X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnNames.lhs;h=f394f43fdf0d9c56c9edb2d1540106c97d5de56d;hb=98688c6e8fd33f31c51218cf93cbf03fe3a5e73d;hp=a5b0f848648f699f30657e966376d581c9903f58;hpb=9af77fa423926fbda946b31e174173d0ec5ebac8;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnNames.lhs b/ghc/compiler/rename/RnNames.lhs index a5b0f84..f394f43 100644 --- a/ghc/compiler/rename/RnNames.lhs +++ b/ghc/compiler/rename/RnNames.lhs @@ -6,46 +6,49 @@ \begin{code} module RnNames ( rnImports, importsFromLocalDecls, exportsFromAvail, - reportUnusedNames + reportUnusedNames, mkModDeps, exportsToAvails ) where #include "HsVersions.h" -import {-# SOURCE #-} RnHiFiles ( loadInterface ) - import CmdLineOpts ( DynFlag(..) ) - -import HsSyn ( HsDecl(..), IE(..), ieName, ImportDecl(..), - ForeignDecl(..), +import HsSyn ( IE(..), ieName, ImportDecl(..), + ForeignDecl(..), HsGroup(..), collectLocatedHsBinders, tyClDeclNames ) -import RdrHsSyn ( RdrNameIE, RdrNameImportDecl, RdrNameHsDecl ) +import RdrHsSyn ( RdrNameIE, RdrNameImportDecl, main_RDR_Unqual ) import RnEnv +import IfaceEnv ( lookupOrig, lookupImplicitOrig ) +import LoadIface ( loadSrcInterface ) import TcRnMonad import FiniteMap -import PrelNames ( pRELUDE_Name, mAIN_Name, isBuiltInSyntaxName ) +import PrelNames ( pRELUDE_Name, isBuiltInSyntaxName, isUnboundName ) import Module ( Module, ModuleName, moduleName, - moduleNameUserString, - unitModuleEnvByName, lookupModuleEnvByName, - moduleEnvElts ) -import Name ( Name, nameSrcLoc, nameOccName, nameModule ) + moduleNameUserString, isHomeModule, + unitModuleEnvByName, unitModuleEnv, + lookupModuleEnvByName, moduleEnvElts ) +import Name ( Name, nameSrcLoc, nameOccName, nameModuleName, + nameParent, nameParent_maybe, isExternalName ) import NameSet import NameEnv -import OccName ( OccName, dataName, isTcOcc ) -import HscTypes ( Provenance(..), ImportReason(..), GlobalRdrEnv, - GenAvailInfo(..), AvailInfo, Avails, IsBootInterface, - availName, availNames, availsToNameSet, - Deprecations(..), ModIface(..), - GlobalRdrElt(..), unQualInScope, isLocalGRE +import OccName ( OccName, srcDataName, isTcOcc ) +import HscTypes ( GenAvailInfo(..), AvailInfo, Avails, GhciMode(..), + IsBootInterface, IfaceExport, + availName, availNames, availsToNameSet, unQualInScope, + Deprecs(..), ModIface(..), Dependencies(..) ) -import RdrName ( rdrNameOcc, setRdrNameSpace, emptyRdrEnv, foldRdrEnv, isQual ) -import SrcLoc ( noSrcLoc ) +import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, + GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..), + emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts, + unQualOK, lookupGRE_Name, + Provenance(..), ImportSpec(..), + isLocalGRE, pprNameProvenance ) import Outputable -import Maybes ( maybeToBool, catMaybes ) +import Maybes ( isJust, isNothing, catMaybes, mapCatMaybes ) import ListSetOps ( removeDups ) import Util ( sortLt, notNull ) -import List ( partition ) +import List ( partition, insert ) import IO ( openFile, IOMode(..) ) \end{code} @@ -59,7 +62,7 @@ import IO ( openFile, IOMode(..) ) \begin{code} rnImports :: [RdrNameImportDecl] - -> TcRn m (GlobalRdrEnv, ImportAvails) + -> RnM (GlobalRdrEnv, ImportAvails) rnImports imports = -- PROCESS IMPORT DECLS @@ -73,7 +76,7 @@ rnImports imports (source, ordinary) = partition is_source_import all_imports is_source_import (ImportDecl _ is_boot _ _ _ _) = is_boot - get_imports = importsFromImportDecl (moduleName this_mod) + get_imports = importsFromImportDecl this_mod in mappM get_imports ordinary `thenM` \ stuff1 -> mappM get_imports source `thenM` \ stuff2 -> @@ -82,7 +85,7 @@ rnImports imports let (imp_gbl_envs, imp_avails) = unzip (stuff1 ++ stuff2) gbl_env :: GlobalRdrEnv - gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv imp_gbl_envs + gbl_env = foldr plusGlobalRdrEnv emptyGlobalRdrEnv imp_gbl_envs