2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[RnNames]{Extracting imported and top-level names in scope}
8 rnImports, importsFromLocalDecls,
10 getLocalDeclBinders, extendRdrEnvRn,
11 reportUnusedNames, reportDeprecations
14 #include "HsVersions.h"
16 import DynFlags ( DynFlag(..), GhcMode(..), DynFlags(..) )
17 import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl,
18 ForeignDecl(..), HsGroup(..), HsValBinds(..),
19 Sig(..), collectHsBindLocatedBinders, tyClDeclNames,
20 instDeclATs, isIdxTyDecl,
23 import RnHsDoc ( rnHsDoc )
24 import IfaceEnv ( ifaceExportNames )
25 import LoadIface ( loadSrcInterface )
26 import TcRnMonad hiding (LIE)
33 import OccName ( srcDataName, pprNonVarNameSpace,
35 OccEnv, mkOccEnv, mkOccEnv_C, lookupOccEnv,
36 emptyOccEnv, extendOccEnv )
37 import HscTypes ( GenAvailInfo(..), AvailInfo, availNames, availName,
38 HomePackageTable, PackageIfaceTable,
39 mkPrintUnqualified, availsToNameSet,
40 Deprecs(..), ModIface(..), Dependencies(..),
41 lookupIfaceByModule, ExternalPackageState(..)
43 import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, Parent(..),
44 GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
45 emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts,
46 extendGlobalRdrEnv, lookupGlobalRdrEnv,
47 lookupGRE_RdrName, lookupGRE_Name,
48 Provenance(..), ImportSpec(..), ImpDeclSpec(..), ImpItemSpec(..),
49 importSpecLoc, importSpecModule, isLocalGRE, pprNameProvenance,
50 unQualSpecOK, qualSpecOK )
53 import SrcLoc ( Located(..), mkGeneralSrcSpan, getLoc,
54 unLoc, noLoc, srcLocSpan, SrcSpan )
57 import BasicTypes ( DeprecTxt )
58 import DriverPhases ( isHsBoot )
61 import Data.List ( partition, concatMap, (\\), delete )
62 import IO ( openFile, IOMode(..) )
68 %************************************************************************
72 %************************************************************************
75 rnImports :: [LImportDecl RdrName]
76 -> RnM ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
79 -- PROCESS IMPORT DECLS
80 -- Do the non {- SOURCE -} ones first, so that we get a helpful
81 -- warning for {- SOURCE -} ones that are unnecessary
82 = do this_mod <- getModule
83 implicit_prelude <- doptM Opt_ImplicitPrelude
84 let all_imports = mk_prel_imports this_mod implicit_prelude ++ imports
85 (source, ordinary) = partition is_source_import all_imports
86 is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
88 stuff1 <- mapM (rnImportDecl this_mod) ordinary
89 stuff2 <- mapM (rnImportDecl this_mod) source
90 let (decls, rdr_env, imp_avails) = combine (stuff1 ++ stuff2)
91 return (decls, rdr_env, imp_avails)
94 -- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();
95 -- because the former doesn't even look at Prelude.hi for instance
96 -- declarations, whereas the latter does.
97 mk_prel_imports this_mod implicit_prelude
99 || explicit_prelude_import
100 || not implicit_prelude
102 | otherwise = [preludeImportDecl]
103 explicit_prelude_import
104 = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports,
105 unLoc mod == pRELUDE_NAME ]
107 combine :: [(LImportDecl Name, GlobalRdrEnv, ImportAvails)]
108 -> ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
109 combine = foldr plus ([], emptyGlobalRdrEnv, emptyImportAvails)
110 where plus (decl, gbl_env1, imp_avails1)
111 (decls, gbl_env2, imp_avails2)
113 gbl_env1 `plusGlobalRdrEnv` gbl_env2,
114 imp_avails1 `plusImportAvails` imp_avails2)
116 preludeImportDecl :: LImportDecl RdrName
119 ImportDecl (L loc pRELUDE_NAME)
120 False {- Not a boot interface -}
121 False {- Not qualified -}
122 Nothing {- No "as" -}
123 Nothing {- No import list -}
125 loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
129 rnImportDecl :: Module
130 -> LImportDecl RdrName
131 -> RnM (LImportDecl Name, GlobalRdrEnv, ImportAvails)
133 rnImportDecl this_mod (L loc (ImportDecl loc_imp_mod_name want_boot
134 qual_only as_mod imp_details))
138 -- If there's an error in loadInterface, (e.g. interface
139 -- file not found) we get lots of spurious errors from 'filterImports'
141 imp_mod_name = unLoc loc_imp_mod_name
142 doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
144 iface <- loadSrcInterface doc imp_mod_name want_boot
146 -- Compiler sanity check: if the import didn't say
147 -- {-# SOURCE #-} we should not get a hi-boot file
148 WARN( not want_boot && mi_boot iface, ppr imp_mod_name ) (do
150 -- Issue a user warning for a redundant {- SOURCE -} import
151 -- NB that we arrange to read all the ordinary imports before
152 -- any of the {- SOURCE -} imports
153 warnIf (want_boot && not (mi_boot iface))
154 (warnRedundantSourceImport imp_mod_name)
157 imp_mod = mi_module iface
158 deprecs = mi_deprecs iface
159 is_orph = mi_orphan iface
160 has_finsts = mi_finsts iface
163 filtered_exports = filter not_this_mod (mi_exports iface)
164 not_this_mod (mod,_) = mod /= this_mod
165 -- If the module exports anything defined in this module, just
166 -- ignore it. Reason: otherwise it looks as if there are two
167 -- local definition sites for the thing, and an error gets
168 -- reported. Easiest thing is just to filter them out up
169 -- front. This situation only arises if a module imports
170 -- itself, or another module that imported it. (Necessarily,
171 -- this invoves a loop.)
173 -- Tiresome consequence: if you say
178 -- module B( AType ) where
179 -- import {-# SOURCE #-} A( AType )
181 -- then you'll get a 'B does not export AType' message. Oh well.
