%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnNames]{Extracting imported and top-level names in scope}
\begin{code}
module RnNames (
- getGlobalNames
+ ExportAvails, getGlobalNames, exportsFromAvail
) where
#include "HsVersions.h"
-import CmdLineOpts ( opt_NoImplicitPrelude, opt_WarnDuplicateExports,
- opt_SourceUnchanged
- )
-
-import HsSyn ( HsModule(..), ImportDecl(..), HsDecl(..),
- IE(..), ieName,
- FixityDecl(..),
- collectTopBinders
- )
-import RdrHsSyn ( RdrNameHsDecl(..), RdrName(..), RdrNameIE(..), RdrNameImportDecl,
- RdrNameHsModule, RdrNameFixityDecl,
- rdrNameOcc, ieOcc
- )
-import RnHsSyn ( RenamedHsModule(..), RenamedFixityDecl(..) )
-import RnIfaces ( getInterfaceExports, getDeclBinders, recordSlurp, checkUpToDate )
-import BasicTypes ( IfaceFlavour(..) )
+import CmdLineOpts ( DynFlag(..) )
+
+import HsSyn ( HsModule(..), HsDecl(..), IE(..), ieName, ImportDecl(..),
+ ForeignDecl(..),
+ collectLocatedHsBinders
+ )
+import RdrHsSyn ( RdrNameIE, RdrNameImportDecl,
+ RdrNameHsModule, RdrNameHsDecl
+ )
+import RnIfaces ( recordLocalSlurps )
+import RnHiFiles ( getTyClDeclBinders, loadInterface )
import RnEnv
import RnMonad
import FiniteMap
-import PrelMods
-import UniqFM ( UniqFM, emptyUFM, addListToUFM_C, lookupUFM )
-import Bag ( Bag, bagToList )
-import Maybes ( maybeToBool, expectJust )
-import Name
+import PrelNames ( pRELUDE_Name, mAIN_Name, main_RDR_Unqual, isUnboundName )
+import Module ( ModuleName, moduleName, WhereFrom(..) )
+import Name ( Name, nameSrcLoc, nameOccName )
+import NameSet
+import NameEnv
+import HscTypes ( Provenance(..), ImportReason(..), GlobalRdrEnv,
+ GenAvailInfo(..), AvailInfo, Avails, AvailEnv,
+ Deprecations(..), ModIface(..), emptyAvailEnv
+ )
+import RdrName ( rdrNameOcc, setRdrNameOcc )
+import OccName ( setOccNameSpace, dataName )
+import NameSet ( elemNameSet, emptyNameSet )
import Outputable
-import Util ( removeDups )
+import Maybes ( maybeToBool, catMaybes, mapMaybe )
+import ListSetOps ( removeDups )
+import Util ( sortLt )
+import List ( partition )
\end{code}
%************************************************************************
\begin{code}
-getGlobalNames :: RdrNameHsModule
- -> RnMG (Maybe (ExportEnv, RnEnv, NameSet, Name -> PrintUnqualified))
- -- The NameSet is the set of names that are
- -- either locally defined,
- -- or explicitly imported
- -- Nothing => no need to recompile
-
-getGlobalNames m@(HsModule this_mod _ exports imports _ _ mod_loc)
- = fixRn (\ ~(rec_exp_fn, _) ->
-
- -- PROCESS LOCAL DECLS
- -- Do these *first* so that the correct provenance gets
- -- into the global name cache.
- importsFromLocalDecls rec_exp_fn m `thenRn` \ (local_rn_env, local_mod_avails, local_avails) ->
-
- -- PROCESS IMPORT DECLS
- mapAndUnzip3Rn importsFromImportDecl all_imports
- `thenRn` \ (imp_rn_envs, imp_avails_s, explicit_imports_s) ->
-
- -- COMBINE RESULTS
- -- We put the local env second, so that a local provenance
- -- "wins", even if a module imports itself.
- foldlRn plusRnEnv emptyRnEnv imp_rn_envs `thenRn` \ imp_rn_env ->
- plusRnEnv imp_rn_env local_rn_env `thenRn` \ rn_env ->
-
- -- TRY FOR EARLY EXIT
- -- We can't go for an early exit before this because we have to check
- -- for name clashes. Consider:
- --
- -- module A where module B where
- -- import B h = True
- -- f = h
- --
- -- Suppose I've compiled everything up, and then I add a
- -- new definition to module B, that defines "f".
- --
- -- Then I must detect the name clash in A before going for an early
- -- exit. The early-exit code checks what's actually needed from B
- -- to compile A, and of course that doesn't include B.f. That's
- -- why we wait till after the plusRnEnv stuff to do the early-exit.
- checkEarlyExit this_mod `thenRn` \ up_to_date ->
- if up_to_date then
- returnRn (error "early exit", Nothing)
- else
-
-
- -- PROCESS EXPORT LISTS
- let
- export_avails :: ExportAvails
- export_avails = foldr plusExportAvails local_mod_avails imp_avails_s
-
- explicit_names :: NameSet -- locally defined or explicitly imported
- explicit_names = foldr add_on emptyNameSet (local_avails : explicit_imports_s)
- add_on avails names = foldr (unionNameSets . mkNameSet . availNames) names avails
- in
- exportsFromAvail this_mod exports export_avails rn_env
- `thenRn` \ (export_fn, export_env) ->
-
- -- RECORD THAT LOCALLY DEFINED THINGS ARE AVAILABLE
- mapRn (recordSlurp Nothing Compulsory) local_avails `thenRn_`
-
- -- BUILD THE "IMPORT FN". It just tells whether a name is in
- -- scope in an unqualified form.
