Name
- -> RnM (GlobalRdrEnv, ImportAvails)
-
-importsFromImportDecl this_mod
- (L loc (ImportDecl loc_imp_mod_name want_boot qual_only as_mod imp_details))
+rnImportDecl :: Module
+ -> LImportDecl RdrName
+ -> RnM (LImportDecl Name, GlobalRdrEnv, ImportAvails)
+
+rnImportDecl this_mod (L loc (ImportDecl loc_imp_mod_name want_boot
+ qual_only as_mod imp_details))
=
- setSrcSpan loc $
+ setSrcSpan loc $ do
-- If there's an error in loadInterface, (e.g. interface
-- file not found) we get lots of spurious errors from 'filterImports'
let
imp_mod_name = unLoc loc_imp_mod_name
doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
- in
- loadSrcInterface doc imp_mod_name want_boot `thenM` \ iface ->
+
+ iface <- loadSrcInterface doc imp_mod_name want_boot
-- Compiler sanity check: if the import didn't say
-- {-# SOURCE #-} we should not get a hi-boot file
- WARN( not want_boot && mi_boot iface, ppr imp_mod_name )
+ WARN( not want_boot && mi_boot iface, ppr imp_mod_name ) (do
-- Issue a user warning for a redundant {- SOURCE -} import
-- NB that we arrange to read all the ordinary imports before
-- any of the {- SOURCE -} imports
warnIf (want_boot && not (mi_boot iface))
- (warnRedundantSourceImport imp_mod_name) `thenM_`
+ (warnRedundantSourceImport imp_mod_name)
let
- imp_mod = mi_module iface
- deprecs = mi_deprecs iface
- is_orph = mi_orphan iface
- deps = mi_deps iface
+ imp_mod = mi_module iface
+ deprecs = mi_deprecs iface
+ is_orph = mi_orphan iface
+ has_finsts = mi_finsts iface
+ deps = mi_deps iface
filtered_exports = filter not_this_mod (mi_exports iface)
not_this_mod (mod,_) = mod /= this_mod
- -- If the module exports anything defined in this module, just ignore it.
- -- Reason: otherwise it looks as if there are two local definition sites
- -- for the thing, and an error gets reported. Easiest thing is just to
- -- filter them out up front. This situation only arises if a module
- -- imports itself, or another module that imported it. (Necessarily,
- -- this invoves a loop.)
+ -- If the module exports anything defined in this module, just
+ -- ignore it. Reason: otherwise it looks as if there are two
+ -- local definition sites for the thing, and an error gets
+ -- reported. Easiest thing is just to filter them out up
+ -- front. This situation only arises if a module imports
+ -- itself, or another module that imported it. (Necessarily,
+ -- this invoves a loop.)
--
-- Tiresome consequence: if you say
-- module A where
Just another_name -> another_name
imp_spec = ImpDeclSpec { is_mod = imp_mod_name, is_qual = qual_only,
is_dloc = loc, is_as = qual_mod_name }
- in
- -- Get the total imports, and filter them according to the import list
- ifaceExportNames filtered_exports `thenM` \ total_avails ->
- filterImports iface imp_spec
- imp_details total_avails `thenM` \ (avail_env, gbl_env) ->
+ -- in
+
+ -- Get the total exports from this module
+ total_avails <- ifaceExportNames filtered_exports
+
+ -- filter the imports according to the import declaration
+ (new_imp_details, gbl_env) <-
+ filterImports2 iface imp_spec imp_details total_avails
- getDOpts `thenM` \ dflags ->
+ dflags <- getDOpts
let
-- Compute new transitive dependencies
imp_mod : dep_orphs deps
| otherwise = dep_orphs deps
+ finsts | has_finsts = ASSERT( not (imp_mod `elem` dep_finsts deps) )
+ imp_mod : dep_finsts deps
+ | otherwise = dep_finsts deps
+
pkg = modulePackageId (mi_module iface)
(dependent_mods, dependent_pkgs)
Just (is_hiding, ls) -> not is_hiding && null ls
other -> False
- -- unqual_avails is the Avails that are visible in *unqualified* form
- -- We need to know this so we know what to export when we see
- -- module M ( module P ) where ...
- -- Then we must export whatever came from P unqualified.
imports = ImportAvails {
- imp_env = unitUFM qual_mod_name avail_env,
imp_mods = unitModuleEnv imp_mod (imp_mod, import_all, loc),
imp_orphs = orphans,
+ imp_finsts = finsts,
imp_dep_mods = mkModDeps dependent_mods,
- imp_dep_pkgs = dependent_pkgs }
+ imp_dep_pkgs = dependent_pkgs
+ }
- in
-- Complain if we import a deprecated module
ifOptM Opt_WarnDeprecations (
case deprecs of
DeprecAll txt -> addWarn (moduleDeprec imp_mod_name txt)
other -> returnM ()
- ) `thenM_`
+ )
+
+ let new_imp_decl = L loc (ImportDecl loc_imp_mod_name want_boot
+ qual_only as_mod new_imp_details)
- returnM (gbl_env, imports)
+ returnM (new_imp_decl, gbl_env, imports)
+ )
warnRedundantSourceImport mod_name
= ptext SLIT("Unnecessary {-# SOURCE #-} in the import of module")
importsFromLocalDecls group
= do { gbl_env <- getGblEnv
- ; names <- getLocalDeclBinders gbl_env group
-
- ; implicit_prelude <- doptM Opt_ImplicitPrelude
- ; let {
- -- Optimisation: filter out names for built-in syntax
- -- They just clutter up the environment (esp tuples), and the parser
- -- will generate Exact RdrNames for them, so the cluttered
- -- envt is no use. To avoid doing this filter all the time,
- -- we use -fno-implicit-prelude as a clue that the filter is
- -- worth while. Really, it's only useful for GHC.Base and GHC.Tuple.
