-%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
-%
-\section[RnNames]{Extracting imported and top-level names in scope}
-
-\begin{code}
-module RnNames (
- getGlobalNames
- ) where
-
-#include "HsVersions.h"
-
-import CmdLineOpts ( opt_NoImplicitPrelude, opt_WarnDuplicateExports,
- opt_SourceUnchanged, opt_WarnUnusedBinds
- )
-
-import HsSyn ( HsModule(..), HsDecl(..), TyClDecl(..),
- IE(..), ieName,
- ForeignDecl(..), ForKind(..), isDynamic,
- FixitySig(..), Sig(..), ImportDecl(..),
- collectTopBinders
- )
-import RdrHsSyn ( RdrNameIE, RdrNameImportDecl,
- RdrNameHsModule, RdrNameHsDecl
- )
-import RnIfaces ( getInterfaceExports, getDeclBinders,
- recordSlurp, checkUpToDate
- )
-import RnEnv
-import RnMonad
-
-import FiniteMap
-import PrelMods
-import PrelInfo ( main_RDR )
-import UniqFM ( lookupUFM )
-import Bag ( bagToList )
-import Maybes ( maybeToBool )
-import Module ( ModuleName, mkThisModule, pprModuleName, WhereFrom(..) )
-import NameSet
-import Name ( Name, ExportFlag(..), ImportReason(..), Provenance(..),
- isLocallyDefined, setNameProvenance,
- nameOccName, getSrcLoc, pprProvenance, getNameProvenance
- )
-import RdrName ( RdrName, rdrNameOcc, mkRdrQual, mkRdrUnqual, isQual )
-import SrcLoc ( SrcLoc )
-import NameSet ( elemNameSet, emptyNameSet )
-import Outputable
-import Unique ( getUnique )
-import Util ( removeDups, equivClassesByUniq, sortLt )
-import List ( partition )
-\end{code}
-
-
-
-%************************************************************************
-%* *
-\subsection{Get global names}
-%* *
-%************************************************************************
-
-\begin{code}
-getGlobalNames :: RdrNameHsModule
- -> RnMG (Maybe (ExportEnv,
- GlobalRdrEnv,
- FixityEnv, -- Fixities for local decls only
- NameEnv AvailInfo -- Maps a name to its parent AvailInfo
- -- Just for in-scope things only
- ))
- -- Nothing => no need to recompile
-
-getGlobalNames (HsModule this_mod _ exports imports decls mod_loc)
- = -- These two fix-loops are to get the right
- -- provenance information into a Name
- fixRn (\ ~(rec_gbl_env, rec_exported_avails, _) ->
-
--- fixRn (\ ~(rec_rn_env, _) ->
- let
- rec_unqual_fn :: Name -> Bool -- Is this chap in scope unqualified?
- rec_unqual_fn = unQualInScope rec_gbl_env
-
- rec_exp_fn :: Name -> ExportFlag
- rec_exp_fn = mk_export_fn (availsToNameSet rec_exported_avails)
- in
--- setOmitQualFn rec_unqual_fn $
- setModuleRn this_mod $
-
- -- PROCESS LOCAL DECLS
- -- Do these *first* so that the correct provenance gets
- -- into the global name cache.
- importsFromLocalDecls this_mod rec_exp_fn 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
- let
- (source, ordinary) = partition is_source_import all_imports
- is_source_import (ImportDecl _ ImportByUserSource _ _ _ _) = True
- is_source_import other = False
- in
- mapAndUnzipRn (importsFromImportDecl rec_unqual_fn) ordinary `thenRn` \ (imp_gbl_envs1, imp_avails_s1) ->
- mapAndUnzipRn (importsFromImportDecl rec_unqual_fn) 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
--- returnRn (gbl_env, all_avails)
--- ) `thenRn` \ (gbl_env, all_avails) ->
-
- -- 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 plusEnv stuff to do the early-exit.
- checkEarlyExit this_mod `thenRn` \ up_to_date ->
- if up_to_date then
- returnRn (gbl_env, junk_exp_fn, Nothing)
- else
-
- -- RECORD BETTER PROVENANCES IN THE CACHE
- -- The names in the envirnoment have better provenances (e.g. imported on line x)
- -- than the names in the name cache. We update the latter now, so that we
- -- we start renaming declarations we'll get the good names
- -- The isQual is because the qualified name is always in scope
- updateProvenances (concat [names | (rdr_name, names) <- rdrEnvToList imp_gbl_env,
- isQual rdr_name]) `thenRn_`
-
- -- PROCESS EXPORT LISTS
- exportsFromAvail this_mod exports all_avails gbl_env `thenRn` \ exported_avails ->
-
- -- DONE
- returnRn (gbl_env, exported_avails, Just all_avails)
- ) `thenRn` \ (gbl_env, exported_avails, maybe_stuff) ->
-
- case maybe_stuff of {
- Nothing -> returnRn Nothing ;
- Just all_avails ->
-
- traceRn (text "updateProv" <+> fsep (map ppr (rdrEnvElts gbl_env))) `thenRn_`
-
- -- DEAL WITH FIXITIES
- fixitiesFromLocalDecls gbl_env decls `thenRn` \ local_fixity_env ->
- let
- -- Export only those fixities that are for names that are
- -- (a) defined in this module
- -- (b) exported
- exported_fixities :: [(Name,Fixity)]
- exported_fixities = [(name,fixity) | FixitySig name fixity _ <- nameEnvElts local_fixity_env,
- isLocallyDefined name
- ]
- in
- traceRn (text "fixity env" <+> vcat (map ppr (nameEnvElts local_fixity_env))) `thenRn_`
-
- --- TIDY UP
- let
- export_env = ExportEnv exported_avails exported_fixities
- (_, global_avail_env) = all_avails
- in
- returnRn (Just (export_env, gbl_env, local_fixity_env, global_avail_env))
- }
- where
- junk_exp_fn = error "RnNames:export_fn"
-
- all_imports = prel_imports ++ imports
-
- -- 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_Name ||
- explicit_prelude_import ||
- opt_NoImplicitPrelude
- = []
-
- | otherwise = [ImportDecl pRELUDE_Name
- ImportByUser
- False {- Not qualified -}
- Nothing {- No "as" -}
- Nothing {- No import list -}
- mod_loc]
-
- explicit_prelude_import