183 qual_mod_name = case as_mod of
184 Nothing -> imp_mod_name
185 Just another_name -> another_name
186 imp_spec = ImpDeclSpec { is_mod = imp_mod_name, is_qual = qual_only,
187 is_dloc = loc, is_as = qual_mod_name }
190 -- Get the total exports from this module
191 total_avails <- ifaceExportNames filtered_exports
193 -- filter the imports according to the import declaration
194 (new_imp_details, gbl_env) <-
195 filterImports iface imp_spec imp_details total_avails
200 -- Compute new transitive dependencies
202 orphans | is_orph = ASSERT( not (imp_mod `elem` dep_orphs deps) )
203 imp_mod : dep_orphs deps
204 | otherwise = dep_orphs deps
206 finsts | has_finsts = ASSERT( not (imp_mod `elem` dep_finsts deps) )
207 imp_mod : dep_finsts deps
208 | otherwise = dep_finsts deps
210 pkg = modulePackageId (mi_module iface)
212 (dependent_mods, dependent_pkgs)
213 | pkg == thisPackage dflags =
214 -- Imported module is from the home package
215 -- Take its dependent modules and add imp_mod itself
216 -- Take its dependent packages unchanged
218 -- NB: (dep_mods deps) might include a hi-boot file
219 -- for the module being compiled, CM. Do *not* filter
220 -- this out (as we used to), because when we've
221 -- finished dealing with the direct imports we want to
222 -- know if any of them depended on CM.hi-boot, in
223 -- which case we should do the hi-boot consistency
224 -- check. See LoadIface.loadHiBootInterface
225 ((imp_mod_name, want_boot) : dep_mods deps, dep_pkgs deps)
228 -- Imported module is from another package
229 -- Dump the dependent modules
230 -- Add the package imp_mod comes from to the dependent packages
231 ASSERT2( not (pkg `elem` dep_pkgs deps), ppr pkg <+> ppr (dep_pkgs deps) )
232 ([], pkg : dep_pkgs deps)
234 -- True <=> import M ()
235 import_all = case imp_details of
236 Just (is_hiding, ls) -> not is_hiding && null ls
239 imports = ImportAvails {
240 imp_mods = unitModuleEnv imp_mod (imp_mod, import_all, loc),
243 imp_dep_mods = mkModDeps dependent_mods,
244 imp_dep_pkgs = dependent_pkgs
247 -- Complain if we import a deprecated module
248 ifOptM Opt_WarnDeprecations (
250 DeprecAll txt -> addWarn (moduleDeprec imp_mod_name txt)
254 let new_imp_decl = L loc (ImportDecl loc_imp_mod_name want_boot
255 qual_only as_mod new_imp_details)
257 returnM (new_imp_decl, gbl_env, imports)
260 warnRedundantSourceImport mod_name
261 = ptext SLIT("Unnecessary {-# SOURCE #-} in the import of module")
262 <+> quotes (ppr mod_name)
266 %************************************************************************
268 importsFromLocalDecls
270 %************************************************************************
272 From the top-level declarations of this module produce
273 * the lexical environment
275 created by its bindings.
277 Complain about duplicate bindings
280 importsFromLocalDecls :: HsGroup RdrName -> RnM TcGblEnv
281 importsFromLocalDecls group
282 = do { gbl_env <- getGblEnv
284 ; avails <- getLocalDeclBinders gbl_env group
286 ; rdr_env' <- extendRdrEnvRn (tcg_rdr_env gbl_env) avails
288 ; traceRn (text "local avails: " <> ppr avails)
290 ; returnM (gbl_env { tcg_rdr_env = rdr_env' })
293 extendRdrEnvRn :: GlobalRdrEnv -> [AvailInfo] -> RnM GlobalRdrEnv
294 -- Add the new locally-bound names one by one, checking for duplicates as
295 -- we do so. Remember that in Template Haskell the duplicates
296 -- might *already be* in the GlobalRdrEnv from higher up the module
297 extendRdrEnvRn rdr_env avails
298 = foldlM add_local rdr_env (gresFromAvails LocalDef avails)
300 add_local rdr_env gre
301 | gres <- lookupGlobalRdrEnv rdr_env (nameOccName (gre_name gre))
302 , (dup_gre:_) <- filter isLocalGRE gres -- Check for existing *local* defns
303 = do { addDupDeclErr (gre_name dup_gre) (gre_name gre)
306 = return (extendGlobalRdrEnv rdr_env gre)
309 @getLocalDeclBinders@ returns the names for an @HsDecl@. It's
310 used for source code.
312 *** See "THE NAMING STORY" in HsDecls ****
314 Instances of indexed types
315 ~~~~~~~~~~~~~~~~~~~~~~~~~~
316 Indexed data/newtype instances contain data constructors that we need to
317 collect, too. Moreover, we need to descend into the data/newtypes instances
318 of associated families.
320 We need to be careful with the handling of the type constructor of each type
321 instance as the family constructor is already defined, and we want to avoid
322 raising a duplicate declaration error. So, we make a new name for it, but
323 don't return it in the 'AvailInfo'.
326 getLocalDeclBinders :: TcGblEnv -> HsGroup RdrName -> RnM [AvailInfo]
327 getLocalDeclBinders gbl_env (HsGroup {hs_valds = ValBindsIn val_decls val_sigs,
328 hs_tyclds = tycl_decls,
329 hs_instds = inst_decls,
330 hs_fords = foreign_decls })
331 = do { tc_names_s <- mappM new_tc tycl_decls
332 ; at_names_s <- mappM inst_ats inst_decls
333 ; val_names <- mappM new_simple val_bndrs
334 ; return (val_names ++ tc_names_s ++ concat at_names_s) }
336 mod = tcg_mod gbl_env
337 is_hs_boot = isHsBoot (tcg_src gbl_env) ;
338 val_bndrs | is_hs_boot = sig_hs_bndrs
339 | otherwise = for_hs_bndrs ++ val_hs_bndrs
340 -- In a hs-boot file, the value binders come from the
341 -- *signatures*, and there should be no foreign binders
343 new_simple rdr_name = do
344 nm <- newTopSrcBinder mod rdr_name
347 sig_hs_bndrs = [nm | L _ (TypeSig nm _) <- val_sigs]
348 val_hs_bndrs = collectHsBindLocatedBinders val_decls
349 for_hs_bndrs = [nm | L _ (ForeignImport nm _ _) <- foreign_decls]
352 | isIdxTyDecl (unLoc tc_decl)
353 = do { main_name <- lookupFamInstDeclBndr mod main_rdr
354 ; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
355 ; return (AvailTC main_name sub_names) }
356 -- main_name is not bound here!
358 = do { main_name <- newTopSrcBinder mod main_rdr
359 ; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
360 ; return (AvailTC main_name (main_name : sub_names)) }
362 (main_rdr : sub_rdrs) = tyClDeclNames (unLoc tc_decl)
365 = mappM new_tc (instDeclATs (unLoc inst_decl))
367 getLocalDeclBinders _ _ = panic "getLocalDeclBinders" -- ValBindsOut can't happen
371 %************************************************************************
373 \subsection{Filtering imports}
375 %************************************************************************
377 @filterImports@ takes the @ExportEnv@ telling what the imported module makes
378 available, and filters it through the import spec (if any).
