X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Frename%2FRnNames.lhs;h=05cfa96f3555c81d955fc3581c57a9be4dbad691;hb=8b08c15b8ace5a76e341939081fbb6ad2736ddd1;hp=d61133b2b63fa73827629b79bb49fc6b4632bff4;hpb=b709009c523c281824005e6c0158a8e136d73931;p=ghc-hetmet.git diff --git a/compiler/rename/RnNames.lhs b/compiler/rename/RnNames.lhs index d61133b..05cfa96 100644 --- a/compiler/rename/RnNames.lhs +++ b/compiler/rename/RnNames.lhs @@ -30,28 +30,12 @@ import Module import Name import NameEnv import NameSet -import OccName ( srcDataName, pprNonVarNameSpace, - occNameSpace, - OccEnv, mkOccEnv, mkOccEnv_C, lookupOccEnv, - emptyOccEnv, extendOccEnv ) -import HscTypes ( GenAvailInfo(..), AvailInfo, availNames, availName, - HomePackageTable, PackageIfaceTable, - mkPrintUnqualified, availsToNameSet, - Deprecs(..), ModIface(..), Dependencies(..), - lookupIfaceByModule, ExternalPackageState(..) - ) -import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, Parent(..), - GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..), - emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts, - extendGlobalRdrEnv, lookupGlobalRdrEnv, - lookupGRE_RdrName, lookupGRE_Name, - Provenance(..), ImportSpec(..), ImpDeclSpec(..), ImpItemSpec(..), - importSpecLoc, importSpecModule, isLocalGRE, pprNameProvenance, - unQualSpecOK, qualSpecOK ) +import OccName +import HscTypes +import RdrName import Outputable import Maybes -import SrcLoc ( Located(..), mkGeneralSrcSpan, getLoc, - unLoc, noLoc, srcLocSpan, SrcSpan ) +import SrcLoc import FiniteMap import ErrUtils import BasicTypes ( DeprecTxt ) @@ -81,29 +65,16 @@ rnImports imports -- warning for {- SOURCE -} ones that are unnecessary = do this_mod <- getModule implicit_prelude <- doptM Opt_ImplicitPrelude - let all_imports = mk_prel_imports this_mod implicit_prelude ++ imports - (source, ordinary) = partition is_source_import all_imports + let prel_imports = mkPrelImports this_mod implicit_prelude imports + (source, ordinary) = partition is_source_import imports is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot - stuff1 <- mapM (rnImportDecl this_mod) ordinary + stuff1 <- mapM (rnImportDecl this_mod) (prel_imports ++ ordinary) stuff2 <- mapM (rnImportDecl this_mod) source let (decls, rdr_env, imp_avails) = combine (stuff1 ++ stuff2) return (decls, rdr_env, imp_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 implicit_prelude - | this_mod == pRELUDE - || explicit_prelude_import - || not implicit_prelude - = [] - | otherwise = [preludeImportDecl] - explicit_prelude_import - = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports, - unLoc mod == pRELUDE_NAME ] - combine :: [(LImportDecl Name, GlobalRdrEnv, ImportAvails)] -> ([LImportDecl Name], GlobalRdrEnv, ImportAvails) combine = foldr plus ([], emptyGlobalRdrEnv, emptyImportAvails) @@ -113,18 +84,34 @@ rnImports imports gbl_env1 `plusGlobalRdrEnv` gbl_env2, imp_avails1 `plusImportAvails` imp_avails2) -preludeImportDecl :: LImportDecl RdrName -preludeImportDecl - = L loc $ - ImportDecl (L loc pRELUDE_NAME) +mkPrelImports :: Module -> Bool -> [LImportDecl RdrName] -> [LImportDecl RdrName] +-- Consruct the implicit declaration "import Prelude" (or not) +-- +-- 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. +mkPrelImports this_mod implicit_prelude import_decls + | this_mod == pRELUDE + || explicit_prelude_import + || not implicit_prelude + = [] + | otherwise = [preludeImportDecl] + where + explicit_prelude_import + = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- import_decls, + unLoc mod == pRELUDE_NAME ] + + preludeImportDecl :: LImportDecl RdrName + 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") - + loc = mkGeneralSrcSpan FSLIT("Implicit import declaration") + rnImportDecl :: Module -> LImportDecl RdrName @@ -812,14 +799,13 @@ exports_from_avail (Just rdr_items) rdr_env imports this_mod return (IEVar (gre_name gre), greAvail gre) lookup_ie (IEThingAbs rdr) - = do name <- lookupGlobalOccRn rdr - case lookupGRE_RdrName rdr rdr_env of - [] -> panic "RnNames.lookup_ie" - elt:_ -> case gre_par elt of - NoParent -> return (IEThingAbs name, - AvailTC name [name]) - ParentIs p -> return (IEThingAbs name, - AvailTC p [name]) + = do gre <- lookupGreRn rdr + let name = gre_name gre + case gre_par gre of + NoParent -> return (IEThingAbs name, + AvailTC name [name]) + ParentIs p -> return (IEThingAbs name, + AvailTC p [name]) lookup_ie ie@(IEThingAll rdr) = do name <- lookupGlobalOccRn rdr @@ -932,7 +918,7 @@ reportDeprecations dflags tcg_env check hpt pit gre@(GRE {gre_name = name, gre_prov = Imported (imp_spec:_)}) | name `elemNameSet` used_names - , Just deprec_txt <- lookupDeprec dflags hpt pit gre + , Just deprec_txt <- lookupImpDeprec dflags hpt pit gre = addWarnAt (importSpecLoc imp_spec) (sep [ptext SLIT("Deprecated use of") <+> pprNonVarNameSpace (occNameSpace (nameOccName name)) <+> @@ -954,9 +940,10 @@ reportDeprecations dflags tcg_env -- the defn of a non-deprecated thing, when changing a module's -- interface -lookupDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable - -> GlobalRdrElt -> Maybe DeprecTxt -lookupDeprec dflags hpt pit gre +lookupImpDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable + -> GlobalRdrElt -> Maybe DeprecTxt +-- The name is definitely imported, so look in HPT, PIT +lookupImpDeprec dflags hpt pit gre = case lookupIfaceByModule dflags hpt pit (nameModule name) of Just iface -> mi_dep_fn iface name `seqMaybe` -- Bleat if the thing, *or case gre_par gre of @@ -1026,14 +1013,15 @@ reportUnusedNames export_decls gbl_env 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}) - = not (all (module_unused . importSpecModule) imp_specs) - && or [exp | ImpSpec { is_item = ImpSome { is_explicit = exp } } <- imp_specs] - -- Don't complain about unused imports if we've already said the - -- entire import is unused - unused_imp other = False + unused_imports :: [GlobalRdrElt] + unused_imports = mapCatMaybes unused_imp defined_but_not_used + unused_imp :: GlobalRdrElt -> Maybe GlobalRdrElt -- Result has trimmed Imported provenances + unused_imp gre@(GRE {gre_prov = LocalDef}) = Nothing + unused_imp gre@(GRE {gre_prov = Imported imp_specs}) + | null trimmed_specs = Nothing + | otherwise = Just (gre {gre_prov = Imported trimmed_specs}) + where + trimmed_specs = filter report_if_unused imp_specs -- 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 @@ -1109,6 +1097,7 @@ reportUnusedNames export_decls gbl_env -- -- BUG WARNING: does not deal correctly with multiple imports of the same module -- becuase direct_import_mods has only one entry per module + unused_imp_mods :: [(ModuleName, SrcSpan)] unused_imp_mods = [(mod_name,loc) | (mod,no_imp,loc) <- direct_import_mods, let mod_name = moduleName mod, not (mod_name `elemFM` minimal_imports1), @@ -1121,6 +1110,12 @@ reportUnusedNames export_decls gbl_env module_unused :: ModuleName -> Bool module_unused mod = any (((==) mod) . fst) unused_imp_mods + report_if_unused :: ImportSpec -> Bool + -- Do we want to report this as an unused import? + report_if_unused (ImpSpec {is_decl = d, is_item = i}) + = not (module_unused (is_mod d)) -- Not if we've already said entire import is unused + && isExplicitItem i -- Only if the import was explicit + --------------------- warnDuplicateImports :: [GlobalRdrElt] -> RnM () -- Given the GREs for names that are used, figure out which imports @@ -1139,8 +1134,6 @@ warnDuplicateImports :: [GlobalRdrElt] -> RnM () warnDuplicateImports 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 @@ -1159,7 +1152,12 @@ warnDuplicateImports gres redundants imps = [ (red_imp, cov_imp) | red_imp <- imps + , isExplicitItem (is_item red_imp) + -- Complain only about redundant imports + -- mentioned explicitly by the user , cov_imp <- take 1 (filter (covers red_imp) imps) ] + -- The 'take 1' picks the first offending group + -- for this particular name -- "red_imp" is a putative redundant import -- "cov_imp" potentially covers it @@ -1180,6 +1178,10 @@ warnDuplicateImports gres = False -- They bring into scope different qualified names | not (is_qual red_decl) && is_qual cov_decl = False -- Covering one doesn't bring unqualified name into scope + | otherwise + = not (isExplicitItem cov_item) -- Redundant one is selective and covering one isn't + || red_later -- or both are explicit; tie-break using red_later +{- | red_selective = not cov_selective -- Redundant one is selective and covering one isn't || red_later -- Both are explicit; tie-break using red_later @@ -1187,16 +1189,11 @@ warnDuplicateImports gres = not cov_selective -- Neither import is selective && (is_mod red_decl == is_mod cov_decl) -- They import the same module && red_later -- Tie-break +-} where red_loc = importSpecLoc red_imp cov_loc = importSpecLoc cov_imp red_later = red_loc > cov_loc - cov_selective = selectiveImpItem cov_item - red_selective = selectiveImpItem red_item - -selectiveImpItem :: ImpItemSpec -> Bool -selectiveImpItem ImpAll = False -selectiveImpItem (ImpSome {}) = True -- ToDo: deal with original imports with 'qualified' and 'as M' clauses printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports