X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnNames.lhs;h=2eb5a8de42de0c3f26ed1f548363c92af78274cf;hb=d191be5da8d2934a5c50bdbc605784d6a9043b6f;hp=05d9e5afb2186bfc5481e76b6dc012429f3c31b7;hpb=12899612693163154531da3285ec99c1c8ca2226;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnNames.lhs b/ghc/compiler/rename/RnNames.lhs index 05d9e5a..656d131 100644 --- a/ghc/compiler/rename/RnNames.lhs +++ b/ghc/compiler/rename/RnNames.lhs @@ -1,1060 +1,1036 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[RnNames]{Extracting imported and top-level names in scope} \begin{code} -#include "HsVersions.h" - module RnNames ( - getGlobalNames, - SYN_IE(GlobalNameInfo) + rnImports, importsFromLocalDecls, exportsFromAvail, + reportUnusedNames, reportDeprecations, + mkModDeps, exportsToAvails ) where -import PreludeGlaST ( SYN_IE(MutableVar) ) - -IMP_Ubiq() - -import HsSyn -import RdrHsSyn -import RnHsSyn +#include "HsVersions.h" -import RnMonad -import RnIfaces ( IfaceCache, cachedIface, cachedDecl, CachingResult(..) ) -import RnUtils ( SYN_IE(RnEnv), emptyRnEnv, initRnEnv, extendGlobalRnEnv, - lubExportFlag, qualNameErr, dupNamesErr, pprRnEnv - ) -import ParseUtils ( ParsedIface(..), RdrIfaceDecl(..), ExportsMap(..), RdrIfaceInst ) - - -import Bag ( emptyBag, unitBag, consBag, snocBag, unionBags, - unionManyBags, mapBag, foldBag, filterBag, listToBag, bagToList ) -import CmdLineOpts ( opt_NoImplicitPrelude, opt_CompilingGhcInternals ) -import ErrUtils ( SYN_IE(Error), SYN_IE(Warning), addErrLoc, addShortErrLocLine, addShortWarnLocLine ) -import FiniteMap ( emptyFM, addToFM, addListToFM, lookupFM, fmToList, eltsFM, delListFromFM, keysFM{-ToDo:rm-}, FiniteMap ) -import Id ( GenId ) -import Maybes ( maybeToBool, catMaybes, MaybeErr(..) ) -import Name ( RdrName(..), Name, isQual, mkTopLevName, mkWiredInName, origName, - nameOf, qualToOrigName, mkImportedName, - nameExportFlag, nameImportFlag, - getLocalName, getSrcLoc, getImpLocs, - moduleNamePair, pprNonSym, - isLexCon, isLexSpecialSym, ExportFlag(..), OrigName(..) +import CmdLineOpts ( DynFlag(..) ) +import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl, + ForeignDecl(..), HsGroup(..), + collectGroupBinders, tyClDeclNames ) -import PrelInfo ( SYN_IE(BuiltinNames), SYN_IE(BuiltinKeys) ) -import PrelMods ( pRELUDE, gHC_BUILTINS, modulesWithBuiltins ) -import Pretty -import SrcLoc ( SrcLoc, mkBuiltinSrcLoc ) -import TyCon ( tyConDataCons ) -import UniqFM ( emptyUFM, addListToUFM_C, lookupUFM ) -import UniqSupply ( splitUniqSupply ) -import Util ( isIn, assoc, cmpPString, sortLt, removeDups, - equivClasses, panic, assertPanic, pprPanic{-ToDo:rm-}, pprTrace{-ToDo:rm-} +import RnEnv +import IfaceEnv ( lookupOrig, newGlobalBinder ) +import LoadIface ( loadSrcInterface ) +import TcRnMonad + +import FiniteMap +import PrelNames ( pRELUDE_Name, isBuiltInSyntaxName, isUnboundName, + main_RDR_Unqual ) +import Module ( Module, ModuleName, moduleName, mkPackageModule, + moduleNameUserString, isHomeModule, + unitModuleEnvByName, unitModuleEnv, + lookupModuleEnvByName, moduleEnvElts ) +import Name ( Name, nameSrcLoc, nameOccName, nameModuleName, + nameParent, nameParent_maybe, isExternalName, nameModule ) +import NameSet +import NameEnv +import OccName ( srcDataName, isTcOcc, occNameFlavour, OccEnv, + mkOccEnv, lookupOccEnv, emptyOccEnv, extendOccEnv ) +import HscTypes ( GenAvailInfo(..), AvailInfo, Avails, GhciMode(..), + IfaceExport, HomePackageTable, PackageIfaceTable, + availName, availNames, availsToNameSet, unQualInScope, + Deprecs(..), ModIface(..), Dependencies(..), lookupIface, + ExternalPackageState(..) ) -import PprStyle --ToDo:rm +import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, + GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..), + emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts, + unQualOK, lookupGRE_Name, + Provenance(..), ImportSpec(..), + isLocalGRE, pprNameProvenance ) +import Outputable +import Maybes ( isJust, isNothing, catMaybes, mapCatMaybes, seqMaybe ) +import SrcLoc ( noSrcLoc, Located(..), mkGeneralSrcSpan, + unLoc, noLoc ) +import BasicTypes ( DeprecTxt ) +import ListSetOps ( removeDups ) +import Util ( sortLt, notNull, isSingleton ) +import List ( partition, insert ) +import IO ( openFile, IOMode(..) ) \end{code} -\begin{code} -type GlobalNameInfo = (BuiltinNames, - BuiltinKeys, - Name -> ExportFlag, -- export flag - Name -> [RdrName]) -- occurrence names - -- NB: both of the functions are in a *knot* and - -- must be tugged on oh-so-gently... - -type RnM_Info s r = RnMonad GlobalNameInfo s r - -getGlobalNames :: - IfaceCache - -> GlobalNameInfo - -> UniqSupply - -> RdrNameHsModule - -> IO (RnEnv, - [Module], -- directly imported modules - Bag (Module,RnName), -- unqualified imports from module - Bag RenamedFixityDecl, -- imported fixity decls - Bag Error, - Bag Warning) - -getGlobalNames iface_cache info us - (HsModule mod _ _ imports _ ty_decls _ cls_decls _ _ _ binds _ _) - = let - (us1, us2) = splitUniqSupply us - in - case initRn True mod emptyRnEnv us1 - (setExtraRn info $ - getSourceNames ty_decls cls_decls binds) - of { ((src_vals, src_tcs), src_errs, src_warns) -> - doImportDecls iface_cache info us2 imports >>= - \ (imp_vals, imp_tcs, imp_mods, unqual_imps, imp_fixes, imp_errs, imp_warns) -> - let - unqual_vals = map (\rn -> (Unqual (getLocalName rn), rn)) (bagToList src_vals) - unqual_tcs = map (\rn -> (Unqual (getLocalName rn), rn)) (bagToList src_tcs) +%************************************************************************ +%* * + rnImports +%* * +%************************************************************************ - (src_env, src_dups) = extendGlobalRnEnv initRnEnv unqual_vals unqual_tcs - (all_env, imp_dups) = extendGlobalRnEnv src_env (bagToList imp_vals) (bagToList imp_tcs) +\begin{code} +rnImports :: [LImportDecl RdrName] + -> RnM (GlobalRdrEnv, ImportAvails) + +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 -> + doptM Opt_NoImplicitPrelude `thenM` \ opt_no_prelude -> + let + all_imports = mk_prel_imports this_mod opt_no_prelude ++ imports + (source, ordinary) = partition is_source_import all_imports + is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot - -- remove dups of the same imported thing - diff_imp_dups = filterBag diff_orig imp_dups - diff_orig (_,rn1,rn2) = origName "diff_orig" rn1 /= origName "diff_orig" rn2 + get_imports = importsFromImportDecl this_mod + in + mappM get_imports ordinary `thenM` \ stuff1 -> + mappM get_imports source `thenM` \ stuff2 -> - all_dups = bagToList (src_dups `unionBags` diff_imp_dups) - dup_errs = map dup_err (equivClasses cmp_rdr all_dups) - cmp_rdr (rdr1,_,_) (rdr2,_,_) = cmp rdr1 rdr2 - dup_err ((rdr,rn1,rn2):rest) = globalDupNamesErr rdr (rn1:rn2: [rn|(_,_,rn)<-rest]) + -- COMBINE RESULTS + let + (imp_gbl_envs, imp_avails) = unzip (stuff1 ++ stuff2) + gbl_env :: GlobalRdrEnv + gbl_env = foldr plusGlobalRdrEnv emptyGlobalRdrEnv imp_gbl_envs - all_errs = src_errs `unionBags` imp_errs `unionBags` listToBag dup_errs - all_warns = src_warns `unionBags` imp_warns - in --- pprTrace "initRnEnv:" (pprRnEnv PprDebug initRnEnv) $ --- pprTrace "src_env:" (pprRnEnv