381 filterImports :: ModIface
382 -> ImpDeclSpec -- The span for the entire import decl
383 -> Maybe (Bool, [LIE RdrName]) -- Import spec; True => hiding
384 -> [AvailInfo] -- What's available
385 -> RnM (Maybe (Bool, [LIE Name]), -- Import spec w/ Names
386 GlobalRdrEnv) -- Same again, but in GRE form
388 filterImports iface decl_spec Nothing all_avails
389 = return (Nothing, mkGlobalRdrEnv (gresFromAvails prov all_avails))
391 prov = Imported [ImpSpec { is_decl = decl_spec, is_item = ImpAll }]
394 filterImports iface decl_spec (Just (want_hiding, import_items)) all_avails
395 = do -- check for errors, convert RdrNames to Names
396 opt_indexedtypes <- doptM Opt_IndexedTypes
397 items1 <- mapM (lookup_lie opt_indexedtypes) import_items
399 let items2 :: [(LIE Name, AvailInfo)]
400 items2 = concat items1
401 -- NB the AvailInfo may have duplicates, and several items
402 -- for the same parent; e.g N(x) and N(y)
404 names = availsToNameSet (map snd items2)
405 keep n = not (n `elemNameSet` names)
406 pruned_avails = filterAvails keep all_avails
407 hiding_prov = Imported [ImpSpec { is_decl = decl_spec, is_item = ImpAll }]
409 gres | want_hiding = gresFromAvails hiding_prov pruned_avails
410 | otherwise = concatMap (gresFromIE decl_spec) items2
412 return (Just (want_hiding, map fst items2), mkGlobalRdrEnv gres)
414 -- This environment is how we map names mentioned in the import
415 -- list to the actual Name they correspond to, and the name family
416 -- that the Name belongs to (the AvailInfo). The situation is
417 -- complicated by associated families, which introduce a three-level
418 -- hierachy, where class = grand parent, assoc family = parent, and
419 -- data constructors = children. The occ_env entries for associated
420 -- families needs to capture all this information; hence, we have the
421 -- third component of the environment that gives the class name (=
422 -- grand parent) in case of associated families.
424 -- This env will have entries for data constructors too,
425 -- they won't make any difference because naked entities like T
426 -- in an import list map to TcOccs, not VarOccs.
427 occ_env :: OccEnv (Name, -- the name
428 AvailInfo, -- the export item providing the name
429 Maybe Name) -- the parent of associated types
430 occ_env = mkOccEnv_C combine [ (nameOccName n, (n, a, Nothing))
431 | a <- all_avails, n <- availNames a]
433 -- we know that (1) there are at most entries for one name, (2) their
434 -- first component is identical, (3) they are for tys/cls, and (4) one
435 -- entry has the name in its parent position (the other doesn't)
436 combine (name, AvailTC p1 subs1, Nothing)
437 (_ , AvailTC p2 subs2, Nothing)
439 (parent, subs) = if p1 == name then (p2, subs1) else (p1, subs2)
441 (name, AvailTC name subs, Just parent)
443 lookup_lie :: Bool -> LIE RdrName -> TcRn [(LIE Name, AvailInfo)]
444 lookup_lie opt_indexedtypes (L loc ieRdr)
446 stuff <- setSrcSpan loc $
447 case lookup_ie opt_indexedtypes ieRdr of
448 Failed err -> addErr err >> return []
449 Succeeded a -> return a
450 checkDodgyImport stuff
451 return [ (L loc ie, avail) | (ie,avail) <- stuff ]
453 -- Warn when importing T(..) if T was exported abstractly
454 checkDodgyImport stuff
455 | IEThingAll n <- ieRdr, (_, AvailTC _ [one]):_ <- stuff
456 = ifOptM Opt_WarnDodgyImports (addWarn (dodgyImportWarn n))
457 -- NB. use the RdrName for reporting the warning
461 -- For each import item, we convert its RdrNames to Names,
462 -- and at the same time construct an AvailInfo corresponding
463 -- to what is actually imported by this item.
464 -- Returns Nothing on error.
465 -- We return a list here, because in the case of an import
466 -- item like C, if we are hiding, then C refers to *both* a
467 -- type/class and a data constructor. Moreover, when we import
468 -- data constructors of an associated family, we need separate
469 -- AvailInfos for the data constructors and the family (as they have
470 -- different parents). See the discussion at occ_env.
471 lookup_ie :: Bool -> IE RdrName -> MaybeErr Message [(IE Name,AvailInfo)]
472 lookup_ie opt_indexedtypes ie
473 = let bad_ie = Failed (badImportItemErr iface decl_spec ie)
475 lookup_name rdrName =
476 case lookupOccEnv occ_env (rdrNameOcc rdrName) of
482 (name, avail, _) <- lookup_name n
483 return [(IEVar name, trimAvail avail name)]
486 (name, avail@(AvailTC name2 subs), mb_parent) <- lookup_name tc
488 -- non-associated ty/cls
489 Nothing -> return [(IEThingAll name, avail)]
491 Just parent -> return [(IEThingAll name,
492 AvailTC name2 (subs \\ [name])),
493 (IEThingAll name, AvailTC parent [name])]
496 | want_hiding -- hiding ( C )
497 -- Here the 'C' can be a data constructor
498 -- *or* a type/class, or even both
499 -> let tc_name = lookup_name tc
500 dc_name = lookup_name (setRdrNameSpace tc srcDataName)
502 case catMaybeErr [ tc_name, dc_name ] of
504 names -> return [mkIEThingAbs name | name <- names]
506 -> do nameAvail <- lookup_name tc
507 return [mkIEThingAbs nameAvail]
509 IEThingWith tc ns -> do
510 (name, AvailTC name2 subnames, mb_parent) <- lookup_name tc
512 env = mkOccEnv [(nameOccName s, s) | s <- subnames]
513 mb_children = map (lookupOccEnv env . rdrNameOcc) ns
514 children <- if any isNothing mb_children
516 else return (catMaybes mb_children)
517 -- check for proper import of indexed types
518 when (not opt_indexedtypes && any isTyConName children) $
519 Failed (typeItemErr (head . filter isTyConName $ children)
520 (text "in import list"))
522 -- non-associated ty/cls
523 Nothing -> return [(IEThingWith name children,
524 AvailTC name (name:children))]
526 Just parent -> return [(IEThingWith name children,
527 AvailTC name children),
528 (IEThingWith name children,
529 AvailTC parent [name])]
531 _other -> Failed illegalImportItemErr
532 -- could be IEModuleContents, IEGroup, IEDoc, IEDocNamed
536 mkIEThingAbs (n, av, Nothing ) = (IEThingAbs n, trimAvail av n)
537 mkIEThingAbs (n, av, Just parent) = (IEThingAbs n, AvailTC parent [n])
540 catMaybeErr :: [MaybeErr err a] -> [a]
541 catMaybeErr ms = [ a | Succeeded a <- ms ]
544 %************************************************************************
548 %************************************************************************
551 -- | make a 'GlobalRdrEnv' where all the elements point to the same
552 -- import declaration (useful for "hiding" imports, or imports with
554 gresFromAvails :: Provenance -> [AvailInfo] -> [GlobalRdrElt]
555 gresFromAvails prov avails
556 = concatMap (gresFromAvail (const prov)) avails
558 gresFromAvail :: (Name -> Provenance) -> AvailInfo -> [GlobalRdrElt]
559 gresFromAvail prov_fn avail
560 = [ GRE {gre_name = n,
561 gre_par = availParent n avail,
562 gre_prov = prov_fn n}
563 | n <- availNames avail ]
565 greAvail :: GlobalRdrElt -> AvailInfo
566 greAvail gre = mkUnitAvail (gre_name gre) (gre_par gre)
568 mkUnitAvail :: Name -> Parent -> AvailInfo
569 mkUnitAvail me (ParentIs p) = AvailTC p [me]
570 mkUnitAvail me NoParent | isTyConName me = AvailTC me [me]
571 | otherwise = Avail me
573 plusAvail (Avail n1) (Avail n2) = Avail n1
574 plusAvail (AvailTC n1 ns1) (AvailTC n2 ns2) = AvailTC n2 (ns1 `unionLists` ns2)
575 plusAvail a1 a2 = pprPanic "RnEnv.plusAvail" (hsep [ppr a1,ppr a2])
577 availParent :: Name -> AvailInfo -> Parent
578 availParent n (Avail _) = NoParent
579 availParent n (AvailTC m ms) | n==m = NoParent
580 | otherwise = ParentIs m
582 trimAvail :: AvailInfo -> Name -> AvailInfo
583 trimAvail (Avail n) m = Avail n
584 trimAvail (AvailTC n ns) m = ASSERT( m `elem` ns) AvailTC n [m]
586 -- | filters 'AvailInfo's by the given predicate
587 filterAvails :: (Name -> Bool) -> [AvailInfo] -> [AvailInfo]
588 filterAvails keep avails = foldr (filterAvail keep) [] avails
590 -- | filters an 'AvailInfo' by the given predicate
591 filterAvail :: (Name -> Bool) -> AvailInfo -> [AvailInfo] -> [AvailInfo]
592 filterAvail keep ie rest =
594 Avail n | keep n -> ie : rest
597 let left = filter keep ns in
598 if null left then rest else AvailTC tc left : rest
600 -- | Given an import/export spec, construct the appropriate 'GlobalRdrElt's.
601 gresFromIE :: ImpDeclSpec -> (LIE Name, AvailInfo) -> [GlobalRdrElt]
602 gresFromIE decl_spec (L loc ie, avail)
603 = gresFromAvail prov_fn avail
605 is_explicit = case ie of
606 IEThingAll name -> \n -> n==name
608 prov_fn name = Imported [imp_spec]
610 imp_spec = ImpSpec { is_decl = decl_spec, is_item = item_spec }
611 item_spec = ImpSome { is_explicit = is_explicit name, is_iloc = loc }
613 mkChildEnv :: [GlobalRdrElt] -> NameEnv [Name]
614 mkChildEnv gres = foldr add emptyNameEnv gres
616 add (GRE { gre_name = n, gre_par = ParentIs p }) env = extendNameEnv_C (++) env p [n]
617 add other_gre env = env
619 findChildren :: NameEnv [Name] -> Name -> [Name]
620 findChildren env n = lookupNameEnv env n `orElse` []
623 ---------------------------------------
626 All this AvailEnv stuff is hardly used; only in a very small
627 part of RnNames. Todo: remove?
628 ---------------------------------------
631 type AvailEnv = NameEnv AvailInfo -- Maps a Name to the AvailInfo that contains it
633 emptyAvailEnv :: AvailEnv
634 emptyAvailEnv = emptyNameEnv
636 unitAvailEnv :: AvailInfo -> AvailEnv
637 unitAvailEnv a = unitNameEnv (availName a) a
639 plusAvailEnv :: AvailEnv -> AvailEnv -> AvailEnv
640 plusAvailEnv = plusNameEnv_C plusAvail
642 availEnvElts :: AvailEnv -> [AvailInfo]
643 availEnvElts = nameEnvElts
645 addAvail :: AvailEnv -> AvailInfo -> AvailEnv
646 addAvail avails avail = extendNameEnv_C plusAvail avails (availName avail) avail
648 mkAvailEnv :: [AvailInfo] -> AvailEnv
649 -- 'avails' may have several items with the same availName
650 -- E.g import Ix( Ix(..), index )
651 -- will give Ix(Ix,index,range) and Ix(index)
652 -- We want to combine these; addAvail does that
653 mkAvailEnv avails = foldl addAvail emptyAvailEnv avails
655 -- After combining the avails, we need to ensure that the parent name is the
656 -- first entry in the list of subnames, if it is included at all. (Subsequent
657 -- functions rely on that.)
658 normaliseAvail :: AvailInfo -> AvailInfo
659 normaliseAvail avail@(Avail _) = avail
660 normaliseAvail (AvailTC name subs) = AvailTC name subs'
662 subs' = if name `elem` subs then name : (delete name subs) else subs
664 -- | combines 'AvailInfo's from the same family
665 nubAvails :: [AvailInfo] -> [AvailInfo]
666 nubAvails avails = map normaliseAvail . nameEnvElts . mkAvailEnv $ avails
670 %************************************************************************
672 \subsection{Export list processing}
674 %************************************************************************
676 Processing the export list.
678 You might think that we should record things that appear in the export
679 list as ``occurrences'' (using @addOccurrenceName@), but you'd be
680 wrong. We do check (here) that they are in scope, but there is no
681 need to slurp in their actual declaration (which is what
682 @addOccurrenceName@ forces).
684 Indeed, doing so would big trouble when compiling @PrelBase@, because
685 it re-exports @GHC@, which includes @takeMVar#@, whose type includes
686 @ConcBase.StateAndSynchVar#@, and so on...
689 type ExportAccum -- The type of the accumulating parameter of
690 -- the main worker function in rnExports
691 = ([LIE Name], -- Export items with Names
692 ExportOccMap, -- Tracks exported occurrence names
693 [AvailInfo]) -- The accumulated exported stuff
696 emptyExportAccum = ([], emptyOccEnv, [])
698 type ExportOccMap = OccEnv (Name, IE RdrName)
699 -- Tracks what a particular exported OccName
700 -- in an export list refers to, and which item
701 -- it came from. It's illegal to export two distinct things
702 -- that have the same occurrence name
704 rnExports :: Bool -- False => no 'module M(..) where' header at all
705 -> Maybe [LIE RdrName] -- Nothing => no explicit export list
706 -> RnM (Maybe [LIE Name], [AvailInfo])
708 -- Complains if two distinct exports have same OccName
709 -- Warns about identical exports.
710 -- Complains about exports items not in scope
712 rnExports explicit_mod exports
713 = do TcGblEnv { tcg_mod = this_mod,
714 tcg_rdr_env = rdr_env,
715 tcg_imports = imports } <- getGblEnv
717 -- If the module header is omitted altogether, then behave
718 -- as if the user had written "module Main(main) where..."
719 -- EXCEPT in interactive mode, when we behave as if he had
720 -- written "module Main where ..."
721 -- Reason: don't want to complain about 'main' not in scope
722 -- in interactive mode
723 ghc_mode <- getGhcMode
728 | ghc_mode == Interactive
731 -> do mainName <- lookupGlobalOccRn main_RDR_Unqual
732 return (Just ([noLoc (IEVar main_RDR_Unqual)]))
733 -- ToDo: the 'noLoc' here is unhelpful if 'main' turns
734 -- out to be out of scope
736 (exp_spec, avails) <- exports_from_avail real_exports rdr_env imports this_mod
738 return (exp_spec, nubAvails avails) -- Combine families
740 exports_from_avail :: Maybe [LIE RdrName]
741 -- Nothing => no explicit export list
745 -> RnM (Maybe [LIE Name], [AvailInfo])
747 exports_from_avail Nothing rdr_env imports this_mod
748 = -- The same as (module M) where M is the current module name,
749 -- so that's how we handle it.
751 avails = [ greAvail gre | gre <- globalRdrEnvElts rdr_env,
754 return (Nothing, avails)
756 exports_from_avail (Just rdr_items) rdr_env imports this_mod
757 = do (ie_names, _, exports) <- foldlM do_litem emptyExportAccum rdr_items
759 return (Just ie_names, exports)
761 do_litem :: ExportAccum -> LIE RdrName -> RnM ExportAccum
762 do_litem acc lie = setSrcSpan (getLoc lie) (exports_from_item acc lie)
764 kids_env :: NameEnv [Name] -- Maps a parent to its in-scope children
765 kids_env = mkChildEnv (globalRdrEnvElts rdr_env)
767 exports_from_item :: ExportAccum -> LIE RdrName -> RnM ExportAccum
768 exports_from_item acc@(ie_names, occs, exports)
769 (L loc ie@(IEModuleContents mod))
770 | let earlier_mods = [ mod | (L _ (IEModuleContents mod)) <- ie_names ]
771 , mod `elem` earlier_mods -- Duplicate export of M
772 = do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
773 warnIf warn_dup_exports (dupModuleExport mod) ;
777 = do { implicit_prelude <- doptM Opt_ImplicitPrelude
778 ; let gres = filter (isModuleExported implicit_prelude mod)
779 (globalRdrEnvElts rdr_env)
781 ; warnIf (null gres) (nullModuleExport mod)
783 ; occs' <- check_occs ie occs (map gre_name gres)
784 -- This check_occs not only finds conflicts
785 -- between this item and others, but also
786 -- internally within this item. That is, if
787 -- 'M.x' is in scope in several ways, we'll have
788 -- several members of mod_avails with the same
790 ; return (L loc (IEModuleContents mod) : ie_names,
791 occs', map greAvail gres ++ exports) }
793 exports_from_item acc@(lie_names, occs, exports) (L loc ie)
795 = do new_ie <- lookup_doc_ie ie
796 return (L loc new_ie : lie_names, occs, exports)
799 = do (new_ie, avail) <- lookup_ie ie
800 if isUnboundName (ieName new_ie)
801 then return acc -- Avoid error cascade
804 occs' <- check_occs ie occs (availNames avail)
806 return (L loc new_ie : lie_names, occs', avail : exports)
809 lookup_ie :: IE RdrName -> RnM (IE Name, AvailInfo)
810 lookup_ie (IEVar rdr)
811 = do gre <- lookupGreRn rdr
812 return (IEVar (gre_name gre), greAvail gre)
814 lookup_ie (IEThingAbs rdr)
815 = do name <- lookupGlobalOccRn rdr
816 case lookupGRE_RdrName rdr rdr_env of
817 [] -> panic "RnNames.lookup_ie"
818 elt:_ -> case gre_par elt of
819 NoParent -> return (IEThingAbs name,
821 ParentIs p -> return (IEThingAbs name,
824 lookup_ie ie@(IEThingAll rdr)
825 = do name <- lookupGlobalOccRn rdr
826 let kids = findChildren kids_env name
828 (if (isTyConName name) then addWarn (dodgyExportWarn name)
829 -- This occurs when you export T(..), but
830 -- only import T abstractly, or T is a synonym.
831 else addErr (exportItemErr ie))
833 return (IEThingAll name, AvailTC name (name:kids))
835 lookup_ie ie@(IEThingWith rdr sub_rdrs)
836 = do name <- lookupGlobalOccRn rdr
837 if isUnboundName name
838 then return (IEThingWith name [], AvailTC name [name])
840 let env = mkOccEnv [ (nameOccName s, s)
841 | s <- findChildren kids_env name ]
842 mb_names = map (lookupOccEnv env . rdrNameOcc) sub_rdrs
843 if any isNothing mb_names
844 then do addErr (exportItemErr ie)
845 return (IEThingWith name [], AvailTC name [name])
846 else do let names = catMaybes mb_names
847 optIdxTypes <- doptM Opt_IndexedTypes
848 when (not optIdxTypes && any isTyConName names) $
849 addErr (typeItemErr ( head
852 (text "in export list"))
853 return (IEThingWith name names, AvailTC name (name:names))
855 lookup_ie ie = panic "lookup_ie" -- Other cases covered earlier
858 lookup_doc_ie :: IE RdrName -> RnM (IE Name)
859 lookup_doc_ie (IEGroup lev doc) = do rn_doc <- rnHsDoc doc
860 return (IEGroup lev rn_doc)
861 lookup_doc_ie (IEDoc doc) = do rn_doc <- rnHsDoc doc
862 return (IEDoc rn_doc)
863 lookup_doc_ie (IEDocNamed str) = return (IEDocNamed str)
864 lookup_doc_ie ie = panic "lookup_doc_ie" -- Other cases covered earlier
867 isDoc (IEDoc _) = True
868 isDoc (IEDocNamed _) = True
869 isDoc (IEGroup _ _) = True
872 -------------------------------
873 isModuleExported :: Bool -> ModuleName -> GlobalRdrElt -> Bool
874 -- True if the thing is in scope *both* unqualified, *and* with qualifier M
875 isModuleExported implicit_prelude mod (GRE { gre_name = name, gre_prov = prov })
876 | implicit_prelude && isBuiltInSyntax name = False
877 -- Optimisation: filter out names for built-in syntax
878 -- They just clutter up the environment (esp tuples), and the parser
879 -- will generate Exact RdrNames for them, so the cluttered
880 -- envt is no use. To avoid doing this filter all the time,
881 -- we use -fno-implicit-prelude as a clue that the filter is
882 -- worth while. Really, it's only useful for GHC.Base and GHC.Tuple.