- --
- -- It's worth doing because it makes the environment smaller for
- -- every module that imports the Prelude
- --
- -- Note: don't filter the gbl_env (hence all_names, not filered_all_names
- -- in defn of gres above). Stupid reason: when parsing
- -- data type decls, the constructors start as Exact tycon-names,
- -- and then get turned into data con names by zapping the name space;
- -- but that stops them being Exact, so they get looked up.
- -- Ditto in fixity decls; e.g. infix 5 :
- -- Sigh. It doesn't matter because it only affects the Data.Tuple really.
- -- The important thing is to trim down the exports.
- filtered_names
- | implicit_prelude = names
- | otherwise = filter (not . isBuiltInSyntax) names ;
-
- ; this_mod = tcg_mod gbl_env
- ; imports = emptyImportAvails {
- imp_env = unitUFM (moduleName this_mod) $
- mkNameSet filtered_names
- }
- }
-
- ; rdr_env' <- extendRdrEnvRn (tcg_rdr_env gbl_env) names
-
- ; returnM (gbl_env { tcg_rdr_env = rdr_env',
- tcg_imports = imports `plusImportAvails` tcg_imports gbl_env })
+ ; avails <- getLocalDeclBinders gbl_env group
+
+ ; rdr_env' <- extendRdrEnvRn (tcg_rdr_env gbl_env) avails
+
+ ; traceRn (text "local avails: " <> ppr avails)
+
+ ; returnM (gbl_env { tcg_rdr_env = rdr_env' })
}
-extendRdrEnvRn :: GlobalRdrEnv -> [Name] -> RnM GlobalRdrEnv
+extendRdrEnvRn :: GlobalRdrEnv -> [AvailInfo] -> RnM GlobalRdrEnv
-- Add the new locally-bound names one by one, checking for duplicates as
-- we do so. Remember that in Template Haskell the duplicates
-- might *already be* in the GlobalRdrEnv from higher up the module
-extendRdrEnvRn rdr_env names
- = foldlM add_local rdr_env names
+extendRdrEnvRn rdr_env avails
+ = foldlM add_local rdr_env (gresFromAvails LocalDef avails)
where
- add_local rdr_env name
- | gres <- lookupGlobalRdrEnv rdr_env (nameOccName name)
+ add_local rdr_env gre
+ | gres <- lookupGlobalRdrEnv rdr_env (nameOccName (gre_name gre))
, (dup_gre:_) <- filter isLocalGRE gres -- Check for existing *local* defns
- = do { addDupDeclErr (gre_name dup_gre) name
+ = do { addDupDeclErr (gre_name dup_gre) (gre_name gre)
; return rdr_env }
| otherwise
- = return (extendGlobalRdrEnv rdr_env new_gre)
- where
- new_gre = GRE {gre_name = name, gre_prov = LocalDef}
+ = return (extendGlobalRdrEnv rdr_env gre)
\end{code}
@getLocalDeclBinders@ returns the names for an @HsDecl@. It's
*** See "THE NAMING STORY" in HsDecls ****
-Associated data types: Instances declarations may contain definitions of
-associated data types whose data constructors we need to collect, too.
-However, we need to be careful with the handling of the data type constructor
-of each asscociated type, as it is already defined in the corresponding
-class. We make a new name for it, but don't return it in the 'AvailInfo' (to
-avoid raising a duplicate declaration error; see the helper
-'unavail_main_name').
+Instances of indexed types
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+Indexed data/newtype instances contain data constructors that we need to
+collect, too. Moreover, we need to descend into the data/newtypes instances
+of associated families.
+
+We need to be careful with the handling of the type constructor of each type
+instance as the family constructor is already defined, and we want to avoid
+raising a duplicate declaration error. So, we make a new name for it, but
+don't return it in the 'AvailInfo'.
\begin{code}
-getLocalDeclBinders :: TcGblEnv -> HsGroup RdrName -> RnM [Name]
-getLocalDeclBinders gbl_env (HsGroup {hs_valds = ValBindsIn val_decls val_sigs,
+getLocalDeclBinders :: TcGblEnv -> HsGroup RdrName -> RnM [AvailInfo]
+getLocalDeclBinders gbl_env (HsGroup {hs_valds = ValBindsIn val_decls val_sigs,
hs_tyclds = tycl_decls,
hs_instds = inst_decls,
hs_fords = foreign_decls })
= do { tc_names_s <- mappM new_tc tycl_decls
; at_names_s <- mappM inst_ats inst_decls
; val_names <- mappM new_simple val_bndrs
- ; return (foldr (++) val_names (tc_names_s ++ concat at_names_s)) }
+ ; return (val_names ++ tc_names_s ++ concat at_names_s) }
where
mod = tcg_mod gbl_env
is_hs_boot = isHsBoot (tcg_src gbl_env) ;
-- In a hs-boot file, the value binders come from the
-- *signatures*, and there should be no foreign binders
- new_simple rdr_name = newTopSrcBinder mod Nothing rdr_name
+ new_simple rdr_name = do
+ nm <- newTopSrcBinder mod rdr_name
+ return (Avail nm)
sig_hs_bndrs = [nm | L _ (TypeSig nm _) <- val_sigs]
val_hs_bndrs = collectHsBindLocatedBinders val_decls
for_hs_bndrs = [nm | L _ (ForeignImport nm _ _) <- foreign_decls]
new_tc tc_decl
- = do { main_name <- newTopSrcBinder mod Nothing main_rdr
- ; sub_names <- mappM (newTopSrcBinder mod (Just main_name)) sub_rdrs
- ; if isIdxTyDecl (unLoc tc_decl) -- index type definitions
- then return ( sub_names) -- are usage occurences
- else return (main_name : sub_names) }
- where
- (main_rdr : sub_rdrs) = tyClDeclNames (unLoc tc_decl)
+ | isIdxTyDecl (unLoc tc_decl)
+ = do { main_name <- lookupFamInstDeclBndr mod main_rdr
+ ; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
+ ; return (AvailTC main_name sub_names) }
+ -- main_name is not bound here!