- let
- print_unqual = mkImportFn imp_rn_env
- in
-
- returnRn (export_fn, Just (export_env, rn_env, explicit_names, print_unqual))
- ) `thenRn` \ (_, result) ->
- returnRn result
- where
- junk_exp_fn = error "RnNames:export_fn"
+getGlobalNames :: Module -> RdrNameHsModule
+ -> RnMG (GlobalRdrEnv, -- Maps all in-scope things
+ GlobalRdrEnv, -- Maps just *local* things
+ ExportAvails) -- The exported stuff
+
+getGlobalNames this_mod (HsModule _ _ _ imports decls _ mod_loc)
+ = -- PROCESS LOCAL DECLS
+ -- Do these *first* so that the correct provenance gets
+ -- into the global name cache.
+ importsFromLocalDecls this_mod decls `thenRn` \ (local_gbl_env, local_mod_avails) ->
+
+ -- PROCESS IMPORT DECLS
+ -- Do the non {- SOURCE -} ones first, so that we get a helpful
+ -- warning for {- SOURCE -} ones that are unnecessary
+ doptRn Opt_NoImplicitPrelude `thenRn` \ opt_no_prelude ->
+ let
+ all_imports = mk_prel_imports opt_no_prelude ++ imports
+ (source, ordinary) = partition is_source_import all_imports
+ is_source_import (ImportDecl _ ImportByUserSource _ _ _ _) = True
+ is_source_import other = False
+
+ get_imports = importsFromImportDecl this_mod_name
+ in
+ mapAndUnzipRn get_imports ordinary `thenRn` \ (imp_gbl_envs1, imp_avails_s1) ->
+ mapAndUnzipRn get_imports source `thenRn` \ (imp_gbl_envs2, imp_avails_s2) ->
+
+ -- COMBINE RESULTS
+ -- We put the local env second, so that a local provenance
+ -- "wins", even if a module imports itself.
+ let
+ gbl_env :: GlobalRdrEnv
+ imp_gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv (imp_gbl_envs2 ++ imp_gbl_envs1)
+ gbl_env = imp_gbl_env `plusGlobalRdrEnv` local_gbl_env
+
+ all_avails :: ExportAvails
+ all_avails = foldr plusExportAvails local_mod_avails (imp_avails_s2 ++ imp_avails_s1)
+ in
- all_imports = prel_imports ++ imports
+ -- ALL DONE
+ returnRn (gbl_env, local_gbl_env, all_avails)
+ where
+ this_mod_name = moduleName this_mod
-- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();
-- because the former doesn't even look at Prelude.hi for instance declarations,
-- whereas the latter does.
- prel_imports | this_mod == pRELUDE ||
- explicit_prelude_import ||
- opt_NoImplicitPrelude
- = []
-
- | otherwise = [ImportDecl pRELUDE
- False {- Not qualified -}
- HiFile {- Not source imported -}
- Nothing {- No "as" -}
- Nothing {- No import list -}
- mod_loc]
+ mk_prel_imports no_prelude
+ | this_mod_name == pRELUDE_Name ||
+ explicit_prelude_import ||
+ no_prelude
+ = []
+
+ | otherwise = [ImportDecl pRELUDE_Name
+ ImportByUser
+ False {- Not qualified -}
+ Nothing {- No "as" -}
+ Nothing {- No import list -}
+ mod_loc]
explicit_prelude_import
- = not (null [ () | (ImportDecl mod qual _ _ _ _) <- imports, mod == pRELUDE ])
+ = not (null [ () | (ImportDecl mod _ _ _ _ _) <- imports, mod == pRELUDE_Name ])
\end{code}
\begin{code}
-checkEarlyExit mod
- = checkErrsRn `thenRn` \ no_errs_so_far ->
- if not no_errs_so_far then
- -- Found errors already, so exit now
- returnRn True
- else
+importsFromImportDecl :: ModuleName
+ -> RdrNameImportDecl
+ -> RnMG (GlobalRdrEnv,
+ ExportAvails)
+
+importsFromImportDecl this_mod_name (ImportDecl imp_mod_name from qual_only as_mod import_spec iloc)
+ = pushSrcLocRn iloc $
- traceRn (text "Considering whether compilation is required...") `thenRn_`
- if not opt_SourceUnchanged then
- -- Source code changed and no errors yet... carry on
- traceRn (nest 4 (text "source file changed or recompilation check turned off")) `thenRn_`
- returnRn False
+ loadInterface (ppr imp_mod_name <+> ptext SLIT("is directly imported"))
+ imp_mod_name from `thenRn` \ iface ->
+ let
+ imp_mod = mi_module iface
+ avails_by_module = mi_exports iface
+ deprecs = mi_deprecs iface
+
+ avails :: Avails
+ avails = [ avail | (mod_name, avails) <- avails_by_module,
+ mod_name /= this_mod_name,
+ avail <- avails ]
+ -- 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
+ -- import B( AType )
+ -- type AType = ...
+ --
+ -- module B( AType ) where
+ -- import {-# SOURCE #-} A( AType )
+ --
+ -- then you'll get a 'B does not export AType' message. Oh well.
