X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnNames.lhs;h=9197fd978dcc24ae03094db9faa62bb35bccee41;hb=d28ba8c800901bea01f70c4719278c2a364cf9fc;hp=d98dc2aca9d1b3a6477c4ae4e1b5674d74db472a;hpb=39262efa1c066d97547ac72d8bd16a145ac3f359;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnNames.lhs b/ghc/compiler/rename/RnNames.lhs index d98dc2a..9197fd9 100644 --- a/ghc/compiler/rename/RnNames.lhs +++ b/ghc/compiler/rename/RnNames.lhs @@ -5,272 +5,259 @@ \begin{code} module RnNames ( - getGlobalNames + rnImports, importsFromLocalDecls, exportsFromAvail, + reportUnusedNames, mkModDeps ) 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, getDeclSysBinders, - recordSlurp, checkUpToDate - ) +import {-# SOURCE #-} RnHiFiles ( loadInterface ) + +import CmdLineOpts ( DynFlag(..) ) + +import HsSyn ( IE(..), ieName, ImportDecl(..), + ForeignDecl(..), HsGroup(..), + collectLocatedHsBinders, tyClDeclNames + ) +import RdrHsSyn ( RdrNameIE, RdrNameImportDecl, main_RDR_Unqual ) import RnEnv -import RnMonad +import TcRnMonad import FiniteMap -import PrelMods -import PrelInfo ( main_RDR ) -import UniqFM ( lookupUFM ) -import Bag ( bagToList ) -import Maybes ( maybeToBool ) -import Module ( ModuleName, mkThisModule, pprModuleName, WhereFrom(..) ) +import PrelNames ( pRELUDE_Name, isBuiltInSyntaxName ) +import Module ( Module, ModuleName, ModuleEnv, moduleName, + moduleNameUserString, isHomeModule, + emptyModuleEnv, unitModuleEnvByName, unitModuleEnv, + lookupModuleEnvByName, extendModuleEnvByName, moduleEnvElts ) +import Name ( Name, nameSrcLoc, nameOccName, nameModule, isExternalName ) 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 NameEnv +import OccName ( OccName, srcDataName, isTcOcc ) +import HscTypes ( Provenance(..), ImportReason(..), GlobalRdrEnv, + GenAvailInfo(..), AvailInfo, Avails, GhciMode(..), + IsBootInterface, + availName, availNames, availsToNameSet, + Deprecations(..), ModIface(..), Dependencies(..), + GlobalRdrElt(..), unQualInScope, isLocalGRE, pprNameProvenance + ) +import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, lookupRdrEnv, rdrEnvToList, + emptyRdrEnv, foldRdrEnv, rdrEnvElts, mkRdrUnqual, isQual ) import Outputable -import Unique ( getUnique ) -import Util ( removeDups, equivClassesByUniq, sortLt ) -import List ( partition ) +import Maybe ( isJust, isNothing, catMaybes ) +import Maybes ( orElse ) +import ListSetOps ( removeDups ) +import Util ( sortLt, notNull ) +import List ( partition, insert ) +import IO ( openFile, IOMode(..) ) \end{code} %************************************************************************ %* * -\subsection{Get global names} + rnImports %* * %************************************************************************ \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, _) -> - - 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 - 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) -> +rnImports :: [RdrNameImportDecl] + -> TcRn m (GlobalRdrEnv, ImportAvails) - -- PROCESS IMPORT DECLS +rnImports imports + = -- PROCESS IMPORT DECLS -- Do the non {- SOURCE -} ones first, so that we get a helpful -- warning for {- SOURCE -} ones that are unnecessary + getModule `thenM` \ this_mod -> + getSrcLocM `thenM` \ loc -> + doptM Opt_NoImplicitPrelude `thenM` \ opt_no_prelude -> let + all_imports = mk_prel_imports this_mod loc opt_no_prelude ++ imports (source, ordinary) = partition is_source_import all_imports - is_source_import (ImportDecl _ ImportByUserSource _ _ _ _) = True - is_source_import other = False + is_source_import (ImportDecl _ is_boot _ _ _ _) = is_boot + + get_imports = importsFromImportDecl this_mod 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) -> + mappM get_imports ordinary `thenM` \ stuff1 -> + mappM get_imports source `thenM` \ stuff2 -> -- COMBINE RESULTS - -- We put the local env second, so that a local provenance - -- "wins", even if a module imports itself. let + (imp_gbl_envs, imp_avails) = unzip (stuff1 ++ stuff2) gbl_env :: GlobalRdrEnv - imp_gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv (imp_gbl_envs2 ++ imp_gbl_envs1) - gbl_env = imp_gbl_env `plusGlobalRdrEnv` local_gbl_env + gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv imp_gbl_envs - all_avails :: ExportAvails - all_avails = foldr plusExportAvails local_mod_avails (imp_avails_s2 ++ imp_avails_s1) + all_avails :: ImportAvails + all_avails = foldr plusImportAvails emptyImportAvails imp_avails in - - -- 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 -> - - -- 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 - ] - - -- CONSTRUCT RESULTS - export_mods = case exports of - Nothing -> [] - Just es -> [mod | IEModuleContents mod <- es, mod /= this_mod] - - export_env = ExportEnv exported_avails exported_fixities export_mods - (_, global_avail_env) = all_avails - in - traceRn (text "fixity env" <+> vcat (map ppr (nameEnvElts local_fixity_env))) `thenRn_` - - returnRn (Just (export_env, gbl_env, local_fixity_env, global_avail_env)) - } + -- ALL DONE + returnM (gbl_env, all_avails) 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 + -- because the former doesn't even look at Prelude.hi for instance + -- declarations, whereas the latter does. + mk_prel_imports this_mod loc no_prelude + | moduleName this_mod == pRELUDE_Name + || explicit_prelude_import + || no_prelude + = [] - 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 + | otherwise = [preludeImportDecl loc] - -- Unchanged source, and no errors yet; see if usage info - -- up to date, and exit if so - checkUpToDate mod `thenRn` \ up_to_date -> - (if up_to_date - then putDocRn (text "Compilation IS NOT required") - else returnRn ()) `thenRn_` - returnRn up_to_date + explicit_prelude_import + = notNull [ () | (ImportDecl mod _ _ _ _ _) <- imports, + mod == pRELUDE_Name ] + +preludeImportDecl loc + = ImportDecl pRELUDE_Name + False {- Not a boot interface -} + False {- Not qualified -} + Nothing {- No "as" -} + Nothing {- No import list -} + loc \end{code} \begin{code} -importsFromImportDecl :: (Name -> Bool) -- OK to omit qualifier +importsFromImportDecl :: Module -> RdrNameImportDecl - -> RnMG (GlobalRdrEnv, - ExportAvails) + -> TcRn m (GlobalRdrEnv, ImportAvails) -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) -> +importsFromImportDecl this_mod + (ImportDecl imp_mod_name is_boot qual_only as_mod imp_spec iloc) + = addSrcLoc iloc $ + let + doc = ppr imp_mod_name <+> ptext SLIT("is directly imported") + in - if null avails then - -- If there's an error in getInterfaceExports, (e.g. interface + -- If there's an error in loadInterface, (e.g. interface -- file not found) we get lots of spurious errors from 'filterImports' - returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name) - else + tryM (loadInterface doc imp_mod_name (ImportByUser is_boot)) `thenM` \ mb_iface -> - filterImports imp_mod_name import_spec avails - `thenRn` \ (filtered_avails, hides, explicits) -> + case mb_iface of { + Left exn -> returnM (emptyRdrEnv, emptyImportAvails ) ; + Right iface -> - -- 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 + imp_mod = mi_module iface + avails_by_module = mi_exports iface + deprecs = mi_deprecs iface + is_orph = mi_orphan iface + deps = mi_deps iface + + avails :: Avails + avails = [ avail | (mod_name, avails) <- avails_by_module, + mod_name /= this_mod_name, + avail <- avails ] + this_mod_name = moduleName this_mod + -- If the module exports anything defined in this module, just ignore it. + -- Reason: otherwise it looks as if there are two local definition sites + -- for the thing, and an error gets reported. Easiest thing is just to + -- filter them out up front. This situation only arises if a module + -- imports itself, or another module that imported it. (Necessarily, + -- this invoves a loop.) + -- + -- 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 - qualifyImports imp_mod_name - (not qual_only) -- Maybe want unqualified names - as_mod hides - filtered_avails improve_prov - `thenRn` \ (rdr_name_env, mod_avails) -> + -- Filter the imports