all_avails :: ImportAvails all_avails = foldr plusImportAvails emptyImportAvails imp_avails @@ -115,37 +118,40 @@ preludeImportDecl loc \end{code} \begin{code} -importsFromImportDecl :: ModuleName +importsFromImportDecl :: Module -> RdrNameImportDecl - -> TcRn m (GlobalRdrEnv, ImportAvails) + -> RnM (GlobalRdrEnv, ImportAvails) -importsFromImportDecl this_mod_name - (ImportDecl imp_mod_name is_boot qual_only as_mod import_spec iloc) +importsFromImportDecl this_mod + (ImportDecl imp_mod_name want_boot qual_only as_mod imp_details iloc) = addSrcLoc iloc $ - let - doc = ppr imp_mod_name <+> ptext SLIT("is directly imported") - in -- If there's an error in loadInterface, (e.g. interface -- file not found) we get lots of spurious errors from 'filterImports' - recoverM (returnM Nothing) - (loadInterface doc imp_mod_name (ImportByUser is_boot) `thenM` \ iface -> - returnM (Just iface)) `thenM` \ mb_iface -> + let + this_mod_name = moduleName this_mod + doc = ppr imp_mod_name <+> ptext SLIT("is directly imported") + in + loadSrcInterface doc imp_mod_name want_boot `thenM` \ iface -> - case mb_iface of { - Nothing -> returnM (emptyRdrEnv, emptyImportAvails ) ; - Just iface -> + -- Compiler sanity check: if the import didn't say + -- {-# SOURCE #-} we should not get a hi-boot file + WARN( not want_boot && mi_boot iface, ppr imp_mod_name ) + + -- Issue a user warning for a redundant {- SOURCE -} import + -- NB that we arrange to read all the ordinary imports before + -- any of the {- SOURCE -} imports + warnIf (want_boot && not (mi_boot iface)) + (warnRedundantSourceImport imp_mod_name) `thenM_` let - imp_mod = mi_module iface - avails_by_module = mi_exports iface - deprecs = mi_deprecs iface - dir_imp = unitModuleEnvByName imp_mod_name (imp_mod, import_all import_spec) - - avails :: Avails - avails = [ avail | (mod_name, avails) <- avails_by_module, - mod_name /= this_mod_name, - avail <- avails ] + imp_mod = mi_module iface + deprecs = mi_deprecs iface + is_orph = mi_orphan iface + deps = mi_deps iface + + filtered_exports = filter not_this_mod (mi_exports iface) + not_this_mod (mod,_) = mod /= this_mod_name -- 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 @@ -162,6 +168,66 @@ importsFromImportDecl this_mod_name -- import {-# SOURCE #-} A( AType ) -- -- then you'll get a 'B does not export AType' message. Oh well. + in + exportsToAvails filtered_exports `thenM` \ avails -> + + -- Filter the imports according to the import list + filterImports imp_mod want_boot imp_details avails `thenM` \ (filtered_avails, explicits) -> + + let + -- Compute new transitive dependencies + orphans | is_orph = insert imp_mod_name (dep_orphs deps) + | otherwise = dep_orphs deps + + (dependent_mods, dependent_pkgs) + | isHomeModule imp_mod + = -- Imported module is from the home package + -- Take its dependent modules and + -- (a) remove this_mod (might be there as a hi-boot) + -- (b) add imp_mod itself + -- Take its dependent packages unchanged + ((imp_mod_name, want_boot) : filter not_self (dep_mods deps), dep_pkgs deps) + + | otherwise + = -- Imported module is from another package + -- Dump the dependent modules + -- Add the package imp_mod comes from to the dependent packages + -- from imp_mod + ([], insert (mi_package iface) (dep_pkgs deps)) + + not_self (m, _) = m /= this_mod_name + + import_all = case imp_details of + Just (is_hiding, ls) -- Imports are spec'd explicitly + | not is_hiding -> Just (not (null ls)) + _ -> Nothing -- Everything is imported, + -- (or almost everything [hiding]) + + qual_mod_name = case as_mod of + Nothing -> imp_mod_name + Just another_name -> another_name + + -- 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. + imp_spec = ImportSpec { is_mod = imp_mod_name, is_qual = qual_only, + is_loc = iloc , is_as = qual_mod_name } + mk_deprec = mi_dep_fn iface + gres = [ GRE { gre_name = name, + gre_prov = Imported [imp_spec] (name `elemNameSet` explicits), + gre_deprec = mk_deprec name } + | avail <- filtered_avails, name <- availNames avail ] + gbl_env = mkGlobalRdrEnv gres + + avail_env = mkAvailEnv filtered_avails + imports = ImportAvails { + imp_qual = unitModuleEnvByName qual_mod_name avail_env, + imp_env = avail_env, + imp_mods = unitModuleEnv imp_mod (imp_mod, import_all), + imp_orphs = orphans, + imp_dep_mods = mkModDeps dependent_mods, + imp_dep_pkgs = dependent_pkgs } in -- Complain if we import a deprecated module @@ -171,24 +237,27 @@ importsFromImportDecl this_mod_name other -> returnM () ) `thenM_` - -- Filter the imports according to the import list - filterImports imp_mod_name is_boot import_spec avails `thenM` \ (filtered_avails, explicits) -> - - 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 deprecs - imports = mkImportAvails qual_mod unqual_imp gbl_env filtered_avails - in - returnM (gbl_env, imports { imp_mods = dir_imp}) - } + returnM (gbl_env, imports) -import_all (Just (False, _)) = False -- Imports are spec'd explicitly -import_all other = True -- Everything is imported +exportsToAvails :: [IfaceExport] -> TcRnIf gbl lcl Avails +exportsToAvails exports + = do { avails_by_module <- mappM do_one exports + ; return (concat avails_by_module) } + where + do_one (mod_name, exports) = mapM (do_avail mod_name) exports + do_avail mod (Avail n) = do { n' <- lookupOrig mod n; + ; return (Avail n') } + do_avail mod (AvailTC n ns) = do { n' <- lookupOrig mod n + ; ns' <- mappM (lookupImplicitOrig n') ns + ; return (AvailTC n' ns') } + -- Note the lookupImplicitOrig. It ensures that the subordinate names + -- record their parent; and that in turn ensures that the GlobalRdrEnv + -- has the correct parent for all the names in its range. + -- For imported things, we only suck in the binding site later, if ever. + +warnRedundantSourceImport mod_name + = ptext SLIT("Unnecessary {- SOURCE -} in the import of module") + <+> quotes (ppr mod_name) \end{code} @@ -206,15 +275,13 @@ created by its bindings. Complain about duplicate bindings \begin{code} -importsFromLocalDecls :: [RdrNameHsDecl] - -> TcRn m (GlobalRdrEnv, ImportAvails) -importsFromLocalDecls decls - = getModule `thenM` \ this_mod -> - mappM (getLocalDeclBinders this_mod) decls `thenM` \ avails_s -> +importsFromLocalDecls :: HsGroup RdrName + -> RnM (GlobalRdrEnv, ImportAvails) +importsFromLocalDecls group + = getModule `thenM` \ this_mod -> + getLocalDeclBinders this_mod group `thenM` \ avails -> -- 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] @@ -229,12 +296,12 @@ importsFromLocalDecls decls doptM Opt_NoImplicitPrelude `thenM` \ implicit_prelude -> 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 + mod_name = moduleName this_mod + prov = LocalDef mod_name + gbl_env = mkGlobalRdrEnv gres + gres = [ GRE { gre_name = name, gre_prov = prov, gre_deprec = Nothing} + | name <- all_names] + -- gre_deprecs = Nothing: don't deprecate 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 @@ -245,9 +312,9 @@ importsFromLocalDecls decls -- Optimisation: filter out names for built-in syntax -- They just clutter up the environment (esp tuples), and the parser -- will generate Exact RdrNames for them, so the cluttered - -- envt is no use. To avoid doing this filter all the type, + -- envt is no use. To avoid doing this filter all the time, -- we use -fno-implicit-prelude as a clue that the filter is - -- worth while. Really, it's only useful for Base and Tuple. + -- worth while. Really, it's only useful for GHC.Base and GHC.Tuple. -- -- It's worth doing because it makes the environment smaller for -- every module that imports the Prelude @@ -256,16 +323,23 @@ importsFromLocalDecls decls -- defn of gbl_env above). Stupid reason: when parsing -- data type decls, the constructors start as Exact tycon-names, -- and