+
+ in
+ if null avails_by_module then
+ -- If there's an error in loadInterface, (e.g. interface
+ -- file not found) we get lots of spurious errors from 'filterImports'
+ returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name)
else
- -- Unchanged source, and no errors yet; see if usage info
- -- up to date, and exit if so
- checkUpToDate mod `thenRn` \ up_to_date ->
- putDocRn (text "Compilation" <+>
- text (if up_to_date then "IS NOT" else "IS") <+>
- text "required") `thenRn_`
- returnRn up_to_date
-\end{code}
-
-\begin{code}
-importsFromImportDecl :: RdrNameImportDecl
- -> RnMG (RnEnv, ExportAvails, [AvailInfo])
+ -- Complain if we import a deprecated module
+ ifOptRn Opt_WarnDeprecations (
+ case deprecs of
+ DeprecAll txt -> addWarnRn (moduleDeprec imp_mod_name txt)
+ other -> returnRn ()
+ ) `thenRn_`
+
+ -- Filter the imports according to the import list
+ filterImports imp_mod_name from import_spec avails `thenRn` \ (filtered_avails, explicits) ->
-importsFromImportDecl (ImportDecl mod qual_only as_source as_mod import_spec loc)
- = pushSrcLocRn loc $
- getInterfaceExports mod as_source `thenRn` \ (avails, fixities) ->
- filterImports mod import_spec avails `thenRn` \ (filtered_avails, hides, explicits) ->
let
- how_in_scope = FromImportDecl mod loc
+ unqual_imp = not qual_only -- Maybe want unqualified names
+ qual_mod = case as_mod of
+ Nothing -> imp_mod_name
+ Just another_name -> another_name
+
+ mk_prov name = NonLocalDef (UserImport imp_mod iloc (name `elemNameSet` explicits))
+ gbl_env = mkGlobalRdrEnv qual_mod unqual_imp mk_prov filtered_avails deprecs
+ exports = mkExportAvails qual_mod unqual_imp gbl_env filtered_avails
in
- qualifyImports mod
- True -- Want qualified names
- (not qual_only) -- Maybe want unqualified names
- as_mod
- hides
- filtered_avails (\n -> how_in_scope)
- [ (occ,(fixity,how_in_scope)) | (occ,fixity) <- fixities ]
- `thenRn` \ (rn_env, mod_avails) ->
- returnRn (rn_env, mod_avails, explicits)
+ returnRn (gbl_env, exports)
\end{code}
\begin{code}
-importsFromLocalDecls rec_exp_fn (HsModule mod _ _ _ fix_decls decls _)
- = foldlRn getLocalDeclBinders [] decls `thenRn` \ avails ->
- mapRn fixityFromFixDecl fix_decls `thenRn` \ fixities ->
- qualifyImports mod
- False -- Don't want qualified names
- True -- Want unqualified names
- Nothing -- No "as M" part
- [] -- Hide nothing
- avails (\n -> FromLocalDefn (getSrcLoc n))
- fixities
- `thenRn` \ (rn_env, mod_avails) ->
- returnRn (rn_env, mod_avails, avails)
+importsFromLocalDecls this_mod decls
+ = mapRn (getLocalDeclBinders this_mod) decls `thenRn` \ avails_s ->
+ -- The avails that are returned don't include the "system" names
+ let
+ avails = concat avails_s
+
+ all_names :: [Name] -- All the defns; no dups eliminated
+ all_names = [name | avail <- avails, name <- availNames avail]
+
+ dups :: [[Name]]
+ (_, dups) = removeDups compare all_names
+ in
+ -- Check for duplicate definitions
+ -- The complaint will come out as "Multiple declarations of Foo.f" because
+ -- since 'f' is in the env twice, the unQualInScope used by the error-msg
+ -- printer returns False. It seems awkward to fix, unfortunately.
+ mapRn_ (addErrRn . dupDeclErr) dups `thenRn_`
+
+
+ -- Record that locally-defined things are available
+ recordLocalSlurps (availsToNameSet avails) `thenRn_`
+ let
+ mod_name = moduleName this_mod
+ unqual_imp = True -- Want unqualified names
+ mk_prov n = LocalDef -- Provenance is local
+
+ gbl_env = mkGlobalRdrEnv mod_name unqual_imp mk_prov avails NoDeprecs
+ -- NoDeprecs: don't complain about locally defined names
+ -- For a start, we may be exporting a deprecated thing
+ -- Also we may use a deprecated thing in the defn of another
+ -- deprecated things. We may even use a deprecated thing in
+ -- the defn of a non-deprecated thing, when changing a module's
+ -- interface
+
+ exports = mkExportAvails mod_name unqual_imp gbl_env avails
+ in
+ returnRn (gbl_env, exports)
+
+---------------------------
+getLocalDeclBinders :: Module -> RdrNameHsDecl -> RnMG [AvailInfo]
+getLocalDeclBinders mod (TyClD tycl_decl)
+ = -- For type and class decls, we generate Global names, with
+ -- no export indicator. They need to be global because they get
+ -- permanently bound into the TyCons and Classes. They don't need
+ -- an export indicator because they are all implicitly exported.