+ | otherwise
+ = do { main_name <- newTopSrcBinder mod main_rdr
+ ; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
+ ; return (AvailTC main_name (main_name : sub_names)) }
+ where
+ (main_rdr : sub_rdrs) = tyClDeclNames (unLoc tc_decl)
inst_ats inst_decl
= mappM new_tc (instDeclATs (unLoc inst_decl))
+
+getLocalDeclBinders _ _ = panic "getLocalDeclBinders" -- ValBindsOut can't happen
\end{code}
\begin{code}
filterImports :: ModIface
-> ImpDeclSpec -- The span for the entire import decl
- -> Maybe (Bool, [LIE Name]) -- Import spec; True => hiding
- -> NameSet -- What's available
- -> RnM (NameSet, -- What's imported (qualified or unqualified)
+ -> 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
-
- -- Complains if import spec mentions things that the module doesn't export
- -- Warns/informs if import spec contains duplicates.
-mkGenericRdrEnv decl_spec names
- = mkGlobalRdrEnv [ GRE { gre_name = name, gre_prov = Imported [imp_spec] }
- | name <- nameSetToList names ]
+filterImports iface decl_spec Nothing all_avails
+ = return (Nothing, mkGlobalRdrEnv (gresFromAvails prov all_avails))
where
- imp_spec = ImpSpec { is_decl = decl_spec, is_item = ImpAll }
-
-filterImports iface decl_spec Nothing all_names
- = return (all_names, mkGenericRdrEnv decl_spec all_names)
-
-filterImports iface decl_spec (Just (want_hiding, import_items)) all_names
- = mapM (addLocM get_item) import_items >>= \gres_s ->
- let gres = concat gres_s
- specified_names = mkNameSet (map gre_name gres)
- in if not want_hiding then
- return (specified_names, mkGlobalRdrEnv gres)
- else let keep n = not (n `elemNameSet` specified_names)
- pruned_avails = filterNameSet keep all_names
- in return (pruned_avails, mkGenericRdrEnv decl_spec pruned_avails)
+ prov = Imported [ImpSpec { is_decl = decl_spec, is_item = ImpAll }]
+
+
+filterImports 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
- sub_env :: NameEnv [Name] -- Classify each name by its parent
- sub_env = mkSubNameEnv all_names
+ -- 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.
- succeed_with :: Bool -> [Name] -> RnM [GlobalRdrElt]
- succeed_with all_explicit names
- = do { loc <- getSrcSpanM
- ; returnM (map (mk_gre loc) names) }
where
- mk_gre loc name = GRE { gre_name = name,
- gre_prov = Imported [imp_spec] }
- where
- imp_spec = ImpSpec { is_decl = decl_spec, is_item = item_spec }
- item_spec = ImpSome { is_explicit = explicit, is_iloc = loc }
- explicit = all_explicit || isNothing (nameParent_maybe name)
-
- get_item :: IE Name -> RnM [GlobalRdrElt]
- -- Empty result for a bad item.
- -- Singleton result is typical case.
- -- Can have two when we are hiding, and mention C which might be
- -- both a class and a data constructor.
- get_item item@(IEModuleContents _)
- -- This case should be filtered out by 'rnImports'.
- = panic "filterImports: IEModuleContents?"
-
- get_item (IEThingAll name)
- = case subNames sub_env name of
- [] -> -- This occurs when you import T(..), but
- -- only export T abstractly.
- do ifOptM Opt_WarnDodgyImports (addWarn (dodgyImportWarn name))
- succeed_with False [name]
- names -> succeed_with False (name:names)
-
- get_item (IEThingAbs name)
- = succeed_with True [name]
-
- get_item (IEThingWith name names)
- = succeed_with True (name:names)
- get_item (IEVar name)
- = succeed_with True [name]
+ 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
+ -- list to the actual Name they correspond to, and the family
+ -- that the Name belongs to (an AvailInfo).
+ --
+ -- 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,AvailInfo)
+ occ_env = mkOccEnv [ (nameOccName n, (n,a))
+ | a <- all_avails, n <- availNames a ]
+
+ 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.
+ 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) <- lookup_name tc
+ return [(IEThingAll name, avail)]
+
+ 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 [ (IEThingAbs n, trimAvail av n)
+ | (n,av) <- names ]
+ | otherwise
+ -> do (name,avail) <- lookup_name tc
+ return [(IEThingAbs name, AvailTC name [name])]
+
+ IEThingWith n ns -> do
+ (name,avail) <- lookup_name n
+ case avail of
+ AvailTC nm subnames | nm == name -> do
+ let env = mkOccEnv [ (nameOccName s, s)
+ | s <- subnames ]
+ let 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"))
+ return [(IEThingWith name children, AvailTC name (name:children))]
+
+ _otherwise -> bad_ie
+
+ _other -> Failed illegalImportItemErr
+ -- could be IEModuleContents, IEGroup, IEDoc, IEDocNamed
+ -- all errors.
