X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnNames.lhs;h=7c65a96e25b56f97c96cda32b436b64398f778c0;hb=6d1815b09469c68c9d15b253745876403c7fb084;hp=b7335939ff7e97f9d89c84ca2d91f6024693724c;hpb=301b341806ff4c6ad8e0c947530e0fbe9094caa7;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnNames.lhs b/ghc/compiler/rename/RnNames.lhs index b733593..7c65a96 100644 --- a/ghc/compiler/rename/RnNames.lhs +++ b/ghc/compiler/rename/RnNames.lhs @@ -5,44 +5,43 @@ \begin{code} module RnNames ( - getGlobalNames + getGlobalNames, exportsFromAvail ) where #include "HsVersions.h" -import CmdLineOpts ( opt_NoImplicitPrelude, opt_WarnDuplicateExports, - opt_SourceUnchanged - ) - -import HsSyn ( HsModule(..), ImportDecl(..), HsDecl(..), TyClDecl(..), - IE(..), ieName, - ForeignDecl(..), ForKind(..), isDynamic, - FixitySig(..), Sig(..), - collectTopBinders - ) -import RdrHsSyn ( RdrName(..), RdrNameIE, RdrNameImportDecl, - RdrNameHsModule, RdrNameHsDecl, - rdrNameOcc, ieOcc - ) -import RnIfaces ( getInterfaceExports, getDeclBinders, getImportedFixities, - recordSlurp, checkUpToDate, loadHomeInterface - ) -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 ( lookupUFM ) -import Bag ( bagToList ) -import Maybes ( maybeToBool ) -import Name -import SrcLoc ( SrcLoc ) -import NameSet ( elemNameSet, emptyNameSet ) +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(..) + ) +import RdrName ( rdrNameOcc, setRdrNameOcc ) +import OccName ( setOccNameSpace, dataName ) +import NameSet ( elemNameSet, emptyNameSet ) import Outputable -import Unique ( getUnique ) -import Util ( removeDups, equivClassesByUniq ) -import List ( nubBy ) +import Maybes ( maybeToBool, catMaybes, mapMaybe ) +import ListSetOps ( removeDups ) +import Util ( sortLt ) +import List ( partition ) \end{code} @@ -54,204 +53,141 @@ import List ( nubBy ) %************************************************************************ \begin{code} -getGlobalNames :: RdrNameHsModule - -> RnMG (Maybe (ExportEnv, - RnEnv, - 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_exp_fn, _) -> - - fixRn (\ ~(rec_rn_env, _) -> - let - rec_unqual_fn :: Name -> Bool -- Is this chap in scope unqualified? - rec_unqual_fn = mkPrintUnqualFn rec_rn_env - in - -- PROCESS LOCAL DECLS +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 rec_exp_fn decls `thenRn` \ (local_gbl_env, local_mod_avails) -> + importsFromLocalDecls this_mod decls `thenRn` \ (local_gbl_env, local_mod_avails) -> -- PROCESS IMPORT DECLS - mapAndUnzipRn (importsFromImportDecl this_mod rec_unqual_fn) - all_imports `thenRn` \ (imp_gbl_envs, imp_avails_s) -> + -- 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_envs + imp_gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv (imp_gbl_envs2 ++ imp_gbl_envs1) gbl_env = imp_gbl_env `plusGlobalRdrEnv` local_gbl_env - export_avails :: ExportAvails - export_avails = foldr plusExportAvails local_mod_avails imp_avails_s + all_avails :: ExportAvails + all_avails = foldr plusExportAvails local_mod_avails (imp_avails_s2 ++ imp_avails_s1) in - returnRn (gbl_env, export_avails) - ) `thenRn` \ (gbl_env, export_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 plusRnEnv stuff to do the early-exit. - checkEarlyExit this_mod `thenRn` \ up_to_date -> - if up_to_date then - returnRn (junk_exp_fn, Nothing) - else - - -- FIXITIES - fixitiesFromLocalDecls gbl_env decls `thenRn` \ local_fixity_env -> - getImportedFixities `thenRn` \ imp_fixity_env -> - let - fixity_env = imp_fixity_env `plusNameEnv` local_fixity_env - rn_env = RnEnv gbl_env fixity_env - (_, global_avail_env) = export_avails - in - traceRn (text "fixity env" <+> vcat (map ppr (nameEnvElts fixity_env))) `thenRn_` - - -- PROCESS EXPORT LISTS - exportsFromAvail this_mod exports export_avails rn_env `thenRn` \ (export_fn, export_env) -> - - -- DONE - returnRn (export_fn, Just (export_env, rn_env, global_avail_env)) - ) `thenRn` \ (_, result) -> - returnRn result + -- ALL DONE + returnRn (gbl_env, local_gbl_env, all_avails) where - junk_exp_fn = error "RnNames:export_fn" - - all_imports = prel_imports ++ imports + 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 - - 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 :: Module -- The module being compiled - -> (Name -> Bool) -- True => print unqualified +importsFromImportDecl :: ModuleName -> RdrNameImportDecl -> RnMG (GlobalRdrEnv, ExportAvails) -importsFromImportDecl this_mod rec_unqual_fn (ImportDecl imp_mod qual_only as_source as_mod import_spec iloc) +importsFromImportDecl this_mod_name (ImportDecl imp_mod_name from qual_only as_mod import_spec