+ getTyClDeclBinders mod tycl_decl `thenRn` \ (avail, sys_names) ->
+
+ -- Record that the system names are available
+ recordLocalSlurps (mkNameSet sys_names) `thenRn_`
+ returnRn [avail]
+
+getLocalDeclBinders mod (ValD binds)
+ = mapRn new (collectLocatedHsBinders binds) `thenRn` \ avails ->
+ returnRn avails
where
- newLocalName rdr_name loc
- = newLocallyDefinedGlobalName mod (rdrNameOcc rdr_name) rec_exp_fn loc
-
- getLocalDeclBinders avails (ValD binds)
- = mapRn do_one (bagToList (collectTopBinders binds)) `thenRn` \ val_avails ->
- returnRn (val_avails ++ avails)
-
- getLocalDeclBinders avails decl
- = getDeclBinders newLocalName decl `thenRn` \ avail ->
- case avail of
- NotAvailable -> returnRn avails -- Instance decls and suchlike
- other -> returnRn (avail : avails)
-
- do_one (rdr_name, loc)
- = newLocalName rdr_name loc `thenRn` \ name ->
- returnRn (Avail name)
+ new (rdr_name, loc) = newTopBinder mod rdr_name loc `thenRn` \ name ->
+ returnRn (Avail name)
+
+getLocalDeclBinders mod (ForD (ForeignImport nm _ _ _ loc))
+ = newTopBinder mod nm loc `thenRn` \ name ->
+ returnRn [Avail name]
+getLocalDeclBinders mod (ForD _)
+ = returnRn []
+
+getLocalDeclBinders mod (FixD _) = returnRn []
+getLocalDeclBinders mod (DeprecD _) = returnRn []
+getLocalDeclBinders mod (DefD _) = returnRn []
+getLocalDeclBinders mod (InstD _) = returnRn []
+getLocalDeclBinders mod (RuleD _) = returnRn []
\end{code}
+
%************************************************************************
%* *
\subsection{Filtering imports}
available, and filters it through the import spec (if any).
\begin{code}
-filterImports :: Module
- -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hidin
- -> [AvailInfo] -- What's available
- -> RnMG ([AvailInfo], -- What's actually imported
- [AvailInfo], -- What's to be hidden (the unqualified version, that is)
- [AvailInfo]) -- What was imported explicitly
+filterImports :: ModuleName -- The module being imported
+ -> WhereFrom -- Tells whether it's a {-# SOURCE #-} import
+ -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding
+ -> [AvailInfo] -- What's available
+ -> RnMG ([AvailInfo], -- What's imported
+ NameSet) -- What was imported explicitly
-- Complains if import spec mentions things that the module doesn't export
-- Warns/informs if import spec contains duplicates.
-filterImports mod Nothing imports
- = returnRn (imports, [], [])
-
-filterImports mod (Just (want_hiding, import_items)) avails
- = mapRn check_item import_items `thenRn` \ item_avails ->
- if want_hiding
- then
- returnRn (avails, item_avails, []) -- All imported; item_avails to be hidden
- else
- returnRn (item_avails, [], item_avails) -- Just item_avails imported; nothing to be hidden
+filterImports mod from Nothing imports
+ = returnRn (imports, emptyNameSet)
+filterImports mod from (Just (want_hiding, import_items)) total_avails
+ = flatMapRn get_item import_items `thenRn` \ avails_w_explicits ->
+ let
+ (item_avails, explicits_s) = unzip avails_w_explicits
+ explicits = foldl addListToNameSet emptyNameSet explicits_s
+ in
+ if want_hiding then
+ let -- All imported; item_avails to be hidden
+ hidden = availsToNameSet item_avails
+ keep n = not (n `elemNameSet` hidden)
+ in
+ returnRn (pruneAvails keep total_avails, emptyNameSet)
+ else
+ -- Just item_avails imported; nothing to be hidden
+ returnRn (item_avails, explicits)
where
import_fm :: FiniteMap OccName AvailInfo
import_fm = listToFM [ (nameOccName name, avail)
- | avail <- avails,
- name <- availEntityNames avail]
+ | avail <- total_avails,
+ name <- availNames avail]
+ -- Even though availNames returns data constructors too,
+ -- they won't make any difference because naked entities like T
+ -- in an import list map to TcOccs, not VarOccs.
+
+ bale_out item = addErrRn (badImportItemErr mod from item) `thenRn_`
+ returnRn []
+
+ get_item :: RdrNameIE -> RnMG [(AvailInfo, [Name])]
+ -- Empty list for a bad item.
+ -- Singleton is typical case.
+ -- Can have two when we are hiding, and mention C which might be
+ -- both a class and a data constructor.
+ -- The [Name] is the list of explicitly-mentioned names
+ get_item item@(IEModuleContents _) = bale_out item
+
+ get_item item@(IEThingAll _)
+ = case check_item item of
+ Nothing -> bale_out item
+ Just avail@(AvailTC _ [n]) -> -- This occurs when you import T(..), but
+ -- only export T abstractly. The single [n]
+ -- in the AvailTC is the type or class itself
+ ifOptRn Opt_WarnMisc (addWarnRn (dodgyImportWarn mod item)) `thenRn_`
+ returnRn [(avail, [availName avail])]
+ Just avail -> returnRn [(avail, [availName avail])]
+
+ get_item item@(IEThingAbs n)
+ | want_hiding -- hiding( C )
+ -- Here the 'C' can be a data constructor *or* a type/class
+ = case catMaybes [check_item item, check_item (IEVar data_n)] of
+ [] -> bale_out item
+ avails -> returnRn [(a, []) | a <- avails]
+ -- The 'explicits' list is irrelevant when hiding
+ where
+ data_n = setRdrNameOcc n (setOccNameSpace (rdrNameOcc n) dataName)
- check_item item@(IEModuleContents _)
- = addErrRn (badImportItemErr mod item) `thenRn_`
- returnRn NotAvailable
+ get_item item
+ = case check_item item of
+ Nothing -> bale_out item
+ Just avail -> returnRn [(avail, availNames avail)]
check_item item
| not (maybeToBool maybe_in_import_avails) ||
- (case filtered_avail of { NotAvailable -> True; other -> False })
- = addErrRn (badImportItemErr mod item) `thenRn_`
- returnRn NotAvailable
+ not (maybeToBool maybe_filtered_avail)
+ = Nothing
- | otherwise = returnRn filtered_avail
+ | otherwise
+ = Just filtered_avail
where
- maybe_in_import_avails = lookupFM import_fm (ieOcc item)
+ wanted_occ = rdrNameOcc (ieName item)
+ maybe_in_import_avails = lookupFM import_fm wanted_occ
+
Just avail = maybe_in_import_avails
- filtered_avail = filterAvail item avail
+ maybe_filtered_avail = filterAvail item avail
+ Just filtered_avail = maybe_filtered_avail
\end{code}
%* *
%************************************************************************
-@qualifyImports@ takes the @ExportEnv@ after filtering through the import spec
-of an import decl, and deals with producing an @RnEnv@ with the
-right qualified names. It also turns the @Names@ in the @ExportEnv@ into
-fully fledged @Names@.