+\end{code}
+
+%************************************************************************
+%* *
+ Import/Export Utils
+%* *
+%************************************************************************
+
+\begin{code}
+-- | make a 'GlobalRdrEnv' where all the elements point to the same
+-- import declaration (useful for "hiding" imports, or imports with
+-- no details).
+gresFromAvails :: Provenance -> [AvailInfo] -> [GlobalRdrElt]
+gresFromAvails prov avails
+ = concatMap (gresFromAvail (const prov)) avails
+
+gresFromAvail :: (Name -> Provenance) -> AvailInfo -> [GlobalRdrElt]
+gresFromAvail prov_fn avail
+ = [ GRE {gre_name = n,
+ gre_par = availParent n avail,
+ gre_prov = prov_fn n}
+ | n <- availNames avail ]
+
+greAvail :: GlobalRdrElt -> AvailInfo
+greAvail gre = mkUnitAvail (gre_name gre) (gre_par gre)
+
+mkUnitAvail :: Name -> Parent -> AvailInfo
+mkUnitAvail me (ParentIs p) = AvailTC p [me]
+mkUnitAvail me NoParent | isTyConName me = AvailTC me [me]
+ | otherwise = Avail me
+
+plusAvail (Avail n1) (Avail n2) = Avail n1
+plusAvail (AvailTC n1 ns1) (AvailTC n2 ns2) = AvailTC n2 (ns1 `unionLists` ns2)
+plusAvail a1 a2 = pprPanic "RnEnv.plusAvail" (hsep [ppr a1,ppr a2])
+
+availParent :: Name -> AvailInfo -> Parent
+availParent n (Avail _) = NoParent
+availParent n (AvailTC m ms) | n==m = NoParent
+ | otherwise = ParentIs m
+
+trimAvail :: AvailInfo -> Name -> AvailInfo
+trimAvail (Avail n) m = Avail n
+trimAvail (AvailTC n ns) m = ASSERT( m `elem` ns) AvailTC n [m]
+
+-- | filters 'AvailInfo's by the given predicate
+filterAvails :: (Name -> Bool) -> [AvailInfo] -> [AvailInfo]
+filterAvails keep avails = foldr (filterAvail keep) [] avails
+
+-- | filters an 'AvailInfo' by the given predicate
+filterAvail :: (Name -> Bool) -> AvailInfo -> [AvailInfo] -> [AvailInfo]
+filterAvail keep ie rest =
+ case ie of
+ Avail n | keep n -> ie : rest
+ | otherwise -> rest
+ AvailTC tc ns ->
+ let left = filter keep ns in
+ if null left then rest else AvailTC tc left : rest
+
+-- | Given an import/export spec, construct the appropriate 'GlobalRdrElt's.
+gresFromIE :: ImpDeclSpec -> (LIE Name, AvailInfo) -> [GlobalRdrElt]
+gresFromIE decl_spec (L loc ie, avail)
+ = gresFromAvail prov_fn avail
+ where
+ is_explicit = case ie of
+ IEThingAll name -> \n -> n==name
+ other -> \n -> True
+ prov_fn name = Imported [imp_spec]
+ where
+ imp_spec = ImpSpec { is_decl = decl_spec, is_item = item_spec }
+ item_spec = ImpSome { is_explicit = is_explicit name, is_iloc = loc }
+
+mkChildEnv :: [GlobalRdrElt] -> NameEnv [Name]
+mkChildEnv gres = foldr add emptyNameEnv gres
+ where
+ add (GRE { gre_name = n, gre_par = ParentIs p }) env = extendNameEnv_C (++) env p [n]
+ add other_gre env = env
+
+findChildren :: NameEnv [Name] -> Name -> [Name]
+findChildren env n = lookupNameEnv env n `orElse` []
+\end{code}
+
+---------------------------------------
+ AvailEnv and friends
+
+All this AvailEnv stuff is hardly used; only in a very small
+part of RnNames. Todo: remove?
+---------------------------------------
+
+\begin{code}
+type AvailEnv = NameEnv AvailInfo -- Maps a Name to the AvailInfo that contains it
+
+emptyAvailEnv :: AvailEnv
+emptyAvailEnv = emptyNameEnv
+
+unitAvailEnv :: AvailInfo -> AvailEnv
+unitAvailEnv a = unitNameEnv (availName a) a
+
+plusAvailEnv :: AvailEnv -> AvailEnv -> AvailEnv
+plusAvailEnv = plusNameEnv_C plusAvail
+
+availEnvElts :: AvailEnv -> [AvailInfo]
+availEnvElts = nameEnvElts
+
+addAvail :: AvailEnv -> AvailInfo -> AvailEnv
+addAvail avails avail = extendNameEnv_C plusAvail avails (availName avail) avail
+
+mkAvailEnv :: [AvailInfo] -> AvailEnv
+ -- 'avails' may have several items with the same availName
+ -- E.g import Ix( Ix(..), index )
+ -- will give Ix(Ix,index,range) and Ix(index)
+ -- We want to combine these; addAvail does that
+mkAvailEnv avails = foldl addAvail emptyAvailEnv avails
+
+-- After combining the avails, we need to ensure that the parent name is the
+-- first entry in the list of subnames, if it is included at all. (Subsequent
+-- functions rely on that.)
+normaliseAvail :: AvailInfo -> AvailInfo
+normaliseAvail avail@(Avail _) = avail
+normaliseAvail (AvailTC name subs) = AvailTC name subs'
+ where
+ subs' = if name `elem` subs then name : (delete name subs) else subs
+
+-- | combines 'AvailInfo's from the same family
+nubAvails :: [AvailInfo] -> [AvailInfo]
+nubAvails avails = map normaliseAvail . nameEnvElts . mkAvailEnv $ avails
\end{code}
\begin{code}
type ExportAccum -- The type of the accumulating parameter of
-- the main worker function in rnExports
- = ([ModuleName], -- 'module M's seen so far
+ = ([LIE Name], -- Export items with Names
ExportOccMap, -- Tracks exported occurrence names
- NameSet) -- The accumulated exported stuff
-emptyExportAccum = ([], emptyOccEnv, emptyNameSet)
+ [AvailInfo]) -- The accumulated exported stuff
+ -- Not nub'd!
+
+emptyExportAccum = ([], emptyOccEnv, [])
type ExportOccMap = OccEnv (Name, IE RdrName)
-- Tracks what a particular exported OccName
-- it came from. It's illegal to export two distinct things
-- that have the same occurrence name
-rnExports :: Maybe [LIE RdrName]
- -> RnM (Maybe [LIE Name])
-rnExports Nothing = return Nothing
-rnExports (Just exports)
- = do TcGblEnv { tcg_imports = ImportAvails { imp_env = imp_env } } <- getGblEnv
- let sub_env :: NameEnv [Name] -- Classify each name by its parent
- sub_env = mkSubNameEnv (foldUFM unionNameSets emptyNameSet imp_env)
- rnExport (IEVar rdrName)
- = do name <- lookupGlobalOccRn rdrName
- return (IEVar name)
- rnExport (IEThingAbs rdrName)
- = do name <- lookupGlobalOccRn rdrName
- return (IEThingAbs name)
- rnExport (IEThingAll rdrName)
- = do name <- lookupGlobalOccRn rdrName
- return (IEThingAll name)
- rnExport ie@(IEThingWith rdrName rdrNames)
- = do name <- lookupGlobalOccRn rdrName
- if isUnboundName name
- then return (IEThingWith name [])
- else do
- let env = mkOccEnv [(nameOccName s, s) | s <- subNames sub_env name]
- mb_names = map (lookupOccEnv env . rdrNameOcc) rdrNames
- if any isNothing mb_names
- then do addErr (exportItemErr ie)
- return (IEThingWith name [])
- else return (IEThingWith name (catMaybes mb_names))
- rnExport (IEModuleContents mod)
- = return (IEModuleContents mod)
- rn_exports <- mapM (wrapLocM rnExport) exports
- return (Just rn_exports)
-
-mkExportNameSet :: Bool -- False => no 'module M(..) where' header at all
- -> Maybe ([LIE Name], [LIE RdrName]) -- Nothing => no explicit export list
- -> RnM NameSet
+rnExports :: Bool -- False => no 'module M(..) where' header at all
+ -> Maybe [LIE RdrName] -- Nothing => no explicit export list
+ -> RnM (Maybe [LIE Name], [AvailInfo])
+
-- Complains if two distinct exports have same OccName
-- Warns about identical exports.
-- Complains about exports items not in scope
-mkExportNameSet explicit_mod exports
- = do TcGblEnv { tcg_rdr_env = rdr_env,
+rnExports explicit_mod exports
+ = do TcGblEnv { tcg_mod = this_mod,
+ tcg_rdr_env = rdr_env,
tcg_imports = imports } <- getGblEnv
-- If the module header is omitted altogether, then behave
-- Reason: don't want to complain about 'main' not in scope
-- in interactive mode
ghc_mode <- getGhcMode
- real_exports <- case () of
- () | explicit_mod
- -> return exports
- | ghc_mode == Interactive
- -> return Nothing
- | otherwise
- -> do mainName <- lookupGlobalOccRn main_RDR_Unqual
- return (Just ([noLoc (IEVar mainName)]
- ,[noLoc (IEVar main_RDR_Unqual)]))
- -- ToDo: the 'noLoc' here is unhelpful if 'main' turns out to be out of scope
- exports_from_avail real_exports rdr_env imports
-
-
-exports_from_avail Nothing rdr_env imports
- = -- Export all locally-defined things
- -- We do this by filtering the global RdrEnv,
- -- keeping only things that are locally-defined
- return (mkNameSet [ gre_name gre
- | gre <- globalRdrEnvElts rdr_env,
- isLocalGRE gre ])
-
-exports_from_avail (Just (items,origItems)) rdr_env (ImportAvails { imp_env = imp_env })
- = do (_, _, exports) <- foldlM do_litem emptyExportAccum (zip items origItems)
- return exports
+ real_exports <-
+ case () of
+ () | explicit_mod
+ -> return exports
+ | ghc_mode == Interactive
+ -> return Nothing
+ | otherwise
+ -> do mainName <- lookupGlobalOccRn main_RDR_Unqual
+ return (Just ([noLoc (IEVar main_RDR_Unqual)]))
+ -- ToDo: the 'noLoc' here is unhelpful if 'main' turns
+ -- out to be out of scope
+
+ (exp_spec, avails) <- exports_from_avail real_exports rdr_env imports this_mod
+
+ return (exp_spec, nubAvails avails) -- Combine families
+
+exports_from_avail :: Maybe [LIE RdrName]
+ -- Nothing => no explicit export list
+ -> GlobalRdrEnv
+ -> ImportAvails
+ -> Module
+ -> RnM (Maybe [LIE Name], [AvailInfo])
+
+exports_from_avail Nothing rdr_env imports this_mod
+ = -- The same as (module M) where M is the current module name,
+ -- so that's how we handle it.