iloc) = pushSrcLocRn iloc $ - getInterfaceExports imp_mod as_source `thenRn` \ avails -> - if null avails then - -- If there's an error in getInterfaceExports, (e.g. interface + 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) + returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name) else - filterImports imp_mod import_spec avails `thenRn` \ (filtered_avails, hides, explicits) -> + -- Complain if we import a deprecated module + ifOptRn Opt_WarnDeprecations ( + case deprecs of + DeprecAll txt -> addWarnRn (moduleDeprec imp_mod_name txt) + other -> returnRn () + ) `thenRn_` - -- Load all the home modules for the things being - -- bought into scope. This makes sure their fixities - -- are loaded before we grab the FixityEnv from Ifaces - let - home_modules = [name | avail <- filtered_avails, - -- Doesn't take account of hiding, but that doesn't matter - - -- Drop NotAvailables. - -- Happens if filterAvail finds something missing - case avail of - NotAvailable -> False - other -> True, - - let name = availName avail, - not (isLocallyDefined name || nameModule name == imp_mod) - -- Don't try to load the module being compiled - -- (this can happen in mutual-recursion situations) - -- or from the module being imported (it's already loaded) - ] - - same_module n1 n2 = nameModule n1 == nameModule n2 - load n = loadHomeInterface (doc_str n) n - doc_str n = ptext SLIT("Need fixities from") <+> ppr (nameModule n) <+> parens (ppr n) - in - mapRn load (nubBy same_module home_modules) `thenRn_` - - -- 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 | isWiredInName name = name - | otherwise = setNameProvenance name (mk_new_prov name) + -- Filter the imports according to the import list + filterImports imp_mod_name from import_spec avails `thenRn` \ (filtered_avails, hides, explicits) -> - is_explicit name = name `elemNameSet` explicits - mk_new_prov name = NonLocalDef (UserImport imp_mod iloc (is_explicit name)) - as_source - (rec_unqual_fn name) + let + 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 hides deprecs + exports = mkExportAvails qual_mod unqual_imp gbl_env filtered_avails in - qualifyImports imp_mod - (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) + returnRn (gbl_env, exports) \end{code} \begin{code} -importsFromLocalDecls mod rec_exp_fn decls - = mapRn (getLocalDeclBinders newLocalName) decls `thenRn` \ avails_s -> - +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 @@ -259,90 +195,69 @@ importsFromLocalDecls mod rec_exp_fn decls 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 + (_, dups) = removeDups compare all_names in -- Check for duplicate definitions - mapRn (addErrRn . dupDeclErr) dups `thenRn_` - - -- Record that locally-defined things are available - mapRn (recordSlurp Nothing Compulsory) avails `thenRn_` + -- 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_` - -- Build the environment - qualifyImports mod - True -- Want unqualified names - Nothing -- no 'as M' - [] -- Hide nothing - avails - (\n -> n) + -- 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 + hides = [] -- Hide nothing + + gbl_env = mkGlobalRdrEnv mod_name unqual_imp mk_prov avails hides 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 :: (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) + new (rdr_name, loc) = newTopBinder mod 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 -> +getLocalDeclBinders mod (ForD (ForeignImport nm _ _ loc)) + = newTopBinder mod nm loc `thenRn` \ name -> returnRn [Avail name] - - | otherwise +getLocalDeclBinders mod (ForD _) = returnRn [] -getLocalDeclBinders new_name decl - = getDeclBinders new_name decl `thenRn` \ avail -> - case avail of - NotAvailable -> returnRn [] -- Instance decls and suchlike - other -> 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 (FixitySig rdr_name fixity loc) - = -- Check for fixity decl for something not declared - case lookupRdrEnv gbl_env rdr_name of { - Nothing -> pushSrcLocRn loc $ - addWarnRn (unusedFixityDecl rdr_name fixity) `thenRn_` - 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)) - }} +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} @@ -353,64 +268,90 @@ fixitiesFromLocalDecls gbl_env decls available, and filters it through the import spec (if any). \begin{code} -filterImports :: Module -- The module being imported +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 actually imported - [AvailInfo], -- What's to be hidden (the unqualified version, that is) + [AvailInfo], -- What's to be hidden + -- (It's convenient to return both the above sets, because + -- the substraction can be done more efficiently when + -- building the environment.) 