then get turned into data con names by zapping the name space; - -- but that stops them being Exact, so they get looked up. Sigh. - -- It doesn't matter because it only affects the Data.Tuple really. + -- but that stops them being Exact, so they get looked up. + -- Ditto in fixity decls; e.g. infix 5 : + -- Sigh. It doesn't matter because it only affects the Data.Tuple really. -- The important thing is to trim down the exports. - imports = mkImportAvails mod_name unqual_imp gbl_env avails' + avails' | implicit_prelude = filter not_built_in_syntax avails | otherwise = avails not_built_in_syntax a = not (all isBuiltInSyntaxName (availNames a)) -- Only filter it if all the names of the avail are built-in -- In particular, lists have (:) which is not built in syntax - -- so we don't filter it out. + -- so we don't filter it out. [Sept 03: wrong: see isBuiltInSyntaxName] + + avail_env = mkAvailEnv avails' + imports = emptyImportAvails { + imp_qual = unitModuleEnv this_mod avail_env, + imp_env = avail_env + } in returnM (gbl_env, imports) \end{code} @@ -284,35 +358,31 @@ files (@loadDecl@ calls @getTyClDeclBinders@). *** See "THE NAMING STORY" in HsDecls **** \begin{code} -getLocalDeclBinders :: Module -> RdrNameHsDecl -> TcRn m [AvailInfo] -getLocalDeclBinders mod (TyClD tycl_decl) +getLocalDeclBinders :: Module -> HsGroup RdrName -> RnM [AvailInfo] +getLocalDeclBinders mod (HsGroup {hs_valds = val_decls, + hs_tyclds = tycl_decls, + hs_fords = foreign_decls }) = -- 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. - mapM new (tyClDeclNames tycl_decl) `thenM` \ names@(main_name:_) -> - returnM [AvailTC main_name names] - where - new (nm,loc) = newTopBinder mod nm loc -getLocalDeclBinders mod (ValD binds) - = mappM new (collectLocatedHsBinders binds) `thenM` \ avails -> - returnM avails + mappM new_tc tycl_decls `thenM` \ tc_avails -> + mappM new_simple (for_hs_bndrs ++ val_hs_bndrs) `thenM` \ simple_avails -> + returnM (tc_avails ++ simple_avails) where - new (rdr_name, loc) = newTopBinder mod rdr_name loc `thenM` \ name -> + new_simple rdr_name = newTopSrcBinder mod Nothing rdr_name `thenM` \ name -> returnM (Avail name) -getLocalDeclBinders mod (ForD (ForeignImport nm _ _ _ loc)) - = newTopBinder mod nm loc `thenM` \ name -> - returnM [Avail name] -getLocalDeclBinders mod (ForD _) - = returnM [] - -getLocalDeclBinders mod (FixD _) = returnM [] -getLocalDeclBinders mod (DeprecD _) = returnM [] -getLocalDeclBinders mod (DefD _) = returnM [] -getLocalDeclBinders mod (InstD _) = returnM [] -getLocalDeclBinders mod (RuleD _) = returnM [] + val_hs_bndrs = collectLocatedHsBinders val_decls + for_hs_bndrs = [(nm,loc) | ForeignImport nm _ _ _ loc <- foreign_decls] + + new_tc tc_decl + = newTopSrcBinder mod Nothing main_rdr `thenM` \ main_name -> + mappM (newTopSrcBinder mod (Just main_name)) sub_rdrs `thenM` \ sub_names -> + returnM (AvailTC main_name (main_name : sub_names)) + where + (main_rdr : sub_rdrs) = tyClDeclNames tc_decl \end{code} @@ -326,11 +396,11 @@ getLocalDeclBinders mod (RuleD _) = returnM [] available, and filters it through the import spec (if any). \begin{code} -filterImports :: ModuleName -- The module being imported +filterImports :: Module -- The module being imported -> IsBootInterface -- Tells whether it's a {-# SOURCE #-} import -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding -> [AvailInfo] -- What's available - -> TcRn m ([AvailInfo], -- What's imported + -> RnM ([AvailInfo], -- What's imported NameSet) -- What was imported explicitly -- Complains if import spec mentions things that the module doesn't export @@ -365,7 +435,7 @@ filterImports mod from (Just (want_hiding, import_items)) total_avails bale_out item = addErr (badImportItemErr mod from item) `thenM_` returnM [] - get_item :: RdrNameIE -> TcRn m [(AvailInfo, [Name])] + get_item :: RdrNameIE -> RnM [(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 @@ -391,7 +461,7 @@ filterImports mod from (Just (want_hiding, import_items)) total_avails avails -> returnM [(a, []) | a <- avails] -- The 'explicits' list is irrelevant when hiding where - data_n = setRdrNameSpace n dataName + data_n = setRdrNameSpace n srcDataName get_item item = case check_item item of @@ -399,8 +469,8 @@ filterImports mod from (Just (want_hiding, import_items)) total_avails Just avail -> returnM [(avail, availNames avail)] check_item item - | not (maybeToBool maybe_in_import_avails) || - not (maybeToBool maybe_filtered_avail) + | isNothing maybe_in_import_avails || + isNothing maybe_filtered_avail = Nothing | otherwise @@ -487,65 +557,95 @@ type ExportOccMap = FiniteMap OccName (Name, RdrNameIE) -- that have the same occurrence name -exportsFromAvail :: Maybe [RdrNameIE] -> TcRn m Avails +exportsFromAvail :: Maybe Module -- Nothing => no 'module M(..) where' header at all + -> Maybe [RdrNameIE] -- Nothing => no explicit export list + -> RnM Avails -- Complains if two distinct exports have same OccName -- Warns about identical exports. -- Complains about exports items not in scope -exportsFromAvail Nothing - = do { this_mod <- getModule ; - if moduleName this_mod == mAIN_Name then - return [] - -- Export nothing; Main.$main is automatically exported - else - exportsFromAvail (Just [IEModuleContents (moduleName this_mod)]) - -- but for all other modules export everything. - } - -exportsFromAvail (Just exports) - = do { TcGblEnv { tcg_imports = imports } <- getGblEnv ; - warn_dup_exports <- doptM Opt_WarnDuplicateExports ; - exports_from_avail exports warn_dup_exports imports } - -exports_from_avail export_items warn_dup_exports - (ImportAvails { imp_unqual = mod_avail_env, - imp_env = entity_avail_env }) + +exportsFromAvail maybe_mod exports + = do { TcGblEnv { tcg_rdr_env = rdr_env, + tcg_imports = imports } <- getGblEnv ; + + -- If the module header is omitted altogether, then behave + -- as if the user had written "module Main(main) where..." + -- EXCEPT in interactive mode, when we behave as if he had + -- written "module Main where ..." + -- Reason: don't want to complain about 'main' not in scope + -- in interactive mode + ghci_mode <- getGhciMode ; + let { real_exports + = case maybe_mod of + Just mod -> exports + Nothing | ghci_mode == Interactive -> Nothing + | otherwise -> Just [IEVar main_RDR_Unqual] } ; + + exports_from_avail real_exports rdr_env imports } + +exports_from_avail Nothing rdr_env + imports@(ImportAvails { imp_env = entity_avail_env }) + = -- Export all locally-defined things + -- We do this by filtering the global RdrEnv, + -- keeping only things that are (a) qualified, + -- (b) locally defined, (c) a 'main' name + -- Then we look up in the entity-avail-env + return [ lookupAvailEnv entity_avail_env name + | gre <- globalRdrEnvElts rdr_env, + isLocalGRE gre, + let name = gre_name gre, + isNothing (nameParent_maybe name) -- Main things only + ] + +exports_from_avail (Just export_items) rdr_env + (ImportAvails { imp_qual = mod_avail_env, + imp_env = entity_avail_env }) = foldlM exports_from_item emptyExportAccum export_items `thenM` \ (_, _, export_avail_map) -> returnM (nameEnvElts export_avail_map) where - exports_from_item :: ExportAccum -> RdrNameIE -> TcRn m ExportAccum + exports_from_item :: ExportAccum -> RdrNameIE -> RnM ExportAccum exports_from_item acc@(mods, occs, avails) ie@(IEModuleContents mod) | mod `elem` mods -- Duplicate export of M - = warnIf warn_dup_exports (dupModuleExport mod) `thenM_` - returnM acc + = do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ; + warnIf warn_dup_exports (dupModuleExport mod) ; + returnM acc } | otherwise = case lookupModuleEnvByName mod_avail_env mod of - Nothing -> addErr (modExportErr mod) `thenM_` - returnM acc - Just mod_avails - -> foldlM (check_occs warn_dup_exports ie) - occs mod_avails `thenM` \ occs' -> - let + Nothing -> addErr (modExportErr mod) `thenM_` + returnM acc + + Just avail_env + -> let + mod_avails = [ filtered_avail + | avail <- availEnvElts avail_env, + let mb_avail = filter_unqual rdr_env avail, + isJust mb_avail, + let Just filtered_avail = mb_avail] + avails' = foldl addAvail avails mod_avails in + -- This check_occs not only finds conflicts between this item + -- and others, but also internally within this item. That is, + -- if 'M.x' is in scope in several ways, we'll have several + -- members of mod_avails with the same OccName. + + foldlM (check_occs ie) occs mod_avails `thenM` \ occs' -> returnM (mod:mods, occs', avails') exports_from_item acc@(mods, occs, avails) ie - = lookupGRE (ieName ie) `thenM` \ mb_gre -> - case mb_gre of { - Nothing -> addErr (unknownNameErr (ieName ie)) `thenM_` - returnM acc ; - Just gre -> - + = lookupGlobalOccRn (ieName ie) `thenM` \ name -> + if isUnboundName name then + returnM acc -- Avoid error cascade + else -- Get the AvailInfo for the parent of the specified name - case lookupAvailEnv entity_avail_env (gre_parent gre) of { - Nothing -> pprPanic "exportsFromAvail" - ((ppr (ieName ie)) <+> ppr gre) ; - Just avail -> - + let + parent = nameParent name + avail = lookupAvailEnv entity_avail_env parent + in -- Filter out the bits we want case filterAvail ie avail of { Nothing -> -- Not enough availability @@ -556,34 +656,55 @@ exports_from_avail export_items warn_dup_exports -- Phew! It's OK! Now to check the occurrence stuff! warnIf (not (ok_item ie avail)) (dodgyExportWarn ie) `thenM_` - check_occs warn_dup_exports ie occs export_avail `thenM` \ occs' -> + check_occs ie occs export_avail `thenM` \ occs' -> returnM (mods, occs', addAvail avails export_avail) - }}} + } + + +------------------------------- +filter_unqual :: GlobalRdrEnv -> AvailInfo -> Maybe AvailInfo +-- Filter the Avail by what's in scope unqualified +filter_unqual env (Avail n) + | in_scope env n = Just (Avail n) + | otherwise = Nothing +filter_unqual env (AvailTC n ns) + | not (null ns') = Just (AvailTC n ns') + | otherwise = Nothing + where + ns' = filter (in_scope env) ns +in_scope :: GlobalRdrEnv -> Name -> Bool +-- Checks whether the Name is in scope unqualified, +-- regardless of whether it's ambiguous or not +in_scope env n = any unQualOK (lookupGRE_Name env n) +------------------------------- 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 :: Bool -> RdrNameIE -> ExportOccMap -> AvailInfo -> TcRn m ExportOccMap -check_occs warn_dup_exports ie occs avail +------------------------------- +check_occs :: RdrNameIE -> ExportOccMap -> AvailInfo -> RnM ExportOccMap +check_occs ie occs avail = foldlM check occs (availNames avail) where check occs name = case lookupFM occs name_occ of - Nothing -> returnM (addToFM occs name_occ (name, ie)) + Nothing -> returnM (addToFM occs name_occ (name, ie)) + Just (name', ie') - | name == name' -> -- Duplicate export - warnIf warn_dup_exports - (dupExportWarn name_occ ie ie') - `thenM_` returnM occs - - | otherwise -> -- Same occ name but different names: an error - addErr (exportClashErr name_occ ie ie') `thenM_` - returnM occs + | name == name' -- Duplicate export + -> do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ; + warnIf warn_dup_exports (dupExportWarn name_occ ie ie') ; + returnM occs } + + | otherwise -- Same occ name but different names: an error + -> do { global_env <- getGlobalRdrEnv ; + addErr (exportClashErr global_env name name' ie ie') ; + returnM occs } where name_occ = nameOccName name \end{code} @@ -595,46 +716,45 @@ check_occs warn_dup_exports ie occs avail %********************************************************* \begin{code} -reportUnusedNames :: TcGblEnv - -> NameSet -- Used in this module - -> TcRn m () -reportUnusedNames gbl_env used_names - = warnUnusedModules unused_imp_mods `thenM_` - warnUnusedTopBinds bad_locals `thenM_` - warnUnusedImports bad_imports `thenM_` +reportUnusedNames :: TcGblEnv -> RnM () +reportUnusedNames gbl_env + = warnUnusedModules unused_imp_mods `thenM_` + warnUnusedTopBinds bad_locals `thenM_` + warnUnusedImports bad_imports `thenM_` printMinimalImports minimal_imports where - direct_import_mods :: [ModuleName] - direct_import_mods = map (moduleName . fst) - (moduleEnvElts (imp_mods (tcg_imports gbl_env))) - - -- Now, a use of C implies a use of T, - -- if C was brought into scope by T(..) or T(C) - really_used_names :: NameSet - really_used_names = used_names `unionNameSets` - mkNameSet [ gre_parent gre - | gre <- defined_names, - gre_name gre `elemNameSet` used_names] + used_names, all_used_names :: NameSet + used_names = findUses (tcg_dus gbl_env) emptyNameSet + all_used_names = used_names `unionNameSets` + mkNameSet (mapCatMaybes nameParent_maybe (nameSetToList used_names)) + -- A use of C implies a use of T, + -- if C was brought into scope by T(..) or T(C) -- Collect the defined names from the in-scope environment - -- Look for the qualified ones only, else get duplicates defined_names :: [GlobalRdrElt] - defined_names = foldRdrEnv add [] (tcg_rdr_env gbl_env) - add rdr_name ns acc | isQual rdr_name = ns ++ acc - | otherwise = acc + defined_names = globalRdrEnvElts (tcg_rdr_env gbl_env) defined_and_used, defined_but_not_used :: [GlobalRdrElt] - (defined_and_used, defined_but_not_used) = partition used defined_names - used gre = gre_name gre `elemNameSet` really_used_names + (defined_and_used, defined_but_not_used) = partition is_used defined_names + + is_used gre = gre_name gre `elemNameSet` all_used_names - -- Filter out the ones only defined implicitly + -- Filter out the ones that are + -- (a) defined in this module, and + -- (b) not defined by a 'deriving' clause + -- The latter have an Internal Name, so we can filter them out easily bad_locals :: [GlobalRdrElt] - bad_locals = filter isLocalGRE defined_but_not_used + bad_locals = filter is_bad defined_but_not_used + is_bad :: GlobalRdrElt -> Bool + is_bad gre = isLocalGRE gre && isExternalName (gre_name gre) bad_imports :: [GlobalRdrElt] bad_imports = filter bad_imp defined_but_not_used - bad_imp (GRE {gre_prov = NonLocalDef (UserImport mod _ True)}) = not (module_unused mod) - bad_imp other = False + bad_imp (GRE {gre_prov = Imported imp_specs True}) + = not (all (module_unused . is_mod) imp_specs) + -- Don't complain about unused imports if we've already said the + -- entire import is unused + bad_imp other = False -- To figure out the minimal set of imports, start with the things -- that are in scope (i.e. in gbl_env). Then just combine them @@ -662,17 +782,17 @@ reportUnusedNames gbl_env used_names -- We've carefully preserved the provenance so that we can -- construct minimal imports that import the name by (one of) -- the same route(s) as the programmer originally did. - add_name (GRE {gre_name = n, gre_parent = p, - gre_prov = NonLocalDef (UserImport m _ _)}) acc - = addToFM_C plusAvailEnv acc (moduleName m) - (unitAvailEnv (mk_avail n p)) + add_name (GRE {gre_name = n, + gre_prov = Imported imp_specs _}) acc + = addToFM_C plusAvailEnv acc (is_mod (head imp_specs)) + (unitAvailEnv (mk_avail n (nameParent_maybe n))) add_name other acc = acc -- n is the name of the thing, p is the name of its parent - mk_avail n p | n/=p = AvailTC p [p,n] - | isTcOcc (nameOccName p) = AvailTC n [n] - | otherwise = Avail n + mk_avail n (Just p) = AvailTC p [p,n] + mk_avail n Nothing | isTcOcc (nameOccName n) = AvailTC n [n] + | otherwise = Avail n add_inst_mod m acc | m `elemFM` acc = acc -- We import something already @@ -680,19 +800,37 @@ reportUnusedNames gbl_env used_names -- Add an empty collection of imports for a module -- from which we have sucked