+ let
+ avails = [ greAvail gre | gre <- globalRdrEnvElts rdr_env,
+ isLocalGRE gre ]
+ in
+ return (Nothing, avails)
+
+exports_from_avail (Just rdr_items) rdr_env imports this_mod
+ = do (ie_names, _, exports) <- foldlM do_litem emptyExportAccum rdr_items
+
+ return (Just ie_names, exports)
where
- sub_env :: NameEnv [Name] -- Classify each name by its parent
- sub_env = mkSubNameEnv (foldUFM unionNameSets emptyNameSet imp_env)
+ do_litem :: ExportAccum -> LIE RdrName -> RnM ExportAccum
+ do_litem acc lie = setSrcSpan (getLoc lie) (exports_from_item acc lie)
- do_litem :: ExportAccum -> (LIE Name, LIE RdrName) -> RnM ExportAccum
- do_litem acc (ieName, ieRdr)
- = addLocM (exports_from_item acc (unLoc ieRdr)) ieName
+ kids_env :: NameEnv [Name] -- Maps a parent to its in-scope children
+ kids_env = mkChildEnv (globalRdrEnvElts rdr_env)
- exports_from_item :: ExportAccum -> IE RdrName -> IE Name -> RnM ExportAccum
- exports_from_item acc@(mods, occs, exports) ieRdr@(IEModuleContents mod) ie
- | mod `elem` mods -- Duplicate export of M
+ exports_from_item :: ExportAccum -> LIE RdrName -> RnM ExportAccum
+ exports_from_item acc@(ie_names, occs, exports)
+ (L loc ie@(IEModuleContents mod))
+ | let earlier_mods = [ mod | (L _ (IEModuleContents mod)) <- ie_names ]
+ , mod `elem` earlier_mods -- Duplicate export of M
= do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
warnIf warn_dup_exports (dupModuleExport mod) ;
returnM acc }
| otherwise
- = case lookupUFM imp_env mod of
- Nothing -> do addErr (modExportErr mod)
- return acc
- Just names
- -> do let new_exports = filterNameSet (inScopeUnqual rdr_env) names
- -- This check_occs not only finds conflicts between this item
- -- and others, but also internally within this item. That is,
- -- if 'M.x' is in scope in several ways, we'll have several
- -- members of mod_avails with the same OccName.
- occs' <- check_occs ieRdr occs (nameSetToList new_exports)
- return (mod:mods, occs', exports `unionNameSets` new_exports)
-
- exports_from_item acc@(mods, occs, exports) ieRdr ie
- = if isUnboundName (ieName ie)
- then return acc -- Avoid error cascade
- else let new_exports = filterAvail ie sub_env in
- do -- checkErr (not (null (drop 1 new_exports))) (exportItemErr ie)
- checkForDodgyExport ie new_exports
- occs' <- check_occs ieRdr occs new_exports
- return (mods, occs', addListToNameSet exports new_exports)
-
--------------------------------
-filterAvail :: IE Name -- Wanted
- -> NameEnv [Name] -- Maps type/class names to their sub-names
- -> [Name]
-
-filterAvail (IEVar n) subs = [n]
-filterAvail (IEThingAbs n) subs = [n]
-filterAvail (IEThingAll n) subs = n : subNames subs n
-filterAvail (IEThingWith n ns) subs = n : ns
-filterAvail (IEModuleContents _) _ = panic "filterAvail"
-
-subNames :: NameEnv [Name] -> Name -> [Name]
-subNames env n = lookupNameEnv env n `orElse` []
-
-mkSubNameEnv :: NameSet -> NameEnv [Name]
--- Maps types and classes to their constructors/classops respectively
--- This mapping just makes it easier to deal with A(..) export items
-mkSubNameEnv names
- = foldNameSet add_name emptyNameEnv names
- where
- add_name name env
- | Just parent <- nameParent_maybe name
- = extendNameEnv_C (\ns _ -> name:ns) env parent [name]
- | otherwise = env
+ = do { implicit_prelude <- doptM Opt_ImplicitPrelude
+ ; let gres = filter (isModuleExported implicit_prelude mod)
+ (globalRdrEnvElts rdr_env)
+
+ ; warnIf (null gres) (nullModuleExport mod)
+
+ ; occs' <- check_occs ie occs (map gre_name gres)
+ -- This check_occs not only finds conflicts
+ -- between this item and others, but also
+ -- internally within this item. That is, if
+ -- 'M.x' is in scope in several ways, we'll have
+ -- several members of mod_avails with the same
+ -- OccName.