-
\begin{code}
-qualifyImports :: Module -- Imported module
- -> Bool -- True <=> want qualified import
- -> Bool -- True <=> want unqualified import
- -> Maybe Module -- Optional "as M" part
- -> [AvailInfo] -- What's to be hidden
- -> Avails -> (Name -> HowInScope) -- Whats imported and how
- -> [(OccName, (Fixity, HowInScope))] -- Ditto for fixities
- -> RnMG (RnEnv, ExportAvails)
-
-qualifyImports this_mod qual_imp unqual_imp as_mod hides
- avails name_to_his fixities
- =
- -- Make the name environment. Even though we're talking about a
- -- single import module there might still be name clashes,
- -- because it might be the module being compiled.
- foldlRn add_avail emptyGlobalNameEnv avails `thenRn` \ name_env1 ->
- let
- -- Delete things that are hidden
- name_env2 = foldl del_avail name_env1 hides
-
- -- Create the fixity env
- fixity_env = foldl (add_fixity name_env2) emptyFixityEnv fixities
-
- -- Create the export-availability info
- export_avails = mkExportAvails unqual_imp qual_mod avails
- in
- returnRn (RnEnv name_env2 fixity_env, export_avails)
+type ExportAvails
+ = (FiniteMap ModuleName Avails,
+ -- Used to figure out "module M" export specifiers
+ -- Includes avails only from *unqualified* imports
+ -- (see 1.4 Report Section 5.1.1)
+
+ AvailEnv) -- All the things that are available.
+ -- Its domain is all the "main" things;
+ -- i.e. *excluding* class ops and constructors
+ -- (which appear inside their parent AvailTC)
+
+mkEmptyExportAvails :: ModuleName -> ExportAvails
+mkEmptyExportAvails mod_name = (unitFM mod_name [], emptyNameEnv)
+
+plusExportAvails :: ExportAvails -> ExportAvails -> ExportAvails
+plusExportAvails (m1, e1) (m2, e2) = (plusFM_C (++) m1 m2, plusAvailEnv e1 e2)
+
+mkExportAvails :: ModuleName -> Bool -> GlobalRdrEnv -> [AvailInfo] -> ExportAvails
+mkExportAvails mod_name unqual_imp gbl_env avails
+ = (mod_avail_env, entity_avail_env)
where
- qual_mod = case as_mod of
- Nothing -> this_mod
- Just another_name -> another_name
-
- add_avail :: GlobalNameEnv -> AvailInfo -> RnMG GlobalNameEnv
- add_avail env avail = foldlRn add_name env (availNames avail)
- add_name env name = add qual_imp env (Qual qual_mod occ err_hif) `thenRn` \ env1 ->
- add unqual_imp env1 (Unqual occ)
- where
- add False env rdr_name = returnRn env
- add True env rdr_name = addOneToGlobalNameEnv env rdr_name (name, name_to_his name)
- occ = nameOccName name
-
- del_avail env avail = foldl delOneFromGlobalNameEnv env rdr_names
- where
- rdr_names = map (Unqual . nameOccName) (availNames avail)
-
- add_fixity name_env fix_env (occ_name, fixity)
- = add qual $ add unqual $ fix_env
- where
- qual = Qual qual_mod occ_name err_hif
- unqual = Unqual occ_name
-
- add rdr_name fix_env | maybeToBool (lookupFM name_env rdr_name)
- = addOneToFixityEnv fix_env rdr_name fixity
- | otherwise
- = fix_env
-
-err_hif = error "qualifyImports: hif" -- Not needed in key to mapping
+ mod_avail_env = unitFM mod_name unqual_avails
+
+ -- 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.
+
+ unqual_avails | not unqual_imp = [] -- Short cut when no unqualified imports
+ | otherwise = pruneAvails (unQualInScope gbl_env) avails
+
+ entity_avail_env = foldl insert emptyAvailEnv avails
+ insert env avail = extendNameEnv_C plusAvail env (availName avail) avail
+ -- '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
\end{code}
-unQualify adds an Unqual binding for every existing Qual binding.
-
-\begin{code}
-unQualify :: FiniteMap RdrName elt -> FiniteMap RdrName elt
-unQualify fm = addListToFM fm [(Unqual occ, elt) | (Qual _ occ _, elt) <- fmToList fm]
-\end{code}
%************************************************************************
%* *
-\subsection{Local declarations}
+\subsection{Export list processing}
%* *
%************************************************************************
-
-\begin{code}
-fixityFromFixDecl :: RdrNameFixityDecl -> RnMG (OccName, (Fixity, HowInScope))
-
-fixityFromFixDecl (FixityDecl rdr_name fixity loc)
- = returnRn (rdrNameOcc rdr_name, (fixity, FromLocalDefn loc))
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{Export list processing
-%* *
-%************************************************************************
-
-The @AvailEnv@ type is just used internally in @exportsFromAvail@.