only instance decls + imports = tcg_imports gbl_env + + direct_import_mods :: [ModuleName] + direct_import_mods = map (moduleName . fst) + (moduleEnvElts (imp_mods imports)) + + hasEmptyImpList :: ModuleName -> Bool + hasEmptyImpList m = + case lookupModuleEnvByName (imp_mods imports) m of + Just (_,Just x) -> not x + _ -> False + -- unused_imp_mods are the directly-imported modules - -- that are not mentioned in minimal_imports + -- that are not mentioned in minimal_imports1 + -- [Note: not 'minimal_imports', because that includes direcly-imported + -- modules even if we use nothing from them; see notes above] unused_imp_mods = [m | m <- direct_import_mods, - not (maybeToBool (lookupFM minimal_imports m)), - m /= pRELUDE_Name] + isNothing (lookupFM minimal_imports1 m), + m /= pRELUDE_Name, + not (hasEmptyImpList m)] + -- hasEmptyImpList arranges not to complain about + -- import M (), which is an idiom for importing + -- instance declarations - module_unused :: Module -> Bool - module_unused mod = moduleName mod `elem` unused_imp_mods + module_unused :: ModuleName -> Bool + module_unused mod = mod `elem` unused_imp_mods -- ToDo: deal with original imports with 'qualified' and 'as M' clauses printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports - -> TcRn m () + -> RnM () printMinimalImports imps = ifOptM Opt_D_dump_minimal_imports $ do { @@ -708,14 +846,16 @@ printMinimalImports imps ppr_mod_ie (mod_name, ies) | mod_name == pRELUDE_Name = empty + | null ies -- Nothing except instances comes from here + = ptext SLIT("import") <+> ppr mod_name <> ptext SLIT("() -- Instances only") | otherwise = ptext SLIT("import") <+> ppr mod_name <> - parens (fsep (punctuate comma (map ppr ies))) + parens (fsep (punctuate comma (map ppr ies))) to_ies (mod, avail_env) = mappM to_ie (availEnvElts avail_env) `thenM` \ ies -> returnM (mod, ies) - to_ie :: AvailInfo -> TcRn m (IE Name) + to_ie :: AvailInfo -> RnM (IE Name) -- The main trick here is that if we're importing all the constructors -- we want to say "T(..)", but if we're importing only a subset we want -- to say "T(A,B,C)". So we have to find out what the module exports. @@ -723,18 +863,19 @@ printMinimalImports imps to_ie (AvailTC n [m]) = ASSERT( n==m ) returnM (IEThingAbs n) to_ie (AvailTC n ns) - = loadInterface (text "Compute minimal imports from" <+> ppr n_mod) - n_mod ImportBySystem `thenM` \ iface -> + = loadSrcInterface doc n_mod False `thenM` \ iface -> case [xs | (m,as) <- mi_exports iface, m == n_mod, AvailTC x xs <- as, - x == n] of - [xs] | all (`elem` ns) xs -> returnM (IEThingAll n) - | otherwise -> returnM (IEThingWith n (filter (/= n) ns)) - other -> pprTrace "to_ie" (ppr n <+> ppr (nameModule n) <+> ppr other) $ - returnM (IEVar n) + x == nameOccName n] of + [xs] | all_used xs -> returnM (IEThingAll n) + | otherwise -> returnM (IEThingWith n (filter (/= n) ns)) + other -> pprTrace "to_ie" (ppr n <+> ppr n_mod <+> ppr other) $ + returnM (IEVar n) where - n_mod = moduleName (nameModule n) + all_used avail_occs = all (`elem` map nameOccName ns) avail_occs + doc = text "Compute minimal imports from" <+> ppr n + n_mod = nameModuleName n \end{code} @@ -768,10 +909,20 @@ 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)] +exportClashErr global_env name1 name2 ie1 ie2 + = vcat [ ptext SLIT("Conflicting exports for") <+> quotes (ppr occ) <> colon + , ppr_export ie1 name1 + , ppr_export ie2 name2 ] + where + occ = nameOccName name1 + ppr_export ie name = nest 2 (quotes (ppr ie) <+> ptext SLIT("exports") <+> + quotes (ppr name) <+> pprNameProvenance (get_gre name)) + + -- get_gre finds a GRE for the Name, so that we can show its provenance + get_gre name + = case lookupGRE_Name global_env name of + (gre:_) -> gre + [] -> pprPanic "exportClashErr" (ppr name) dupDeclErr (n:ns) = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),