diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/main/HscTypes.hs | 11 | ||||
| -rw-r--r-- | compiler/rename/RnEnv.hs | 222 | ||||
| -rw-r--r-- | compiler/rename/RnNames.hs | 1 | ||||
| -rw-r--r-- | compiler/typecheck/TcErrors.hs | 3 |
4 files changed, 129 insertions, 108 deletions
diff --git a/compiler/main/HscTypes.hs b/compiler/main/HscTypes.hs index 849c8035a8..d15dcd2c46 100644 --- a/compiler/main/HscTypes.hs +++ b/compiler/main/HscTypes.hs @@ -1032,11 +1032,12 @@ emptyModDetails type ImportedMods = ModuleEnv [ImportedModsVal] data ImportedModsVal = ImportedModsVal { - imv_name :: ModuleName, -- ^ The name the module is imported with - imv_span :: SrcSpan, -- ^ the source span of the whole import - imv_is_safe :: IsSafeImport, -- ^ whether this is a safe import - imv_is_hiding :: Bool, -- ^ whether this is an "hiding" import - imv_all_exports :: GlobalRdrEnv -- ^ all the things the module could provide + imv_name :: ModuleName, -- ^ The name the module is imported with + imv_span :: SrcSpan, -- ^ the source span of the whole import + imv_is_safe :: IsSafeImport, -- ^ whether this is a safe import + imv_is_hiding :: Bool, -- ^ whether this is an "hiding" import + imv_all_exports :: GlobalRdrEnv, -- ^ all the things the module could provide + imv_qualified :: Bool -- ^ whether this is a qualified import } -- | A ModGuts is carried through the compiler, accumulating stuff as it goes diff --git a/compiler/rename/RnEnv.hs b/compiler/rename/RnEnv.hs index 1e8eb27e9f..72455b0098 100644 --- a/compiler/rename/RnEnv.hs +++ b/compiler/rename/RnEnv.hs @@ -1637,10 +1637,9 @@ unboundNameX where_look rdr_name extra else do { local_env <- getLocalRdrEnv ; global_env <- getGlobalRdrEnv ; impInfo <- getImports - ; let suggestions1 = unknownNameSuggestions_ where_look - dflags global_env local_env rdr_name - ; let suggestions2 = importSuggestions dflags impInfo rdr_name - ; addErr (err $$ suggestions1 $$ suggestions2) } + ; let suggestions = unknownNameSuggestions_ where_look + dflags global_env local_env impInfo rdr_name + ; addErr (err $$ suggestions) } ; return (mkUnboundName rdr_name) } unknownNameErr :: SDoc -> RdrName -> SDoc @@ -1656,113 +1655,25 @@ type HowInScope = Either SrcSpan ImpDeclSpec -- Left loc => locally bound at loc -- Right ispec => imported as specified by ispec --- | Generate helpful suggestions if a qualified name Mod.foo is not in scope. -importSuggestions :: DynFlags -> ImportAvails -> RdrName -> SDoc -importSuggestions _dflags imports rdr_name - | not (isQual rdr_name) = Outputable.empty - | null interesting_imports - = hsep - [ ptext (sLit "No module named") - , quotes (ppr mod_name) - , ptext (sLit "is imported.") - ] - | null helpful_imports - , [(mod,_)] <- interesting_imports - = hsep - [ ptext (sLit "Module") - , quotes (ppr mod) - , ptext (sLit "does not export") - , quotes (ppr occ_name) <> dot - ] - | null helpful_imports - , mods <- map fst interesting_imports - = hsep - [ ptext (sLit "Neither") - , quotedListWithNor (map ppr mods) - , ptext (sLit "exports") - , quotes (ppr occ_name) <> dot - ] - | [(mod,imv)] <- helpful_imports_non_hiding - = fsep - [ ptext (sLit "Perhaps you want to add") - , quotes (ppr occ_name) - , ptext (sLit "to the import list") - , ptext (sLit "in the import of") - , quotes (ppr mod) - , parens (ppr (imv_span imv)) <> dot - ] - | not (null helpful_imports_non_hiding) - = fsep - [ ptext (sLit "Perhaps you want to add") - , quotes (ppr occ_name) - , ptext (sLit "to one of these import lists:") - ] - $$ - nest 2 (vcat - [ quotes (ppr mod) <+> parens (ppr (imv_span imv)) - | (mod,imv) <- helpful_imports_non_hiding - ]) - | [(mod,imv)] <- helpful_imports_hiding - = fsep - [ ptext (sLit "Perhaps you