\begin{code}
module RnNames (
rnImports, getLocalNonValBinders,
- rnExports, extendGlobalRdrEnvRn,
+ rnExports, extendGlobalRdrEnvRn,
+ gresFromAvails,
reportUnusedNames, finishWarnings,
) where
import RnEnv
import RnHsDoc ( rnHsDoc )
import IfaceEnv ( ifaceExportNames )
-import LoadIface ( loadSrcInterface, loadSysInterface )
-import TcRnMonad hiding (LIE)
+import LoadIface ( loadSrcInterface )
+import TcRnMonad
+import HeaderInfo ( mkPrelImports )
import PrelNames
import Module
import Name
import Outputable
import Maybes
import SrcLoc
-import FiniteMap
import ErrUtils
import Util
import FastString
import ListSetOps
import Data.List ( partition, (\\), delete )
import qualified Data.Set as Set
-import IO ( openFile, IOMode(..) )
-import Monad ( when, mplus )
+import System.IO
+import Control.Monad
+import Data.Map (Map)
+import qualified Data.Map as Map
\end{code}
-- Do the non {- SOURCE -} ones first, so that we get a helpful
-- warning for {- SOURCE -} ones that are unnecessary
= do this_mod <- getModule
- implicit_prelude <- doptM Opt_ImplicitPrelude
- let prel_imports = mkPrelImports this_mod implicit_prelude imports
+ implicit_prelude <- xoptM Opt_ImplicitPrelude
+ let prel_imports = mkPrelImports (moduleName this_mod) implicit_prelude imports
(source, ordinary) = partition is_source_import imports
is_source_import (L _ (ImportDecl _ _ is_boot _ _ _)) = is_boot
- ifOptM Opt_WarnImplicitPrelude (
+ ifDOptM Opt_WarnImplicitPrelude (
when (notNull prel_imports) $ addWarn (implicitPreludeWarn)
)
- stuff1 <- mapM (rnImportDecl this_mod) (prel_imports ++ ordinary)
- stuff2 <- mapM (rnImportDecl this_mod) source
- let (decls, rdr_env, imp_avails,hpc_usage) = combine (stuff1 ++ stuff2)
- return (decls, rdr_env, imp_avails,hpc_usage)
+ stuff1 <- mapM (rnImportDecl this_mod True) prel_imports
+ stuff2 <- mapM (rnImportDecl this_mod False) ordinary
+ stuff3 <- mapM (rnImportDecl this_mod False) source
+ let (decls, rdr_env, imp_avails, hpc_usage) = combine (stuff1 ++ stuff2 ++ stuff3)
+ return (decls, rdr_env, imp_avails, hpc_usage)
where
combine :: [(LImportDecl Name, GlobalRdrEnv, ImportAvails,AnyHpcUsage)]
imp_avails1 `plusImportAvails` imp_avails2,
hpc_usage1 || hpc_usage2)
-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 Nothing _ _ _ _) <- import_decls,
- unLoc mod == pRELUDE_NAME ]
-
- preludeImportDecl :: LImportDecl RdrName
- preludeImportDecl
- = L loc $
- ImportDecl (L loc pRELUDE_NAME)
- Nothing {- no specific package -}
- False {- Not a boot interface -}
- False {- Not qualified -}
- Nothing {- No "as" -}
- Nothing {- No import list -}
-
- loc = mkGeneralSrcSpan (fsLit "Implicit import declaration")
-
-
-rnImportDecl :: Module
+rnImportDecl :: Module -> Bool
-> LImportDecl RdrName
-> RnM (LImportDecl Name, GlobalRdrEnv, ImportAvails,AnyHpcUsage)
-rnImportDecl this_mod (L loc (ImportDecl loc_imp_mod_name mb_pkg want_boot
- qual_only as_mod imp_details))
+rnImportDecl this_mod implicit_prelude
+ (L loc (ImportDecl { ideclName = loc_imp_mod_name, ideclPkgQual = mb_pkg
+ , ideclSource = want_boot, ideclQualified = qual_only
+ , ideclAs = as_mod, ideclHiding = imp_details }))
= setSrcSpan loc $ do
when (isJust mb_pkg) $ do
- pkg_imports <- doptM Opt_PackageImports
+ pkg_imports <- xoptM Opt_PackageImports
when (not pkg_imports) $ addErr packageImportErr
-- If there's an error in loadInterface, (e.g. interface
imp_mod_name = unLoc loc_imp_mod_name
doc = ppr imp_mod_name <+> ptext (sLit "is directly imported")
+ let isExplicit lie = case unLoc lie of
+ IEThingAll _ -> False
+ _ -> True
+ case imp_details of
+ Just (False, lies)
+ | all isExplicit lies ->
+ return ()
+ _ ->
+ unless implicit_prelude $
+ ifDOptM Opt_WarnMissingImportList (addWarn (missingImportListWarn imp_mod_name))
+
iface <- loadSrcInterface doc imp_mod_name want_boot mb_pkg
-- Compiler sanity check: if the import didn't say
}
-- Complain if we import a deprecated module
- ifOptM Opt_WarnWarningsDeprecations (
+ ifDOptM Opt_WarnWarningsDeprecations (
case warns of
WarnAll txt -> addWarn (moduleWarn imp_mod_name txt)
_ -> return ()
2. We make them *shadow* the outer bindings. If we don't do that,
we'll get a complaint when extending the GlobalRdrEnv, saying that
- there are two bindings for 'f'.
