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, isTcOcc, pprNonVarNameSpace,
35 OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv,
37 import HscTypes ( GenAvailInfo(..), AvailInfo, availNames, availName,
38 HomePackageTable, PackageIfaceTable,
39 mkPrintUnqualified, availsToNameSet,
41 Deprecs(..), ModIface(..), Dependencies(..),
42 lookupIfaceByModule, ExternalPackageState(..)
44 import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace,
45 GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
46 emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts,
47 extendGlobalRdrEnv, lookupGlobalRdrEnv, unQualOK, lookupGRE_Name,
48 Provenance(..), ImportSpec(..), ImpDeclSpec(..), ImpItemSpec(..),
49 importSpecLoc, importSpecModule, isLocalGRE, pprNameProvenance )
53 import SrcLoc ( Located(..), mkGeneralSrcSpan, getLoc,
54 unLoc, noLoc, srcLocSpan, SrcSpan )
57 import BasicTypes ( DeprecTxt )
58 import DriverPhases ( isHsBoot )
59 import Util ( notNull )
60 import Data.List ( nub, partition, concatMap )
61 import IO ( openFile, IOMode(..) )
67 %************************************************************************
71 %************************************************************************
74 rnImports :: [LImportDecl RdrName]
75 -> RnM ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
78 -- PROCESS IMPORT DECLS
79 -- Do the non {- SOURCE -} ones first, so that we get a helpful
80 -- warning for {- SOURCE -} ones that are unnecessary
81 = do this_mod <- getModule
82 implicit_prelude <- doptM Opt_ImplicitPrelude
83 let all_imports = mk_prel_imports this_mod implicit_prelude ++ imports
84 (source, ordinary) = partition is_source_import all_imports
85 is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
87 stuff1 <- mapM (rnImportDecl this_mod) ordinary
88 stuff2 <- mapM (rnImportDecl this_mod) source
89 let (decls, rdr_env, avails, imp_avails) = combine (stuff1 ++ stuff2)
90 return (decls, rdr_env,
91 imp_avails{ imp_parent = availsToNameEnv (nubAvails avails) })
92 -- why wait until now to set the imp_parent, rather than
93 -- setting it in rnImportDecl for each import, and
94 -- combining them with plusImportAvails? The reason is
95 -- that we need to combine all the AvailInfos *before*
96 -- we build the NameEnv, otherwise the NameEnv can
97 -- end up with inconsistencies, eg. the parent can say
98 -- C(m1,m2), but the entry for m2 might only say C(m2).
99 -- The test mod118 illustrates the bug.
101 -- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();
102 -- because the former doesn't even look at Prelude.hi for instance
103 -- declarations, whereas the latter does.
104 mk_prel_imports this_mod implicit_prelude
105 | this_mod == pRELUDE
106 || explicit_prelude_import
107 || not implicit_prelude
109 | otherwise = [preludeImportDecl]
110 explicit_prelude_import
111 = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports,
112 unLoc mod == pRELUDE_NAME ]
114 combine :: [(LImportDecl Name, GlobalRdrEnv, [AvailInfo], ImportAvails)]
115 -> ([LImportDecl Name], GlobalRdrEnv, [AvailInfo], ImportAvails)
116 combine = foldr plus ([], emptyGlobalRdrEnv, [], emptyImportAvails)
117 where plus (decl, gbl_env1, avails1, imp_avails1)
118 (decls, gbl_env2, avails2, imp_avails2)
120 gbl_env1 `plusGlobalRdrEnv` gbl_env2,
122 imp_avails1 `plusImportAvails` imp_avails2)
124 preludeImportDecl :: LImportDecl RdrName
127 ImportDecl (L loc pRELUDE_NAME)
128 False {- Not a boot interface -}
129 False {- Not qualified -}
130 Nothing {- No "as" -}
131 Nothing {- No import list -}
133 loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
137 rnImportDecl :: Module
138 -> LImportDecl RdrName
139 -> RnM (LImportDecl Name, GlobalRdrEnv,
140 [AvailInfo], ImportAvails)
142 rnImportDecl this_mod (L loc (ImportDecl loc_imp_mod_name want_boot
143 qual_only as_mod imp_details))
147 -- If there's an error in loadInterface, (e.g. interface
148 -- file not found) we get lots of spurious errors from 'filterImports'
150 imp_mod_name = unLoc loc_imp_mod_name
151 doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
153 iface <- loadSrcInterface doc imp_mod_name want_boot
155 -- Compiler sanity check: if the import didn't say
156 -- {-# SOURCE #-} we should not get a hi-boot file
157 WARN( not want_boot && mi_boot iface, ppr imp_mod_name ) $ do
159 -- Issue a user warning for a redundant {- SOURCE -} import
160 -- NB that we arrange to read all the ordinary imports before
161 -- any of the {- SOURCE -} imports
162 warnIf (want_boot && not (mi_boot iface))
163 (warnRedundantSourceImport imp_mod_name)
166 imp_mod = mi_module iface
167 deprecs = mi_deprecs iface
168 is_orph = mi_orphan iface
171 filtered_exports = filter not_this_mod (mi_exports iface)
172 not_this_mod (mod,_) = mod /= this_mod
173 -- If the module exports anything defined in this module, just
174 -- ignore it. Reason: otherwise it looks as if there are two
175 -- local definition sites for the thing, and an error gets
176 -- reported. Easiest thing is just to filter them out up
177 -- front. This situation only arises if a module imports
178 -- itself, or another module that imported it. (Necessarily,
179 -- this invoves a loop.)
