X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnNames.lhs;h=2cc62f8afe31095acdda0724e6905cb165d7d0ea;hb=4d57994585c858a7be242c8db23a3e40834dfc72;hp=8a8cc321e79dd6d77e9d9f0e4a096515143bc1c8;hpb=853e20a3eb86137cdb8accf69c6caa9db83a3d34;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnNames.lhs b/ghc/compiler/rename/RnNames.lhs index 8a8cc321..2cc62f8 100644 --- a/ghc/compiler/rename/RnNames.lhs +++ b/ghc/compiler/rename/RnNames.lhs @@ -6,8 +6,9 @@ \begin{code} module RnNames ( rnImports, importsFromLocalDecls, + getLocalDeclBinders, extendRdrEnvRn, reportUnusedNames, reportDeprecations, - mkModDeps, exportsToAvails, exportsFromAvail + mkModDeps, exportsFromAvail ) where #include "HsVersions.h" @@ -18,7 +19,7 @@ import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl, Sig(..), collectGroupBinders, tyClDeclNames ) import RnEnv -import IfaceEnv ( lookupAvail ) +import IfaceEnv ( ifaceExportNames ) import LoadIface ( loadSrcInterface ) import TcRnMonad @@ -34,8 +35,8 @@ import NameEnv import OccName ( srcDataName, isTcOcc, occNameFlavour, OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv, extendOccEnv ) import HscTypes ( GenAvailInfo(..), AvailInfo, - IfaceExport, HomePackageTable, PackageIfaceTable, - availNames, unQualInScope, + HomePackageTable, PackageIfaceTable, + unQualInScope, Deprecs(..), ModIface(..), Dependencies(..), lookupIface, ExternalPackageState(..) ) @@ -43,16 +44,16 @@ import Packages ( PackageIdH(..) ) import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..), emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts, - unQualOK, lookupGRE_Name, + extendGlobalRdrEnv, lookupGlobalRdrEnv, unQualOK, lookupGRE_Name, Provenance(..), ImportSpec(..), isLocalGRE, pprNameProvenance ) import Outputable import Maybes ( isNothing, catMaybes, mapCatMaybes, seqMaybe, orElse ) import SrcLoc ( Located(..), mkGeneralSrcSpan, - unLoc, noLoc, srcLocSpan, combineSrcSpans, SrcSpan ) + unLoc, noLoc, srcLocSpan, SrcSpan ) import BasicTypes ( DeprecTxt ) -import ListSetOps ( removeDups ) -import Util ( sortLe, notNull, isSingleton ) +import DriverPhases ( isHsBoot ) +import Util ( notNull ) import List ( partition ) import IO ( openFile, IOMode(..) ) \end{code} @@ -180,10 +181,10 @@ importsFromImportDecl this_mod 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 } + is_loc = loc, is_as = qual_mod_name, is_explicit = False } in -- Get the total imports, and filter them according to the import list - exportsToAvails filtered_exports `thenM` \ total_avails -> + ifaceExportNames filtered_exports `thenM` \ total_avails -> filterImports iface imp_spec imp_details total_avails `thenM` \ (avail_env, gbl_env) -> @@ -246,14 +247,6 @@ importsFromImportDecl this_mod returnM (gbl_env, imports) -exportsToAvails :: [IfaceExport] -> TcRnIf gbl lcl NameSet -exportsToAvails exports - = foldlM do_one emptyNameSet exports - where - do_one acc (mod, exports) = foldlM (do_avail mod) acc exports - do_avail mod acc avail = do { ns <- lookupAvail mod avail - ; return (addListToNameSet acc ns) } - warnRedundantSourceImport mod_name = ptext SLIT("Unnecessary {- SOURCE -} in the import of module") <+> quotes (ppr mod_name) @@ -274,32 +267,14 @@ created by its bindings. Complain about duplicate bindings \begin{code} -importsFromLocalDecls :: HsGroup RdrName - -> RnM (GlobalRdrEnv, ImportAvails) +importsFromLocalDecls :: HsGroup RdrName -> RnM TcGblEnv 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] + = do { gbl_env <- getGblEnv - 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_ addDupDeclErr dups `thenM_` - - doptM Opt_ImplicitPrelude `thenM` \ implicit_prelude -> - let - prov = LocalDef this_mod - gbl_env = mkGlobalRdrEnv gres - gres = [ GRE { gre_name = name, gre_prov = prov} - | name <- all_names] + ; names <- getLocalDeclBinders gbl_env group + ; implicit_prelude <- doptM Opt_ImplicitPrelude + ; let { -- 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 @@ -318,24 +293,42 @@ importsFromLocalDecls group -- 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. - filtered_names - | implicit_prelude = all_names - | otherwise = filter (not . isBuiltInSyntax) all_names + filtered_names + | implicit_prelude = names + | otherwise = filter (not . isBuiltInSyntax) names ; - imports = emptyImportAvails { - imp_env = unitModuleEnv this_mod $ + ; this_mod = tcg_mod