-
- This shadowing applies even if the binding for 'f' is in a
- where-clause, and hence is in the *local* RdrEnv not the *global*
- RdrEnv.
-
-We find out whether we are inside a [d| ... |] by testing the TH
-stage. This is a slight hack, because the stage field was really meant for
-the type checker, and here we are not interested in the fields of Brack,
-hence the error thunks in thRnBrack.
+ there are two bindings for 'f'. There are several tricky points:
+
+ * This shadowing applies even if the binding for 'f' is in a
+ where-clause, and hence is in the *local* RdrEnv not the *global*
+ RdrEnv.
+
+ * The *qualified* name M.f from the enclosing module must certainly
+ still be available. So we don't nuke it entirely; we just make
+ it seem like qualified import.
+
+ * We only shadow *External* names (which come from the main module)
+ Do not shadow *Inernal* names because in the bracket
+ [d| class C a where f :: a
+ f = 4 |]
+ rnSrcDecls will first call extendGlobalRdrEnvRn with C[f] from the
+ class decl, and *separately* extend the envt with the value binding.
+
+3. We find out whether we are inside a [d| ... |] by testing the TH
+ stage. This is a slight hack, because the stage field was really
+ meant for the type checker, and here we are not interested in the
+ fields of Brack, hence the error thunks in thRnBrack.
\begin{code}
extendGlobalRdrEnvRn :: [AvailInfo]
-> MiniFixityEnv
-> RnM (TcGblEnv, TcLclEnv)
-- Updates both the GlobalRdrEnv and the FixityEnv
- -- We return a new TcLclEnv only becuase we might have to
+ -- We return a new TcLclEnv only because we might have to
-- delete some bindings from it;
-- see Note [Top-level Names in Template Haskell decl quotes]
-- See Note [Top-level Names in Template Haskell decl quotes]
shadowP = isBrackStage stage
new_occs = map (nameOccName . gre_name) gres
- rdr_env1 = hideSomeUnquals rdr_env new_occs
+ rdr_env1 = transformGREs qual_gre new_occs rdr_env
lcl_env1 = lcl_env { tcl_rdr = delListFromOccEnv (tcl_rdr lcl_env) new_occs }
(rdr_env2, lcl_env2) | shadowP = (rdr_env1, lcl_env1)
| otherwise = (rdr_env, lcl_env)
where
name = gre_name gre
occ = nameOccName name
+
+ qual_gre :: GlobalRdrElt -> GlobalRdrElt
+ -- Transform top-level GREs from the module being compiled
+ -- so that they are out of the way of new definitions in a Template
+ -- Haskell bracket
+ -- See Note [Top-level Names in Template Haskell decl quotes]
+ -- Seems like 5 times as much work as it deserves!
+ --
+ -- For a LocalDef we make a (fake) qualified imported GRE for a
+ -- local GRE so that the original *qualified* name is still in scope
+ -- but the *unqualified* one no longer is. What a hack!
+
+ qual_gre gre@(GRE { gre_prov = LocalDef, gre_name = name })
+ | isExternalName name = gre { gre_prov = Imported [imp_spec] }
+ | otherwise = gre
+ -- Do not shadow Internal (ie Template Haskell) Names
+ -- See Note [Top-level Names in Template Haskell decl quotes]
+ where
+ mod = ASSERT2( isExternalName name, ppr name) moduleName (nameModule name)
+ imp_spec = ImpSpec { is_item = ImpAll, is_decl = decl_spec }
+ decl_spec = ImpDeclSpec { is_mod = mod, is_as = mod,
+ is_qual = True, -- Qualified only!