181 -- Tiresome consequence: if you say
186 -- module B( AType ) where
187 -- import {-# SOURCE #-} A( AType )
189 -- then you'll get a 'B does not export AType' message. Oh well.
191 qual_mod_name = case as_mod of
192 Nothing -> imp_mod_name
193 Just another_name -> another_name
194 imp_spec = ImpDeclSpec { is_mod = imp_mod_name, is_qual = qual_only,
195 is_dloc = loc, is_as = qual_mod_name }
198 -- Get the total exports from this module
199 total_avails <- ifaceExportNames filtered_exports
201 -- filter the imports according to the import declaration
202 (new_imp_details, filtered_avails, gbl_env) <-
203 filterImports iface imp_spec imp_details total_avails
208 -- Compute new transitive dependencies
210 orphans | is_orph = ASSERT( not (imp_mod `elem` dep_orphs deps) )
211 imp_mod : dep_orphs deps
212 | otherwise = dep_orphs deps
214 pkg = modulePackageId (mi_module iface)
216 (dependent_mods, dependent_pkgs)
217 | pkg == thisPackage dflags =
218 -- Imported module is from the home package
219 -- Take its dependent modules and add imp_mod itself
220 -- Take its dependent packages unchanged
222 -- NB: (dep_mods deps) might include a hi-boot file
223 -- for the module being compiled, CM. Do *not* filter
224 -- this out (as we used to), because when we've
225 -- finished dealing with the direct imports we want to
226 -- know if any of them depended on CM.hi-boot, in
227 -- which case we should do the hi-boot consistency
228 -- check. See LoadIface.loadHiBootInterface
229 ((imp_mod_name, want_boot) : dep_mods deps, dep_pkgs deps)
232 -- Imported module is from another package
233 -- Dump the dependent modules
234 -- Add the package imp_mod comes from to the dependent packages
235 ASSERT2( not (pkg `elem` dep_pkgs deps), ppr pkg <+> ppr (dep_pkgs deps) )
236 ([], pkg : dep_pkgs deps)
238 -- True <=> import M ()
239 import_all = case imp_details of
240 Just (is_hiding, ls) -> not is_hiding && null ls
243 imports = ImportAvails {
244 imp_env = unitUFM qual_mod_name filtered_avails,
245 imp_mods = unitModuleEnv imp_mod (imp_mod, import_all, loc),
247 imp_dep_mods = mkModDeps dependent_mods,
248 imp_dep_pkgs = dependent_pkgs,
249 imp_parent = emptyNameEnv
254 -- Complain if we import a deprecated module
255 ifOptM Opt_WarnDeprecations (
257 DeprecAll txt -> addWarn (moduleDeprec imp_mod_name txt)
261 let new_imp_decl = L loc (ImportDecl loc_imp_mod_name want_boot
262 qual_only as_mod new_imp_details)
264 returnM (new_imp_decl, gbl_env, filtered_avails, imports)
266 warnRedundantSourceImport mod_name
267 = ptext SLIT("Unnecessary {-# SOURCE #-} in the import of module")
268 <+> quotes (ppr mod_name)
272 %************************************************************************
274 importsFromLocalDecls
276 %************************************************************************
278 From the top-level declarations of this module produce
279 * the lexical environment
281 created by its bindings.
283 Complain about duplicate bindings
286 importsFromLocalDecls :: HsGroup RdrName -> RnM TcGblEnv
287 importsFromLocalDecls group
288 = do { gbl_env <- getGblEnv
290 ; avails <- getLocalDeclBinders gbl_env group
292 ; implicit_prelude <- doptM Opt_ImplicitPrelude
294 -- Optimisation: filter out names for built-in syntax
295 -- They just clutter up the environment (esp tuples), and the parser
296 -- will generate Exact RdrNames for them, so the cluttered
297 -- envt is no use. To avoid doing this filter all the time,
298 -- we use -fno-implicit-prelude as a clue that the filter is
299 -- worth while. Really, it's only useful for GHC.Base and GHC.Tuple.