-When exporting we need to combine the availabilities for a particular
-exported thing, and we also need to check for name clashes -- that
-is: two exported things must have different @OccNames@.
-
-\begin{code}
-type AvailEnv = FiniteMap OccName (RdrNameIE, AvailInfo, Int{-no. of clashes-})
- -- The FM maps each OccName to the RdrNameIE that gave rise to it,
- -- for error reporting, as well as to its AvailInfo
-
-emptyAvailEnv = emptyFM
-
-{-
- Add new entry to environment. Checks for name clashes, i.e.,
- plain duplicates or exported entity pairs that have different OccNames.
- (c.f. 5.1.1 of Haskell 1.4 report.)
--}
-addAvailEnv :: Bool -> RdrNameIE -> AvailEnv -> AvailInfo -> RnM s d AvailEnv
-addAvailEnv warn_dups ie env NotAvailable = returnRn env
-addAvailEnv warn_dups ie env (AvailTC _ []) = returnRn env
-addAvailEnv warn_dups ie env avail
- | warn_dups = mapMaybeRn (addErrRn . availClashErr) () conflict `thenRn_`
- returnRn (addToFM_C add_avail env key elt)
- | otherwise = returnRn (addToFM_C add_avail env key elt)
- where
- key = nameOccName (availName avail)
- elt = (ie,avail,reports_on)
-
- reports_on
- | maybeToBool dup = 1
- | otherwise = 0
-
- conflict = conflictFM bad_avail env key elt
- dup
- | warn_dups = conflictFM dup_avail env key elt
- | otherwise = Nothing
-
-addListToAvailEnv :: AvailEnv -> RdrNameIE -> [AvailInfo] -> RnM s d AvailEnv
-addListToAvailEnv env ie items = foldlRn (addAvailEnv False ie) env items
-
-bad_avail (ie1,avail1,r1) (ie2,avail2,r2)
- = availName avail1 /= availName avail2 -- Same OccName, different Name
-dup_avail (ie1,avail1,r1) (ie2,avail2,r2)
- = availName avail1 == availName avail2 -- Same OccName & avail.
-
-add_avail (ie1,a1,r1) (ie2,a2,r2) = (ie1, a1 `plusAvail` a2, r1 + r2)
-\end{code}
-
Processing the export list.
-You might think that we should record things that appear in the export list as
-``occurrences'' (using addOccurrenceName), but you'd be wrong. We do check (here)
-that they are in scope, but there is no need to slurp in their actual declaration
-(which is what addOccurrenceName forces). Indeed, doing so would big trouble when
-compiling PrelBase, because it re-exports GHC, which includes takeMVar#, whose type
-includes ConcBase.StateAndSynchVar#, and so on...
+You might think that we should record things that appear in the export list
+as ``occurrences'' (using @addOccurrenceName@), but you'd be wrong.
+We do check (here) that they are in scope,
+but there is no need to slurp in their actual declaration
+(which is what @addOccurrenceName@ forces).
+
+Indeed, doing so would big trouble when
+compiling @PrelBase@, because it re-exports @GHC@, which includes @takeMVar#@,
+whose type includes @ConcBase.StateAndSynchVar#@, and so on...
\begin{code}
-exportsFromAvail :: Module
- -> Maybe [RdrNameIE] -- Export spec
- -> ExportAvails
- -> RnEnv
- -> RnMG (Name -> ExportFlag, ExportEnv)
+type ExportAccum -- The type of the accumulating parameter of
+ -- the main worker function in exportsFromAvail
+ = ([ModuleName], -- 'module M's seen so far
+ ExportOccMap, -- Tracks exported occurrence names
+ AvailEnv) -- The accumulated exported stuff, kept in an env
+ -- so we can common-up related AvailInfos
+
+type ExportOccMap = FiniteMap OccName (Name, RdrNameIE)
+ -- Tracks what a particular exported OccName
+ -- in an export list refers to, and which item
+ -- it came from. It's illegal to export two distinct things
+ -- that have the same occurrence name
+
+
+exportsFromAvail :: ModuleName
+ -> Maybe [RdrNameIE] -- Export spec
+ -> FiniteMap ModuleName Avails -- Used for (module M) exports
+ -> NameEnv AvailInfo -- Domain is every in-scope thing
+ -> GlobalRdrEnv
+ -> RnMG Avails
-- Complains if two distinct exports have same OccName
-- Warns about identical exports.
-- Complains about exports items not in scope
-exportsFromAvail this_mod Nothing export_avails rn_env
- = exportsFromAvail this_mod (Just [IEModuleContents this_mod]) export_avails rn_env
+exportsFromAvail this_mod Nothing
+ mod_avail_env entity_avail_env global_name_env
+ = exportsFromAvail this_mod true_exports mod_avail_env entity_avail_env global_name_env
+ where
+ true_exports = Just $ if this_mod == mAIN_Name
+ then [IEVar main_RDR_Unqual]
+ -- export Main.main *only* unless otherwise specified,
+ else [IEModuleContents this_mod]
+ -- but for all other modules export everything.