gbl_env + ; imports = emptyImportAvails { + imp_env = unitModuleEnv this_mod $ mkNameSet filtered_names - } - in - returnM (gbl_env, imports) -\end{code} + } + } + ; rdr_env' <- extendRdrEnvRn this_mod (tcg_rdr_env gbl_env) names -%********************************************************* -%* * -\subsection{Getting binders out of a declaration} -%* * -%********************************************************* + ; returnM (gbl_env { tcg_rdr_env = rdr_env', + tcg_imports = imports `plusImportAvails` tcg_imports gbl_env }) + } + +extendRdrEnvRn :: Module -> GlobalRdrEnv -> [Name] -> RnM GlobalRdrEnv +-- Add the new locally-bound names one by one, checking for duplicates as +-- we do so. Remember that in Template Haskell the duplicates +-- might *already be* in the GlobalRdrEnv from higher up the module +extendRdrEnvRn mod rdr_env names + = foldlM add_local rdr_env names + where + add_local rdr_env name + | gres <- lookupGlobalRdrEnv rdr_env (nameOccName name) + , (dup_gre:_) <- filter isLocalGRE gres -- Check for existing *local* defns + = do { addDupDeclErr (gre_name dup_gre) name + ; return rdr_env } + | otherwise + = return (extendGlobalRdrEnv rdr_env new_gre) + where + new_gre = GRE {gre_name = name, gre_prov = prov} + + prov = LocalDef mod +\end{code} @getLocalDeclBinders@ returns the names for an @HsDecl@. It's used for source code. @@ -343,27 +336,21 @@ used for source code. *** See "THE NAMING STORY" in HsDecls **** \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 -> - +getLocalDeclBinders :: TcGblEnv -> HsGroup RdrName -> RnM [Name] +getLocalDeclBinders gbl_env (HsGroup {hs_valds = val_decls, + hs_tyclds = tycl_decls, + hs_fords = foreign_decls }) + = do { tc_names_s <- mappM new_tc tycl_decls + ; val_names <- mappM new_simple val_bndrs + ; return (foldr (++) val_names tc_names_s) } + where + mod = tcg_mod gbl_env + is_hs_boot = isHsBoot (tcg_src gbl_env) ; + val_bndrs | is_hs_boot = sig_hs_bndrs + | otherwise = for_hs_bndrs ++ val_hs_bndrs -- In a hs-boot file, the value binders come from the -- *signatures*, and there should be no foreign binders - tcIsHsBoot `thenM` \ is_hs_boot -> - let val_bndrs | is_hs_boot = sig_hs_bndrs - | otherwise = for_hs_bndrs ++ val_hs_bndrs - in - mappM new_simple val_bndrs `thenM` \ names -> - returnM (tc_avails ++ map Avail names) - where new_simple rdr_name = newTopSrcBinder mod Nothing rdr_name sig_hs_bndrs = [nm | HsBindGroup _ lsigs _ <- val_decls, @@ -372,9 +359,9 @@ getLocalDeclBinders mod (HsGroup {hs_valds = 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)) + = do { main_name <- newTopSrcBinder mod Nothing main_rdr + ; sub_names <- mappM (newTopSrcBinder mod (Just main_name)) sub_rdrs + ; return (main_name : sub_names) } where (main_rdr : sub_rdrs) = tyClDeclNames (unLoc tc_decl) \end{code} @@ -401,7 +388,7 @@ filterImports :: ModIface -- Warns/informs if import spec contains duplicates. mkGenericRdrEnv imp_spec names - = mkGlobalRdrEnv [ GRE { gre_name = name, gre_prov = Imported [imp_spec] False } + = mkGlobalRdrEnv [ GRE { gre_name = name, gre_prov = Imported [imp_spec] } | name <- nameSetToList names ] filterImports iface imp_spec Nothing all_names @@ -441,9 +428,10 @@ filterImports iface imp_spec (Just (want_hiding, import_items)) all_names ; returnM (map (mk_gre loc) names) } 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 || isNothing (nameParent_maybe name) + gre_prov = Imported [imp_spec'] } + where + imp_spec' = imp_spec { is_loc = loc, is_explicit = explicit } + explicit = all_explicit || isNothing (nameParent_maybe name) get_item :: IE RdrName -> RnM [GlobalRdrElt] -- Empty result for a bad item. @@ -614,6 +602,7 @@ filterAvail (IEThingWith _ rdrs) n subs where env = mkOccEnv [(nameOccName s, s) | s <- subNames subs n] mb_names = map (lookupOccEnv env . rdrNameOcc) rdrs +filterAvail (IEModuleContents _) _ _ = panic "filterAvail" subNames :: NameEnv [Name] -> Name -> [Name] subNames env n = lookupNameEnv env n `orElse` [] @@ -685,7 +674,7 @@ reportDeprecations tcg_env 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:_) _}) + check hpt pit (GRE {gre_name = name, gre_prov = Imported (imp_spec:_)}) | name `elemNameSet` used_names , Just deprec_txt <- lookupDeprec hpt pit name = setSrcSpan (is_loc imp_spec) $ @@ -741,7 +730,7 @@ reportUnusedNames export_decls gbl_env = do { warnUnusedTopBinds