301 -- It's worth doing because it makes the environment smaller for
302 -- every module that imports the Prelude
304 -- Note: don't filter the gbl_env (hence all_names, not filered_all_names
305 -- in defn of gres above). Stupid reason: when parsing
306 -- data type decls, the constructors start as Exact tycon-names,
307 -- and then get turned into data con names by zapping the name space;
308 -- but that stops them being Exact, so they get looked up.
309 -- Ditto in fixity decls; e.g. infix 5 :
310 -- Sigh. It doesn't matter because it only affects the Data.Tuple really.
311 -- The important thing is to trim down the exports.
312 names = concatMap availNames avails;
315 | implicit_prelude = avails
316 | otherwise = filterAvails (not.isBuiltInSyntax) avails;
318 ; this_mod = tcg_mod gbl_env
319 ; imports = emptyImportAvails {
320 imp_env = unitUFM (moduleName this_mod)
322 imp_parent = availsToNameEnv avails
326 ; rdr_env' <- extendRdrEnvRn (tcg_rdr_env gbl_env) names
328 ; traceRn (text "local avails: " <> ppr avails)
330 ; returnM (gbl_env { tcg_rdr_env = rdr_env',
331 tcg_imports = imports `plusImportAvails` tcg_imports gbl_env })
334 extendRdrEnvRn :: GlobalRdrEnv -> [Name] -> RnM GlobalRdrEnv
335 -- Add the new locally-bound names one by one, checking for duplicates as
336 -- we do so. Remember that in Template Haskell the duplicates
337 -- might *already be* in the GlobalRdrEnv from higher up the module
338 extendRdrEnvRn rdr_env names
339 = foldlM add_local rdr_env names
341 add_local rdr_env name
342 | gres <- lookupGlobalRdrEnv rdr_env (nameOccName name)
343 , (dup_gre:_) <- filter isLocalGRE gres -- Check for existing *local* defns
344 = do { addDupDeclErr (gre_name dup_gre) name
347 = return (extendGlobalRdrEnv rdr_env new_gre)
349 new_gre = GRE {gre_name = name, gre_prov = LocalDef}
352 @getLocalDeclBinders@ returns the names for an @HsDecl@. It's
353 used for source code.
355 *** See "THE NAMING STORY" in HsDecls ****
357 Instances of indexed types
358 ~~~~~~~~~~~~~~~~~~~~~~~~~~
359 Indexed data/newtype instances contain data constructors that we need to
360 collect, too. Moreover, we need to descend into the data/newtypes instances
361 of associated families.
363 We need to be careful with the handling of the type constructor of each type
364 instance as the family constructor is already defined, and we want to avoid
365 raising a duplicate declaration error. So, we make a new name for it, but
366 don't return it in the 'AvailInfo'.
369 getLocalDeclBinders :: TcGblEnv -> HsGroup RdrName -> RnM [AvailInfo]
370 getLocalDeclBinders gbl_env (HsGroup {hs_valds = ValBindsIn val_decls val_sigs,
371 hs_tyclds = tycl_decls,
372 hs_instds = inst_decls,
373 hs_fords = foreign_decls })
374 = do { tc_names_s <- mappM new_tc tycl_decls
375 ; at_names_s <- mappM inst_ats inst_decls
376 ; val_names <- mappM new_simple val_bndrs
377 ; return (val_names ++ tc_names_s ++ concat at_names_s) }
379 mod = tcg_mod gbl_env
380 is_hs_boot = isHsBoot (tcg_src gbl_env) ;
381 val_bndrs | is_hs_boot = sig_hs_bndrs
382 | otherwise = for_hs_bndrs ++ val_hs_bndrs
383 -- In a hs-boot file, the value binders come from the
384 -- *signatures*, and there should be no foreign binders
386 new_simple rdr_name = do
387 nm <- newTopSrcBinder mod rdr_name
390 sig_hs_bndrs = [nm | L _ (TypeSig nm _) <- val_sigs]
391 val_hs_bndrs = collectHsBindLocatedBinders val_decls
392 for_hs_bndrs = [nm | L _ (ForeignImport nm _ _) <- foreign_decls]
395 | isIdxTyDecl (unLoc tc_decl)
396 = do { main_name <- lookupFamInstDeclBndr mod main_rdr
397 ; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
398 ; return (AvailTC main_name sub_names) }
399 -- main_name is not bound here!