884 -- It's worth doing because it makes the environment smaller for
885 -- every module that imports the Prelude
888 LocalDef -> moduleName (nameModule name) == mod
889 Imported is -> any unQualSpecOK is && any (qualSpecOK mod) is
891 -------------------------------
892 check_occs :: IE RdrName -> ExportOccMap -> [Name] -> RnM ExportOccMap
893 check_occs ie occs names
894 = foldlM check occs names
897 = case lookupOccEnv occs name_occ of
898 Nothing -> returnM (extendOccEnv occs name_occ (name, ie))
901 | name == name' -- Duplicate export
902 -> do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
903 warnIf warn_dup_exports (dupExportWarn name_occ ie ie') ;
906 | otherwise -- Same occ name but different names: an error
907 -> do { global_env <- getGlobalRdrEnv ;
908 addErr (exportClashErr global_env name' name ie' ie) ;
911 name_occ = nameOccName name
914 %*********************************************************
918 %*********************************************************
921 reportDeprecations :: DynFlags -> TcGblEnv -> RnM ()
922 reportDeprecations dflags tcg_env
923 = ifOptM Opt_WarnDeprecations $
924 do { (eps,hpt) <- getEpsAndHpt
925 -- By this time, typechecking is complete,
926 -- so the PIT is fully populated
927 ; mapM_ (check hpt (eps_PIT eps)) all_gres }
929 used_names = allUses (tcg_dus tcg_env)
930 -- Report on all deprecated uses; hence allUses
931 all_gres = globalRdrEnvElts (tcg_rdr_env tcg_env)
933 check hpt pit gre@(GRE {gre_name = name, gre_prov = Imported (imp_spec:_)})
934 | name `elemNameSet` used_names
935 , Just deprec_txt <- lookupDeprec dflags hpt pit gre
936 = addWarnAt (importSpecLoc imp_spec)
937 (sep [ptext SLIT("Deprecated use of") <+>
938 pprNonVarNameSpace (occNameSpace (nameOccName name)) <+>
940 (parens imp_msg) <> colon,
943 name_mod = nameModule name
944 imp_mod = importSpecModule imp_spec
945 imp_msg = ptext SLIT("imported from") <+> ppr imp_mod <> extra
946 extra | imp_mod == moduleName name_mod = empty
947 | otherwise = ptext SLIT(", but defined in") <+> ppr name_mod
949 check hpt pit ok_gre = returnM () -- Local, or not used, or not deprectated
950 -- The Imported pattern-match: don't deprecate locally defined names
951 -- For a start, we may be exporting a deprecated thing
952 -- Also we may use a deprecated thing in the defn of another
953 -- deprecated things. We may even use a deprecated thing in
954 -- the defn of a non-deprecated thing, when changing a module's
957 lookupDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
958 -> GlobalRdrElt -> Maybe DeprecTxt
959 lookupDeprec dflags hpt pit gre
960 = case lookupIfaceByModule dflags hpt pit (nameModule name) of
961 Just iface -> mi_dep_fn iface name `seqMaybe` -- Bleat if the thing, *or
963 ParentIs p -> mi_dep_fn iface p -- its parent*, is deprec'd
966 | isWiredInName name -> Nothing
967 -- We have not necessarily loaded the .hi file for a
968 -- wired-in name (yet), although we *could*.
969 -- And we never deprecate them
971 | otherwise -> pprPanic "lookupDeprec" (ppr name)
972 -- By now all the interfaces should have been loaded
977 %*********************************************************
981 %*********************************************************
984 reportUnusedNames :: Maybe [LIE RdrName] -- Export list
985 -> TcGblEnv -> RnM ()
986 reportUnusedNames export_decls gbl_env
987 = do { traceRn ((text "RUN") <+> (ppr (tcg_dus gbl_env)))
988 ; warnUnusedTopBinds unused_locals
989 ; warnUnusedModules unused_imp_mods
990 ; warnUnusedImports unused_imports
991 ; warnDuplicateImports defined_and_used
992 ; printMinimalImports minimal_imports }
994 used_names :: NameSet
995 used_names = findUses (tcg_dus gbl_env) emptyNameSet
996 -- NB: currently, if f x = g, we only treat 'g' as used if 'f' is used
999 -- Collect the defined names from the in-scope environment
1000 defined_names :: [GlobalRdrElt]
1001 defined_names = globalRdrEnvElts (tcg_rdr_env gbl_env)
1003 -- Note that defined_and_used, defined_but_not_used
1004 -- are both [GRE]; that's why we need defined_and_used
1005 -- rather than just used_names
1006 defined_and_used, defined_but_not_used :: [GlobalRdrElt]
1007 (defined_and_used, defined_but_not_used)
1008 = partition (gre_is_used used_names) defined_names
1010 kids_env = mkChildEnv defined_names
1011 -- This is done in mkExports too; duplicated work
1013 gre_is_used :: NameSet -> GlobalRdrElt -> Bool
1014 gre_is_used used_names (GRE {gre_name = name})
1015 = name `elemNameSet` used_names
1016 || any (`elemNameSet` used_names) (findChildren kids_env name)
1017 -- A use of C implies a use of T,
1018 -- if C was brought into scope by T(..) or T(C)
1020 -- Filter out the ones that are
1021 -- (a) defined in this module, and
1022 -- (b) not defined by a 'deriving' clause
1023 -- The latter have an Internal Name, so we can filter them out easily
1024 unused_locals :: [GlobalRdrElt]
1025 unused_locals = filter is_unused_local defined_but_not_used
1026 is_unused_local :: GlobalRdrElt -> Bool
1027 is_unused_local gre = isLocalGRE gre && isExternalName (gre_name gre)
1029 unused_imports :: [GlobalRdrElt]
1030 unused_imports = filter unused_imp defined_but_not_used
1031 unused_imp (GRE {gre_prov = Imported imp_specs})
1032 = not (all (module_unused . importSpecModule) imp_specs)
1033 && or [exp | ImpSpec { is_item = ImpSome { is_explicit = exp } } <- imp_specs]
1034 -- Don't complain about unused imports if we've already said the
1035 -- entire import is unused
1036 unused_imp other = False
1038 -- To figure out the minimal set of imports, start with the things
1039 -- that are in scope (i.e. in gbl_env). Then just combine them
1040 -- into a bunch of avails, so they are properly grouped
1042 -- BUG WARNING: this does not deal properly with qualified imports!