according to the import list + filterImports imp_mod is_boot imp_spec avails `thenM` \ (filtered_avails, explicits) -> - returnRn (rdr_name_env, mod_avails) + 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, is_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_spec of + (Just (False, _)) -> False -- Imports are spec'd explicitly + other -> True -- 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. + avail_env = mkAvailEnv filtered_avails + + mk_prov name = NonLocalDef (UserImport imp_mod iloc (name `elemNameSet` explicits)) + gbl_env = mkGlobalRdrEnv qual_mod_name (not qual_only) + mk_prov filtered_avails deprecs + 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 + ifOptM Opt_WarnDeprecations ( + case deprecs of + DeprecAll txt -> addWarn (moduleDeprec imp_mod_name txt) + other -> returnM () + ) `thenM_` + + returnM (gbl_env, imports) + } + +mkModDeps :: [(ModuleName, IsBootInterface)] + -> ModuleEnv (ModuleName, IsBootInterface) +mkModDeps deps = foldl add emptyModuleEnv deps + where + add env elt@(m,_) = extendModuleEnvByName env m elt \end{code} -\begin{code} -importsFromLocalDecls mod_name rec_exp_fn decls - = mapRn (getLocalDeclBinders newLocalName) decls `thenRn` \ avails_s -> +%************************************************************************ +%* * + importsFromLocalDecls +%* * +%************************************************************************ - let - avails = concat avails_s +From the top-level declarations of this module produce + * the lexical environment + * the ImportAvails +created by its bindings. + +Complain about duplicate bindings +\begin{code} +importsFromLocalDecls :: HsGroup RdrName + -> TcRn m (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 all_names :: [Name] -- All the defns; no dups eliminated all_names = [name | avail <- avails, name <- availNames avail] @@ -278,86 +265,98 @@ importsFromLocalDecls mod_name rec_exp_fn decls (_, 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) 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. + mappM_ (addErr . dupDeclErr) dups `thenM_` - -- Build the environment - qualifyImports mod_name - True -- Want unqualified names - Nothing -- no 'as M' - [] -- Hide nothing - avails - (\n -> n) + doptM Opt_NoImplicitPrelude `thenM` \ implicit_prelude -> + let + mod_name = moduleName this_mod + mk_prov n = LocalDef -- Provenance is local + + unqual_imp = True -- Want unqualified names in scope + gbl_env = mkGlobalRdrEnv mod_name unqual_imp mk_prov avails NoDeprecs + -- NoDeprecs: don't complain about locally defined names + -- For a start, we may be exporting a deprecated thing + -- Also we may use a deprecated thing in the defn of another + -- deprecated things. We may even use a deprecated thing in + -- the defn of a non-deprecated thing, when changing a module's + -- interface + + + -- Optimisation: filter out names for built-in syntax + -- They just clutter up the environment (esp tuples), and the parser + -- will generate Exact RdrNames for them, so the cluttered + -- envt is no use. To avoid doing this filter all the time, + -- we use -fno-implicit-prelude as a clue that the filter is + -- worth while. Really, it's only useful for GHC.Base and GHC.Tuple. + -- + -- It's worth doing because it makes the environment smaller for + -- every module that imports the Prelude + -- + -- Note: don't filter the gbl_env (hence avails, not avails' in + -- 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. + -- The important thing is to trim down the exports. + + 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. + + avail_env = mkAvailEnv avails' + imports = emptyImportAvails { + imp_qual = unitModuleEnv this_mod avail_env, + imp_env = avail_env + } + in + returnM (gbl_env, imports) +\end{code} - where - mod = mkThisModule mod_name - newLocalName rdr_name loc - = (if isQual rdr_name then - qualNameErr (text "the binding for" <+> quotes (ppr rdr_name)) (rdr_name,loc) - -- There should never be a qualified name in a binding position (except in instance decls) - -- The