401 = do { main_name <- newTopSrcBinder mod main_rdr
402 ; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
403 ; return (AvailTC main_name (main_name : sub_names)) }
405 (main_rdr : sub_rdrs) = tyClDeclNames (unLoc tc_decl)
408 = mappM new_tc (instDeclATs (unLoc inst_decl))
412 %************************************************************************
414 \subsection{Filtering imports}
416 %************************************************************************
418 @filterImports@ takes the @ExportEnv@ telling what the imported module makes
419 available, and filters it through the import spec (if any).
422 filterImports :: ModIface
423 -> ImpDeclSpec -- The span for the entire import decl
424 -> Maybe (Bool, [LIE RdrName]) -- Import spec; True => hiding
425 -> [AvailInfo] -- What's available
426 -> RnM (Maybe (Bool, [LIE Name]), -- Import spec w/ Names
427 [AvailInfo], -- What's imported
428 GlobalRdrEnv) -- Same again, but in GRE form
430 filterImports iface decl_spec Nothing all_avails
431 = return (Nothing, all_avails, mkGenericRdrEnv decl_spec all_avails)
433 filterImports iface decl_spec (Just (want_hiding, import_items)) all_avails
435 -- check for errors, convert RdrNames to Names
436 opt_indexedtypes <- doptM Opt_IndexedTypes
437 items1 <- mapM (lookup_lie opt_indexedtypes) import_items
439 let -- build the AvailInfo corresponding to each import item.
440 items2 = [ (ie, filterAvailByIE (unLoc ie) av)
441 | (ie,av) <- concat items1 ]
443 -- eliminate duplicates
444 avails = nubAvails (map snd items2)
446 -- the new import spec, with Names instead of RdrNames
447 imp_spec_out = Just (want_hiding, map fst items2)
452 keep n = not (n `elemNameSet` availsToNameSet avails)
453 pruned_avails = filterAvails keep all_avails
455 traceRn (text "pruned_avails: " <> ppr pruned_avails)
456 return (imp_spec_out, pruned_avails,
457 mkGenericRdrEnv decl_spec pruned_avails)
461 gres = concat [ mkGlobalRdrEltsFromIE decl_spec lie avail
462 | (lie, avail) <- items2 ]
464 traceRn (text "imported avails: " <> ppr avails)
465 return (imp_spec_out, avails, mkGlobalRdrEnv gres)
467 -- This environment is how we map names mentioned in the import
468 -- list to the actual Name they correspond to, and the family
469 -- that the Name belongs to (an AvailInfo).
471 -- This env will have entries for data constructors too,
472 -- they won't make any difference because naked entities like T
473 -- in an import list map to TcOccs, not VarOccs.
474 occ_env :: OccEnv (Name,AvailInfo)
475 occ_env = mkOccEnv [ (nameOccName n, (n,a))
476 | a <- all_avails, n <- availNames a ]
478 lookup_lie :: Bool -> LIE RdrName -> TcRn [(LIE Name, AvailInfo)]
479 lookup_lie opt_indexedtypes (L loc ieRdr)
481 stuff <- setSrcSpan loc $
482 case lookup_ie opt_indexedtypes ieRdr of
483 Failed err -> addErr err >> return []
484 Succeeded a -> return a
485 checkDodgyImport stuff
486 return [ (L loc ie, avail) | (ie,avail) <- stuff ]
488 -- warn when importing T(..) if T was exported absgtractly
489 checkDodgyImport stuff
490 | IEThingAll n <- ieRdr, (_, AvailTC _ [one]):_ <- stuff
491 = ifOptM Opt_WarnDodgyImports (addWarn (dodgyImportWarn n))
492 -- NB. use the RdrName for reporting the warning
496 -- For each import item, we convert its RdrNames to Names,
497 -- and at the same time construct an AvailInfo corresponding
498 -- to what is actually imported by this item.
499 -- Returns Nothing on error.
500 -- We return a list here, because in the case of an import
501 -- item like C, if we are hiding, then C refers to *both* a
502 -- type/class and a data constructor.