- = 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
-
- 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
- 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 :: (Name -> Bool) -- OK to omit qualifier
- -> RdrNameImportDecl
- -> RnMG (GlobalRdrEnv,
- ExportAvails)
-
-importsFromImportDecl is_unqual (ImportDecl imp_mod_name from qual_only as_mod import_spec iloc)
- = pushSrcLocRn iloc $
- getInterfaceExports imp_mod_name from `thenRn` \ (imp_mod, avails) ->
-
- if null avails then
- -- If there's an error in getInterfaceExports, (e.g. interface
- -- file not found) we get lots of spurious errors from 'filterImports'
- returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name)
- else
-
- filterImports imp_mod_name import_spec avails `thenRn` \ (filtered_avails, hides, explicits) ->
-
- -- We 'improve' the provenance by setting
- -- (a) the import-reason field, so that the Name says how it came into scope
- -- including whether it's explicitly imported
- -- (b) the print-unqualified field
- -- But don't fiddle with wired-in things or we get in a twist
- let
- improve_prov name = setNameProvenance name (NonLocalDef (UserImport imp_mod iloc (is_explicit name))
- (is_unqual name))
- is_explicit name = name `elemNameSet` explicits
- in
- qualifyImports imp_mod_name
- (not qual_only) -- Maybe want unqualified names
- as_mod hides
- filtered_avails improve_prov `thenRn` \ (rdr_name_env, mod_avails) ->
-
- returnRn (rdr_name_env, mod_avails)
-\end{code}
-
-
-\begin{code}
-importsFromLocalDecls mod_name rec_exp_fn decls
- = mapRn (getLocalDeclBinders newLocalName) decls `thenRn` \ avails_s ->
-
- 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 = filter non_singleton (equivClassesByUniq getUnique all_names)
- where
- non_singleton (x1:x2:xs) = True
- non_singleton other = False
- in
- -- Check for duplicate definitions
- mapRn_ (addErrRn . dupDeclErr) dups `thenRn_`
-
- -- Record that locally-defined things are available
- mapRn_ (recordSlurp Nothing) avails `thenRn_`
-
- -- Build the environment
- qualifyImports mod_name
- True -- Want unqualified names
- Nothing -- no 'as M'
- [] -- Hide nothing
- avails
- (\n -> n)
-
- where
- newLocalName rdr_name loc = newLocalTopBinder mod (rdrNameOcc rdr_name)
- rec_exp_fn loc
- mod = mkThisModule mod_name
-
-getLocalDeclBinders :: (RdrName -> SrcLoc -> RnMG Name) -- New-name function
- -> RdrNameHsDecl
- -> RnMG Avails
-getLocalDeclBinders new_name (ValD binds)
- = mapRn do_one (bagToList (collectTopBinders binds))
- where
- do_one (rdr_name, loc) = new_name rdr_name loc `thenRn` \ name ->
- returnRn (Avail name)
-
- -- foreign declarations
-getLocalDeclBinders new_name (ForD (ForeignDecl nm kind _ dyn _ loc))
- | binds_haskell_name kind dyn
- = new_name nm loc `thenRn` \ name ->
- returnRn [Avail name]
-
- | otherwise
- = returnRn []
-
-getLocalDeclBinders new_name decl
- = getDeclBinders new_name decl `thenRn` \ maybe_avail ->
- case maybe_avail of
- Nothing -> returnRn [] -- Instance decls and suchlike
- Just avail -> returnRn [avail]
-
-binds_haskell_name (FoImport _) _ = True
-binds_haskell_name FoLabel _ = True
-binds_haskell_name FoExport ext_nm = isDynamic ext_nm
-
-fixitiesFromLocalDecls :: GlobalRdrEnv -> [RdrNameHsDecl] -> RnMG FixityEnv
-fixitiesFromLocalDecls gbl_env decls
- = foldlRn getFixities emptyNameEnv decls
- where
- getFixities :: FixityEnv -> RdrNameHsDecl -> RnMG FixityEnv
- getFixities acc (FixD fix)
- = fix_decl acc fix
-
- getFixities acc (TyClD (ClassDecl _ _ _ sigs _ _ _ _ _ _))
- = foldlRn fix_decl acc [sig | FixSig sig <- sigs]
- -- Get fixities from class decl sigs too.
- getFixities acc other_decl
- = returnRn acc
-
- fix_decl acc sig@(FixitySig rdr_name fixity loc)
- = -- Check for fixity decl for something not declared
- case lookupRdrEnv gbl_env rdr_name of {
- Nothing | opt_WarnUnusedBinds
- -> pushSrcLocRn loc (addWarnRn (unusedFixityDecl rdr_name fixity)) `thenRn_`
- returnRn acc
- | otherwise -> returnRn acc ;
-
- Just (name:_) ->
-
- -- Check for duplicate fixity decl
- case lookupNameEnv acc name of {
- Just (FixitySig _ _ loc') -> addErrRn (dupFixityDecl rdr_name loc loc') `thenRn_`
- returnRn acc ;
-
- Nothing -> returnRn (addToNameEnv acc name (FixitySig name fixity loc))
- }}
-\end{code}
-
-%************************************************************************
-%* *
-\subsection{Filtering imports}
-%* *
-%************************************************************************
-
-@filterImports@ takes the @ExportEnv@ telling what the imported module makes
-available, and filters it through the import spec (if any).
-
-\begin{code}
-filterImports :: ModuleName -- The module being imported
- -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding
- -> [AvailInfo] -- What's available
- -> RnMG ([AvailInfo], -- What's actually imported
- [AvailInfo], -- What's to be hidden (the unqualified version, that is)
- 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, [], emptyNameSet)
-
-filterImports mod (Just (want_hiding, import_items)) avails
- = mapMaybeRn check_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
- -- All imported; item_avails to be hidden
- returnRn (avails, item_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 <- 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.