unused_locals ; warnUnusedModules unused_imp_mods ; warnUnusedImports unused_imports - ; warnDuplicateImports dup_imps + ; warnDuplicateImports defined_and_used ; printMinimalImports minimal_imports } where used_names, all_used_names :: NameSet @@ -762,11 +751,6 @@ reportUnusedNames export_decls gbl_env (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 @@ -778,8 +762,9 @@ reportUnusedNames export_decls gbl_env unused_imports :: [GlobalRdrElt] unused_imports = filter unused_imp defined_but_not_used - unused_imp (GRE {gre_prov = Imported imp_specs True}) + unused_imp (GRE {gre_prov = Imported imp_specs}) = not (all (module_unused . is_mod) imp_specs) + && any is_explicit imp_specs -- Don't complain about unused imports if we've already said the -- entire import is unused unused_imp other = False @@ -811,7 +796,7 @@ reportUnusedNames export_decls gbl_env -- 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 + 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 @@ -876,13 +861,65 @@ reportUnusedNames export_decls gbl_env --------------------- warnDuplicateImports :: [GlobalRdrElt] -> RnM () +-- Given the GREs for names that are used, figure out which imports +-- could be omitted without changing the top-level environment. +-- +-- NB: Given import Foo( T ) +-- import qualified Foo +-- we do not report a duplicate import, even though Foo.T is brought +-- into scope by both, because there's nothing you can *omit* without +-- changing the top-level environment. So we complain only if it's +-- explicitly named in both imports or neither. +-- +-- Furthermore, we complain about Foo.T only if +-- there is no complaint about (unqualified) T + warnDuplicateImports gres - = ifOptM Opt_WarnUnusedImports (mapM_ warn gres) + = ifOptM Opt_WarnUnusedImports $ + sequenceM_ [ warn name pr + -- The 'head' picks the first offending group + -- for this particular name + | GRE { gre_name = name, gre_prov = Imported imps } <- gres + , pr <- redundants imps ] where - 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))) - + warn name (red_imp, cov_imp) + = addWarnAt (is_loc red_imp) + (vcat [ptext SLIT("Redundant import of:") <+> quotes pp_name, + ptext SLIT("It is also") <+> ppr cov_imp]) + where + pp_name | is_qual red_imp = ppr (is_as red_imp) <> dot <> ppr occ + | otherwise = ppr occ + occ = nameOccName name + + redundants :: [ImportSpec] -> [(ImportSpec,ImportSpec)] + -- The returned pair is (redundant-import, covering-import) + redundants imps + = [ (red_imp, cov_imp) + | red_imp <- imps + , cov_imp <- take 1 (filter (covers red_imp) imps) ] + + -- "red_imp" is a putative redundant import + -- "cov_imp" potentially covers it + -- This test decides + covers red_imp cov_imp + | red_loc == cov_loc + = False -- Ignore diagonal elements + | not (is_as red_imp == is_as cov_imp) + = False -- They bring into scope different qualified names + | not (is_qual red_imp) && is_qual cov_imp + = False -- Covering one doesn't bring unqualified name into scope + | is_explicit red_imp + = not cov_explicit -- Redundant one is explicit and covering one isn't + || red_later -- Both are explicit; tie-break using red_later + | otherwise + = not cov_explicit -- Neither import is explicit + && (is_mod red_imp == is_mod cov_imp) -- They import the same module + && red_later -- Tie-break + where + cov_explicit = is_explicit cov_imp + red_loc = is_loc red_imp + cov_loc = is_loc cov_imp + red_later = red_loc > cov_loc -- ToDo: deal with original imports with 'qualified' and 'as M' clauses printMinimalImports :: FiniteMap Module AvailEnv -- Minimal imports @@ -979,16 +1016,13 @@ exportClashErr global_env name1 name2 ie1 ie2 (gre:_) -> gre [] -> pprPanic "exportClashErr" (ppr name) -addDupDeclErr :: [Name] -> TcRn () -addDupDeclErr names - = addErrAt big_loc $ +addDupDeclErr :: Name -> Name -> TcRn () +addDupDeclErr name1 name2 + = addErrAt (srcLocSpan loc2) $ vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr name1), - ptext SLIT("Declared at:") <+> vcat (map ppr sorted_locs)] + ptext SLIT("Declared at:") <+> vcat [ppr (nameSrcLoc name1), ppr loc2]] where - locs = map nameSrcLoc names - big_loc = foldr1 combineSrcSpans (map srcLocSpan locs) - name1 = head names - sorted_locs = sortLe (<=) (sortLe (<=) locs) + loc2 = nameSrcLoc name2 dupExportWarn occ_name ie1 ie2 = hsep [quotes (ppr occ_name),