503 lookup_ie :: Bool -> IE RdrName -> MaybeErr Message [(IE Name,AvailInfo)]
504 lookup_ie opt_indexedtypes ie
505 = let bad_ie = Failed (badImportItemErr iface decl_spec ie)
507 lookup_name rdrName =
508 case lookupOccEnv occ_env (rdrNameOcc rdrName) of
514 (name,avail) <- lookup_name n
515 return [(IEVar name, avail)]
518 (name,avail) <- lookup_name tc
519 return [(IEThingAll name, avail)]
522 | want_hiding -- hiding ( C )
523 -- Here the 'C' can be a data constructor
524 -- *or* a type/class, or even both
525 -> let tc_name = lookup_name tc
526 dc_name = lookup_name (setRdrNameSpace tc srcDataName)
528 case catMaybeErr [ tc_name, dc_name ] of
530 names -> return [ (IEThingAbs n, av) | (n,av) <- names ]
532 -> do (name,avail) <- lookup_name tc
533 return [(IEThingAbs name, avail)]
535 IEThingWith n ns -> do
536 (name,avail) <- lookup_name n
538 AvailTC nm subnames | nm == name -> do
539 let env = mkOccEnv [ (nameOccName s, s)
541 let mb_children = map (lookupOccEnv env . rdrNameOcc) ns
543 if any isNothing mb_children
545 else return (catMaybes mb_children)
546 -- check for proper import of indexed types
547 when (not opt_indexedtypes && any isTyConName children) $
548 Failed (typeItemErr (head . filter isTyConName
550 (text "in import list"))
551 return [(IEThingWith name children, avail)]
554 _other -> Failed illegalImportItemErr
555 -- could be IEModuleContents, IEGroup, IEDoc, IEDocNamed
558 catMaybeErr :: [MaybeErr err a] -> [a]
559 catMaybeErr ms = [ a | Succeeded a <- ms ]
562 %************************************************************************
566 %************************************************************************
569 -- | make a 'GlobalRdrEnv' where all the elements point to the same
570 -- import declaration (useful for "hiding" imports, or imports with
572 mkGenericRdrEnv decl_spec avails
573 = mkGlobalRdrEnv [ GRE { gre_name = name, gre_prov = Imported [imp_spec] }
574 | name <- concatMap availNames avails ]
576 imp_spec = ImpSpec { is_decl = decl_spec, is_item = ImpAll }
579 -- | filters an 'AvailInfo' by the given import/export spec.
580 filterAvailByIE :: IE Name -> AvailInfo -> AvailInfo
581 filterAvailByIE (IEVar n) a@(Avail _) = a
582 filterAvailByIE (IEVar n) a@(AvailTC tc subs) = AvailTC tc [n]
583 filterAvailByIE (IEThingAbs n) a@(AvailTC _ _) = AvailTC n [n]
584 filterAvailByIE (IEThingAll n) a@(AvailTC tc subs) = a
585 filterAvailByIE (IEThingWith n ns) a@(AvailTC tc subs) =
586 AvailTC tc (filter (`elem` (n:ns)) subs)
587 filterAvailByIE _ _ = panic "filterAvailByIE"
589 -- | filters 'AvailInfo's by the given predicate
590 filterAvails :: (Name -> Bool) -> [AvailInfo] -> [AvailInfo]
591 filterAvails keep avails = foldr (filterAvail keep) [] avails
593 -- | filters an 'AvailInfo' by the given predicate
594 filterAvail :: (Name -> Bool) -> AvailInfo -> [AvailInfo] -> [AvailInfo]
595 filterAvail keep ie rest =
597 Avail n | keep n -> ie : rest
600 let left = filter keep ns in
601 if null left then rest else AvailTC tc left : rest
603 -- | combines 'AvailInfo's from the same family
604 nubAvails :: [AvailInfo] -> [AvailInfo]
605 nubAvails avails = nameEnvElts (foldr add emptyNameEnv avails)
607 add avail env = extendNameEnv_C comb_avails env (availName avail) avail
608 comb_avails (AvailTC tc subs1) (AvailTC _ subs2)
609 = AvailTC tc (nub (subs1 ++ subs2))
610 comb_avails avail _ = avail
612 -- | Given an import/export spec, construct the appropriate 'GlobalRdrElt's.
613 mkGlobalRdrEltsFromIE :: ImpDeclSpec -> LIE Name -> AvailInfo -> [GlobalRdrElt]
614 mkGlobalRdrEltsFromIE decl_spec (L loc ie) avail =
617 [mk_explicit_gre name]
619 [mk_explicit_gre name]
620 IEThingAll name | AvailTC _ subs <- avail ->
621 mk_explicit_gre name : map mk_implicit_gre subs
622 IEThingWith name subs ->
623 mk_explicit_gre name : map mk_explicit_gre subs
625 panic "mkGlobalRdrEltsFromIE"
627 mk_explicit_gre = mk_gre True
628 mk_implicit_gre = mk_gre False
630 mk_gre explicit name = GRE { gre_name = name,
631 gre_prov = Imported [imp_spec] }
633 imp_spec = ImpSpec { is_decl = decl_spec, is_item = item_spec }
634 item_spec = ImpSome { is_explicit = explicit, is_iloc = loc }
638 %************************************************************************
640 \subsection{Export list processing}
642 %************************************************************************
644 Processing the export list.
646 You might think that we should record things that appear in the export
647 list as ``occurrences'' (using @addOccurrenceName@), but you'd be
648 wrong. We do check (here) that they are in scope, but there is no
649 need to slurp in their actual declaration (which is what
650 @addOccurrenceName@ forces).