+ is_dloc = srcLocSpan (nameSrcLoc name) }
+
+ qual_gre gre@(GRE { gre_prov = Imported specs })
+ = gre { gre_prov = Imported (map qual_spec specs) }
+
+ qual_spec spec@(ImpSpec { is_decl = decl_spec })
+ = spec { is_decl = decl_spec { is_qual = True } }
\end{code}
@getLocalDeclBinders@ returns the names for an @HsDecl@. It's
-- Get all the top-level binders bound the group *except*
-- for value bindings, which are treated separately
-- Specificaly we return AvailInfo for
--- type decls
--- class decls
+-- type decls (incl constructors and record selectors)
+-- class decls (including class ops)
-- associated types
-- foreign imports
-- (in hs-boot files) value signatures
= do { -- separate out the family instance declarations
let (tyinst_decls1, tycl_decls_noinsts)
= partition (isFamInstDecl . unLoc) tycl_decls
- tyinst_decls = tyinst_decls1 ++
- concatMap (instDeclATs . unLoc) inst_decls
+ tyinst_decls = tyinst_decls1 ++ instDeclATs inst_decls
-- process all type/class decls except family instances
; tc_names <- mapM new_tc tycl_decls_noinsts
; val_names <- mapM new_simple val_bndrs
; return (val_names ++ tc_names ++ ti_names) }
where
- mod = tcg_mod gbl_env
is_hs_boot = isHsBoot (tcg_src gbl_env) ;
for_hs_bndrs :: [Located RdrName]
new_simple :: Located RdrName -> RnM (GenAvailInfo Name)
new_simple rdr_name = do
- nm <- newTopSrcBinder mod rdr_name
+ nm <- newTopSrcBinder rdr_name
return (Avail nm)
new_tc tc_decl -- NOT for type/data instances
- = do { main_name <- newTopSrcBinder mod main_rdr
- ; sub_names <- mapM (newTopSrcBinder mod) sub_rdrs
+ = do { main_name <- newTopSrcBinder main_rdr
+ ; sub_names <- mapM newTopSrcBinder sub_rdrs
; return (AvailTC main_name (main_name : sub_names)) }
where
- (main_rdr : sub_rdrs) = tyClDeclNames (unLoc tc_decl)
+ (main_rdr : sub_rdrs) = hsTyClDeclBinders tc_decl
new_ti tc_name_env ti_decl -- ONLY for type/data instances
= do { main_name <- lookupFamInstDeclBndr tc_name_env main_rdr
- ; sub_names <- mapM (newTopSrcBinder mod) sub_rdrs
+ ; sub_names <- mapM newTopSrcBinder sub_rdrs
; return (AvailTC main_name sub_names) }
-- main_name is not bound here!
where
- (main_rdr : sub_rdrs) = tyClDeclNames (unLoc ti_decl)
+ (main_rdr : sub_rdrs) = hsTyClDeclBinders ti_decl
get_local_binders _ g = pprPanic "get_local_binders" (ppr g)
\end{code}
filterImports iface decl_spec (Just (want_hiding, import_items)) all_avails
= do -- check for errors, convert RdrNames to Names
- opt_typeFamilies <- doptM Opt_TypeFamilies
+ opt_typeFamilies <- xoptM Opt_TypeFamilies
items1 <- mapM (lookup_lie opt_typeFamilies) import_items
let items2 :: [(LIE Name, AvailInfo)]
-- Warn when importing T(..) if T was exported abstractly
checkDodgyImport stuff
| IEThingAll n <- ieRdr, (_, AvailTC _ [_]):_ <- stuff
- = ifOptM Opt_WarnDodgyImports (addWarn (dodgyImportWarn n))
+ = ifDOptM Opt_WarnDodgyImports (addWarn (dodgyImportWarn n))
-- NB. use the RdrName for reporting the warning
checkDodgyImport _
= return ()
-- different parents). See the discussion at occ_env.