PprDebug src_env) $ --- pprTrace "all_env:" (pprRnEnv PprDebug all_env) $ - return (all_env, imp_mods, unqual_imps, imp_fixes, all_errs, all_warns) } + all_avails :: ImportAvails + all_avails = foldr plusImportAvails emptyImportAvails imp_avails + in + -- ALL DONE + returnM (gbl_env, all_avails) + where + -- 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. + mk_prel_imports this_mod no_prelude + | moduleName this_mod == pRELUDE_Name + || explicit_prelude_import + || no_prelude + = [] + + | otherwise = [preludeImportDecl] + + explicit_prelude_import + = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports, + unLoc mod == pRELUDE_Name ] + +preludeImportDecl + = L loc $ + ImportDecl (L loc pRELUDE_Name) + False {- Not a boot interface -} + False {- Not qualified -} + Nothing {- No "as" -} + Nothing {- No import list -} + where + loc = mkGeneralSrcSpan FSLIT("Implicit import declaration") \end{code} + +\begin{code} +importsFromImportDecl :: Module + -> LImportDecl RdrName + -> RnM (GlobalRdrEnv, ImportAvails) -********************************************************* -* * -\subsection{Top-level source names} -* * -********************************************************* +importsFromImportDecl this_mod + (L loc (ImportDecl loc_imp_mod_name want_boot qual_only as_mod imp_details)) + = + addSrcSpan loc $ -\begin{code} -getSourceNames :: -- Collects global *binders* (not uses) - [RdrNameTyDecl] - -> [RdrNameClassDecl] - -> RdrNameHsBinds - -> RnM_Info s (Bag RnName, -- values - Bag RnName) -- tycons/classes - -getSourceNames ty_decls cls_decls binds - = mapAndUnzip3Rn getTyDeclNames ty_decls `thenRn` \ (tycon_s, constrs_s, fields_s) -> - mapAndUnzipRn getClassNames cls_decls `thenRn` \ (cls_s, cls_ops_s) -> - getTopBindsNames binds `thenRn` \ bind_names -> - returnRn (unionManyBags constrs_s `unionBags` - unionManyBags fields_s `unionBags` - unionManyBags cls_ops_s `unionBags` bind_names, - listToBag tycon_s `unionBags` listToBag cls_s) - --------------- -getTyDeclNames :: RdrNameTyDecl - -> RnM_Info s (RnName, Bag RnName, Bag RnName) -- tycon, constrs and fields - -getTyDeclNames (TyData _ tycon _ condecls _ _ src_loc) - = --getExtraRn `thenRn` \ ((b_val_names,b_tc_names),b_keys,rec_exp_fn,rec_occ_fn) -> - --pprTrace "getTyDeclNames:" (ppr PprDebug tycon) $ - --pprTrace "getTDN1:" (ppAboves [ ppCat [ppPStr m, ppPStr n] | ((OrigName m n), _) <- fmToList b_tc_names]) $ - - newGlobalName src_loc Nothing False{-not val-} tycon `thenRn` \ tycon_name -> - getConFieldNames (Just (nameExportFlag tycon_name)) emptyBag emptyBag emptyFM - condecls `thenRn` \ (con_names, field_names) -> - let - rn_tycon = RnData tycon_name con_names field_names - rn_constrs = [ RnConstr name tycon_name | name <- con_names] - rn_fields = [ RnField name tycon_name | name <- field_names] - in - returnRn (rn_tycon, listToBag rn_constrs, listToBag rn_fields) - -getTyDeclNames (TyNew _ tycon _ [NewConDecl con _ con_loc] _ _ src_loc) - = newGlobalName src_loc Nothing False{-not val-} tycon `thenRn` \ tycon_name -> - newGlobalName con_loc (Just (nameExportFlag tycon_name)) True{-val-} con - `thenRn` \ con_name -> - returnRn (RnData tycon_name [con_name] [], - unitBag (RnConstr con_name tycon_name), - emptyBag) - -getTyDeclNames (TySynonym tycon _ _ src_loc) - = newGlobalName src_loc Nothing False{-not val-} tycon `thenRn` \ tycon_name -> - returnRn (RnSyn tycon_name, emptyBag, emptyBag) - ----------------- -getConFieldNames :: Maybe ExportFlag - -> Bag Name -> Bag Name - -> FiniteMap RdrName () - -> [RdrNameConDecl] - -> RnM_Info s ([Name], [Name]) - -getConFieldNames exp constrs fields have [] - = returnRn (bagToList constrs, bagToList fields) - -getConFieldNames exp constrs fields have (ConDecl con _ src_loc : rest) - = newGlobalName src_loc exp True{-val-} con `thenRn` \ con_name -> - getConFieldNames exp (constrs `snocBag` con_name) fields have rest - -getConFieldNames exp constrs fields have (ConOpDecl _ con _ src_loc : rest) - = newGlobalName src_loc exp True{-val-} con `thenRn` \ con_name -> - getConFieldNames exp (constrs `snocBag` con_name) fields have rest - -getConFieldNames exp constrs fields have (RecConDecl con fielddecls src_loc : rest) - = mapRn (addErrRn . dupFieldErr con src_loc) dups `thenRn_` - newGlobalName src_loc exp True{-val-} con `thenRn` \ con_name -> - mapRn (newGlobalName src_loc exp True{-val-}) new_fields `thenRn` \ field_names -> + -- If there's an error in loadInterface, (e.g. interface + -- file not found) we get lots of spurious errors from 'filterImports' let - all_constrs = constrs `snocBag` con_name - all_fields = fields `unionBags` listToBag field_names + imp_mod_name = unLoc loc_imp_mod_name + this_mod_name = moduleName this_mod + doc = ppr imp_mod_name <+> ptext SLIT("is directly imported") in - getConFieldNames exp all_constrs all_fields new_have rest - where - (uniq_fields, dups) = removeDups cmp (concat (map fst fielddecls)) - new_fields = filter (not . maybeToBool . lookupFM have) uniq_fields - new_have = addListToFM have (zip new_fields (repeat ())) - -------------- -getClassNames :: RdrNameClassDecl - -> RnM_Info s (RnName, Bag RnName) -- class and class ops - -getClassNames (ClassDecl _ cname _ sigs _ _ src_loc) - = newGlobalName src_loc Nothing False{-notval-} cname `thenRn` \ class_name -> - getClassOpNames (Just (nameExportFlag class_name)) - sigs `thenRn` \ op_names -> - returnRn (RnClass class_name op_names, - listToBag (map (\ n -> RnClassOp n class_name) op_names)) - ---------------- -getClassOpNames :: Maybe ExportFlag - -> [RdrNameSig] - -> RnM_Info s [Name] - -getClassOpNames exp [] = returnRn [] - -getClassOpNames exp (ClassOpSig op _ _ src_loc : sigs) - = newGlobalName src_loc exp True{-val-} op `thenRn` \ op_name -> - getClassOpNames exp sigs `thenRn` \ op_names -> - returnRn (op_name : op_names) -getClassOpNames exp (_ : sigs) - = getClassOpNames exp sigs -\end{code} + loadSrcInterface doc imp_mod_name want_boot `thenM` \ iface -> -********************************************************* -* * -\subsection{Bindings} -* * -********************************************************* + -- 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 ) -\begin{code} -getTopBindsNames :: RdrNameHsBinds - -> RnM_Info s (Bag RnName) - -getTopBindsNames binds = doBinds binds - -doBinds EmptyBinds = returnRn emptyBag -doBinds (SingleBind bind) = doBind bind -doBinds (BindWith bind sigs) = doBind bind -doBinds (ThenBinds binds1 binds2) - = andRn unionBags (doBinds binds1) (doBinds binds2) - -doBind EmptyBind = returnRn emptyBag -doBind (NonRecBind mbind) = doMBinds mbind -doBind (RecBind mbind) = doMBinds mbind - -doMBinds EmptyMonoBinds = returnRn emptyBag -doMBinds (PatMonoBind pat grhss_and_binds locn) = doPat locn pat -doMBinds (FunMonoBind p_name _ _ locn) = doName locn p_name -doMBinds (AndMonoBinds mbinds1 mbinds2) - = andRn unionBags (doMBinds mbinds1) (doMBinds mbinds2) - -doPats locn pats - = mapRn (doPat locn) pats `thenRn` \ pats_s -> - returnRn (unionManyBags pats_s) - -doPat locn WildPatIn = returnRn emptyBag -doPat locn (LitPatIn _) = returnRn emptyBag -doPat locn (LazyPatIn pat) = doPat