652 Indeed, doing so would big trouble when compiling @PrelBase@, because
653 it re-exports @GHC@, which includes @takeMVar#@, whose type includes
654 @ConcBase.StateAndSynchVar#@, and so on...
657 type ExportAccum -- The type of the accumulating parameter of
658 -- the main worker function in rnExports
659 = ([LIE Name], -- export items with Names
660 ExportOccMap, -- Tracks exported occurrence names
661 [AvailInfo]) -- The accumulated exported stuff
662 emptyExportAccum = ([], emptyOccEnv, [])
664 type ExportOccMap = OccEnv (Name, IE RdrName)
665 -- Tracks what a particular exported OccName
666 -- in an export list refers to, and which item
667 -- it came from. It's illegal to export two distinct things
668 -- that have the same occurrence name
670 rnExports :: Bool -- False => no 'module M(..) where' header at all
671 -> Maybe [LIE RdrName] -- Nothing => no explicit export list
672 -> RnM (Maybe [LIE Name], [AvailInfo])
674 -- Complains if two distinct exports have same OccName
675 -- Warns about identical exports.
676 -- Complains about exports items not in scope
678 rnExports explicit_mod exports
679 = do TcGblEnv { tcg_mod = this_mod,
680 tcg_rdr_env = rdr_env,
681 tcg_imports = imports } <- getGblEnv
683 -- If the module header is omitted altogether, then behave
684 -- as if the user had written "module Main(main) where..."
685 -- EXCEPT in interactive mode, when we behave as if he had
686 -- written "module Main where ..."
687 -- Reason: don't want to complain about 'main' not in scope
688 -- in interactive mode
689 ghc_mode <- getGhcMode
694 | ghc_mode == Interactive
697 -> do mainName <- lookupGlobalOccRn main_RDR_Unqual
698 return (Just ([noLoc (IEVar main_RDR_Unqual)]))
699 -- ToDo: the 'noLoc' here is unhelpful if 'main' turns
700 -- out to be out of scope
702 (exp_spec, avails) <- exports_from_avail real_exports rdr_env
704 return (exp_spec, nubAvails avails)
707 exports_from_avail :: Maybe [LIE RdrName]
708 -- Nothing => no explicit export list
712 -> RnM (Maybe [LIE Name], [AvailInfo])
714 exports_from_avail Nothing rdr_env imports this_mod
715 = -- the same as (module M) where M is the current module name,
716 -- so that's how we handle it.
718 names = [ gre_name gre | gre <- globalRdrEnvElts rdr_env,
720 avails = map (lookupNameEnv_NF (imp_parent imports)) names
722 return (Nothing, avails)
724 exports_from_avail (Just rdr_items) rdr_env imports this_mod
725 = do traceRn (text "parent: " <> ppr (imp_parent imports))
726 (ie_names, _, exports) <- foldlM do_litem emptyExportAccum rdr_items
727 return (Just ie_names, exports)
729 do_litem :: ExportAccum -> LIE RdrName -> RnM ExportAccum
730 do_litem acc lie = setSrcSpan (getLoc lie) (exports_from_item acc lie)
732 exports_from_item :: ExportAccum -> LIE RdrName -> RnM ExportAccum
733 exports_from_item acc@(ie_names, occs, exports)
734 (L loc ie@(IEModuleContents mod))
735 | mod `elem` mods -- Duplicate export of M
736 = do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
737 warnIf warn_dup_exports (dupModuleExport mod) ;
741 = case lookupUFM (imp_env imports) mod of
742 Nothing -> do addErr (modExportErr mod)
745 -> do traceRn (text "mod avails: " <> ppr mod <+> ppr avails)
746 let avails' = filterAvails (inScopeUnqual rdr_env) $
748 new_exps = concatMap availNames avails'
750 occs' <- check_occs ie occs new_exps
751 -- This check_occs not only finds conflicts
752 -- between this item and others, but also
753 -- internally within this item. That is, if
754 -- 'M.x' is in scope in several ways, we'll have
755 -- several members of mod_avails with the same
757 return (L loc (IEModuleContents mod) : ie_names,
758 occs', avails' ++ exports)
760 mods = [ mod | (L _ (IEModuleContents mod)) <- ie_names ]
762 exports_from_item acc@(lie_names, occs, exports) (L loc ie)
763 = do new_ie <- lookup_ie ie
764 let ie_name = ieName new_ie
765 if isUnboundName ie_name
766 then return acc -- Avoid error cascade
768 if isDoc new_ie -- deal with docs
769 then return (L loc new_ie : lie_names, occs, exports)
771 traceRn (text "lookup_avail: " <> ppr (lookup_avail ie_name))
772 let avail = filterAvailByIE new_ie (lookup_avail ie_name)
773 new_exports = case new_ie of
774 IEThingWith n ns -> n : ns
775 _ -> availNames avail
776 -- ^^^ an IEThingWith might contain duplicates
777 -- whereas the avail doesn't, but we want
778 -- duplicates to be noticed by check_occs below.