want to remove") - , quotes (ppr occ_name) - , ptext (sLit "from the explicit hiding list") - , ptext (sLit "in the import of") - , quotes (ppr mod) - , parens (ppr (imv_span imv)) <> dot - ] - | not (null helpful_imports_hiding) - = fsep - [ ptext (sLit "Perhaps you want to remove") - , quotes (ppr occ_name) - , ptext (sLit "from the hiding clauses") - , ptext (sLit "in one of these imports:") - ] - $$ - nest 2 (vcat - [ quotes (ppr mod) <+> parens (ppr (imv_span imv)) - | (mod,imv) <- helpful_imports_hiding - ]) - | otherwise - = Outputable.empty - where - Just (mod_name, occ_name) = isQual_maybe rdr_name - - -- What import statements provide "Mod" at all - interesting_imports = [ (mod, imp) - | (mod, mod_imports) <- moduleEnvToList (imp_mods imports) - , Just imp <- return $ pick mod_imports - ] - - -- We want to keep only one for each original module; preferably one with an - -- explicit import list (for no particularly good reason) - pick :: [ImportedModsVal] -> Maybe ImportedModsVal - pick = listToMaybe . sortBy (compare `on` prefer) . filter select - where select imv = imv_name imv == mod_name - prefer imv = (imv_is_hiding imv, imv_span imv) - - -- Which of these would export a 'foo' - -- (all of these are restricted imports, because if they were not, we - -- wouldn't have an out-of-scope error in the first place) - helpful_imports = filter helpful interesting_imports - where helpful (_,imv) - = not . null $ lookupGlobalRdrEnv (imv_all_exports imv) occ_name - - -- Which of these do that because of an explicit hiding list resp. an - -- explicit import list - (helpful_imports_hiding, helpful_imports_non_hiding) - = partition (imv_is_hiding . snd) helpful_imports -- | Called from the typechecker (TcErrors) when we find an unbound variable unknownNameSuggestions :: DynFlags - -> GlobalRdrEnv -> LocalRdrEnv + -> GlobalRdrEnv -> LocalRdrEnv -> ImportAvails -> RdrName -> SDoc unknownNameSuggestions = unknownNameSuggestions_ WL_Any unknownNameSuggestions_ :: WhereLooking -> DynFlags + -> GlobalRdrEnv -> LocalRdrEnv -> ImportAvails + -> RdrName -> SDoc +unknownNameSuggestions_ where_look dflags global_env local_env imports tried_rdr_name = + similarNameSuggestions where_look dflags global_env local_env tried_rdr_name $$ + importSuggestions dflags imports tried_rdr_name + + +similarNameSuggestions :: WhereLooking -> DynFlags -> GlobalRdrEnv -> LocalRdrEnv -> RdrName -> SDoc -unknownNameSuggestions_ where_look dflags global_env +similarNameSuggestions where_look dflags global_env local_env tried_rdr_name = case suggest of [] -> Outputable.empty @@ -1876,6 +1787,113 @@ unknownNameSuggestions_ where_look dflags global_env = [ (mkRdrQual (is_as ispec) (nameOccName n), Right ispec) | i <- is, let ispec = is_decl i, is_qual ispec ] +-- | Generate helpful suggestions if a qualified name Mod.foo is not in scope. +importSuggestions :: DynFlags -> ImportAvails -> RdrName -> SDoc +importSuggestions _dflags imports rdr_name + | not (isQual rdr_name || isUnqual rdr_name) = Outputable.empty + | null interesting_imports + , Just name <- mod_name + = hsep + [ ptext (sLit "No module named") + , quotes (ppr name) + , ptext (sLit "is imported.") + ] + | is_qualified + , null helpful_imports + , [(mod,_)] <- interesting_imports + = hsep + [ ptext (sLit "Module") + , quotes (ppr mod) + , ptext (sLit "does not export") + , quotes (ppr occ_name) <> dot + ] + | is_qualified + , null helpful_imports + , mods <- map fst interesting_imports + = hsep + [ ptext (sLit "Neither") + , quotedListWithNor (map ppr mods) + , ptext (sLit "exports") + , quotes (ppr occ_name) <> dot + ] + | [(mod,imv)] <- helpful_imports_non_hiding + = fsep + [ ptext (sLit "Perhaps you want to add") + , quotes (ppr occ_name) + , ptext (sLit "to the import list") + , ptext (sLit "in the import of") + , quotes (ppr mod) + , parens (ppr (imv_span imv)) <> dot + ] + | not (null helpful_imports_non_hiding) + = fsep + [ ptext (sLit "Perhaps you want to add") + , quotes (ppr occ_name) + , ptext (sLit "to one of these import lists:") + ] + $$ + nest 2 (vcat + [ quotes (ppr mod) <+> parens (ppr (imv_span imv)) + | (mod,imv) <- helpful_imports_non_hiding + ]) + | [(mod,imv)] <- helpful_imports_hiding + = fsep + [ ptext (sLit "Perhaps you want to remove") + , quotes (ppr occ_name) + , ptext (sLit "from the explicit hiding list") + , ptext (sLit "in the import of") + , quotes (ppr mod) + , parens (ppr (imv_span imv)) <> dot + ] + | not (null helpful_imports_hiding) + = fsep + [ ptext (sLit "Perhaps you want to remove") + , quotes (ppr occ_name) + , ptext (sLit "from the hiding clauses") + , ptext (sLit "in one of these imports:") + ] + $$ + nest 2 (vcat + [ quotes (ppr mod) <+> parens (ppr (imv_span imv)) + | (mod,imv) <- helpful_imports_hiding + ]) + | otherwise + = Outputable.empty + where + is_qualified = isQual rdr_name + (mod_name, occ_name) = case rdr_name of + Unqual occ_name -> (Nothing, occ_name) + Qual mod_name occ_name -> (Just mod_name, occ_name) + _ -> error "importSuggestions: dead code" + + + -- What import statements provide "Mod" at all + -- or, if this is an unqualified name, are not qualified imports + interesting_imports = [ (mod, imp) + | (mod, mod_imports) <- moduleEnvToList (imp_mods imports) + , Just imp <- return $ pick mod_imports + ] + + -- We want to keep only one for each original module; preferably one with an + -- explicit import list (for no particularly good reason) + pick :: [ImportedModsVal] -> Maybe ImportedModsVal + pick = listToMaybe . sortBy (compare `on` prefer) . filter select + where select imv = case mod_name of Just name -> imv_name imv == name + Nothing -> not (imv_qualified imv) + prefer imv = (imv_is_hiding imv, imv_span imv) + + -- Which of these would export a 'foo' + -- (all of these are restricted imports, because if they were not, we + -- wouldn't have an out-of-scope error in the first place) + helpful_imports = filter helpful interesting_imports + where helpful (_,imv) + = not . null $ lookupGlobalRdrEnv (imv_all_exports imv) occ_name + + -- Which of these do that because of an explicit hiding list resp. an + -- explicit import list + (helpful_imports_hiding, helpful_imports_non_hiding) + = partition (imv_is_hiding . snd) helpful_imports + {- ************************************************************************ * * diff --git a/compiler/rename/RnNames.hs b/compiler/rename/RnNames.hs index 8d4986e969..32f0f9420f 100644 --- a/compiler/rename/RnNames.hs +++ b/compiler/rename/RnNames.hs @@ -284,6 +284,7 @@ rnImportDecl this_mod , imv_is_safe = mod_safe' , imv_is_hiding = is_hiding , imv_all_exports = potential_gres + , imv_qualified = qual_only } let imports = (calculateAvails dflags iface mod_safe' want_boot) diff --git a/compiler/typecheck/TcErrors.hs b/compiler/typecheck/TcErrors.hs index 8c88d22dd3..876bd7ccef 100644 --- a/compiler/typecheck/TcErrors.hs +++ b/compiler/typecheck/TcErrors.hs @@ -699,9 +699,10 @@ mkHoleError ctxt ct@(CHoleCan { cc_occ = occ, cc_hole = hole_sort }) -- Suggest possible in-scope variables in the message = do { dflags <- getDynFlags ; rdr_env <- getGlobalRdrEnv + ; impInfo <- getImports ; mkLongErrAt (RealSrcSpan (tcl_loc lcl_env)) out_of_scope_msg (unknownNameSuggestions dflags rdr_env - (tcl_rdr lcl_env) (mkRdrUnqual occ)) } + (tcl_rdr lcl_env) impInfo (mkRdrUnqual occ)) } | otherwise -- Explicit holes, like "_" or "_f" = do { (ctxt, binds_doc, ct) <- relevantBindings False ctxt ct |