locn pat -doPat locn (VarPatIn var) = doName locn var -doPat locn (NegPatIn pat) = doPat locn pat -doPat locn (ParPatIn pat) = doPat locn pat -doPat locn (ListPatIn pats) = doPats locn pats -doPat locn (TuplePatIn pats) = doPats locn pats -doPat locn (ConPatIn name pats) = doPats locn pats -doPat locn (ConOpPatIn p1 op p2) - = andRn unionBags (doPat locn p1) (doPat locn p2) -doPat locn (AsPatIn as_name pat) - = andRn unionBags (doName locn as_name) (doPat locn pat) -doPat locn (RecPatIn name fields) - = mapRn (doField locn) fields `thenRn` \ fields_s -> - returnRn (unionManyBags fields_s) - -doField locn (_, pat, _) = doPat locn pat - -doName locn rdr - = newGlobalName locn Nothing True{-val-} rdr `thenRn` \ name -> - returnRn (unitBag (RnName name)) -\end{code} - -********************************************************* -* * -\subsection{Creating a new global 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_` -\begin{code} -newGlobalName :: SrcLoc - -> Maybe ExportFlag - -> Bool{-True<=>value name,False<=>tycon/class-} - -> RdrName - -> RnM_Info s Name - -newGlobalName locn maybe_exp is_val_name (Unqual name) - = getExtraRn `thenRn` \ ((b_val_names,b_tc_names),b_keys,rec_exp_fn,rec_occ_fn) -> - getModuleRn `thenRn` \ mod -> - rnGetUnique `thenRn` \ u -> let - orig = OrigName mod name - - (uniq, is_toplev) - = case (lookupFM b_keys orig) of - Just (key,_) -> (key, True) - Nothing -> if not opt_CompilingGhcInternals then (u,True) else -- really here just to save gratuitous lookup - case (lookupFM (if is_val_name then b_val_names else b_tc_names) orig) of - Nothing -> (u, True) - Just xx -> (uniqueOf xx, False{-builtin!-}) - - exp = case maybe_exp of - Just flag -> flag - Nothing -> rec_exp_fn n - - n = if is_toplev - then mkTopLevName uniq orig locn exp (rec_occ_fn n) -- NB: two "n"s - else mkWiredInName uniq orig exp + 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 + -- 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. + + qual_mod_name = case as_mod of + Nothing -> imp_mod_name + Just another_name -> another_name + imp_spec = ImportSpec { is_mod = imp_mod_name, is_qual = qual_only, + is_loc = loc, is_as = qual_mod_name } in - returnRn n -newGlobalName locn maybe_exp is_val_name rdr@(Qual mod name) - | opt_CompilingGhcInternals - -- we are actually defining something that compiler knows about (e.g., Bool) + -- Get the total imports, and filter them according to the import list + exportsToAvails filtered_exports `thenM` \ total_avails -> + filterImports iface imp_spec + imp_details total_avails `thenM` \ (avail_env, gbl_env) -> - = getExtraRn `thenRn` \ ((b_val_names,b_tc_names),b_keys,rec_exp_fn,rec_occ_fn) -> let - orig = OrigName mod name - - (uniq, is_toplev) - = case (lookupFM b_keys orig) of - Just (key,_) -> (key, True) - Nothing -> case (lookupFM (if is_val_name then b_val_names else b_tc_names) orig) of - Nothing -> (pprPanic "newGlobalName:Qual:uniq:" (ppr PprDebug rdr), True) - Just xx -> (uniqueOf xx, False{-builtin!-}) - - exp = case maybe_exp of - Just flag -> flag - Nothing -> rec_exp_fn n - - n = if is_toplev - then mkTopLevName uniq orig locn exp (rec_occ_fn n) -- NB: two "n"s - else mkWiredInName uniq orig exp - in - returnRn n + -- 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]) + + -- 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. + 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 } - | otherwise - = addErrRn (qualNameErr "name in definition" (rdr, locn)) `thenRn_` - returnRn (pprPanic "newGlobalName:Qual:" (ppr PprDebug rdr)) + 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) + +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_nm (Avail n) = do { n' <- lookupOrig mod_nm n; + ; return (Avail n') } + do_avail mod_nm (AvailTC n ns) = do { n' <- lookupOrig mod_nm n + ; ns' <- mappM (lookup_sub n') ns + ; return (AvailTC n' ns') } + where + mod = mkPackageModule mod_nm -- Not necessarily right yet + lookup_sub parent occ = newGlobalBinder mod occ (Just parent) noSrcLoc + -- Hack alert! Notice the newGlobalBinder. 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. + -- Reason for all this: + -- Suppose module M exports type A.T, and constructor A.MkT + -- Then, we know that A.MkT is a subordinate name of A.T, + -- even though we aren't at the binding site of A.T + -- And it's important, because we may simply re-export A.T + -- without ever sucking in the declaration itself. + +warnRedundantSourceImport mod_name + = ptext SLIT("Unnecessary {- SOURCE -} in the import of module") + <+> quotes (ppr mod_name) \end{code} -********************************************************* -* * -\subsection{Imported names} -* * -********************************************************* -\begin{code} -type ImportNameInfo - = (GlobalNameInfo, - FiniteMap OrigName RnName, -- values imported so far - FiniteMap OrigName RnName, -- tycons/classes imported so far - Name -> (ExportFlag, [SrcLoc])) -- import flag and src locns; - -- NB: this last field is in a knot - -- and mustn't be tugged on! - -type RnM_IInfo s r = RnMonad ImportNameInfo s r - ------------------------------------------------------------------- -doImportDecls :: - IfaceCache - -> GlobalNameInfo -- builtin and knot name info - -> UniqSupply - -> [RdrNameImportDecl] -- import declarations - -> IO (Bag (RdrName,RnName), -- imported values in scope - Bag (RdrName,RnName), -- imported tycons/classes in scope - [Module], -- directly imported modules - Bag (Module,RnName), -- unqualified import from module - Bag RenamedFixityDecl, -- fixity info for imported names - Bag Error, - Bag Warning) - -doImportDecls iface_cache g_info us src_imps - = fixIO ( \ ~(_, _, _, _, _, _, rec_imp_stuff) -> - let - rec_imp_fm = addListToUFM_C add_stuff emptyUFM (bagToList rec_imp_stuff) - add_stuff (imp1,locns1) (imp2,locns2) = (lubExportFlag imp1 imp2, locns1 `unionBags` locns2) +%************************************************************************ +%* * + importsFromLocalDecls +%* * +%************************************************************************ - rec_imp_fn :: Name -> (ExportFlag, [SrcLoc]) - rec_imp_fn n = case lookupUFM rec_imp_fm n of - Nothing -> panic "RnNames:rec_imp_fn" - Just (flag, locns) -> (flag, bagToList locns) +From the top-level declarations of this module produce + * the lexical environment + * the ImportAvails +created by its bindings. + +Complain about duplicate bindings - i_info = (g_info, emptyFM, emptyFM, rec_imp_fn) - in - -- cache the imported modules - -- this ensures that all directly imported modules - -- will have their original name iface in scope - -- pprTrace "doImportDecls:" (ppCat (map ppPStr imp_mods)) $ - accumulate (map (cachedIface iface_cache False SLIT("doImportDecls")) imp_mods) >> +\begin{code} +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 + all_names :: [Name] -- All the defns; no dups eliminated + all_names = [name | avail <- avails, name <- availNames avail] - -- process the imports - doImports iface_cache i_info us all_imps + dups :: [[Name]] + (_, dups) = removeDups compare all_names + in + -- Check for duplicate definitions + -- The complaint will come out as "Multiple