lookup_ie :: Bool -> IE RdrName -> MaybeErr Message [(IE Name,AvailInfo)]
lookup_ie opt_typeFamilies ie
- = let bad_ie = Failed (badImportItemErr iface decl_spec ie)
+ = let bad_ie :: MaybeErr Message a
+ bad_ie = Failed (badImportItemErr iface decl_spec ie)
- lookup_name rdrName =
- case lookupOccEnv occ_env (rdrNameOcc rdrName) of
- Nothing -> bad_ie
- Just n -> return n
+ lookup_name rdr
+ | isQual rdr = Failed (qualImportItemErr rdr)
+ | Just nm <- lookupOccEnv occ_env (rdrNameOcc rdr) = return nm
+ | otherwise = bad_ie
in
case ie of
IEVar n -> do
mkChildEnv :: [GlobalRdrElt] -> NameEnv [Name]
mkChildEnv gres = foldr add emptyNameEnv gres
where
- add (GRE { gre_name = n, gre_par = ParentIs p }) env = extendNameEnv_C (++) env p [n]
+ add (GRE { gre_name = n, gre_par = ParentIs p }) env = extendNameEnv_Acc (:) singleton env p n
add _ env = env
findChildren :: NameEnv [Name] -> Name -> [Name]
return acc }
| otherwise
- = do { implicit_prelude <- doptM Opt_ImplicitPrelude
+ = do { implicit_prelude <- xoptM Opt_ImplicitPrelude
; warnDodgyExports <- doptM Opt_WarnDodgyExports
; let { exportValid = (mod `elem` imported_modules)
|| (moduleName this_mod == mod)
then do addErr (exportItemErr ie)
return (IEThingWith name [], AvailTC name [name])
else do let names = catMaybes mb_names
- optTyFam <- doptM Opt_TypeFamilies
+ optTyFam <- xoptM Opt_TypeFamilies
when (not optTyFam && any isTyConName names) $
addErr (typeItemErr ( head
. filter isTyConName
-- All this happens only once per module
finishWarnings dflags mod_warn tcg_env
= do { (eps,hpt) <- getEpsAndHpt
- ; ifOptM Opt_WarnWarningsDeprecations $
+ ; ifDOptM Opt_WarnWarningsDeprecations $
mapM_ (check hpt (eps_PIT eps)) all_gres
-- By this time, typechecking is complete,
-- so the PIT is fully populated
its interface (although we could).
b) It might be GHC.Real.fromRational, or GHC.Num.fromInteger
- These are seen as "used" by the renamer (if -XNoImplicitPrelude)
+ These are seen as "used" by the renamer (if -XRebindableSyntax)
is on), but the typechecker may discard their uses
if in fact the in-scope fromRational is GHC.Read.fromRational,
(see tcPat.tcOverloadedLit), and the typechecker sees that the type
; let usage :: [ImportDeclUsage]
usage = findImportUsage imports rdr_env (Set.elems uses)
- ; ifOptM Opt_WarnUnusedImports $
+ ; ifDOptM Opt_WarnUnusedImports $
mapM_ warnUnusedImport usage
- ; ifOptM Opt_D_dump_minimal_imports $
+ ; ifDOptM Opt_D_dump_minimal_imports $
printMinimalImports usage }
where
explicit_import (L loc _) = isGoodSrcSpan loc
-> [RdrName]
-> [ImportDeclUsage]
-type ImportMap = FiniteMap SrcLoc [AvailInfo]
+type ImportMap = Map SrcLoc [AvailInfo]
-- The intermediate data struture records, for each import
-- declaration, what stuff brought into scope by that
-- declaration is actually used in the module.
= map unused_decl imports
where
import_usage :: ImportMap
- import_usage = foldr add_rdr emptyFM rdrs
+ import_usage = foldr (addUsedRdrName rdr_env) Map.empty rdrs
unused_decl decl@(L loc (ImportDecl { ideclHiding = imps }))
= (decl, nubAvails used_avails, unused_imps)
where
- used_avails = lookupFM import_usage (srcSpanStart loc) `orElse` []
- used_names = availsToNameSet used_avails
+ used_avails = Map.lookup (srcSpanStart loc) import_usage `orElse` []
+ dont_report_as_unused = foldr add emptyNameSet used_avails
+ add (Avail n) s = s `addOneToNameSet` n
+ add (AvailTC n ns) s = s `addListToNameSet` (n:ns)
+ -- If you use 'signum' from Num, then the user may well have
+ -- imported Num(signum). We don't want to complain that
+ -- Num is not itself mentioned. Hence adding 'n' as
+ -- well to the list of of "don't report if unused" names