-
- check_item item@(IEModuleContents _)
- = addErrRn (badImportItemErr mod item) `thenRn_`
- returnRn Nothing
-
- check_item item
- | not (maybeToBool maybe_in_import_avails) ||
- not (maybeToBool maybe_filtered_avail)
- = addErrRn (badImportItemErr mod item) `thenRn_`
- returnRn Nothing
-
- | dodgy_import = addWarnRn (dodgyImportWarn mod item) `thenRn_`
- returnRn (Just (filtered_avail, explicits))
-
- | otherwise = returnRn (Just (filtered_avail, explicits))
-
- where
- wanted_occ = rdrNameOcc (ieName item)
- maybe_in_import_avails = lookupFM import_fm wanted_occ
-
- Just avail = maybe_in_import_avails
- maybe_filtered_avail = filterAvail item avail
- Just filtered_avail = maybe_filtered_avail
- explicits | dot_dot = [availName filtered_avail]
- | otherwise = availNames filtered_avail
-
- dot_dot = case item of
- IEThingAll _ -> True
- other -> False
-
- dodgy_import = case (item, avail) of
- (IEThingAll _, AvailTC _ [n]) -> True
- -- This occurs when you import T(..), but
- -- only export T abstractly. The single [n]
- -- in the AvailTC is the type or class itself
-
- other -> False
-\end{code}
-
-
-
-%************************************************************************
-%* *
-\subsection{Qualifiying imports}
-%* *
-%************************************************************************
-
-@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 :: ModuleName -- Imported module
- -> Bool -- True <=> want unqualified import
- -> Maybe ModuleName -- Optional "as M" part
- -> [AvailInfo] -- What's to be hidden
- -> Avails -- Whats imported and how
- -> (Name -> Name) -- Improves the provenance on imported things
- -> RnMG (GlobalRdrEnv, ExportAvails)
- -- NB: the Names in ExportAvails don't have the improve-provenance
- -- function applied to them
- -- We could fix that, but I don't think it matters
-
-qualifyImports this_mod unqual_imp as_mod hides
- avails improve_prov
- =
- -- Make the name environment. We're talking about a
- -- single module here, so there must be no name clashes.
- -- In practice there only ever will be if it's the module
- -- being compiled.
- let
- -- Add the things that are available
- name_env1 = foldl add_avail emptyRdrEnv avails
-
- -- Delete things that are hidden
- name_env2 = foldl del_avail name_env1 hides
-
- -- Create the export-availability info
- export_avails = mkExportAvails qual_mod unqual_imp name_env2 avails
- in
- returnRn (name_env2, export_avails)
-
- where
- qual_mod = case as_mod of
- Nothing -> this_mod
- Just another_name -> another_name
-
- add_avail :: GlobalRdrEnv -> AvailInfo -> GlobalRdrEnv
- add_avail env avail = foldl add_name env (availNames avail)
-
- add_name env name
- | unqual_imp = env2
- | otherwise = env1
- where
- env1 = addOneToGlobalRdrEnv env (mkRdrQual qual_mod occ) better_name
- env2 = addOneToGlobalRdrEnv env1 (mkRdrUnqual occ) better_name
- occ = nameOccName name
- better_name = improve_prov name
-
- del_avail env avail = foldl delOneFromGlobalRdrEnv env rdr_names
- where
- rdr_names = map (mkRdrUnqual . nameOccName) (availNames avail)
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{Export list processing
-%* *
-%************************************************************************
-
-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...
-
-\begin{code}
-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
- NameEnv AvailInfo) -- 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
- -> ExportAvails
- -> 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 global_name_env
- = exportsFromAvail this_mod true_exports export_avails global_name_env
- where
- true_exports = Just $ if this_mod == mAIN_Name
- then [IEVar main_RDR]
- -- 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)
- global_name_env
- = foldlRn exports_from_item
- ([], emptyFM, emptyNameEnv) export_items `thenRn` \ (_, _, export_avail_map) ->
- let
- export_avails :: [AvailInfo]
- export_avails = nameEnvElts export_avail_map
- in
- returnRn export_avails
-
- where
- exports_from_item :: ExportAccum -> RdrNameIE -> RnMG ExportAccum
-
- exports_from_item acc@(mods, occs, avails) ie@(IEModuleContents mod)
- | mod `elem` mods -- Duplicate export of M
- = warnCheckRn opt_WarnDuplicateExports
- (dupModuleExport mod) `thenRn_`
- returnRn acc
-
- | otherwise
- = case lookupFM mod_avail_env mod of
- Nothing -> failWithRn acc (modExportErr mod)
- Just mod_avails -> foldlRn (check_occs ie) occs mod_avails `thenRn` \ occs' ->
- let
- avails' = foldl add_avail avails mod_avails
- in
- returnRn (mod:mods, occs', avails')
-
- exports_from_item acc@(mods, occs, avails) ie
- | not (maybeToBool maybe_in_scope)
- = failWithRn acc (unknownNameErr (ieName ie))
-
- | not (null dup_names)
- = addNameClashErrRn rdr_name (name:dup_names) `thenRn_`
- returnRn acc
-
-#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 acc
-#endif
-
- | not enough_avail
- = failWithRn acc (exportItemErr ie)
-
- | otherwise -- Phew! It's OK! Now to check the occurrence stuff!
- = check_occs ie occs export_avail `thenRn` \ occs' ->
- returnRn (mods, occs', add_avail avails export_avail)
-
- where
- rdr_name = ieName ie
- maybe_in_scope = lookupFM global_name_env rdr_name
- Just (name:dup_names) = maybe_in_scope
- maybe_avail = lookupUFM entity_avail_env name
- Just avail = maybe_avail
- maybe_export_avail = filterAvail ie avail
- enough_avail = maybeToBool maybe_export_avail
- Just export_avail = maybe_export_avail
-
-add_avail avails avail = addToNameEnv_C plusAvail avails (availName avail) avail
-
-check_occs :: RdrNameIE -> ExportOccMap -> AvailInfo -> RnMG ExportOccMap
-check_occs ie occs avail
- = foldlRn check occs (availNames avail)
- where
- check occs name
- = case lookupFM occs name_occ of
- Nothing -> returnRn (addToFM occs name_occ (name, ie))
- Just (name', ie')
- | name == name' -> -- Duplicate export
- warnCheckRn opt_WarnDuplicateExports
- (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
-
-mk_export_fn :: NameSet -> (Name -> ExportFlag)
-mk_export_fn exported_names
- = \name -> if name `elemNameSet` exported_names
- then Exported
- else NotExported
-\end{code}
-
-%************************************************************************
-%* *
-\subsection{Errors}
-%* *
-%************************************************************************
-
-\begin{code}
-badImportItemErr mod ie
- = sep [ptext SLIT("Module"), quotes (pprModuleName mod),
- ptext SLIT("does not export"), quotes (ppr ie)]
-
-dodgyImportWarn mod (IEThingAll tc)
- = sep [ptext SLIT("Module") <+> quotes (pprModuleName mod) <+> ptext SLIT("exports") <+> quotes (ppr tc),
- ptext SLIT("with no constructors/class operations;"),
- ptext SLIT("yet it is imported with a (..)")]