declarations of Foo.f" because + -- since 'f' is in the env twice, the unQualInScope used by the error-msg + -- printer returns False. It seems awkward to fix, unfortunately. + mappM_ (addErr . dupDeclErr) dups `thenM_` - ) >>= \ (vals, tcs, unquals, fixes, errs, warns, _) -> + doptM Opt_NoImplicitPrelude `thenM` \ implicit_prelude -> + let + mod_name = moduleName this_mod + prov = LocalDef mod_name + gbl_env = mkGlobalRdrEnv gres + gres = [ GRE { gre_name = name, gre_prov = prov} + | name <- all_names] + + -- 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. + -- 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. + + 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. [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} - return (vals, tcs, imp_mods, unquals, fixes, - imp_errs `unionBags` errs, - imp_warns `unionBags` warns) - where - all_imps = implicit_prel ++ src_imps --- all_imps = implicit_qprel ++ the_imps - explicit_prelude_imp - = not (null [ () | (ImportDecl mod qual _ _ _) <- src_imps, mod == pRELUDE ]) +%********************************************************* +%* * +\subsection{Getting binders out of a declaration} +%* * +%********************************************************* - implicit_prel | opt_NoImplicitPrelude = [] - | explicit_prelude_imp = [ImportDecl pRELUDE True Nothing Nothing prel_loc] - | otherwise = [ImportDecl pRELUDE False Nothing Nothing prel_loc] +@getLocalDeclBinders@ returns the names for an @HsDecl@. It's +used for source code. - prel_loc = mkBuiltinSrcLoc + *** See "THE NAMING STORY" in HsDecls **** - (uniq_imps, imp_dups) = removeDups cmp_mod all_imps - cmp_mod (ImportDecl m1 _ _ _ _) (ImportDecl m2 _ _ _ _) = cmpPString m1 m2 +\begin{code} +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. + + 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_simple rdr_name = newTopSrcBinder mod Nothing rdr_name `thenM` \ name -> + returnM (Avail name) + + val_hs_bndrs = collectGroupBinders val_decls + for_hs_bndrs = [nm | L _ (ForeignImport nm _ _ _) <- 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 (unLoc tc_decl) +\end{code} - qprel_imps = [ imp | imp@(ImportDecl mod True Nothing _ _) <- src_imps, - mod == pRELUDE ] - qual_mods = [ (qual_name mod as_mod, imp) | imp@(ImportDecl mod True as_mod _ _) <- src_imps ] - qual_name mod (Just as_mod) = as_mod - qual_name mod Nothing = mod +%************************************************************************ +%* * +\subsection{Filtering imports} +%* * +%************************************************************************ - (_, qual_dups) = removeDups cmp_qual qual_mods - bad_qual_dups = filter (not . all_same_mod) qual_dups +@filterImports@ takes the @ExportEnv@ telling what the imported module makes +available, and filters it through the import spec (if any). - cmp_qual (q1,_) (q2,_) = cmpPString q1 q2 - all_same_mod ((q,ImportDecl mod _ _ _ _):rest) - = all has_same_mod rest - where - has_same_mod (_,ImportDecl mod2 _ _ _ _) = mod == mod2 - - imp_mods = [ mod | ImportDecl mod _ _ _ _ <- uniq_imps ] - - imp_warns = listToBag (map dupImportWarn imp_dups) - `unionBags` - listToBag (map qualPreludeImportWarn qprel_imps) - - imp_errs = listToBag (map dupQualImportErr bad_qual_dups) - ------------------------ -doImports :: IfaceCache - -> ImportNameInfo - -> UniqSupply - -> [RdrNameImportDecl] -- import declarations - -> IO (Bag (RdrName,RnName), -- imported values in scope - Bag (RdrName,RnName), -- imported tycons/classes in scope - Bag (Module, RnName), -- unqualified import from module - Bag RenamedFixityDecl, -- fixity info for imported names - Bag Error, - Bag Warning, - Bag (RnName,(ExportFlag,Bag SrcLoc))) -- import flags and src locs - -doImports iface_cache i_info us [] - = return (emptyBag, emptyBag, emptyBag, emptyBag, emptyBag, emptyBag, emptyBag) - -doImports iface_cache i_info@(g_info,done_vals,done_tcs,rec_imp_fn) us (imp:imps) - = let - (us1, us2) = splitUniqSupply us - in - doImport iface_cache i_info us1 imp - >>= \ (vals1, tcs1, unquals1, fixes1, errs1, warns1, imps1) -> +\begin{code} +filterImports :: ModIface + -> ImportSpec -- The span for the entire import decl + -> Maybe (Bool, [Located (IE RdrName)]) -- Import spec; True => hiding + -> [AvailInfo] -- What's available + -> RnM (AvailEnv, -- What's imported + GlobalRdrEnv) -- ...in two forms + + -- Complains if import spec mentions things that the module doesn't export + -- Warns/informs if import spec contains duplicates. +mkGenericRdrEnv imp_spec avails + = mkGlobalRdrEnv [ GRE { gre_name = name, gre_prov = Imported [imp_spec] False } + | avail <- avails, name <- availNames avail ] + +filterImports iface imp_spec Nothing total_avails + = returnM (mkAvailEnv total_avails, mkGenericRdrEnv imp_spec total_avails) + +filterImports iface imp_spec (Just (want_hiding, import_items)) total_avails + = mapAndUnzipM (addLocM get_item) import_items `thenM` \ (avails, gres) -> let - ext_vals = foldl add_new_one done_vals (bagToList vals1) - ext_tcs = foldl add_new_one done_tcs (bagToList tcs1) + all_avails = foldr plusAvailEnv emptyAvailEnv avails + rdr_env = foldr plusGlobalRdrEnv emptyGlobalRdrEnv gres in - doImports iface_cache (g_info,ext_vals,ext_tcs,rec_imp_fn) us2 imps - >>= \ (vals2, tcs2, unquals2, fixes2, errs2, warns2, imps2) -> - return (vals1 `unionBags` vals2, - tcs1 `unionBags` tcs2, - unquals1 `unionBags` unquals2, - fixes1 `unionBags` fixes2, - errs1 `unionBags` errs2, - warns1 `unionBags` warns2, - imps1 `unionBags` imps2) - where - add_new_one :: FiniteMap OrigName RnName -- ones done so far - -> (dont_care, RnName) - -> FiniteMap OrigName RnName -- extended - - add_new_one fm (_, rn) - = let - orig = origName "add_new_one" rn - in - case (lookupFM fm orig) of - Just _ -> fm -- already there: no change - Nothing -> addToFM fm orig rn - ----------------------- -doImport :: IfaceCache - -> ImportNameInfo - -> UniqSupply - -> RdrNameImportDecl - -> IO (Bag (RdrName,RnName), -- values - Bag (RdrName,RnName), -- tycons/classes - Bag (Module,RnName), -- unqual imports - Bag RenamedFixityDecl, - Bag Error, - Bag Warning, - Bag (RnName,(ExportFlag,Bag SrcLoc))) -- import flags and src locs - -doImport iface_cache info us (ImportDecl mod qual maybe_as maybe_spec src_loc) - = --let - -- (b_vals, b_tcs, maybe_spec') - -- = (emptyBag, emptyBag, maybe_spec) - --in - --pprTrace "doImport:" (ppPStr mod) $ - cachedIface iface_cache False SLIT("doImport") mod >>= \ maybe_iface -> - return (maybe_iface, \ iface -> getOrigIEs iface maybe_spec) - >>= \ (maybe_iface, do_ies) -> - - case maybe_iface of - Failed err -> - return (emptyBag, emptyBag, emptyBag, emptyBag, - unitBag err, emptyBag, emptyBag) - Succeeded iface -> - let - (ies, chk_ies, get_errs) = do_ies iface - in - doOrigIEs iface_cache info mod src_loc us ies - >>= \ (ie_vals, ie_tcs, imp_flags, errs, warns) -> - accumulate (map (checkOrigIE iface_cache) chk_ies) - >>= \ chk_errs_warns -> - let - fold_ies = foldBag unionBags pair_occ emptyBag - - final_vals = {-OLD:mapBag fst_occ b_vals `unionBags`-} fold_ies ie_vals - final_tcs = {-OLD:mapBag fst_occ b_tcs `unionBags`-} fold_ies ie_tcs - final_vals_list = bagToList final_vals - in - accumulate (map (getFixityDecl iface_cache . snd) final_vals_list) - >>= \ fix_maybes_errs -> - let - (chk_errs, chk_warns) = unzip chk_errs_warns - (fix_maybes, fix_errs) = unzip fix_maybes_errs - - unquals = if qual{-ified import-} - then emptyBag - else mapBag pair_as (ie_vals `unionBags` ie_tcs) - - final_fixes = listToBag (catMaybes fix_maybes) - - final_errs = mapBag (\ err -> err mod src_loc) (unionManyBags (get_errs:chk_errs)) - `unionBags` errs `unionBags` unionManyBags fix_errs - final_warns = mapBag (\ warn -> warn mod src_loc) (unionManyBags chk_warns) - `unionBags` warns - imp_stuff = mapBag (\ (n,imp) -> (n,(imp,unitBag src_loc))) imp_flags - in - return (final_vals, final_tcs, unquals, final_fixes, - final_errs, final_warns, imp_stuff) + if not want_hiding then + returnM (all_avails, rdr_env) + else + let -- Hide stuff in all_avails + hidden = availsToNameSet (availEnvElts all_avails) + keep n = not (n `elemNameSet` hidden) + pruned_avails = pruneAvails keep total_avails + in + returnM (mkAvailEnv pruned_avails, mkGenericRdrEnv imp_spec pruned_avails) where - as_mod :: Module - as_mod = case maybe_as of {Nothing -> mod; Just as_this -> as_this} + import_fm :: OccEnv AvailInfo + import_fm = mkOccEnv [ (nameOccName name, avail) + | avail <- total_avails, + name <- availNames avail] + -- Even though availNames returns data constructors too, + -- they won't make any difference because naked entities like T + -- in an import list map to TcOccs, not VarOccs. + + bale_out item = addErr (badImportItemErr iface imp_spec item) `thenM_` + returnM (emptyAvailEnv, emptyGlobalRdrEnv) + + succeed_with :: Bool -> AvailInfo -> RnM (AvailEnv, GlobalRdrEnv) + succeed_with all_explicit avail + = do { loc <- getSrcSpanM + ; returnM (unitAvailEnv avail, + mkGlobalRdrEnv (map (mk_gre loc) (availNames avail))) } + where + mk_gre loc name = GRE { gre_name = name, + gre_prov = Imported [this_imp_spec loc] (explicit name) } + this_imp_spec loc = imp_spec { is_loc = loc } + explicit name = all_explicit || name == main_name + main_name = availName avail + + get_item :: IE RdrName -> RnM (AvailEnv, GlobalRdrEnv) + -- Empty result for a bad item. + -- Singleton result is typical case. + -- Can have two when we are hiding, and mention C which might be + -- both a class and a data constructor. + get_item item@(IEModuleContents _) + = bale_out item + + get_item item@(IEThingAll tc) + = 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 tc)) `thenM_` + succeed_with False avail + Just avail -> succeed_with False 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 (mkAvailEnv avails, emptyGlobalRdrEnv) + -- The GlobalRdrEnv result is irrelevant when hiding + where + data_n = setRdrNameSpace n srcDataName - mk_occ :: FAST_STRING -> RdrName - mk_occ str = if qual then Qual as_mod str else Unqual str + get_item item + = case check_item item of + Nothing -> bale_out item + Just avail -> succeed_with True avail - fst_occ :: (FAST_STRING, RnName) -> (RdrName, RnName) - fst_occ (str, rn) = (mk_occ str, rn) + check_item item + | isNothing maybe_in_import_avails || + isNothing maybe_filtered_avail + = Nothing - pair_occ :: RnName -> Bag (RdrName, RnName) - pair_occ rn - = let - str = getLocalName rn - qual_bag = unitBag (Qual as_mod str, rn) - in - if qual - then qual_bag - else qual_bag -- the qualified name is *also* visible - `snocBag` (Unqual str, rn) - - - pair_as :: RnName -> (Module, RnName) - pair_as rn = (as_mod, rn) - ------------------------------ -{- -getBuiltins :: ImportNameInfo - -> Module - -> Maybe (Bool, [RdrNameIE]) - -> (Bag (FAST_STRING, RnName), - Bag (FAST_STRING, RnName), - Maybe (Bool, [RdrNameIE]) -- return IEs that had no effect - ) - -getBuiltins _ modname maybe_spec --- | modname `notElem` modulesWithBuiltins - = (emptyBag, emptyBag, maybe_spec) - -getBuiltins (((b_val_names,b_tc_names),_,_,_),_,_,_) modname maybe_spec - = case maybe_spec of - Nothing -> (all_vals, all_tcs, Nothing) - - Just (True, ies) -> -- hiding does not work for builtin names - trace "NOTE: `import Prelude hiding ...' does not hide built-in names" $ - (all_vals, all_tcs, maybe_spec) - - Just (False, ies) -> let - (vals,tcs,ies_left) = do_builtin ies - in - (vals, tcs, Just (False, ies_left)) - where - all_vals = do_all_builtin (fmToList b_val_names) - all_tcs = do_all_builtin (fmToList b_tc_names) - - do_all_builtin [] = emptyBag - do_all_builtin (((OrigName mod str),rn):rest) - = --pprTrace "do_all_builtin:" (ppCat [ppPStr modname, ppPStr mod, ppPStr str]) $ - (if mod == modname then consBag (str, rn) else id) (do_all_builtin rest) - - do_builtin [] = (emptyBag,emptyBag,[]) - do_builtin (ie:ies) - = let - (str, orig) - = case (ie_name ie) of - Unqual s -> (s, OrigName modname s) - Qual m s -> pprTrace "do_builtin:surprising qual!" (ppCat [ppPStr m, ppPStr s]) $ - (s, OrigName modname s) - in - case (lookupFM b_tc_names orig) of -- NB: we favour the tycon/class FM... - Just rn -> case (ie,rn) of - (IEThingAbs _, WiredInTyCon tc) - -> (vals, (str, rn) `consBag` tcs, ies_left) - (IEThingAll _, WiredInTyCon tc) - -> (listToBag (map (\ id -> (getLocalName id, WiredInId id)) - (tyConDataCons tc)) - `unionBags` vals, - (str,rn) `consBag` tcs, ies_left) - (IEThingWith _ _, WiredInTyCon tc) -- No checking of With... - -> (listToBag (map (\ id -> (nameOf (origName "IEThingWith" id), WiredInId id)) - (tyConDataCons tc)) - `unionBags` vals, - (str,rn) `consBag` tcs, ies_left) - _ -> panic "importing builtin names (1)" - - Nothing -> - case (lookupFM b_val_names orig) of - Nothing -> (vals, tcs, ie:ies_left) - Just rn -> case (ie,rn) of - (IEVar _, WiredInId _) - -> ((str, rn) `consBag` vals, tcs, ies_left) - _ -> panic "importing builtin names (2)" + | otherwise + = Just filtered_avail + where - (vals, tcs, ies_left) = do_builtin ies --} - -------------------------- -getOrigIEs :: ParsedIface - -> Maybe (Bool, [RdrNameIE]) -- "hiding" or not, blah, blah, blah - -> ([IE OrigName], - [(IE OrigName, ExportFlag)], - Bag (Module -> SrcLoc -> Error)) + wanted_occ = rdrNameOcc (ieName item) + maybe_in_import_avails = lookupOccEnv import_fm wanted_occ -getOrigIEs (ParsedIface _ _ _ _ _ _ exps _ _ _ _ _ _) Nothing -- import all - = (map mkAllIE (eltsFM exps), [], emptyBag) + Just avail = maybe_in_import_avails + maybe_filtered_avail = filterAvail item avail + Just filtered_avail = maybe_filtered_avail +\end{code} -getOrigIEs (ParsedIface _ _ _ _ _ _ exps _ _ _ _ _ _) (Just (True, ies)) -- import hiding - = (map mkAllIE (eltsFM exps_left), found_ies, errs) +\begin{code} +filterAvail :: IE RdrName -- 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 - (found_ies, errs) = lookupIEs exps ies - exps_left = delListFromFM exps (map (getLocalName.ie_name.fst) found_ies) + 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} -getOrigIEs (ParsedIface _ _ _ _ _ _ exps _ _ _ _ _ _) (Just (False, ies)) -- import these - = (map fst found_ies, found_ies, errs) - where - (found_ies, errs) = lookupIEs exps ies - ------------------------------------------------- -mkAllIE :: (OrigName, ExportFlag) -> IE OrigName - -mkAllIE (orig,ExportAbs) - = --ASSERT(isLexCon (nameOf orig)) - -- the ASSERT is correct, but it is too easy to - -- trigger when writing .hi files by hand (e.g. - -- when hackily breaking a module loop) - IEThingAbs orig -mkAllIE (orig, ExportAll) - | isLexCon name_orig || isLexSpecialSym name_orig - = IEThingAll orig - | otherwise - = IEVar orig - where - name_orig = nameOf orig ------------- -lookupIEs :: ExportsMap - -> [RdrNameIE] - -> ([(IE OrigName, ExportFlag)], -- IEs we found, orig-ified - Bag (Module -> SrcLoc -> Error)) +%************************************************************************ +%* * +\subsection{Export list processing} +%* * +%************************************************************************ -lookupIEs exps ies - = foldr go ([], emptyBag) ies - where - go ie (already, errs) - = let - str = case (ie_name ie) of - Unqual s -> s - Qual m s -> s - in - case (lookupFM exps str) of - Nothing -> - (already, unknownImpSpecErr ie `consBag` errs) - Just (orig, flag) -> - ((orig_ie orig ie, flag) : already, - adderr_if (seen_ie orig already) (duplicateImpSpecErr ie) errs) - - orig_ie orig (IEVar n) = IEVar orig - orig_ie orig (IEThingAbs n) = IEThingAbs orig - orig_ie orig (IEThingAll n) = IEThingAll orig - orig_ie orig (IEThingWith n ns) = IEThingWith orig (map re_orig ns) - where - (OrigName mod _) = orig - re_orig (Unqual s) = OrigName mod s +Processing the export list. - seen_ie orig seen_ies = any (\ (ie,_) -> orig == ie_name ie) seen_ies +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). --------------------------------------------- -doOrigIEs iface_cache info mod src_loc us [] - = return (emptyBag,emptyBag,emptyBag,emptyBag,emptyBag) +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 + AvailEnv) -- The accumulated exported stuff, kept in an env + -- so we can common-up related AvailInfos +emptyExportAccum = ([], emptyOccEnv, emptyAvailEnv) + +type ExportOccMap = OccEnv (Name, IE RdrName) + -- Tracks what a particular exported OccName + -- in an export list refers to, and which item + -- it came from. It's illegal to export two distinct things + -- that have the same occurrence name + + +exportsFromAvail :: Bool -- False => no 'module M(..) where' header at all + -> Maybe [Located (IE RdrName)] -- 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 explicit_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 + | explicit_mod = exports + | ghci_mode == Interactive = Nothing + | otherwise = Just [noLoc (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_litem) emptyExportAccum + export_items `thenM` \ (_, _, export_avail_map) -> + returnM (nameEnvElts export_avail_map) -doOrigIEs iface_cache info mod src_loc us (ie:ies) - = let - (us1, us2) = splitUniqSupply us - in - doOrigIE iface_cache info mod src_loc us1 ie - >>= \ (vals1, tcs1, imps1, errs1, warns1) -> - doOrigIEs iface_cache info mod src_loc us2 ies - >>= \ (vals2, tcs2, imps2, errs2, warns2) -> - return (vals1 `unionBags` vals2, - tcs1 `unionBags` tcs2, - imps1 `unionBags` imps2, - errs1 `unionBags` errs2, - warns1 `unionBags` warns2) - ----------------------- -doOrigIE :: IfaceCache - -> ImportNameInfo - -> Module - -> SrcLoc - -> UniqSupply - -> IE OrigName - -> IO (Bag RnName, -- values - Bag RnName, -- tycons/classes - Bag (RnName,ExportFlag), -- import flags - Bag Error, - Bag Warning) - -doOrigIE iface_cache info mod src_loc us ie - = with_decl iface_cache (ie_name ie) - avoided_fn - (\ err -> (emptyBag, emptyBag, emptyBag, unitBag err, emptyBag)) - (\ decl -> case initRn True mod emptyRnEnv us - (setExtraRn info $ - pushSrcLocRn src_loc $ - getIfaceDeclNames ie decl) - of - ((vals, tcs, imps), errs, warns) -> (vals, tcs, imps, errs, warns)) where - avoided_fn Nothing -- the thing should be in the source - = (emptyBag, emptyBag, emptyBag, emptyBag, emptyBag) - avoided_fn (Just (Left rn@(WiredInId _))) -- a builtin value brought into scope - = (unitBag rn, emptyBag, emptyBag, emptyBag, emptyBag) - avoided_fn (Just (Right rn@(WiredInTyCon tc))) - -- a builtin tc brought into scope; we also must bring its - -- data constructors into scope - = --pprTrace "avoided:Right:" (ppr PprDebug rn) $ - (listToBag [WiredInId dc | dc <- tyConDataCons tc], unitBag rn, emptyBag, emptyBag, emptyBag) - -------------------------- -checkOrigIE :: IfaceCache - -> (IE OrigName, ExportFlag) - -> IO (Bag (Module -> SrcLoc -> Error), Bag (Module -> SrcLoc -> Warning)) - -checkOrigIE iface_cache (IEThingAll n, ExportAbs) - = with_decl iface_cache n - (\ _ -> (emptyBag, emptyBag)) - (\ err -> (unitBag (\ mod locn -> err), emptyBag)) - (\ decl -> case decl of - TypeSig _ _ _ -> (emptyBag, unitBag (allWhenSynImpSpecWarn n)) - other -> (unitBag (allWhenAbsImpSpecErr n), emptyBag)) - -checkOrigIE iface_cache (IEThingWith n ns, ExportAbs) - = return (unitBag (withWhenAbsImpSpecErr n), emptyBag) - -checkOrigIE iface_cache (IEThingWith n ns, ExportAll) - = with_decl iface_cache n - (\ _ -> (emptyBag, emptyBag)) - (\ err -> (unitBag (\ mod locn -> err), emptyBag)) - (\ decl -> case decl of - NewTypeSig _ con _ _ -> (check_with "constructors" [con] ns, emptyBag) - DataSig _ cons fields _ _ -> (check_with "constructors (and fields)" (cons++fields) ns, emptyBag) - ClassSig _ ops _ _ -> (check_with "class ops" ops ns, emptyBag)) + exports_from_litem :: ExportAccum -> Located (IE RdrName) -> RnM ExportAccum + exports_from_litem acc = addLocM (exports_from_item acc) + + exports_from_item :: ExportAccum -> IE RdrName -> RnM ExportAccum + exports_from_item acc@(mods, occs, avails) ie@(IEModuleContents mod) + | mod `elem` mods -- Duplicate export of M + = 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 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 + = 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 + 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 + addErr (exportItemErr ie) `thenM_` + returnM acc ; + + Just export_avail -> + + -- Phew! It's OK! Now to check the occurrence stuff! + checkForDodgyExport ie avail `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 - check_with str has origs - | sortLt (<) (map getLocalName has) == sortLt (<) (map nameOf origs) - = emptyBag - | otherwise - = unitBag (withImpSpecErr str n has origs) - -checkOrigIE iface_cache other - = return (emptyBag, emptyBag) - ------------------------ -with_decl :: IfaceCache - -> OrigName - -> (Maybe (Either RnName RnName) -> something) -- if avoided.. - -> (Error -> something) -- if an error... - -> (RdrIfaceDecl -> something) -- if OK... - -> IO something - -with_decl iface_cache n do_avoid do_err do_decl - = cachedDecl iface_cache (isLexCon n_name || isLexSpecialSym n_name) n >>= \ maybe_decl -> - case maybe_decl of - CachingAvoided info -> return (do_avoid info) - CachingFail err -> return (do_err err) - CachingHit decl -> return (do_decl decl) + 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) + +------------------------------- +checkForDodgyExport :: IE RdrName -> AvailInfo -> RnM () +checkForDodgyExport (IEThingAll tc) (AvailTC _ [n]) = addWarn (dodgyExportWarn tc) + -- This occurs when you import T(..), but + -- only export T abstractly. The single [n] + -- in the AvailTC