779 -- checkErr (not (null (drop 1 new_exports))) (exportItemErr ie)
780 checkForDodgyExport new_ie new_exports
781 occs' <- check_occs ie occs new_exports
782 return (L loc new_ie : lie_names, occs', avail : exports)
784 lookup_avail :: Name -> AvailInfo
786 case lookupNameEnv avail_env name of
787 Nothing -> pprPanic "rnExports:lookup_avail" (ppr name)
789 where avail_env = imp_parent imports
791 lookup_ie :: IE RdrName -> RnM (IE Name)
793 lookup_ie (IEVar rdr)
794 = do name <- lookupGlobalOccRn rdr
797 lookup_ie (IEThingAbs rdr)
798 = do name <- lookupGlobalOccRn rdr
799 return (IEThingAbs name)
801 lookup_ie (IEThingAll rdr)
802 = do name <- lookupGlobalOccRn rdr
803 return (IEThingAll name)
805 lookup_ie ie@(IEThingWith rdr sub_rdrs)
806 = do name <- lookupGlobalOccRn rdr
807 if isUnboundName name
808 then return (IEThingWith name [])
810 let avail = lookup_avail name
811 env = mkOccEnv [ (nameOccName s, s)
812 | AvailTC _ subnames <- [avail],
814 let mb_names = map (lookupOccEnv env . rdrNameOcc) sub_rdrs
815 if any isNothing mb_names
816 then do addErr (exportItemErr ie)
817 return (IEThingWith name [])
818 else do let names = catMaybes mb_names
819 optIdxTypes <- doptM Opt_IndexedTypes
820 when (not optIdxTypes && any isTyConName names) $
821 addErr (typeItemErr ( head
824 (text "in export list"))
825 return (IEThingWith name (catMaybes mb_names))
827 lookup_ie (IEGroup lev doc)
828 = do rn_doc <- rnHsDoc doc
829 return (IEGroup lev rn_doc)
830 lookup_ie (IEDoc doc)
831 = do rn_doc <- rnHsDoc doc
832 return (IEDoc rn_doc)
833 lookup_ie (IEDocNamed str)
834 = return (IEDocNamed str)
836 lookup_ie (IEModuleContents _)
837 = panic "rnExports:lookup_ie" -- caught earlier
840 isDoc (IEDoc _) = True
841 isDoc (IEDocNamed _) = True
842 isDoc (IEGroup _ _) = True
845 -------------------------------
846 inScopeUnqual :: GlobalRdrEnv -> Name -> Bool
847 -- Checks whether the Name is in scope unqualified,
848 -- regardless of whether it's ambiguous or not
849 inScopeUnqual env n = any unQualOK (lookupGRE_Name env n)
851 -------------------------------
852 checkForDodgyExport :: IE Name -> [Name] -> RnM ()
853 checkForDodgyExport ie@(IEThingAll tc) [n]
854 | isTcOcc (nameOccName n) = addWarn (dodgyExportWarn tc)
855 -- This occurs when you export T(..), but
856 -- only import T abstractly, or T is a synonym.