-
-modExportErr mod
- = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (pprModuleName mod)]
-
-exportItemErr export_item
- = sep [ ptext SLIT("Bad export item"), quotes (ppr export_item)]
-
-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)]
-
-dupDeclErr (n:ns)
- = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),
- nest 4 (vcat (map pp sorted_ns))]
- where
- sorted_ns = sortLt occ'ed_before (n:ns)
-
- occ'ed_before a b = LT == compare (getSrcLoc a) (getSrcLoc b)
-
- pp n = pprProvenance (getNameProvenance n)
-
-dupExportWarn occ_name ie1 ie2
- = hsep [quotes (ppr occ_name),
- ptext SLIT("is exported by"), quotes (ppr ie1),
- ptext SLIT("and"), quotes (ppr ie2)]
-
-dupModuleExport mod
- = hsep [ptext SLIT("Duplicate"),
- quotes (ptext SLIT("Module") <+> pprModuleName mod),
- ptext SLIT("in export list")]
-
-unusedFixityDecl rdr_name fixity
- = hsep [ptext SLIT("Unused fixity declaration for"), quotes (ppr rdr_name)]
-
-dupFixityDecl rdr_name loc1 loc2
- = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name),
- ptext SLIT("at ") <+> ppr loc1,
- ptext SLIT("and") <+> ppr loc2]
-
-\end{code}
+%\r
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998\r
+%\r
+\section[RnNames]{Extracting imported and top-level names in scope}\r
+\r
+\begin{code}\r
+module RnNames (\r
+ getGlobalNames\r
+ ) where\r
+\r
+#include "HsVersions.h"\r
+\r
+import CmdLineOpts ( opt_NoImplicitPrelude, opt_WarnDuplicateExports, \r
+ opt_SourceUnchanged, opt_WarnUnusedBinds\r
+ )\r
+\r
+import HsSyn ( HsModule(..), HsDecl(..), TyClDecl(..),\r
+ IE(..), ieName, \r
+ ForeignDecl(..), ForKind(..), isDynamic,\r
+ FixitySig(..), Sig(..), ImportDecl(..),\r
+ collectTopBinders\r
+ )\r
+import RdrHsSyn ( RdrNameIE, RdrNameImportDecl,\r
+ RdrNameHsModule, RdrNameHsDecl\r
+ )\r
+import RnIfaces ( getInterfaceExports, getDeclBinders,\r
+ recordSlurp, checkUpToDate\r
+ )\r
+import RnEnv\r
+import RnMonad\r
+\r
+import FiniteMap\r
+import PrelMods\r
+import PrelInfo ( main_RDR )\r
+import UniqFM ( lookupUFM )\r
+import Bag ( bagToList )\r
+import Maybes ( maybeToBool )\r
+import Module ( ModuleName, mkThisModule, pprModuleName, WhereFrom(..) )\r
+import NameSet\r
+import Name ( Name, ExportFlag(..), ImportReason(..), Provenance(..),\r
+ isLocallyDefined, setNameProvenance,\r
+ nameOccName, getSrcLoc, pprProvenance, getNameProvenance\r
+ )\r
+import RdrName ( RdrName, rdrNameOcc, mkRdrQual, mkRdrUnqual, isQual )\r
+import SrcLoc ( SrcLoc )\r
+import NameSet ( elemNameSet, emptyNameSet )\r
+import Outputable\r
+import Unique ( getUnique )\r
+import Util ( removeDups, equivClassesByUniq, sortLt )\r
+import List ( partition )\r
+\end{code}\r
+\r
+\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Get global names}\r
+%* *\r
+%************************************************************************\r
+\r
+\begin{code}\r
+getGlobalNames :: RdrNameHsModule\r
+ -> RnMG (Maybe (ExportEnv, \r
+ GlobalRdrEnv,\r
+ FixityEnv, -- Fixities for local decls only\r
+ NameEnv AvailInfo -- Maps a name to its parent AvailInfo\r
+ -- Just for in-scope things only\r
+ ))\r
+ -- Nothing => no need to recompile\r
+\r
+getGlobalNames (HsModule this_mod _ exports imports decls mod_loc)\r
+ = -- These two fix-loops are to get the right\r
+ -- provenance information into a Name\r
+ fixRn (\ ~(rec_gbl_env, rec_exported_avails, _) ->\r
+\r
+ let\r
+ rec_unqual_fn :: Name -> Bool -- Is this chap in scope unqualified?\r
+ rec_unqual_fn = unQualInScope rec_gbl_env\r
+\r
+ rec_exp_fn :: Name -> ExportFlag\r
+ rec_exp_fn = mk_export_fn (availsToNameSet rec_exported_avails)\r
+ in\r
+ setModuleRn this_mod $\r
+\r
+ -- PROCESS LOCAL DECLS\r
+ -- Do these *first* so that the correct provenance gets\r
+ -- into the global name cache.\r
+ importsFromLocalDecls this_mod rec_exp_fn decls `thenRn` \ (local_gbl_env, local_mod_avails) ->\r
+\r
+ -- PROCESS IMPORT DECLS\r
+ -- Do the non {- SOURCE -} ones first, so that we get a helpful\r
+ -- warning for {- SOURCE -} ones that are unnecessary\r
+ let\r
+ (source, ordinary) = partition is_source_import all_imports\r
+ is_source_import (ImportDecl _ ImportByUserSource _ _ _ _) = True\r
+ is_source_import other = False\r
+ in\r
+ mapAndUnzipRn (importsFromImportDecl rec_unqual_fn) ordinary `thenRn` \ (imp_gbl_envs1, imp_avails_s1) ->\r
+ mapAndUnzipRn (importsFromImportDecl rec_unqual_fn) source `thenRn` \ (imp_gbl_envs2, imp_avails_s2) ->\r
+\r
+ -- COMBINE RESULTS\r
+ -- We put the local env second, so that a local provenance\r
+ -- "wins", even if a module imports itself.\r
+ let\r
+ gbl_env :: GlobalRdrEnv\r
+ imp_gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv (imp_gbl_envs2 ++ imp_gbl_envs1)\r
+ gbl_env = imp_gbl_env `plusGlobalRdrEnv` local_gbl_env\r
+\r
+ all_avails :: ExportAvails\r
+ all_avails = foldr plusExportAvails local_mod_avails (imp_avails_s2 ++ imp_avails_s1)\r
+ in\r
+\r
+ -- TRY FOR EARLY EXIT\r
+ -- We can't go for an early exit before this because we have to check\r
+ -- for name clashes. Consider:\r
+ --\r
+ -- module A where module B where\r
+ -- import B h = True\r