+ ; return (L loc (IEModuleContents mod) : ie_names,
+ occs', map greAvail gres ++ exports) }
+
+ exports_from_item acc@(lie_names, occs, exports) (L loc ie)
+ | isDoc ie
+ = do new_ie <- lookup_doc_ie ie
+ return (L loc new_ie : lie_names, occs, exports)
--------------------------------
-inScopeUnqual :: GlobalRdrEnv -> Name -> Bool
--- Checks whether the Name is in scope unqualified,
--- regardless of whether it's ambiguous or not
-inScopeUnqual env n = any unQualOK (lookupGRE_Name env n)
+ | otherwise
+ = do (new_ie, avail) <- lookup_ie ie
+ if isUnboundName (ieName new_ie)
+ then return acc -- Avoid error cascade
+ else do
+
+ occs' <- check_occs ie occs (availNames avail)
+
+ return (L loc new_ie : lie_names, occs', avail : exports)
+
+ -------------
+ lookup_ie :: IE RdrName -> RnM (IE Name, AvailInfo)
+ lookup_ie (IEVar rdr)
+ = do gre <- lookupGreRn rdr
+ return (IEVar (gre_name gre), greAvail gre)
+
+ lookup_ie (IEThingAbs rdr)
+ = do name <- lookupGlobalOccRn rdr
+ case lookupGRE_RdrName rdr rdr_env of
+ [] -> panic "RnNames.lookup_ie"
+ elt:_ -> case gre_par elt of
+ NoParent -> return (IEThingAbs name,
+ AvailTC name [name])
+ ParentIs p -> return (IEThingAbs name,
+ AvailTC p [name])
+
+ lookup_ie ie@(IEThingAll rdr)
+ = do name <- lookupGlobalOccRn rdr
+ let kids = findChildren kids_env name
+ when (null kids)
+ (if (isTyConName name) then addWarn (dodgyExportWarn name)
+ -- This occurs when you export T(..), but
+ -- only import T abstractly, or T is a synonym.
+ else addErr (exportItemErr ie))
+
+ return (IEThingAll name, AvailTC name (name:kids))
+
+ lookup_ie ie@(IEThingWith rdr sub_rdrs)
+ = do name <- lookupGlobalOccRn rdr
+ if isUnboundName name
+ then return (IEThingWith name [], AvailTC name [name])
+ else do
+ let env = mkOccEnv [ (nameOccName s, s)
+ | s <- findChildren kids_env name ]
+ mb_names = map (lookupOccEnv env . rdrNameOcc) sub_rdrs
+ if any isNothing mb_names
+ then do addErr (exportItemErr ie)
+ return (IEThingWith name [], AvailTC name [name])
+ else do let names = catMaybes mb_names
+ optIdxTypes <- doptM Opt_IndexedTypes
+ when (not optIdxTypes && any isTyConName names) $
+ addErr (typeItemErr ( head
+ . filter isTyConName
+ $ names )
+ (text "in export list"))
+ return (IEThingWith name names, AvailTC name (name:names))
+
+ lookup_ie ie = panic "lookup_ie" -- Other cases covered earlier
+
+ -------------
+ lookup_doc_ie :: IE RdrName -> RnM (IE Name)
+ lookup_doc_ie (IEGroup lev doc) = do rn_doc <- rnHsDoc doc
+ return (IEGroup lev rn_doc)
+ lookup_doc_ie (IEDoc doc) = do rn_doc <- rnHsDoc doc
+ return (IEDoc rn_doc)
+ lookup_doc_ie (IEDocNamed str) = return (IEDocNamed str)
+ lookup_doc_ie ie = panic "lookup_doc_ie" -- Other cases covered earlier
+
+
+isDoc (IEDoc _) = True
+isDoc (IEDocNamed _) = True
+isDoc (IEGroup _ _) = True
+isDoc _ = False
-------------------------------
-checkForDodgyExport :: IE Name -> [Name] -> RnM ()
-checkForDodgyExport ie@(IEThingAll tc) [n]
- | isTcOcc (nameOccName n) = addWarn (dodgyExportWarn tc)
- -- This occurs when you export T(..), but
- -- only import T abstractly, or T is a synonym.
- -- The single [n] is the type or class itself
- | otherwise = addErr (exportItemErr ie)
- -- This happes if you export x(..), which is bogus
-checkForDodgyExport _ _ = return ()
+isModuleExported :: Bool -> ModuleName -> GlobalRdrElt -> Bool
+-- True if the thing is in scope *both* unqualified, *and* with qualifier M
+isModuleExported implicit_prelude mod (GRE { gre_name = name, gre_prov = prov })
+ | implicit_prelude && isBuiltInSyntax name = False
+ -- Optimisation: filter out names for built-in syntax
+ -- They just clutter up the environment (esp tuples), and the parser
+ -- will generate Exact RdrNames for them, so the cluttered
+ -- envt is no use. To avoid doing this filter all the time,
+ -- we use -fno-implicit-prelude as a clue that the filter is
+ -- worth while. Really, it's only useful for GHC.Base and GHC.Tuple.
+ --
+ -- It's worth doing because it makes the environment smaller for
+ -- every module that imports the Prelude
+ | otherwise
+ = case prov of
+ LocalDef -> moduleName (nameModule name) == mod
+ Imported is -> any unQualSpecOK is && any (qualSpecOK mod) is
-------------------------------
check_occs :: IE RdrName -> ExportOccMap -> [Name] -> RnM ExportOccMap
-- Report on all deprecated uses; hence allUses
all_gres = globalRdrEnvElts (tcg_rdr_env tcg_env)
- check hpt pit (GRE {gre_name = name, gre_prov = Imported (imp_spec:_)})
+ check hpt pit gre@(GRE {gre_name = name, gre_prov = Imported (imp_spec:_)})
| name `elemNameSet` used_names
- , Just deprec_txt <- lookupDeprec dflags hpt pit name
+ , Just deprec_txt <- lookupDeprec dflags hpt pit gre
= addWarnAt (importSpecLoc imp_spec)
(sep [ptext SLIT("Deprecated use of") <+>
pprNonVarNameSpace (occNameSpace (nameOccName name)) <+>
-- interface
lookupDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
- -> Name -> Maybe DeprecTxt
-lookupDeprec dflags hpt pit n
- = case lookupIfaceByModule dflags hpt pit (nameModule n) of
- Just iface -> mi_dep_fn iface n `seqMaybe` -- Bleat if the thing, *or
- mi_dep_fn iface (nameParent n) -- its parent*, is deprec'd
+ -> GlobalRdrElt -> Maybe DeprecTxt
+lookupDeprec dflags hpt pit gre
+ = case lookupIfaceByModule dflags hpt pit (nameModule name) of
+ Just iface -> mi_dep_fn iface name `seqMaybe` -- Bleat if the thing, *or
+ case gre_par gre of
+ ParentIs p -> mi_dep_fn iface p -- its parent*, is deprec'd
+ NoParent -> Nothing
Nothing
- | isWiredInName n -> Nothing
+ | isWiredInName name -> Nothing
-- We have not necessarily loaded the .hi file for a
-- wired-in name (yet), although we *could*.