1043 minimal_imports :: FiniteMap ModuleName AvailEnv
1044 minimal_imports0 = foldr add_expall emptyFM expall_mods
1045 minimal_imports1 = foldr add_name minimal_imports0 defined_and_used
1046 minimal_imports = foldr add_inst_mod minimal_imports1 direct_import_mods
1047 -- The last line makes sure that we retain all direct imports
1048 -- even if we import nothing explicitly.
1049 -- It's not necessarily redundant to import such modules. Consider
1053 -- The import M() is not *necessarily* redundant, even if
1054 -- we suck in no instance decls from M (e.g. it contains
1055 -- no instance decls, or This contains no code). It may be
1056 -- that we import M solely to ensure that M's orphan instance
1057 -- decls (or those in its imports) are visible to people who
1058 -- import This. Sigh.
1059 -- There's really no good way to detect this, so the error message
1060 -- in RnEnv.warnUnusedModules is weakened instead
1062 -- We've carefully preserved the provenance so that we can
1063 -- construct minimal imports that import the name by (one of)
1064 -- the same route(s) as the programmer originally did.
1065 add_name gre@(GRE {gre_prov = Imported (imp_spec:_)}) acc
1066 = addToFM_C plusAvailEnv acc
1067 (importSpecModule imp_spec) (unitAvailEnv (greAvail gre))
1068 add_name gre acc = acc -- Local
1070 -- Modules mentioned as 'module M' in the export list
1071 expall_mods = case export_decls of
1073 Just es -> [m | L _ (IEModuleContents m) <- es]
1075 -- This is really bogus. The idea is that if we see 'module M' in
1076 -- the export list we must retain the import decls that drive it
1077 -- If we aren't careful we might see
1078 -- module A( module M ) where
1081 -- and suppose that N exports everything that M does. Then we
1082 -- must not drop the import of M even though N brings it all into
1085 -- BUG WARNING: 'module M' exports aside, what if M.x is mentioned?!
1087 -- The reason that add_expall is bogus is that it doesn't take
1088 -- qualified imports into account. But it's an improvement.
1089 add_expall mod acc = addToFM_C plusAvailEnv acc mod emptyAvailEnv
1091 add_inst_mod (mod,_,_) acc
1092 | mod_name `elemFM` acc = acc -- We import something already
1093 | otherwise = addToFM acc mod_name emptyAvailEnv
1095 mod_name = moduleName mod
1096 -- Add an empty collection of imports for a module
1097 -- from which we have sucked only instance decls
1099 imports = tcg_imports gbl_env
1101 direct_import_mods :: [(Module, Bool, SrcSpan)]
1102 -- See the type of the imp_mods for this triple
1103 direct_import_mods = moduleEnvElts (imp_mods imports)
1105 -- unused_imp_mods are the directly-imported modules
1106 -- that are not mentioned in minimal_imports1
1107 -- [Note: not 'minimal_imports', because that includes directly-imported
1108 -- modules even if we use nothing from them; see notes above]
1110 -- BUG WARNING: does not deal correctly with multiple imports of the same module
1111 -- becuase direct_import_mods has only one entry per module
1112 unused_imp_mods = [(mod_name,loc) | (mod,no_imp,loc) <- direct_import_mods,
1113 let mod_name = moduleName mod,
1114 not (mod_name `elemFM` minimal_imports1),
1117 -- The not no_imp part is not to complain about
1118 -- import M (), which is an idiom for importing
1119 -- instance declarations
1121 module_unused :: ModuleName -> Bool
1122 module_unused mod = any (((==) mod) . fst) unused_imp_mods
1124 ---------------------
1125 warnDuplicateImports :: [GlobalRdrElt] -> RnM ()
1126 -- Given the GREs for names that are used, figure out which imports
1127 -- could be omitted without changing the top-level environment.
1129 -- NB: Given import Foo( T )
1130 -- import qualified Foo
1131 -- we do not report a duplicate import, even though Foo.T is brought
1132 -- into scope by both, because there's nothing you can *omit* without
1133 -- changing the top-level environment. So we complain only if it's
1134 -- explicitly named in both imports or neither.
1136 -- Furthermore, we complain about Foo.T only if
1137 -- there is no complaint about (unqualified) T
1139 warnDuplicateImports gres
1140 = ifOptM Opt_WarnUnusedImports $
1141 sequenceM_ [ warn name pr
1142 -- The 'head' picks the first offending group
1143 -- for this particular name
1144 | GRE { gre_name = name, gre_prov = Imported imps } <- gres
1145 , pr <- redundants imps ]
1147 warn name (red_imp, cov_imp)
1148 = addWarnAt (importSpecLoc red_imp)
1149 (vcat [ptext SLIT("Redundant import of:") <+> quotes pp_name,
1150 ptext SLIT("It is also") <+> ppr cov_imp])
1152 pp_name | is_qual red_decl = ppr (is_as red_decl) <> dot <> ppr occ
1153 | otherwise = ppr occ
1154 occ = nameOccName name
1155 red_decl = is_decl red_imp
1157 redundants :: [ImportSpec] -> [(ImportSpec,ImportSpec)]
1158 -- The returned pair is (redundant-import, covering-import)
1160 = [ (red_imp, cov_imp)
1162 , cov_imp <- take 1 (filter (covers red_imp) imps) ]
1164 -- "red_imp" is a putative redundant import
1165 -- "cov_imp" potentially covers it
1166 -- This test decides whether red_imp could be dropped
1168 -- NOTE: currently the test does not warn about
1171 -- even if the same underlying 'x' is involved, because dropping
1172 -- either import would change the qualified names in scope (M.x, N.x)
1173 -- But if the qualified names aren't used, the import is indeed redundant
1174 -- Sadly we don't know that. Oh well.
1175 covers red_imp@(ImpSpec { is_decl = red_decl, is_item = red_item })
1176 cov_imp@(ImpSpec { is_decl = cov_decl, is_item = cov_item })
1177 | red_loc == cov_loc
1178 = False -- Ignore diagonal elements
1179 | not (is_as red_decl == is_as cov_decl)
1180 = False -- They bring into scope different qualified names
1181 | not (is_qual red_decl) && is_qual cov_decl
1182 = False -- Covering one doesn't bring unqualified name into scope
1184 = not cov_selective -- Redundant one is selective and covering one isn't
1185 || red_later -- Both are explicit; tie-break using red_later
1187 = not cov_selective -- Neither import is selective
1188 && (is_mod red_decl == is_mod cov_decl) -- They import the same module
1189 && red_later -- Tie-break
1191 red_loc = importSpecLoc red_imp
1192 cov_loc = importSpecLoc cov_imp
1193 red_later = red_loc > cov_loc
1194 cov_selective = selectiveImpItem cov_item
1195 red_selective = selectiveImpItem red_item
1197 selectiveImpItem :: ImpItemSpec -> Bool
1198 selectiveImpItem ImpAll = False
1199 selectiveImpItem (ImpSome {}) = True
1201 -- ToDo: deal with original imports with 'qualified' and 'as M' clauses
1202 printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports
1204 printMinimalImports imps
1205 = ifOptM Opt_D_dump_minimal_imports $ do {
1207 mod_ies <- mappM to_ies (fmToList imps) ;
1208 this_mod <- getModule ;
1209 rdr_env <- getGlobalRdrEnv ;
1210 ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ;
1211 printForUser h (mkPrintUnqualified rdr_env)
1212 (vcat (map ppr_mod_ie mod_ies)) })
1215 mkFilename this_mod = moduleNameString (moduleName this_mod) ++ ".imports"
1216 ppr_mod_ie (mod_name, ies)
1217 | mod_name == moduleName pRELUDE
1219 | null ies -- Nothing except instances comes from here
1220 = ptext SLIT("import") <+> ppr mod_name <> ptext SLIT("() -- Instances only")
1222 = ptext SLIT("import") <+> ppr mod_name <>
1223 parens (fsep (punctuate comma (map ppr ies)))
1225 to_ies (mod, avail_env) = do ies <- mapM to_ie (availEnvElts avail_env)
1228 to_ie :: AvailInfo -> RnM (IE Name)
1229 -- The main trick here is that if we're importing all the constructors
1230 -- we want to say "T(..)", but if we're importing only a subset we want
1231 -- to say "T(A,B,C)". So we have to find out what the module exports.
1232 to_ie (Avail n) = returnM (IEVar n)
1233 to_ie (AvailTC n [m]) = ASSERT( n==m )
1234 returnM (IEThingAbs n)
1235 to_ie (AvailTC n ns)
1236 = loadSrcInterface doc n_mod False `thenM` \ iface ->
1237 case [xs | (m,as) <- mi_exports iface,
1238 moduleName m == n_mod,
1240 x == nameOccName n] of
1241 [xs] | all_used xs -> returnM (IEThingAll n)
1242 | otherwise -> returnM (IEThingWith n (filter (/= n) ns))
1243 other -> pprTrace "to_ie" (ppr n <+> ppr n_mod <+> ppr other) $
1246 all_used avail_occs = all (`elem` map nameOccName ns) avail_occs
1247 doc = text "Compute minimal imports from" <+> ppr n
1248 n_mod = moduleName (nameModule n)
1252 %************************************************************************
1256 %************************************************************************
1259 badImportItemErr iface decl_spec ie
1260 = sep [ptext SLIT("Module"), quotes (ppr (is_mod decl_spec)), source_import,
1261 ptext SLIT("does not export"), quotes (ppr ie)]
1263 source_import | mi_boot iface = ptext SLIT("(hi-boot interface)")
1266 illegalImportItemErr = ptext SLIT("Illegal import item")
1268 dodgyImportWarn item = dodgyMsg (ptext SLIT("import")) item
1269 dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) item
1272 = sep [ ptext SLIT("The") <+> kind <+> ptext SLIT("item") <+> quotes (ppr (IEThingAll tc)),
1273 ptext SLIT("suggests that") <+> quotes (ppr tc) <+> ptext SLIT("has constructor or class methods"),
1274 ptext SLIT("but it has none; it is a type synonym or abstract type or class") ]
1276 exportItemErr export_item
1277 = sep [ ptext SLIT("The export item") <+> quotes (ppr export_item),
1278 ptext SLIT("attempts to export constructors or class methods that are not visible here") ]
1280 typeItemErr name wherestr
1281 = sep [ ptext SLIT("Using 'type' tag on") <+> quotes (ppr name) <+> wherestr,
1282 ptext SLIT("Use -findexed-types to enable this extension") ]
1284 exportClashErr global_env name1 name2 ie1 ie2
1285 = vcat [ ptext SLIT("Conflicting exports for") <+> quotes (ppr occ) <> colon
1286 , ppr_export ie1 name1
1287 , ppr_export ie2 name2 ]
1289 occ = nameOccName name1
1290 ppr_export ie name = nest 2 (quotes (ppr ie) <+> ptext SLIT("exports") <+>
1291 quotes (ppr name) <+> pprNameProvenance (get_gre name))
1293 -- get_gre finds a GRE for the Name, so that we can show its provenance
1295 = case lookupGRE_Name global_env name of
1297 [] -> pprPanic "exportClashErr" (ppr name)
1299 addDupDeclErr :: Name -> Name -> TcRn ()
1300 addDupDeclErr name_a name_b
1301 = addErrAt (srcLocSpan loc2) $
1302 vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr name1),
1303 ptext SLIT("Declared at:") <+> vcat [ppr (nameSrcLoc name1), ppr loc2]]
1305 loc2 = nameSrcLoc name2
1306 (name1,name2) | nameSrcLoc name_a > nameSrcLoc name_b = (name_b,name_a)
1307 | otherwise = (name_a,name_b)
1308 -- Report the error at the later location
1310 dupExportWarn occ_name ie1 ie2
1311 = hsep [quotes (ppr occ_name),
1312 ptext SLIT("is exported by"), quotes (ppr ie1),
1313 ptext SLIT("and"), quotes (ppr ie2)]
1316 = hsep [ptext SLIT("Duplicate"),
1317 quotes (ptext SLIT("Module") <+> ppr mod),
1318 ptext SLIT("in export list")]
1320 nullModuleExport mod
1321 = ptext SLIT("The export item `module") <+> ppr mod <> ptext SLIT("' exports nothing")
1323 moduleDeprec mod txt
1324 = sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"),