+ -- f = h\r
+ --\r
+ -- Suppose I've compiled everything up, and then I add a\r
+ -- new definition to module B, that defines "f".\r
+ --\r
+ -- Then I must detect the name clash in A before going for an early\r
+ -- exit. The early-exit code checks what's actually needed from B\r
+ -- to compile A, and of course that doesn't include B.f. That's\r
+ -- why we wait till after the plusEnv stuff to do the early-exit.\r
+ checkEarlyExit this_mod `thenRn` \ up_to_date ->\r
+ if up_to_date then\r
+ returnRn (gbl_env, junk_exp_fn, Nothing)\r
+ else\r
+ \r
+ -- RECORD BETTER PROVENANCES IN THE CACHE\r
+ -- The names in the envirnoment have better provenances (e.g. imported on line x)\r
+ -- than the names in the name cache. We update the latter now, so that we\r
+ -- we start renaming declarations we'll get the good names\r
+ -- The isQual is because the qualified name is always in scope\r
+ updateProvenances (concat [names | (rdr_name, names) <- rdrEnvToList imp_gbl_env, \r
+ isQual rdr_name]) `thenRn_`\r
+\r
+ -- PROCESS EXPORT LISTS\r
+ exportsFromAvail this_mod exports all_avails gbl_env `thenRn` \ exported_avails ->\r
+\r
+ -- DONE\r
+ returnRn (gbl_env, exported_avails, Just all_avails)\r
+ ) `thenRn` \ (gbl_env, exported_avails, maybe_stuff) ->\r
+\r
+ case maybe_stuff of {\r
+ Nothing -> returnRn Nothing ;\r
+ Just all_avails ->\r
+\r
+ traceRn (text "updateProv" <+> fsep (map ppr (rdrEnvElts gbl_env))) `thenRn_`\r
+ \r
+ -- DEAL WITH FIXITIES\r
+ fixitiesFromLocalDecls gbl_env decls `thenRn` \ local_fixity_env ->\r
+ let\r
+ -- Export only those fixities that are for names that are\r
+ -- (a) defined in this module\r
+ -- (b) exported\r
+ exported_fixities :: [(Name,Fixity)]\r
+ exported_fixities = [(name,fixity) | FixitySig name fixity _ <- nameEnvElts local_fixity_env,\r
+ isLocallyDefined name\r
+ ]\r
+ in\r
+ traceRn (text "fixity env" <+> vcat (map ppr (nameEnvElts local_fixity_env))) `thenRn_`\r
+\r
+ --- TIDY UP \r
+ let\r
+ export_env = ExportEnv exported_avails exported_fixities\r
+ (_, global_avail_env) = all_avails\r
+ in\r
+ returnRn (Just (export_env, gbl_env, local_fixity_env, global_avail_env))\r
+ }\r
+ where\r
+ junk_exp_fn = error "RnNames:export_fn"\r
+\r
+ all_imports = prel_imports ++ imports\r
+\r
+ -- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();\r
+ -- because the former doesn't even look at Prelude.hi for instance declarations,\r
+ -- whereas the latter does.\r
+ prel_imports | this_mod == pRELUDE_Name ||\r
+ explicit_prelude_import ||\r
+ opt_NoImplicitPrelude\r
+ = []\r
+\r
+ | otherwise = [ImportDecl pRELUDE_Name\r
+ ImportByUser\r
+ False {- Not qualified -}\r
+ Nothing {- No "as" -}\r
+ Nothing {- No import list -}\r
+ mod_loc]\r
+ \r
+ explicit_prelude_import\r
+ = not (null [ () | (ImportDecl mod _ _ _ _ _) <- imports, mod == pRELUDE_Name ])\r
+\end{code}\r
+ \r
+\begin{code}\r
+checkEarlyExit mod\r
+ = checkErrsRn `thenRn` \ no_errs_so_far ->\r
+ if not no_errs_so_far then\r
+ -- Found errors already, so exit now\r
+ returnRn True\r
+ else\r
+\r
+ traceRn (text "Considering whether compilation is required...") `thenRn_`\r
+ if not opt_SourceUnchanged then\r
+ -- Source code changed and no errors yet... carry on \r
+ traceRn (nest 4 (text "source file changed or recompilation check turned off")) `thenRn_` \r
+ returnRn False\r
+ else\r
+\r
+ -- Unchanged source, and no errors yet; see if usage info\r
+ -- up to date, and exit if so\r
+ checkUpToDate mod `thenRn` \ up_to_date ->\r
+ putDocRn (text "Compilation" <+> \r
+ text (if up_to_date then "IS NOT" else "IS") <+>\r
+ text "required") `thenRn_`\r
+ returnRn up_to_date\r
+\end{code}\r
+ \r
+\begin{code}\r
+importsFromImportDecl :: (Name -> Bool) -- OK to omit qualifier\r
+ -> RdrNameImportDecl\r
+ -> RnMG (GlobalRdrEnv, \r
+ ExportAvails) \r
+\r
+importsFromImportDecl is_unqual (ImportDecl imp_mod_name from qual_only as_mod import_spec iloc)\r
+ = pushSrcLocRn iloc $\r
+ getInterfaceExports imp_mod_name from `thenRn` \ (imp_mod, avails) ->\r
+\r
+ if null avails then\r
+ -- If there's an error in getInterfaceExports, (e.g. interface\r
+ -- file not found) we get lots of spurious errors from 'filterImports'\r
+ returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name)\r
+ else\r
+\r
+ filterImports imp_mod_name import_spec avails `thenRn` \ (filtered_avails, hides, explicits) ->\r
+\r
+ -- We 'improve' the provenance by setting\r
+ -- (a) the import-reason field, so that the Name says how it came into scope\r
+ -- including whether it's explicitly imported\r
+ -- (b) the print-unqualified field\r
+ -- But don't fiddle with wired-in things or we get in a twist\r
+ let\r
+ improve_prov name = setNameProvenance name (NonLocalDef (UserImport imp_mod iloc (is_explicit name)) \r
+ (is_unqual name))\r
+ is_explicit name = name `elemNameSet` explicits\r
+ in\r
+ qualifyImports imp_mod_name\r
+ (not qual_only) -- Maybe want unqualified names\r
+ as_mod hides\r
+ filtered_avails improve_prov `thenRn` \ (rdr_name_env, mod_avails) ->\r
+\r
+ returnRn (rdr_name_env, mod_avails)\r
+\end{code}\r
+\r
+\r
+\begin{code}\r
+importsFromLocalDecls mod_name rec_exp_fn decls\r
+ = mapRn (getLocalDeclBinders newLocalName) decls `thenRn` \ avails_s ->\r
+\r
+ let\r
+ avails = concat avails_s\r
+\r
+ all_names :: [Name] -- All the defns; no dups eliminated\r
+ all_names = [name | avail <- avails, name <- availNames avail]\r
+\r
+ dups :: [[Name]]\r
+ dups = filter non_singleton (equivClassesByUniq getUnique all_names)\r
+ where\r
+ non_singleton (x1:x2:xs) = True\r
+ non_singleton other = False\r
+ in\r
+ -- Check for duplicate definitions\r
+ mapRn_ (addErrRn . dupDeclErr) dups `thenRn_` \r
+\r
+ -- Record that locally-defined things are available\r
+ mapRn_ (recordSlurp Nothing) avails `thenRn_`\r
+\r
+ -- Build the environment\r
+ qualifyImports mod_name \r
+ True -- Want unqualified names\r
+ Nothing -- no 'as M'\r
+ [] -- Hide nothing\r
+ avails\r
+ (\n -> n)\r
+\r
+ where\r
+ newLocalName rdr_name loc = newLocalTopBinder mod (rdrNameOcc rdr_name)\r
+ rec_exp_fn loc\r
+ mod = mkThisModule mod_name\r
+\r
+getLocalDeclBinders :: (RdrName -> SrcLoc -> RnMG Name) -- New-name function\r
+ -> RdrNameHsDecl\r
+ -> RnMG Avails\r
+getLocalDeclBinders new_name (ValD binds)\r
+ = mapRn do_one (bagToList (collectTopBinders binds))\r
+ where\r
+ do_one (rdr_name, loc) = new_name rdr_name loc `thenRn` \ name ->\r
+ returnRn (Avail name)\r
+\r
+ -- foreign declarations\r
+getLocalDeclBinders new_name (ForD (ForeignDecl nm kind _ dyn _ loc))\r
+ | binds_haskell_name kind dyn\r
+ = new_name nm loc `thenRn` \ name ->\r
+ returnRn [Avail name]\r
+\r
+ | otherwise\r
+ = returnRn []\r
+\r
+getLocalDeclBinders new_name decl\r
+ = getDeclBinders new_name decl `thenRn` \ maybe_avail ->\r
+ case maybe_avail of\r
+ Nothing -> returnRn [] -- Instance decls and suchlike\r
+ Just avail -> returnRn [avail]\r
+\r
+binds_haskell_name (FoImport _) _ = True\r
+binds_haskell_name FoLabel _ = True\r
+binds_haskell_name FoExport ext_nm = isDynamic ext_nm\r
+\r
+fixitiesFromLocalDecls :: GlobalRdrEnv -> [RdrNameHsDecl] -> RnMG FixityEnv\r
+fixitiesFromLocalDecls gbl_env decls\r
+ = foldlRn getFixities emptyNameEnv decls\r
+ where\r
+ getFixities :: FixityEnv -> RdrNameHsDecl -> RnMG FixityEnv\r
+ getFixities acc (FixD fix)\r
+ = fix_decl acc fix\r
+\r
+ getFixities acc (TyClD (ClassDecl _ _ _ sigs _ _ _ _ _ _))\r
+ = foldlRn fix_decl acc [sig | FixSig sig <- sigs]\r
+ -- Get fixities from class decl sigs too.\r
+ getFixities acc other_decl\r
+ = returnRn acc\r
+\r
+ fix_decl acc sig@(FixitySig rdr_name fixity loc)\r
+ = -- Check for fixity decl for something not declared\r
+ case lookupRdrEnv gbl_env rdr_name of {\r
+ Nothing | opt_WarnUnusedBinds \r
+ -> pushSrcLocRn loc (addWarnRn (unusedFixityDecl rdr_name fixity)) `thenRn_`\r
+ returnRn acc \r
+ | otherwise -> returnRn acc ;\r
+ \r
+ Just (name:_) ->\r
+\r
+ -- Check for duplicate fixity decl\r
+ case lookupNameEnv acc name of {\r
+ Just (FixitySig _ _ loc') -> addErrRn (dupFixityDecl rdr_name loc loc') `thenRn_`\r
+ returnRn acc ;\r
+\r
+ Nothing -> returnRn (addToNameEnv acc name (FixitySig name fixity loc))\r
+ }}\r
+\end{code}\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Filtering imports}\r
+%* *\r
+%************************************************************************\r
+\r
+@filterImports@ takes the @ExportEnv@ telling what the imported module makes\r
+available, and filters it through the import spec (if any).\r
+\r
+\begin{code}\r
+filterImports :: ModuleName -- The module being imported\r
+ -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding\r
+ -> [AvailInfo] -- What's available\r
+ -> RnMG ([AvailInfo], -- What's actually imported\r
+ [AvailInfo], -- What's to be hidden (the unqualified version, that is)\r
+ NameSet) -- What was imported explicitly\r
+\r
+ -- Complains if import spec mentions things that the module doesn't export\r
+ -- Warns/informs if import spec contains duplicates.\r
+filterImports mod Nothing imports\r
+ = returnRn (imports, [], emptyNameSet)\r
+\r
+filterImports mod (Just (want_hiding, import_items)) avails\r
+ = mapMaybeRn check_item import_items `thenRn` \ avails_w_explicits ->\r
+ let\r
+ (item_avails, explicits_s) = unzip avails_w_explicits\r
+ explicits = foldl addListToNameSet emptyNameSet explicits_s\r
+ in\r
+ if want_hiding \r
+ then \r
+ -- All imported; item_avails to be hidden\r
+ returnRn (avails, item_avails, emptyNameSet)\r
+ else\r
+ -- Just item_avails imported; nothing to be hidden\r
+ returnRn (item_avails, [], explicits)\r
+ where\r
+ import_fm :: FiniteMap OccName AvailInfo\r
+ import_fm = listToFM [ (nameOccName name, avail) \r
+ | avail <- avails,\r
+ name <- availNames avail]\r
+ -- Even though availNames returns data constructors too,\r
+ -- they won't make any difference because naked entities like T\r
+ -- in an import list map to TcOccs, not VarOccs.\r
+\r
+ check_item item@(IEModuleContents _)\r
+ = addErrRn (badImportItemErr mod item) `thenRn_`\r
+ returnRn Nothing\r
+\r
+ check_item item\r
+ | not (maybeToBool maybe_in_import_avails) ||\r
+ not (maybeToBool maybe_filtered_avail)\r