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 +filterImports mod from Nothing imports = returnRn (imports, [], emptyNameSet) -filterImports mod (Just (want_hiding, import_items)) avails - = mapRn check_item import_items `thenRn` \ item_avails -> +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 -- All imported; item_avails to be hidden - returnRn (avails, item_avails, emptyNameSet) + returnRn (total_avails, item_avails, emptyNameSet) else -- Just item_avails imported; nothing to be hidden - returnRn (item_avails, [], availsToNameSet item_avails) - + returnRn (item_avails, [], explicits) where import_fm :: FiniteMap OccName AvailInfo import_fm = listToFM [ (nameOccName name, avail) - | avail <- avails, + | 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. + -- 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])] + 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 - | dodgy_import = addWarnRn (dodgyImportWarn mod item) `thenRn_` - returnRn filtered_avail - - | 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 - 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 - + maybe_filtered_avail = filterAvail item avail + Just filtered_avail = maybe_filtered_avail \end{code} @@ -421,88 +362,68 @@ filterImports mod (Just (want_hiding, import_items)) avails %* * %************************************************************************ -@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 unqualified import - -> Maybe Module -- 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 +mkEmptyExportAvails :: ModuleName -> ExportAvails +mkEmptyExportAvails mod_name = (unitFM mod_name [], emptyNameEnv) - -- Delete things that are hidden - name_env2 = foldl del_avail name_env1 hides +mkExportAvails :: ModuleName -> Bool -> GlobalRdrEnv -> [AvailInfo] -> ExportAvails +mkExportAvails mod_name unqual_imp gbl_env avails + = (mod_avail_env, entity_avail_env) + where + mod_avail_env = unitFM mod_name unqual_avails - -- Create the export-availability info - export_avails = mkExportAvails qual_mod unqual_imp name_env2 avails - in - returnRn (name_env2, export_avails) + -- unqual_avails is the Avails that are visible in *unqualfied* form + -- (1.4 Report, Section 5.1.1) + -- For example, in + -- import T hiding( f ) + -- we delete f from 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 (Qual qual_mod occ err_hif) better_name - env2 = addOneToGlobalRdrEnv env1 (Unqual occ) better_name - occ = nameOccName name - better_name = improve_prov name - - del_avail env avail = foldl delOneFromGlobalRdrEnv env rdr_names - where - rdr_names = map (Unqual . nameOccName) (availNames avail) - -err_hif = error "qualifyImports: hif" -- Not needed in key to mapping + unqual_avails | not unqual_imp = [] -- Short cut when no unqualified imports + | otherwise = mapMaybe prune avails + + prune (Avail n) | unqual_in_scope n = Just (Avail n) + prune (Avail n) | otherwise = Nothing + prune (AvailTC n ns) | null uqs = Nothing + | otherwise = Just (AvailTC n uqs) + where + uqs = filter unqual_in_scope ns + + unqual_in_scope n = unQualInScope gbl_env n + + entity_avail_env = mkNameEnv [ (name,avail) | avail <- avails, + name <- availNames avail] + +plusExportAvails :: ExportAvails -> ExportAvails -> ExportAvails +plusExportAvails (m1, e1) (m2, e2) + = (plusFM_C (++) m1 m2, plusAvailEnv e1 e2) + -- ToDo: wasteful: we do this once for each constructor! \end{code} %************************************************************************ %* * -\subsection{Export list processing +\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... +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 - = ([Module], -- 'module M's seen so far + = ([ModuleName], -- 'module M's seen so far ExportOccMap, -- Tracks exported occurrence names - NameEnv AvailInfo) -- The accumulated exported stuff, kept in an env + AvailEnv) -- The accumulated exported stuff, kept in an env -- so we can common-up related AvailInfos type ExportOccMap = FiniteMap OccName (Name, RdrNameIE) @@ -512,119 +433,106 @@ type ExportOccMap = FiniteMap OccName (Name, RdrNameIE) -- that have the same occurrence name -exportsFromAvail :: Module +exportsFromAvail :: ModuleName -> Maybe [RdrNameIE] -- Export spec -> ExportAvails - -> RnEnv - -> RnMG (Name -> ExportFlag, ExportEnv) + -> 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 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_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) - = foldlRn exports_from_item - ([], emptyFM, emptyNameEnv) export_items `thenRn` \ (_, _, export_avail_map) -> + 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 export_avails :: [AvailInfo] export_avails = nameEnvElts export_avail_map - - export_names :: NameSet - export_names = availsToNameSet export_avails - - -- Export only those fixities that are for names that are - -- (a) defined in this module - -- (b) exported - export_fixities :: [(Name,Fixity)] - export_fixities = [ (name,fixity) - | FixitySig name fixity _ <- nameEnvElts fixity_env, - name `elemNameSet` export_names, - isLocallyDefined name - ] - - export_fn :: Name -> ExportFlag - export_fn = mk_export_fn export_names in - returnRn (export_fn, ExportEnv export_avails export_fixities) + returnRn export_avails where - exports_from_item :: ExportAccum -> RdrNameIE -> RnMG ExportAccum + exports_from_item :: Bool -> ExportAccum -> RdrNameIE -> RnMG ExportAccum - exports_from_item acc@(mods, occs, avails) ie@(IEModuleContents mod) + exports_from_item warn_dups acc@(mods, occs, avails) ie@(IEModuleContents mod) | mod `elem` mods -- Duplicate export of M - = warnCheckRn opt_WarnDuplicateExports - (dupModuleExport mod) `thenRn_` + = warnCheckRn warn_dups (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' -> + Just mod_avails -> foldlRn (check_occs ie) occs mod_avails + `thenRn` \ occs' -> let - avails' = foldl add_avail avails mod_avails + avails' = foldl addAvail 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)) + exports_from_item warn_dups acc@(mods, occs, avails) ie + = lookupSrcName global_name_env (ieName ie) `thenRn` \ name -> - | not (null dup_names) - = addNameClashErrRn rdr_name (name:dup_names) `thenRn_` - returnRn acc + -- 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 ; -#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 + Just avail -> - | not enough_avail - = failWithRn acc (exportItemErr ie export_avail) + -- Filter out the bits we want + case filterAvail ie avail of { + Nothing -> -- Not enough availability + 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) + Just 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 - export_avail = filterAvail ie avail - enough_avail = case export_avail of {NotAvailable -> False; other -> True} + -- 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) + }} -add_avail avails avail = addToNameEnv_C plusAvail avails (availName avail) 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 - = foldlRn check occs (availNames avail) + = doptRn Opt_WarnDuplicateExports `thenRn` \ warn_dup_exports -> + foldlRn (check warn_dup_exports) occs (availNames avail) where - check occs name + 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 opt_WarnDuplicateExports - (dupExportWarn name_occ ie ie') `thenRn_` - returnRn occs + 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 - -mk_export_fn :: NameSet -> (Name -> ExportFlag) -mk_export_fn exported_names - = \name -> if name `elemNameSet` exported_names - then Exported - else NotExported \end{code} %************************************************************************ @@ -634,35 +542,40 @@ mk_export_fn exported_names %************************************************************************ \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)] - -dodgyImportWarn mod (IEThingAll tc) - = sep [ptext SLIT("Module") <+> quotes (pprModule mod) <+> ptext SLIT("exports") <+> quotes (ppr tc), - ptext SLIT("with no constructors/class operations;"), - ptext SLIT("yet it is imported with a (..)")] - + 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)] - -exportItemErr export_item NotAvailable - = sep [ ptext SLIT("Export item not in scope:"), quotes (ppr export_item)] + = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (ppr mod)] -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]]) +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") ] 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)] + = 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 (n:ns)))] + nest 4 (vcat (map ppr sorted_locs))] where - pp n = pprProvenance (getNameProvenance n) + sorted_locs = sortLt occ'ed_before (map nameSrcLoc (n:ns)) + occ'ed_before a b = LT == compare a b dupExportWarn occ_name ie1 ie2 = hsep [quotes (ppr occ_name), @@ -671,15 +584,10 @@ dupExportWarn occ_name ie1 ie2 dupModuleExport mod = hsep [ptext SLIT("Duplicate"), - quotes (ptext SLIT("Module") <+> pprModule mod), + quotes (ptext SLIT("Module") <+> ppr 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] - +moduleDeprec mod txt + = sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"), + nest 4 (ppr txt) ] \end{code}