unused_imps = case imps of
Just (False, imp_ies) -> nameSetToList unused_imps
where
imp_names = mkNameSet (concatMap (ieNames . unLoc) imp_ies)
- unused_imps = imp_names `minusNameSet` used_names
+ unused_imps = imp_names `minusNameSet` dont_report_as_unused
_other -> [] -- No explicit import list => no unused-name list
- add_rdr :: RdrName -> ImportMap -> ImportMap
- add_rdr rdr iu
- = case lookupGRE_RdrName rdr rdr_env of
- [gre] | Imported imps <- gre_prov gre
- -> add_imp gre (bestImport imps) iu
- _other -> iu
-
+addUsedRdrName :: GlobalRdrEnv -> RdrName -> ImportMap -> ImportMap
+-- For a used RdrName, find all the import decls that brought
+-- it into scope; choose one of them (bestImport), and record
+-- the RdrName in that import decl's entry in the ImportMap
+addUsedRdrName rdr_env rdr imp_map
+ | [gre] <- lookupGRE_RdrName rdr rdr_env
+ , Imported imps <- gre_prov gre
+ = add_imp gre (bestImport imps) imp_map
+ | otherwise
+ = imp_map
+ where
add_imp :: GlobalRdrElt -> ImportSpec -> ImportMap -> ImportMap
- add_imp gre (ImpSpec { is_decl = imp_decl_spec }) iu
- = addToFM_C add iu decl_loc [avail]
+ add_imp gre (ImpSpec { is_decl = imp_decl_spec }) imp_map
+ = Map.insertWith add decl_loc [avail] imp_map
where
- add avails _ = avail : avails
+ add _ avails = avail : avails -- add is really just a specialised (++)
decl_loc = srcSpanStart (is_dloc imp_decl_spec)
name = gre_name gre
avail = case gre_par gre of
- ParentIs p -> AvailTC p [p,name]
+ ParentIs p -> AvailTC p [name]
NoParent | isTyConName name -> AvailTC name [name]
| otherwise -> Avail name
- -- If you use (+) from Num, then for this purpose we want
- -- to say that Num is used as well. That is why in the
- -- ParentIs case we have [p,name] in the ParentIs case
-
-bestImport :: [ImportSpec] -> ImportSpec
-bestImport iss
- = case partition isImpAll iss of
- ([], imp_somes) -> textuallyFirst imp_somes
- (imp_alls, _) -> textuallyFirst imp_alls
-
-textuallyFirst :: [ImportSpec] -> ImportSpec
-textuallyFirst iss = case sortWith (is_dloc . is_decl) iss of
- [] -> pprPanic "textuallyFirst" (ppr iss)
- (is:_) -> is
-
-isImpAll :: ImportSpec -> Bool
-isImpAll (ImpSpec { is_item = ImpAll }) = True
-isImpAll _other = False
+
+ bestImport :: [ImportSpec] -> ImportSpec
+ bestImport iss
+ = case partition isImpAll iss of
+ ([], imp_somes) -> textuallyFirst imp_somes
+ (imp_alls, _) -> textuallyFirst imp_alls
+
+ textuallyFirst :: [ImportSpec] -> ImportSpec
+ textuallyFirst iss = case sortWith (is_dloc . is_decl) iss of
+ [] -> pprPanic "textuallyFirst" (ppr iss)
+ (is:_) -> is
+
+ isImpAll :: ImportSpec -> Bool
+ isImpAll (ImpSpec { is_item = ImpAll }) = True
+ isImpAll _other = False
\end{code}
\begin{code}
warnUnusedImport :: ImportDeclUsage -> RnM ()
-warnUnusedImport (L loc decl, used, unused)
- | Just (False,[]) <- ideclHiding decl
- = return () -- Do not warn for 'import M()'
+warnUnusedImport (L loc decl, used, unused)
+ | Just (False,[]) <- ideclHiding decl
+ = return () -- Do not warn for 'import M()'
| null used = addWarnAt loc msg1 -- Nothing used; drop entire decl
- | null unused = return () -- Everything imported is used; nop
+ | null unused = return () -- Everything imported is used; nop
| otherwise = addWarnAt loc msg2 -- Some imports are unused
where
msg1 = vcat [pp_herald <+> quotes pp_mod <+> pp_not_used,
- nest 2 (ptext (sLit "except perhaps to import instances from")
- <+> quotes pp_mod),
- ptext (sLit "To import instances alone, use:")
- <+> ptext (sLit "import") <+> pp_mod <> parens empty ]
+ nest 2 (ptext (sLit "except perhaps to import instances from")
+ <+> quotes pp_mod),
+ ptext (sLit "To import instances alone, use:")