+ = addErrRn (badImportItemErr mod item) `thenRn_`\r
+ returnRn Nothing\r
+\r
+ | dodgy_import = addWarnRn (dodgyImportWarn mod item) `thenRn_`\r
+ returnRn (Just (filtered_avail, explicits))\r
+\r
+ | otherwise = returnRn (Just (filtered_avail, explicits))\r
+ \r
+ where\r
+ wanted_occ = rdrNameOcc (ieName item)\r
+ maybe_in_import_avails = lookupFM import_fm wanted_occ\r
+\r
+ Just avail = maybe_in_import_avails\r
+ maybe_filtered_avail = filterAvail item avail\r
+ Just filtered_avail = maybe_filtered_avail\r
+ explicits | dot_dot = [availName filtered_avail]\r
+ | otherwise = availNames filtered_avail\r
+\r
+ dot_dot = case item of \r
+ IEThingAll _ -> True\r
+ other -> False\r
+\r
+ dodgy_import = case (item, avail) of\r
+ (IEThingAll _, AvailTC _ [n]) -> True\r
+ -- This occurs when you import T(..), but\r
+ -- only export T abstractly. The single [n]\r
+ -- in the AvailTC is the type or class itself\r
+ \r
+ other -> False\r
+\end{code}\r
+\r
+\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Qualifiying imports}\r
+%* *\r
+%************************************************************************\r
+\r
+@qualifyImports@ takes the @ExportEnv@ after filtering through the import spec\r
+of an import decl, and deals with producing an @RnEnv@ with the \r
+right qualified names. It also turns the @Names@ in the @ExportEnv@ into\r
+fully fledged @Names@.\r
+\r
+\begin{code}\r
+qualifyImports :: ModuleName -- Imported module\r
+ -> Bool -- True <=> want unqualified import\r
+ -> Maybe ModuleName -- Optional "as M" part \r
+ -> [AvailInfo] -- What's to be hidden\r
+ -> Avails -- Whats imported and how\r
+ -> (Name -> Name) -- Improves the provenance on imported things\r
+ -> RnMG (GlobalRdrEnv, ExportAvails)\r
+ -- NB: the Names in ExportAvails don't have the improve-provenance\r
+ -- function applied to them\r
+ -- We could fix that, but I don't think it matters\r
+\r
+qualifyImports this_mod unqual_imp as_mod hides\r
+ avails improve_prov\r
+ = \r
+ -- Make the name environment. We're talking about a \r
+ -- single module here, so there must be no name clashes.\r
+ -- In practice there only ever will be if it's the module\r
+ -- being compiled.\r
+ let\r
+ -- Add the things that are available\r
+ name_env1 = foldl add_avail emptyRdrEnv avails\r
+\r
+ -- Delete things that are hidden\r
+ name_env2 = foldl del_avail name_env1 hides\r
+\r
+ -- Create the export-availability info\r
+ export_avails = mkExportAvails qual_mod unqual_imp name_env2 avails\r
+ in\r
+ returnRn (name_env2, export_avails)\r
+\r
+ where\r
+ qual_mod = case as_mod of\r
+ Nothing -> this_mod\r
+ Just another_name -> another_name\r
+\r
+ add_avail :: GlobalRdrEnv -> AvailInfo -> GlobalRdrEnv\r
+ add_avail env avail = foldl add_name env (availNames avail)\r
+\r
+ add_name env name\r
+ | unqual_imp = env2\r
+ | otherwise = env1\r
+ where\r
+ env1 = addOneToGlobalRdrEnv env (mkRdrQual qual_mod occ) better_name\r
+ env2 = addOneToGlobalRdrEnv env1 (mkRdrUnqual occ) better_name\r
+ occ = nameOccName name\r
+ better_name = improve_prov name\r
+\r
+ del_avail env avail = foldl delOneFromGlobalRdrEnv env rdr_names\r
+ where\r
+ rdr_names = map (mkRdrUnqual . nameOccName) (availNames avail)\r
+\end{code}\r
+\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Export list processing\r
+%* *\r
+%************************************************************************\r
+\r
+Processing the export list.\r
+\r
+You might think that we should record things that appear in the export list as\r
+``occurrences'' (using addOccurrenceName), but you'd be wrong. We do check (here)\r
+that they are in scope, but there is no need to slurp in their actual declaration\r
+(which is what addOccurrenceName forces). Indeed, doing so would big trouble when\r
+compiling PrelBase, because it re-exports GHC, which includes takeMVar#, whose type\r
+includes ConcBase.StateAndSynchVar#, and so on...\r
+\r
+\begin{code}\r
+type ExportAccum -- The type of the accumulating parameter of\r
+ -- the main worker function in exportsFromAvail\r
+ = ([ModuleName], -- 'module M's seen so far\r
+ ExportOccMap, -- Tracks exported occurrence names\r
+ NameEnv AvailInfo) -- The accumulated exported stuff, kept in an env\r
+ -- so we can common-up related AvailInfos\r
+\r
+type ExportOccMap = FiniteMap OccName (Name, RdrNameIE)\r
+ -- Tracks what a particular exported OccName\r
+ -- in an export list refers to, and which item\r
+ -- it came from. It's illegal to export two distinct things\r
+ -- that have the same occurrence name\r
+\r
+\r
+exportsFromAvail :: ModuleName\r
+ -> Maybe [RdrNameIE] -- Export spec\r
+ -> ExportAvails\r
+ -> GlobalRdrEnv \r
+ -> RnMG Avails\r
+ -- Complains if two distinct exports have same OccName\r
+ -- Warns about identical exports.\r
+ -- Complains about exports items not in scope\r
+exportsFromAvail this_mod Nothing export_avails global_name_env\r
+ = exportsFromAvail this_mod true_exports export_avails global_name_env\r
+ where\r
+ true_exports = Just $ if this_mod == mAIN_Name\r
+ then [IEVar main_RDR]\r