parser doesn't check this because the same parser parses instance decls - else - returnRn ()) `thenRn_` +%********************************************************* +%* * +\subsection{Getting binders out of a declaration} +%* * +%********************************************************* - newLocalTopBinder mod (rdrNameOcc rdr_name) rec_exp_fn loc +@getLocalDeclBinders@ returns the names for a @RdrNameHsDecl@. It's +used for both source code (from @importsFromLocalDecls@) and interface +files (@loadDecl@ calls @getTyClDeclBinders@). + *** See "THE NAMING STORY" in HsDecls **** -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) - -getLocalDeclBinders new_name decl - = getDeclBinders new_name decl `thenRn` \ maybe_avail -> - case maybe_avail of - Nothing -> returnRn [] -- Instance decls and suchlike - Just avail -> getDeclSysBinders new_sys_name decl `thenRn_` - returnRn [avail] - where - -- The getDeclSysBinders is just to get the names of superclass selectors - -- etc, into the cache - new_sys_name rdr_name loc = newImplicitBinder (rdrNameOcc rdr_name) loc - -fixitiesFromLocalDecls :: GlobalRdrEnv -> [RdrNameHsDecl] -> RnMG FixityEnv -fixitiesFromLocalDecls gbl_env decls - = foldlRn getFixities emptyNameEnv decls +\begin{code} +getLocalDeclBinders :: Module -> HsGroup RdrName -> TcRn m [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. + + mappM new_tc tycl_decls `thenM` \ tc_avails -> + mappM new_bndr (for_hs_bndrs ++ val_hs_bndrs) `thenM` \ simple_bndrs -> + + returnM (tc_avails ++ map Avail simple_bndrs) 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:_) -> + new_bndr (rdr_name,loc) = newTopBinder mod rdr_name loc - -- Check for duplicate fixity decl - case lookupNameEnv acc name of { - Just (FixitySig _ _ loc') -> addErrRn (dupFixityDecl rdr_name loc loc') - `thenRn_` returnRn acc ; + val_hs_bndrs = collectLocatedHsBinders val_decls + for_hs_bndrs = [(nm,loc) | ForeignImport nm _ _ _ loc <- foreign_decls] - Nothing -> returnRn (addToNameEnv acc name (FixitySig name fixity loc)) - }} + new_tc tc_decl = mappM new_bndr (tyClDeclNames tc_decl) `thenM` \ names@(main_name:_) -> + returnM (AvailTC main_name names) \end{code} + %************************************************************************ %* * \subsection{Filtering imports} @@ -368,55 +367,85 @@ fixitiesFromLocalDecls gbl_env decls 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 - -> RnMG ([AvailInfo], -- What's actually imported - [AvailInfo], -- What's to be hidden - -- (the unqualified version, that is) + -> TcRn m ([AvailInfo], -- What's imported NameSet) -- What was imported explicitly -- Complains if import spec mentions things that the module doesn't export -- Warns/informs if import spec contains duplicates. -filterImports mod Nothing imports - = returnRn (imports, [], emptyNameSet) +filterImports mod from Nothing imports + = returnM (imports, emptyNameSet) -filterImports mod (Just (want_hiding, import_items)) avails - = mapMaybeRn check_item import_items `thenRn` \ avails_w_explicits -> +filterImports mod from (Just (want_hiding, import_items)) total_avails + = mappM get_item import_items `thenM` \ avails_w_explicits_s -> let - (item_avails, explicits_s) = unzip avails_w_explicits + (item_avails, explicits_s) = unzip (concat avails_w_explicits_s) explicits = foldl addListToNameSet emptyNameSet explicits_s in - if want_hiding - then - -- All imported; item_avails to be hidden - returnRn (avails, item_avails, emptyNameSet) + if want_hiding then + let -- All imported; item_avails to be hidden + hidden = availsToNameSet item_avails + keep n = not (n `elemNameSet` hidden) + in + returnM (pruneAvails keep total_avails, emptyNameSet) else -- Just item_avails imported; nothing to be hidden - returnRn (item_avails, [], explicits) + returnM (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. - check_item item@(IEModuleContents _) - = addErrRn (badImportItemErr mod item) `thenRn_` - returnRn Nothing + bale_out item = addErr (badImportItemErr mod from item) `thenM_` + returnM [] + + get_item :: RdrNameIE -> TcRn m [(AvailInfo, [Name])] + -- Empty list for a bad item. + -- Singleton is typical case. + -- Can have two when we are hiding, and mention C which might be + -- both a class and a data constructor. + -- The [Name] is the list of explicitly-mentioned names + get_item item@(IEModuleContents _) = bale_out item + + get_item item@(IEThingAll _) + = case check_item item of + Nothing -> bale_out item + Just avail@(AvailTC _ [n]) -> -- This occurs when you import T(..), but + -- only export T abstractly. The single [n] + -- in the AvailTC is the type or class itself + ifOptM Opt_WarnMisc (addWarn (dodgyImportWarn mod item)) `thenM_` + returnM [(avail, [availName avail])] + Just avail -> returnM [(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 -> returnM [(a, []) | a <- avails] + -- The 'explicits' list is irrelevant when hiding + where + data_n = setRdrNameSpace n srcDataName - check_item item - | not (maybeToBool maybe_in_import_avails) || - not (maybeToBool maybe_filtered_avail) - = addErrRn (badImportItemErr mod item) `thenRn_` - returnRn Nothing + get_item item + = case check_item item of + Nothing -> bale_out item + Just avail -> returnM [(avail, availNames avail)] - | dodgy_import = addWarnRn (dodgyImportWarn mod item) `thenRn_` - returnRn (Just (filtered_avail, explicits)) + check_item item + | isNothing maybe_in_import_avails || + isNothing maybe_filtered_avail + = Nothing - | otherwise = returnRn (Just (filtered_avail, explicits)) + | otherwise + = Just filtered_avail where wanted_occ = rdrNameOcc (ieName item) @@ -425,86 +454,43 @@ filterImports mod (Just (want_hiding, import_items)) avails 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) - +filterAvail :: RdrNameIE -- Wanted + -> AvailInfo -- Available + -> Maybe AvailInfo -- Resulting available; + -- Nothing if (any of the) wanted stuff isn't there + +filterAvail ie@(IEThingWith want wants) avail@(AvailTC n ns) + | sub_names_ok = Just (AvailTC n (filter is_wanted ns)) + | otherwise = Nothing 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) + is_wanted name = nameOccName name `elem` wanted_occs + sub_names_ok = all (`elem` avail_occs) wanted_occs + avail_occs = map nameOccName ns + wanted_occs = map rdrNameOcc (want:wants) + +filterAvail (IEThingAbs _) (AvailTC n ns) = ASSERT( n `elem` ns ) + Just (AvailTC n [n]) + +filterAvail (IEThingAbs _) avail@(Avail n) = Just avail -- Type synonyms + +filterAvail (IEVar _) avail@(Avail n) = Just avail +filterAvail (IEVar v) avail@(AvailTC n ns) = Just (AvailTC n (filter wanted ns)) + where + wanted n = nameOccName n == occ + occ = rdrNameOcc v + -- The second equation happens if we import a class op, thus + -- import A( op ) + -- where op is a class operation + +filterAvail (IEThingAll _) avail@(AvailTC _ _) = Just avail + -- We don't complain even if the IE says T(..), but + -- no constrs/class ops of T are available + -- Instead that's caught with a warning by the caller + +filterAvail ie avail = Nothing \end{code} @@ -516,23 +502,24 @@ qualifyImports this_mod unqual_imp as_mod hides 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). +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... +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 + AvailEnv) -- The accumulated exported stuff, kept in an env -- so we can common-up related AvailInfos +emptyExportAccum = ([], emptyFM, emptyAvailEnv) type ExportOccMap = FiniteMap OccName (Name, RdrNameIE) -- Tracks what a particular exported OccName @@ -541,113 +528,328 @@ type ExportOccMap = FiniteMap OccName (Name, RdrNameIE) -- that have the same occurrence name -exportsFromAvail :: ModuleName - -> Maybe [RdrNameIE] -- Export spec - -> ExportAvails - -> GlobalRdrEnv - -> RnMG Avails +exportsFromAvail :: Maybe Module -- Nothing => no 'module M(..) where' header at all + -> Maybe [RdrNameIE] -- Nothing => no explicit export list + -> TcRn m 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 + +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 