+ <+> ptext (sLit "import") <+> pp_mod <> parens empty ]
msg2 = sep [pp_herald <+> quotes (pprWithCommas ppr unused),
- text "from module" <+> quotes pp_mod <+> pp_not_used]
+ text "from module" <+> quotes pp_mod <+> pp_not_used]
pp_herald = text "The import of"
pp_mod = ppr (unLoc (ideclName decl))
pp_not_used = text "is redundant"
, Just (False, _) <- ideclHiding decl
= return (L l decl)
| otherwise
- = do { ies <- initIfaceTcRn $ mapM to_ie used
- ; return (L l (decl { ideclHiding = Just (False, map (L l) ies) })) }
+ = do { let ImportDecl { ideclName = L _ mod_name
+ , ideclSource = is_boot
+ , ideclPkgQual = mb_pkg } = decl
+ ; iface <- loadSrcInterface doc mod_name is_boot mb_pkg
+ ; let lies = map (L l) (concatMap (to_ie iface) used)
+ ; return (L l (decl { ideclHiding = Just (False, lies) })) }
+ where
+ doc = text "Compute minimal imports for" <+> ppr decl
- to_ie :: AvailInfo -> IfG (IE Name)
+ to_ie :: ModIface -> AvailInfo -> [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) = return (IEVar n)
- to_ie (AvailTC n [m]) = ASSERT( n==m )
- return (IEThingAbs n)
- to_ie (AvailTC n ns) = do
- iface <- loadSysInterface doc n_mod
- case [xs | (m,as) <- mi_exports iface,
- m == n_mod,
- AvailTC x xs <- as,
- x == nameOccName n] of
- [xs] | all_used xs -> return (IEThingAll n)
- | otherwise -> return (IEThingWith n (filter (/= n) ns))
- other -> pprTrace "to_ie" (ppr n <+> ppr n_mod <+> ppr other) $
- return (IEVar n)
+ to_ie _ (Avail n)
+ = [IEVar n]
+ to_ie _ (AvailTC n [m])
+ | n==m = [IEThingAbs n]
+ to_ie iface (AvailTC n ns)
+ = case [xs | (m,as) <- mi_exports iface
+ , m == n_mod
+ , AvailTC x xs <- as
+ , x == nameOccName n
+ , x `elem` xs -- Note [Partial export]
+ ] of
+ [xs] | all_used xs -> [IEThingAll n]
+ | otherwise -> [IEThingWith n (filter (/= n) ns)]
+ _other -> (map IEVar ns)
where
all_used avail_occs = all (`elem` map nameOccName ns) avail_occs
- doc = text "Compute minimal imports from" <+> ppr n
n_mod = ASSERT( isExternalName n ) nameModule n
\end{code}
+Note [Partial export]
+~~~~~~~~~~~~~~~~~~~~~
+Suppose we have
+
+ module A( op ) where
+ class C a where
+ op :: a -> a
+
+ module B where
+ import A
+ f = ..op...
+
+Then the minimal import for module B is
+ import A( op )
+not
+ import A( C( op ) )
+which we would usually generate if C was exported from B. Hence
+the (x `elem` xs) test when deciding what to generate.
+
+
%************************************************************************
%* *
\subsection{Errors}
%************************************************************************
\begin{code}
+qualImportItemErr :: RdrName -> SDoc
+qualImportItemErr rdr
+ = hang (ptext (sLit "Illegal qualified name in import item:"))
+ 2 (ppr rdr)
+
badImportItemErr :: ModIface -> ImpDeclSpec -> IE RdrName -> SDoc
badImportItemErr iface decl_spec ie
= sep [ptext (sLit "Module"), quotes (ppr (is_mod decl_spec)), source_import,
nullModuleExport mod
= ptext (sLit "The export item `module") <+> ppr mod <> ptext (sLit "' exports nothing")
+missingImportListWarn :: ModuleName -> SDoc
+missingImportListWarn mod
+ = ptext (sLit "The module") <+> quotes (ppr mod) <+> ptext (sLit "does not have an explicit import list")
+
moduleWarn :: ModuleName -> WarningTxt -> SDoc
moduleWarn mod (WarningTxt txt)
= sep [ ptext (sLit "Module") <+> quotes (ppr mod) <> ptext (sLit ":"),
- nest 4 (ppr txt) ]
+ nest 2 (vcat (map ppr txt)) ]
moduleWarn mod (DeprecatedTxt txt)
= sep [ ptext (sLit "Module") <+> quotes (ppr mod)
<+> ptext (sLit "is deprecated:"),
- nest 4 (ppr txt) ]
+ nest 2 (vcat (map ppr txt)) ]
implicitPreludeWarn :: SDoc
implicitPreludeWarn
projects / ghc-hetmet.git / blobdiff