+ -- export Main.main *only* unless otherwise specified,\r
+ else [IEModuleContents this_mod]\r
+ -- but for all other modules export everything.\r
+\r
+exportsFromAvail this_mod (Just export_items) \r
+ (mod_avail_env, entity_avail_env)\r
+ global_name_env\r
+ = foldlRn exports_from_item\r
+ ([], emptyFM, emptyNameEnv) export_items `thenRn` \ (_, _, export_avail_map) ->\r
+ let\r
+ export_avails :: [AvailInfo]\r
+ export_avails = nameEnvElts export_avail_map\r
+ in\r
+ returnRn export_avails\r
+\r
+ where\r
+ exports_from_item :: ExportAccum -> RdrNameIE -> RnMG ExportAccum\r
+\r
+ exports_from_item acc@(mods, occs, avails) ie@(IEModuleContents mod)\r
+ | mod `elem` mods -- Duplicate export of M\r
+ = warnCheckRn opt_WarnDuplicateExports\r
+ (dupModuleExport mod) `thenRn_`\r
+ returnRn acc\r
+\r
+ | otherwise\r
+ = case lookupFM mod_avail_env mod of\r
+ Nothing -> failWithRn acc (modExportErr mod)\r
+ Just mod_avails -> foldlRn (check_occs ie) occs mod_avails `thenRn` \ occs' ->\r
+ let\r
+ avails' = foldl add_avail avails mod_avails\r
+ in\r
+ returnRn (mod:mods, occs', avails')\r
+\r
+ exports_from_item acc@(mods, occs, avails) ie\r
+ | not (maybeToBool maybe_in_scope) \r
+ = failWithRn acc (unknownNameErr (ieName ie))\r
+\r
+ | not (null dup_names)\r
+ = addNameClashErrRn rdr_name (name:dup_names) `thenRn_`\r
+ returnRn acc\r
+\r
+#ifdef DEBUG\r
+ -- I can't see why this should ever happen; if the thing is in scope\r
+ -- at all it ought to have some availability\r
+ | not (maybeToBool maybe_avail)\r
+ = pprTrace "exportsFromAvail: curious Nothing:" (ppr name)\r
+ returnRn acc\r
+#endif\r
+\r
+ | not enough_avail\r
+ = failWithRn acc (exportItemErr ie)\r
+\r
+ | otherwise -- Phew! It's OK! Now to check the occurrence stuff!\r
+ = check_occs ie occs export_avail `thenRn` \ occs' ->\r
+ returnRn (mods, occs', add_avail avails export_avail)\r
+\r
+ where\r
+ rdr_name = ieName ie\r
+ maybe_in_scope = lookupFM global_name_env rdr_name\r
+ Just (name:dup_names) = maybe_in_scope\r
+ maybe_avail = lookupUFM entity_avail_env name\r
+ Just avail = maybe_avail\r
+ maybe_export_avail = filterAvail ie avail\r
+ enough_avail = maybeToBool maybe_export_avail\r
+ Just export_avail = maybe_export_avail\r
+\r
+add_avail avails avail = addToNameEnv_C plusAvail avails (availName avail) avail\r
+\r
+check_occs :: RdrNameIE -> ExportOccMap -> AvailInfo -> RnMG ExportOccMap\r
+check_occs ie occs avail \r
+ = foldlRn check occs (availNames avail)\r
+ where\r
+ check occs name\r
+ = case lookupFM occs name_occ of\r
+ Nothing -> returnRn (addToFM occs name_occ (name, ie))\r
+ Just (name', ie') \r
+ | name == name' -> -- Duplicate export\r
+ warnCheckRn opt_WarnDuplicateExports\r
+ (dupExportWarn name_occ ie ie') `thenRn_`\r
+ returnRn occs\r
+\r
+ | otherwise -> -- Same occ name but different names: an error\r
+ failWithRn occs (exportClashErr name_occ ie ie')\r
+ where\r
+ name_occ = nameOccName name\r
+ \r
+mk_export_fn :: NameSet -> (Name -> ExportFlag)\r
+mk_export_fn exported_names\r
+ = \name -> if name `elemNameSet` exported_names\r
+ then Exported\r
+ else NotExported\r
+\end{code}\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Errors}\r
+%* *\r
+%************************************************************************\r
+\r
+\begin{code}\r
+badImportItemErr mod ie\r
+ = sep [ptext SLIT("Module"), quotes (pprModuleName mod), \r
+ ptext SLIT("does not export"), quotes (ppr ie)]\r
+\r
+dodgyImportWarn mod (IEThingAll tc)\r
+ = sep [ptext SLIT("Module") <+> quotes (pprModuleName mod) <+> ptext SLIT("exports") <+> quotes (ppr tc), \r
+ ptext SLIT("with no constructors/class operations;"),\r
+ ptext SLIT("yet it is imported with a (..)")]\r
+\r
+modExportErr mod\r
+ = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (pprModuleName mod)]\r
+\r
+exportItemErr export_item\r
+ = sep [ ptext SLIT("Bad export item"), quotes (ppr export_item)]\r
+\r
+exportClashErr occ_name ie1 ie2\r
+ = hsep [ptext SLIT("The export items"), quotes (ppr ie1), ptext SLIT("and"), quotes (ppr ie2),\r
+ ptext SLIT("create conflicting exports for"), quotes (ppr occ_name)]\r
+\r
+dupDeclErr (n:ns)\r
+ = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),\r
+ nest 4 (vcat (map pp sorted_ns))]\r
+ where\r
+ sorted_ns = sortLt occ'ed_before (n:ns)\r
+\r
+ occ'ed_before a b = LT == compare (getSrcLoc a) (getSrcLoc b)\r
+\r
+ pp n = pprProvenance (getNameProvenance n)\r
+\r
+dupExportWarn occ_name ie1 ie2\r
+ = hsep [quotes (ppr occ_name), \r
+ ptext SLIT("is exported by"), quotes (ppr ie1),\r
+ ptext SLIT("and"), quotes (ppr ie2)]\r
+\r
+dupModuleExport mod\r
+ = hsep [ptext SLIT("Duplicate"),\r
+ quotes (ptext SLIT("Module") <+> pprModuleName mod), \r
+ ptext SLIT("in export list")]\r
+\r
+unusedFixityDecl rdr_name fixity\r
+ = hsep [ptext SLIT("Unused fixity declaration for"), quotes (ppr rdr_name)]\r
+\r
+dupFixityDecl rdr_name loc1 loc2\r
+ = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name),\r
+ ptext SLIT("at ") <+> ppr loc1,\r
+ ptext SLIT("and") <+> ppr loc2]\r
+\r
+\end{code}\r
projects / ghc-hetmet.git / blobdiff