-- And we never deprecate them
- | otherwise -> pprPanic "lookupDeprec" (ppr n)
+ | otherwise -> pprPanic "lookupDeprec" (ppr name)
-- By now all the interfaces should have been loaded
-
-gre_is_used :: NameSet -> GlobalRdrElt -> Bool
-gre_is_used used_names gre = gre_name gre `elemNameSet` used_names
+ where
+ name = gre_name gre
\end{code}
%*********************************************************
; warnDuplicateImports defined_and_used
; printMinimalImports minimal_imports }
where
- used_names, all_used_names :: NameSet
+ used_names :: NameSet
used_names = findUses (tcg_dus gbl_env) emptyNameSet
-- NB: currently, if f x = g, we only treat 'g' as used if 'f' is used
-- Hence findUses
- all_used_names = used_names `unionNameSets`
- mkNameSet (mapCatMaybes nameParent_maybe (nameSetToList used_names))
- -- A use of C implies a use of T,
- -- if C was brought into scope by T(..) or T(C)
-
-- Collect the defined names from the in-scope environment
defined_names :: [GlobalRdrElt]
defined_names = globalRdrEnvElts (tcg_rdr_env gbl_env)
-- Note that defined_and_used, defined_but_not_used
-- are both [GRE]; that's why we need defined_and_used
- -- rather than just all_used_names
+ -- rather than just used_names
defined_and_used, defined_but_not_used :: [GlobalRdrElt]
(defined_and_used, defined_but_not_used)
- = partition (gre_is_used all_used_names) defined_names
+ = partition (gre_is_used used_names) defined_names
+ kids_env = mkChildEnv defined_names
+ -- This is done in mkExports too; duplicated work
+
+ gre_is_used :: NameSet -> GlobalRdrElt -> Bool
+ gre_is_used used_names (GRE {gre_name = name})
+ = name `elemNameSet` used_names
+ || any (`elemNameSet` used_names) (findChildren kids_env name)
+ -- A use of C implies a use of T,
+ -- if C was brought into scope by T(..) or T(C)
+
-- Filter out the ones that are
-- (a) defined in this module, and
-- (b) not defined by a 'deriving' clause
-- We've carefully preserved the provenance so that we can
-- construct minimal imports that import the name by (one of)
-- the same route(s) as the programmer originally did.
- add_name (GRE {gre_name = n, gre_prov = Imported imp_specs}) acc
- = addToFM_C plusAvailEnv acc (importSpecModule (head imp_specs))
- (unitAvailEnv (mk_avail n (nameParent_maybe n)))
- add_name other acc
- = acc
+ add_name gre@(GRE {gre_prov = Imported (imp_spec:_)}) acc
+ = addToFM_C plusAvailEnv acc
+ (importSpecModule imp_spec) (unitAvailEnv (greAvail gre))
+ add_name gre acc = acc -- Local
-- Modules mentioned as 'module M' in the export list
expall_mods = case export_decls of
-- qualified imports into account. But it's an improvement.
add_expall mod acc = addToFM_C plusAvailEnv acc mod emptyAvailEnv
- -- n is the name of the thing, p is the name of its parent
- mk_avail n (Just p) = AvailTC p [p,n]
- mk_avail n Nothing | isTcOcc (nameOccName n) = AvailTC n [n]
- | otherwise = Avail n
-
add_inst_mod (mod,_,_) acc
| mod_name `elemFM` acc = acc -- We import something already
| otherwise = addToFM acc mod_name emptyAvailEnv
source_import | mi_boot iface = ptext SLIT("(hi-boot interface)")
| otherwise = empty
+illegalImportItemErr = ptext SLIT("Illegal import item")
+
dodgyImportWarn item = dodgyMsg (ptext SLIT("import")) item
dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) item
ptext SLIT("suggests that") <+> quotes (ppr tc) <+> ptext SLIT("has constructor or class methods"),
ptext SLIT("but it has none; it is a type synonym or abstract type or class") ]
-modExportErr mod
- = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (ppr mod)]
-
exportItemErr export_item
= sep [ ptext SLIT("The export item") <+> quotes (ppr export_item),
ptext SLIT("attempts to export constructors or class methods that are not visible here") ]
+typeItemErr name wherestr
+ = sep [ ptext SLIT("Using 'type' tag on") <+> quotes (ppr name) <+> wherestr,
+ ptext SLIT("Use -findexed-types to enable this extension") ]
+
exportClashErr global_env name1 name2 ie1 ie2
= vcat [ ptext SLIT("Conflicting exports for") <+> quotes (ppr occ) <> colon
, ppr_export ie1 name1
quotes (ptext SLIT("Module") <+> ppr mod),
ptext SLIT("in export list")]
+nullModuleExport mod
+ = ptext SLIT("The export item `module") <+> ppr mod <> ptext SLIT("' exports nothing")
+
moduleDeprec mod txt
= sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"),
nest 4 (ppr txt) ]