exportsFromAvail this_mod (Just export_items)
- (mod_avail_env, entity_avail_env)
- (RnEnv global_name_env fixity_env)
- = checkForModuleExportDups export_items `thenRn` \ export_items' ->
- foldlRn exports_from_item emptyAvailEnv export_items' `thenRn` \ export_avail_env ->
+ mod_avail_env entity_avail_env global_name_env
+ = doptRn Opt_WarnDuplicateExports `thenRn` \ warn_dup_exports ->
+ foldlRn (exports_from_item warn_dup_exports)
+ ([], emptyFM, emptyAvailEnv) export_items
+ `thenRn` \ (_, _, export_avail_map) ->
let
- dup_entries = fmToList (filterFM (\ _ (_,_,clashes) -> clashes > 0) export_avail_env)
+ export_avails :: [AvailInfo]
+ export_avails = nameEnvElts export_avail_map
in
- mapRn (addWarnRn . dupExportWarn) dup_entries `thenRn_`
- let
- export_avails = map (\ (_,a,_) -> a) (eltsFM export_avail_env)
- export_fixities = mk_exported_fixities (availsToNameSet export_avails)
- export_fn = mk_export_fn export_avails
- in
- returnRn (export_fn, ExportEnv export_avails export_fixities)
+ returnRn export_avails
where
- exports_from_item :: AvailEnv -> RdrNameIE -> RnMG AvailEnv
- exports_from_item export_avail_env ie@(IEModuleContents mod)
+ exports_from_item :: Bool -> ExportAccum -> RdrNameIE -> RnMG ExportAccum
+
+ exports_from_item warn_dups acc@(mods, occs, avails) ie@(IEModuleContents mod)
+ | mod `elem` mods -- Duplicate export of M
+ = warnCheckRn warn_dups (dupModuleExport mod) `thenRn_`
+ returnRn acc
+
+ | otherwise
= case lookupFM mod_avail_env mod of
- Nothing -> failWithRn export_avail_env (modExportErr mod)
- Just avails -> addListToAvailEnv export_avail_env ie avails
-
- exports_from_item export_avail_env ie
- | not (maybeToBool maybe_in_scope)
- = failWithRn export_avail_env (unknownNameErr (ieName ie))
-
-#ifdef DEBUG
- -- I can't see why this should ever happen; if the thing is in scope
- -- at all it ought to have some availability
- | not (maybeToBool maybe_avail)
- = pprTrace "exportsFromAvail: curious Nothing:" (ppr name)
- returnRn export_avail_env
-#endif
-
- | not enough_avail
- = failWithRn export_avail_env (exportItemErr ie export_avail)
-
- | otherwise -- Phew! It's OK!
- = addAvailEnv opt_WarnDuplicateExports ie export_avail_env export_avail
- where
- maybe_in_scope = lookupFM global_name_env (ieName ie)
- Just (name,_) = maybe_in_scope
- maybe_avail = lookupUFM entity_avail_env name
- Just avail = maybe_avail
- export_avail = filterAvail ie avail
- enough_avail = case export_avail of {NotAvailable -> False; other -> True}
-
- -- We export a fixity iff we export a thing with the same (qualified) RdrName
- mk_exported_fixities :: NameSet -> [(OccName, Fixity)]
- mk_exported_fixities exports
- = fmToList (foldr (perhaps_add_fixity exports)
- emptyFM
- (fmToList fixity_env))
-
- perhaps_add_fixity :: NameSet -> (RdrName, (Fixity, HowInScope))
- -> FiniteMap OccName Fixity
- -> FiniteMap OccName Fixity
- perhaps_add_fixity exports (rdr_name, (fixity, how_in_scope)) fix_env
- = let
- do_nothing = fix_env -- The default is to pass on the env unchanged
- in
- -- Step 1: check whether the rdr_name is in scope; if so find its Name
- case lookupFM global_name_env rdr_name of {
- Nothing -> do_nothing;
- Just (fixity_name,_) ->
-
- -- Step 2: check whether the fixity thing is exported
- if not (fixity_name `elemNameSet` exports) then
- do_nothing
- else
-
- -- Step 3: check whether we already have a fixity for the
- -- Name's OccName in the fix_env we are building up. This can easily
- -- happen. the original fixity_env might contain bindings for
- -- M.a and N.a, if a was imported via M and N.
- -- If this does happen, we expect the fixity to be the same either way.
- let
- occ_name = rdrNameOcc rdr_name
- in
- case lookupFM fix_env occ_name of {
- Just fixity1 -> -- Got it already
- ASSERT( fixity == fixity1 )
- do_nothing;
- Nothing ->
-
- -- Step 3: add it to the outgoing fix_env
- addToFM fix_env occ_name fixity
- }}
-
-{- warn and weed out duplicate module entries from export list. -}
-checkForModuleExportDups :: [RdrNameIE] -> RnMG [RdrNameIE]
-checkForModuleExportDups ls
- | opt_WarnDuplicateExports = check_modules ls
- | otherwise = returnRn ls
- where
- -- NOTE: reorders the export list by moving all module-contents
- -- exports to the end (removing duplicates in the process.)