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 + | (rdr_name, gres) <- rdrEnvToList rdr_env, + isQual rdr_name, -- Avoid duplicates + GRE { gre_name = name, + gre_parent = Nothing, -- Main things only + gre_prov = LocalDef } <- gres + ] + +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 -> RnMG ExportAccum + exports_from_item :: ExportAccum -> RdrNameIE -> TcRn m 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 + = do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ; + warnIf warn_dup_exports (dupModuleExport mod) ; + returnM 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') + = case lookupModuleEnvByName mod_avail_env mod of + 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 - | 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 + = lookupGRE (ieName ie) `thenM` \ mb_gre -> + case mb_gre of { + Nothing -> addErr (unknownNameErr (ieName ie)) `thenM_` + returnM acc ; + Just gre -> + + -- Get the AvailInfo for the parent of the specified name + let + parent = gre_parent gre `orElse` gre_name gre + avail = lookupAvailEnv entity_avail_env parent + in + -- Filter out the bits we want + case filterAvail ie avail of { + Nothing -> -- Not enough availability + addErr (exportItemErr ie) `thenM_` + returnM acc ; + + Just export_avail -> + + -- Phew! It's OK! Now to check the occurrence stuff! + warnIf (not (ok_item ie avail)) (dodgyExportWarn ie) `thenM_` + 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 + = case lookupRdrEnv env (mkRdrUnqual (nameOccName n)) of + Nothing -> False + Just gres -> or [n == gre_name g | g <- gres] + + +------------------------------- +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 -> TcRn m ExportOccMap check_occs ie occs avail - = foldlRn check occs (availNames avail) + = foldlM 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 + Nothing -> returnM (addToFM occs name_occ (name, ie)) - | otherwise -> -- Same occ name but different names: an error - failWithRn occs (exportClashErr name_occ ie ie') + Just (name', ie') + | 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 - -mk_export_fn :: NameSet -> (Name -> ExportFlag) -mk_export_fn exported_names - = \name -> if name `elemNameSet` exported_names - then Exported - else NotExported \end{code} +%********************************************************* +%* * +\subsection{Unused names} +%* * +%********************************************************* + +\begin{code} +reportUnusedNames :: TcGblEnv -> DefUses -> TcRn m () +reportUnusedNames gbl_env dus + = warnUnusedModules unused_imp_mods `thenM_` + warnUnusedTopBinds bad_locals `thenM_` + warnUnusedImports bad_imports `thenM_` + printMinimalImports minimal_imports + where + used_names :: NameSet + used_names = findUses dus emptyNameSet + + -- 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_and_used, defined_but_not_used :: [GlobalRdrElt] + (defined_and_used, defined_but_not_used) = partition is_used defined_names + + is_used gre = n `elemNameSet` used_names || any (`elemNameSet` used_names) kids + -- The 'kids' part is because a use of C implies a use of T, + -- if C was brought into scope by T(..) or T(C) + where + n = gre_name gre + kids = case lookupAvailEnv_maybe avail_env n of + Just (AvailTC n ns) -> ns + other -> [] -- Ids, class ops and datacons + -- (The latter two give Nothing) + + -- 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 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 + + -- 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 + -- into a bunch of avails, so they are properly grouped + minimal_imports :: FiniteMap ModuleName AvailEnv + minimal_imports0 = emptyFM + minimal_imports1 = foldr add_name minimal_imports0 defined_and_used + minimal_imports = foldr add_inst_mod minimal_imports1 direct_import_mods + -- The last line makes sure that we retain all direct imports + -- even if we import nothing explicitly. + -- It's not necessarily redundant to import such modules. Consider + -- module This + -- import M () + -- + -- The import M() is not *necessarily* redundant, even if + -- we suck in no instance decls from M (e.g. it contains + -- no instance decls, or This contains no code). It may be + -- that we import M solely to ensure that M's orphan instance + -- decls (or those in its imports) are visible to people who + -- import This. Sigh. + -- There's really no good way to detect this, so the error message + -- in RnEnv.warnUnusedModules is weakened instead + + + -- 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 other acc + = acc + + -- n is the name of the thing, p is the name of its parent + mk_avail n (Just p) = AvailTC p [p,n] + mk_avail n Nothing | isTcOcc (nameOccName n) = AvailTC n [n] + | otherwise = Avail n + + add_inst_mod m acc + | m `elemFM` acc = acc -- We import something already + | otherwise = addToFM acc m emptyAvailEnv + -- Add an empty collection of imports for a module + -- from which we have sucked only instance decls + + imports = tcg_imports gbl_env + avail_env = imp_env imports + + direct_import_mods :: [ModuleName] + direct_import_mods = map (moduleName . fst) + (moduleEnvElts (imp_mods imports)) + + -- unused_imp_mods are the directly-imported modules + -- 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, + isNothing (lookupFM minimal_imports1 m), + m /= pRELUDE_Name] + + module_unused :: Module -> Bool + module_unused mod = moduleName mod `elem` unused_imp_mods + + +-- ToDo: deal with original imports with 'qualified' and 'as M' clauses +printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports + -> TcRn m () +printMinimalImports imps + = ifOptM Opt_D_dump_minimal_imports $ do { + + mod_ies <- mappM to_ies (fmToList imps) ; + this_mod <- getModule ; + rdr_env <- getGlobalRdrEnv ; + ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ; + printForUser h (unQualInScope rdr_env) + (vcat (map ppr_mod_ie mod_ies)) }) + } + where + mkFilename this_mod = moduleNameUserString (moduleName this_mod) ++ ".imports" + 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))) + + to_ies (mod, avail_env) = mappM to_ie (availEnvElts avail_env) `thenM` \ ies -> + returnM (mod, ies) + + to_ie :: AvailInfo -> TcRn m (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. + to_ie (Avail n) = returnM (IEVar n) + 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 -> + 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) + where + n_mod = moduleName (nameModule n) +\end{code} + + %************************************************************************ %* * \subsection{Errors} @@ -655,36 +857,56 @@ mk_export_fn exported_names %************************************************************************ \begin{code} -badImportItemErr mod ie - = sep [ptext SLIT("Module"), quotes (pprModuleName 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 (pprModuleName 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 + True -> 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 (pprModuleName mod)] + = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (ppr mod)] exportItemErr export_item - = sep [ ptext SLIT("Bad export item"), quotes (ppr 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, in a very inefficient way + -- There isn't a more efficient way to do it, because we don't necessarily + -- know the RdrName under which this Name is in scope. So we just + -- search linearly. Shouldn't matter because this only happens + -- in an error message. + get_gre name + = case [gre | gres <- rdrEnvElts global_env, + gre <- gres, + gre_name gre == name] of + (gre:_) -> gre + [] -> pprPanic "exportClashErr" (ppr name) dupDeclErr (n:ns) = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n), - nest 4 (vcat (map pp sorted_ns))] + nest 4 (vcat (map ppr sorted_locs))] 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) + 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), @@ -693,15 +915,10 @@ dupExportWarn occ_name ie1 ie2 dupModuleExport mod = hsep [ptext SLIT("Duplicate"), - quotes (ptext SLIT("Module") <+> pprModuleName 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}