is the type or class itself +checkForDodgyExport _ _ = return () + +------------------------------- +check_occs :: IE RdrName -> ExportOccMap -> AvailInfo -> RnM ExportOccMap +check_occs ie occs avail + = foldlM check occs (availNames avail) where - n_name = nameOf n - -------------- -getFixityDecl :: IfaceCache - -> RnName - -> IO (Maybe RenamedFixityDecl, Bag Error) - -getFixityDecl iface_cache rn - = let - (OrigName mod str) = origName "getFixityDecl" rn - - succeeded infx i = return (Just (infx rn i), emptyBag) - in - cachedIface iface_cache True str mod >>= \ maybe_iface -> - case maybe_iface of - Failed err -> - return (Nothing, unitBag err) - Succeeded (ParsedIface _ _ _ _ _ _ _ _ fixes _ _ _ _) -> - case lookupFM fixes str of - Nothing -> return (Nothing, emptyBag) - Just (InfixL _ i) -> succeeded InfixL i - Just (InfixR _ i) -> succeeded InfixR i - Just (InfixN _ i) -> succeeded InfixN i - -ie_name (IEVar n) = n -ie_name (IEThingAbs n) = n -ie_name (IEThingAll n) = n -ie_name (IEThingWith n _) = n - -adderr_if True err errs = err `consBag` errs -adderr_if False err errs = errs + check occs name + = case lookupOccEnv occs name_occ of + Nothing -> returnM (extendOccEnv occs name_occ (name, 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 \end{code} -********************************************************* -* * -\subsection{Actually creating the imported names} -* * -********************************************************* +%********************************************************* +%* * + Deprecations +%* * +%********************************************************* \begin{code} -getIfaceDeclNames :: IE OrigName -> RdrIfaceDecl - -> RnM_IInfo s (Bag RnName, -- values - Bag RnName, -- tycons/classes - Bag (RnName,ExportFlag)) -- import flags - -getIfaceDeclNames ie (ValSig val src_loc _) - = newImportedName False src_loc Nothing Nothing val `thenRn` \ val_name -> - returnRn (unitBag (RnName val_name), - emptyBag, - unitBag (RnName val_name, ExportAll)) - -getIfaceDeclNames ie (TypeSig tycon src_loc _) - = newImportedName True src_loc Nothing Nothing tycon `thenRn` \ tycon_name -> - returnRn (emptyBag, - unitBag (RnSyn tycon_name), - unitBag (RnSyn tycon_name, ExportAll)) - -getIfaceDeclNames ie (NewTypeSig tycon con src_loc _) - = newImportedName True src_loc Nothing Nothing tycon `thenRn` \ tycon_name -> - newImportedName False src_loc (Just (nameExportFlag tycon_name)) - (Just (nameImportFlag tycon_name)) - con `thenRn` \ con_name -> - returnRn (if imp_all (imp_flag ie) then - unitBag (RnConstr con_name tycon_name) - else - emptyBag, - unitBag (RnData tycon_name [con_name] []), - unitBag (RnData tycon_name [con_name] [], imp_flag ie)) - -getIfaceDeclNames ie (DataSig tycon cons fields src_loc _) - = newImportedName True src_loc Nothing Nothing tycon `thenRn` \ tycon_name -> - let - map_me = mapRn (newImportedName False src_loc - (Just (nameExportFlag tycon_name)) - (Just (nameImportFlag tycon_name))) - in - map_me cons `thenRn` \ con_names -> - map_me fields `thenRn` \ field_names -> - let - rn_tycon = RnData tycon_name con_names field_names - rn_constrs = [ RnConstr name tycon_name | name <- con_names ] - rn_fields = [ RnField name tycon_name | name <- field_names ] - in - returnRn (if imp_all (imp_flag ie) then - listToBag rn_constrs `unionBags` listToBag rn_fields - else - emptyBag, - unitBag rn_tycon, - unitBag (rn_tycon, imp_flag ie)) - -getIfaceDeclNames ie (ClassSig cls ops src_loc _) - = newImportedName True src_loc Nothing Nothing cls `thenRn` \ cls_name -> - mapRn (newImportedName False src_loc (Just (nameExportFlag cls_name)) - (Just (nameImportFlag cls_name))) - ops `thenRn` \ op_names -> - returnRn (if imp_all (imp_flag ie) then - listToBag (map (\ n -> RnClassOp n cls_name) op_names) - else - emptyBag, - unitBag (RnClass cls_name op_names), - unitBag (RnClass cls_name op_names, imp_flag ie)) - - -imp_all ExportAll = True -imp_all _ = False - -imp_flag (IEThingAbs _) = ExportAbs -imp_flag (IEThingAll _) = ExportAll -imp_flag (IEThingWith _ _) = ExportAll +reportDeprecations :: TcGblEnv -> RnM () +reportDeprecations tcg_env + = ifOptM Opt_WarnDeprecations $ + do { hpt <- getHpt + ; eps <- getEps + ; mapM_ (check hpt (eps_PIT eps)) all_gres } + where + used_names = findUses (tcg_dus tcg_env) emptyNameSet + all_gres = globalRdrEnvElts (tcg_rdr_env tcg_env) + + check hpt pit (GRE {gre_name = name, gre_prov = Imported (imp_spec:_) _}) + | name `elemNameSet` used_names + , Just deprec_txt <- lookupDeprec hpt pit name + = addSrcSpan (is_loc imp_spec) $ + addWarn (sep [ptext SLIT("Deprecated use of") <+> + text (occNameFlavour (nameOccName name)) <+> + quotes (ppr name), + (parens imp_msg), + (ppr deprec_txt) ]) + where + name_mod = nameModuleName name + imp_mod = is_mod imp_spec + imp_msg = ptext SLIT("imported from") <+> ppr imp_mod <> extra + extra | imp_mod == name_mod = empty + | otherwise = ptext SLIT(", but defined in") <+> ppr name_mod + + check hpt pit ok_gre = returnM () -- Local, or not used, or not deprectated + -- The Imported pattern-match: 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 + -- the defn of a non-deprecated thing, when changing a module's + -- interface + +lookupDeprec :: HomePackageTable -> PackageIfaceTable + -> Name -> Maybe DeprecTxt +lookupDeprec hpt pit n + = case lookupIface hpt pit (nameModule n) of + Just iface -> mi_dep_fn iface n `seqMaybe` -- Bleat if the thing, *or + mi_dep_fn iface (nameParent n) -- its parent*, is deprec'd + Nothing -> pprPanic "lookupDeprec" (ppr n) + -- By now all the interfaces should have been loaded + +gre_is_used :: NameSet -> GlobalRdrElt -> Bool +gre_is_used used_names gre = gre_name gre `elemNameSet` used_names \end{code} -********************************************************* -* * -\subsection{Creating a new imported name} -* * -********************************************************* - -\begin{code} -newImportedName :: Bool -- True => tycon or class - -> SrcLoc - -> Maybe ExportFlag -- maybe export flag - -> Maybe ExportFlag -- maybe import flag - -> RdrName -- orig name - -> RnM_IInfo s Name - -newImportedName tycon_or_class locn maybe_exp maybe_imp rdr - = let - orig = qualToOrigName rdr - in - getExtraRn `thenRn` \ ((_,b_keys,rec_exp_fn,rec_occ_fn),done_vals,done_tcs,rec_imp_fn) -> - case ((if tycon_or_class - then lookupFM done_tcs - else lookupFM done_vals) orig) of - - Just rn -> returnRn (getName rn) - Nothing -> - rnGetUnique `thenRn` \ u -> - let - uniq = case lookupFM b_keys orig of - Nothing -> u - Just (key,_) -> key - - exp = case maybe_exp of - Just xx -> xx - Nothing -> rec_exp_fn n - - imp = case maybe_imp of - Just xx -> xx - Nothing -> imp_flag - - (imp_flag, imp_locs) = rec_imp_fn n - - n = mkImportedName uniq orig imp locn imp_locs exp (rec_occ_fn n) -- NB: two "n"s - in - returnRn n -\end{code} +%********************************************************* +%* * + Unused names +%* * +%********************************************************* \begin{code} -globalDupNamesErr rdr rns sty - = ppAboves (message : map pp_dup rns) +reportUnusedNames :: TcGblEnv -> RnM () +reportUnusedNames gbl_env + = do { warnUnusedTopBinds unused_locals + ; warnUnusedModules unused_imp_mods + ; warnUnusedImports unused_imports + ; warnDuplicateImports dup_imps + ; printMinimalImports minimal_imports } where - message = ppBesides [ppStr "multiple declarations of `", pprNonSym sty rdr, ppStr "'"] - - pp_dup rn = addShortErrLocLine (get_loc rn) (\ sty -> - ppCat [pp_descrip rn, pprNonSym sty rn]) sty - - get_loc rn = case getImpLocs rn of - [] -> getSrcLoc rn - locs -> head locs - - pp_descrip (RnName _) = ppStr "as a value:" - pp_descrip (RnSyn _) = ppStr "as a type synonym:" - pp_descrip (RnData _ _ _) = ppStr "as a data type:" - pp_descrip (RnConstr _ _) = ppStr "as a data constructor:" - pp_descrip (RnField _ _) = ppStr "as a record field:" - pp_descrip (RnClass _ _) = ppStr "as a class:" - pp_descrip (RnClassOp _ _) = ppStr "as a class method:" - pp_descrip _ = ppNil - -dupImportWarn (ImportDecl m1 _ _ _ locn1 : dup_imps) sty - = ppAboves (item1 : map dup_item dup_imps) + 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 + defined_names :: [GlobalRdrElt] + defined_names = globalRdrEnvElts (tcg_rdr_env gbl_env) + + -- Note that defined_and_used, defined_but_not_used + -- are both [GRE]; that's why we need defined_and_used + -- rather than just all_used_names + defined_and_used, defined_but_not_used :: [GlobalRdrElt] + (defined_and_used, defined_but_not_used) + = partition (gre_is_used all_used_names) defined_names + + -- Find the duplicate imports + dup_imps = filter is_dup defined_and_used + is_dup (GRE {gre_prov = Imported imp_spec True}) = not (isSingleton imp_spec) + is_dup other = False + + -- 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 + unused_locals :: [GlobalRdrElt] + unused_locals = filter is_unused_local defined_but_not_used + is_unused_local :: GlobalRdrElt -> Bool + is_unused_local gre = isLocalGRE gre && isExternalName (gre_name gre) + + unused_imports :: [GlobalRdrElt] + unused_imports = filter unused_imp defined_but_not_used + unused_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 + unused_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_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 (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 + + 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_imports1 + -- [Note: not 'minimal_imports', because that includes directly-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, + not (hasEmptyImpList m)] + -- hasEmptyImpList arranges not to complain about + -- import M (), which is an idiom for importing + -- instance declarations + + module_unused :: ModuleName -> Bool + module_unused mod = mod `elem` unused_imp_mods + +--------------------- +warnDuplicateImports :: [GlobalRdrElt] -> RnM () +warnDuplicateImports gres + = ifOptM Opt_WarnUnusedImports (mapM_ warn gres) where - item1 = addShortWarnLocLine locn1 (\ sty -> - ppCat [ppStr "multiple imports from module", ppPStr m1]) sty + warn (GRE { gre_name = name, gre_prov = Imported imps _ }) + = addWarn ((quotes (ppr name) <+> ptext SLIT("is imported more than once:")) + $$ nest 2 (vcat (map ppr imps))) + + +-- ToDo: deal with original imports with 'qualified' and 'as M' clauses +printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports + -> RnM () +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 -> 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. + to_ie (Avail n) = returnM (IEVar n) + to_ie (AvailTC n [m]) = ASSERT( n==m ) + returnM (IEThingAbs n) + to_ie (AvailTC n ns) + = loadSrcInterface doc n_mod False `thenM` \ iface -> + case [xs | (m,as) <- mi_exports iface, + m == n_mod, + AvailTC x xs <- as, + 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 + 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} - dup_item (ImportDecl m _ _ _ locn) - = addShortWarnLocLine locn (\ sty -> - ppCat [ppStr "here was another import from module", ppPStr m]) sty -qualPreludeImportWarn (ImportDecl m _ _ _ locn) - = addShortWarnLocLine locn (\ sty -> - ppCat [ppStr "qualified import of prelude module", ppPStr m]) +%************************************************************************ +%* * +\subsection{Errors} +%* * +%************************************************************************ -dupQualImportErr ((q1,ImportDecl _ _ _ _ locn1):dup_quals) sty - = ppAboves (item1 : map dup_item dup_quals) +\begin{code} +badImportItemErr iface imp_spec ie + = sep [ptext SLIT("Module"), quotes (ppr (is_mod imp_spec)), source_import, + ptext SLIT("does not export"), quotes (ppr ie)] + where + source_import | mi_boot iface = ptext SLIT("(hi-boot interface)") + | otherwise = empty + +dodgyImportWarn item = dodgyMsg (ptext SLIT("import")) item +dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) item + +dodgyMsg kind tc + = sep [ ptext SLIT("The") <+> kind <+> ptext SLIT("item") <+> quotes (ppr (IEThingAll tc)), + 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 (ppr mod)] + +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 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), + nest 4 (vcat (map ppr sorted_locs))] where - item1 = addShortErrLocLine locn1 (\ sty -> - ppCat [ppStr "multiple imports (from different modules) with same qualified name", ppPStr q1]) sty - - dup_item (q,ImportDecl _ _ _ _ locn) - = addShortErrLocLine locn (\ sty -> - ppCat [ppStr "here was another import with qualified name", ppPStr q]) sty - -unknownImpSpecErr ie imp_mod locn - = addShortErrLocLine locn (\ sty -> - ppBesides [ppStr "module ", ppPStr imp_mod, ppStr " does not export `", ppr sty (ie_name ie), ppStr "'"]) - -duplicateImpSpecErr ie imp_mod locn - = addShortErrLocLine locn (\ sty -> - ppBesides [ppStr "`", ppr sty (ie_name ie), ppStr "' already seen in import list"]) - -allWhenSynImpSpecWarn n imp_mod locn - = addShortWarnLocLine locn (\ sty -> - ppBesides [ppStr "type synonym `", ppr sty n, ppStr "' should not be imported with (..)"]) - -allWhenAbsImpSpecErr n imp_mod locn - = addShortErrLocLine locn (\ sty -> - ppBesides [ppStr "module ", ppPStr imp_mod, ppStr " only exports `", ppr sty n, ppStr "' abstractly"]) - -withWhenAbsImpSpecErr n imp_mod locn - = addShortErrLocLine locn (\ sty -> - ppBesides [ppStr "module ", ppPStr imp_mod, ppStr " only exports `", ppr sty n, ppStr "' abstractly"]) - -withImpSpecErr str n has ns imp_mod locn - = addErrLoc locn "" (\ sty -> - ppAboves [ ppBesides [ppStr "inconsistent list of", ppStr str, ppStr "in import list for `", ppr sty n, ppStr "'"], - ppCat [ppStr " expected:", ppInterleave ppComma (map (ppr sty) has)], - ppCat [ppStr " found: ", ppInterleave ppComma (map (ppr sty) ns)] ]) - -dupFieldErr con locn (dup:rest) - = addShortErrLocLine locn (\ sty -> - ppBesides [ppStr "record field `", ppr sty dup, ppStr "declared multiple times in `", ppr sty con, ppStr "'"]) + 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), + ptext SLIT("is exported by"), quotes (ppr ie1), + ptext SLIT("and"), quotes (ppr ie2)] + +dupModuleExport mod + = hsep [ptext SLIT("Duplicate"), + quotes (ptext SLIT("Module") <+> ppr mod), + ptext SLIT("in export list")] + +moduleDeprec mod txt + = sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"), + nest 4 (ppr txt) ] \end{code}