- check_modules ls =
- (case dups of
- [] -> returnRn ()
- ls -> mapRn (\ ds@(IEModuleContents x:_) ->
- addWarnRn (dupModuleExport x (length ds))) ls `thenRn_`
- returnRn ()) `thenRn_`
- returnRn (ls_no_modules ++ no_module_dups)
- where
- (ls_no_modules,modules) = foldr split_mods ([],[]) ls
-
- split_mods i@(IEModuleContents _) ~(no_ms,ms) = (no_ms,i:ms)
- split_mods i ~(no_ms,ms) = (i:no_ms,ms)
-
- (no_module_dups, dups) = removeDups cmp_mods modules
-
- cmp_mods (IEModuleContents m1) (IEModuleContents m2) = m1 `compare` m2
-
-mk_export_fn :: [AvailInfo] -> (Name -> ExportFlag)
-mk_export_fn avails
- = \name -> if name `elemNameSet` exported_names
- then Exported
- else NotExported
+ Nothing -> failWithRn acc (modExportErr mod)
+ Just mod_avails -> foldlRn (check_occs ie) occs mod_avails
+ `thenRn` \ occs' ->
+ let
+ avails' = foldl addAvail avails mod_avails
+ in
+ returnRn (mod:mods, occs', avails')
+
+ exports_from_item warn_dups acc@(mods, occs, avails) ie
+ = lookupSrcName global_name_env (ieName ie) `thenRn` \ name ->
+
+ -- See what's available in the current environment
+ case lookupNameEnv entity_avail_env name of {
+ Nothing -> -- Presumably this happens because lookupSrcName didn't find
+ -- the name and returned an unboundName, which won't be in
+ -- the entity_avail_env, of course
+ WARN( not (isUnboundName name), ppr name )
+ returnRn acc ;
+
+ Just avail ->
+
+ -- Filter out the bits we want
+ case filterAvail ie avail of {
+ Nothing -> -- Not enough availability
+ failWithRn acc (exportItemErr ie) ;
+
+ Just export_avail ->
+
+ -- Phew! It's OK! Now to check the occurrence stuff!
+ warnCheckRn (ok_item ie avail) (dodgyExportWarn ie) `thenRn_`
+ check_occs ie occs export_avail `thenRn` \ occs' ->
+ returnRn (mods, occs', addAvail avails export_avail)
+ }}
+
+
+
+ok_item (IEThingAll _) (AvailTC _ [n]) = False
+ -- This occurs when you import T(..), but
+ -- only export T abstractly. The single [n]
+ -- in the AvailTC is the type or class itself
+ok_item _ _ = True
+
+check_occs :: RdrNameIE -> ExportOccMap -> AvailInfo -> RnMG ExportOccMap
+check_occs ie occs avail
+ = doptRn Opt_WarnDuplicateExports `thenRn` \ warn_dup_exports ->
+ foldlRn (check warn_dup_exports) occs (availNames avail)
where
- exported_names :: NameSet
- exported_names = availsToNameSet avails
+ check warn_dup occs name
+ = case lookupFM occs name_occ of
+ Nothing -> returnRn (addToFM occs name_occ (name, ie))
+ Just (name', ie')
+ | name == name' -> -- Duplicate export
+ warnCheckRn warn_dup
+ (dupExportWarn name_occ ie ie')
+ `thenRn_` returnRn occs
+
+ | otherwise -> -- Same occ name but different names: an error
+ failWithRn occs (exportClashErr name_occ ie ie')
+ where
+ name_occ = nameOccName name
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-badImportItemErr mod ie
- = sep [ptext SLIT("Module"), quotes (pprModule mod),
+badImportItemErr mod from ie
+ = sep [ptext SLIT("Module"), quotes (ppr mod), source_import,
ptext SLIT("does not export"), quotes (ppr ie)]
-
+ where
+ source_import = case from of
+ ImportByUserSource -> ptext SLIT("(hi-boot interface)")
+ other -> empty
+
+dodgyImportWarn mod item = dodgyMsg (ptext SLIT("import")) item
+dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) item
+
+dodgyMsg kind item@(IEThingAll tc)
+ = sep [ ptext SLIT("The") <+> kind <+> ptext SLIT("item") <+> quotes (ppr 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 (pprModule mod)]
+ = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (ppr mod)]
-exportItemErr export_item NotAvailable
- = sep [ ptext SLIT("Export item not in scope:"), quotes (ppr export_item)]
+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") ]
-exportItemErr export_item avail
- = hang (ptext SLIT("Export item not fully in scope:"))
- 4 (vcat [hsep [ptext SLIT("Wanted: "), ppr export_item],
- hsep [ptext SLIT("Available:"), ppr (ieOcc export_item), pprAvail avail]])
+exportClashErr occ_name ie1 ie2
+ = hsep [ptext SLIT("The export items"), quotes (ppr ie1)
+ ,ptext SLIT("and"), quotes (ppr ie2)
+ ,ptext SLIT("create conflicting exports for"), quotes (ppr occ_name)]
-availClashErr (occ_name, ((ie1,avail1,_), (ie2,avail2,_)))
- = hsep [ptext SLIT("The export items"), quotes (ppr ie1), ptext SLIT("and"), quotes (ppr ie2),
- ptext SLIT("create conflicting exports for"), quotes (ppr occ_name)]
+dupDeclErr (n:ns)
+ = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),
+ nest 4 (vcat (map ppr sorted_locs))]
+ where
+ sorted_locs = sortLt occ'ed_before (map nameSrcLoc (n:ns))
+ occ'ed_before a b = LT == compare a b
-dupExportWarn (occ_name, (_,_,times))
+dupExportWarn occ_name ie1 ie2
= hsep [quotes (ppr occ_name),
- ptext SLIT("mentioned"), speakNTimes (times+1),
- ptext SLIT("in export list")]
+ ptext SLIT("is exported by"), quotes (ppr ie1),
+ ptext SLIT("and"), quotes (ppr ie2)]
-dupModuleExport mod times
- = hsep [ptext SLIT("Module"), quotes (pprModule mod),
- ptext SLIT("mentioned"), speakNTimes times,
+dupModuleExport mod
+ = hsep [ptext SLIT("Duplicate"),
+ quotes (ptext SLIT("Module") <+> ppr mod),
ptext SLIT("in export list")]
-\end{code}
+moduleDeprec mod txt
+ = sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"),
+ nest 4 (ppr txt) ]
+\end{code}
projects / ghc-hetmet.git / blobdiff