857 -- The single [n] is the type or class itself
858 | otherwise = addErr (exportItemErr ie)
859 -- This happes if you export x(..), which is bogus
860 checkForDodgyExport _ _ = return ()
862 -------------------------------
863 check_occs :: IE RdrName -> ExportOccMap -> [Name] -> RnM ExportOccMap
864 check_occs ie occs names
865 = foldlM check occs names
868 = case lookupOccEnv occs name_occ of
869 Nothing -> returnM (extendOccEnv occs name_occ (name, ie))
872 | name == name' -- Duplicate export
873 -> do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
874 warnIf warn_dup_exports (dupExportWarn name_occ ie ie') ;
877 | otherwise -- Same occ name but different names: an error
878 -> do { global_env <- getGlobalRdrEnv ;
879 addErr (exportClashErr global_env name' name ie' ie) ;
882 name_occ = nameOccName name
885 %*********************************************************
889 %*********************************************************
892 reportDeprecations :: DynFlags -> TcGblEnv -> RnM ()
893 reportDeprecations dflags tcg_env
894 = ifOptM Opt_WarnDeprecations $
895 do { (eps,hpt) <- getEpsAndHpt
896 -- By this time, typechecking is complete,
897 -- so the PIT is fully populated
898 ; mapM_ (check hpt (eps_PIT eps)) all_gres }
900 used_names = allUses (tcg_dus tcg_env)
901 -- Report on all deprecated uses; hence allUses
902 all_gres = globalRdrEnvElts (tcg_rdr_env tcg_env)
904 avail_env = imp_parent (tcg_imports tcg_env)
906 check hpt pit (GRE {gre_name = name, gre_prov = Imported (imp_spec:_)})
907 | name `elemNameSet` used_names
908 , Just deprec_txt <- lookupDeprec dflags hpt pit avail_env name
909 = addWarnAt (importSpecLoc imp_spec)
910 (sep [ptext SLIT("Deprecated use of") <+>
911 pprNonVarNameSpace (occNameSpace (nameOccName name)) <+>
913 (parens imp_msg) <> colon,
916 name_mod = nameModule name
917 imp_mod = importSpecModule imp_spec
918 imp_msg = ptext SLIT("imported from") <+> ppr imp_mod <> extra
919 extra | imp_mod == moduleName name_mod = empty
920 | otherwise = ptext SLIT(", but defined in") <+> ppr name_mod
922 check hpt pit ok_gre = returnM () -- Local, or not used, or not deprectated
923 -- The Imported pattern-match: don't deprecate locally defined names
924 -- For a start, we may be exporting a deprecated thing
925 -- Also we may use a deprecated thing in the defn of another
926 -- deprecated things. We may even use a deprecated thing in
927 -- the defn of a non-deprecated thing, when changing a module's
930 lookupDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
931 -> NameEnv AvailInfo -- parent info
932 -> Name -> Maybe DeprecTxt
933 lookupDeprec dflags hpt pit avail_env n
934 = case lookupIfaceByModule dflags hpt pit (nameModule n) of
935 Just iface -> mi_dep_fn iface n `seqMaybe` -- Bleat if the thing, *or
936 mi_dep_fn iface (nameParent n) -- its parent*, is deprec'd
938 | isWiredInName n -> Nothing
939 -- We have not necessarily loaded the .hi file for a
940 -- wired-in name (yet), although we *could*.
941 -- And we never deprecate them
943 | otherwise -> pprPanic "lookupDeprec" (ppr n)
944 -- By now all the interfaces should have been loaded
946 nameParent n = case lookupNameEnv avail_env n of
947 Just (AvailTC parent _) -> parent
950 gre_is_used :: NameSet -> GlobalRdrElt -> Bool
951 gre_is_used used_names gre = gre_name gre `elemNameSet` used_names
954 %*********************************************************
958 %*********************************************************
961 reportUnusedNames :: Maybe [LIE RdrName] -- Export list
962 -> TcGblEnv -> RnM ()
963 reportUnusedNames export_decls gbl_env
964 = do { traceRn ((text "RUN") <+> (ppr (tcg_dus gbl_env)))
965 ; warnUnusedTopBinds unused_locals
966 ; warnUnusedModules unused_imp_mods
967 ; warnUnusedImports unused_imports
968 ; warnDuplicateImports defined_and_used
969 ; printMinimalImports minimal_imports }
971 used_names, all_used_names :: NameSet
972 used_names = findUses (tcg_dus gbl_env) emptyNameSet
973 -- NB: currently, if f x = g, we only treat 'g' as used if 'f' is used
976 avail_env = imp_parent (tcg_imports gbl_env)
977 nameParent_maybe n = case lookupNameEnv avail_env n of
978 Just (AvailTC tc _) | tc /= n -> Just tc
979 _otherwise -> Nothing
981 all_used_names = used_names `unionNameSets`
982 mkNameSet (mapCatMaybes nameParent_maybe (nameSetToList used_names))
983 -- A use of C implies a use of T,
984 -- if C was brought into scope by T(..) or T(C)
986 -- Collect the defined names from the in-scope environment
987 defined_names :: [GlobalRdrElt]
988 defined_names = globalRdrEnvElts (tcg_rdr_env gbl_env)
990 -- Note that defined_and_used, defined_but_not_used
991 -- are both [GRE]; that's why we need defined_and_used
992 -- rather than just all_used_names
993 defined_and_used, defined_but_not_used :: [GlobalRdrElt]
994 (defined_and_used, defined_but_not_used)
995 = partition (gre_is_used all_used_names) defined_names
997 -- Filter out the ones that are
998 -- (a) defined in this module, and
999 -- (b) not defined by a 'deriving' clause
1000 -- The latter have an Internal Name, so we can filter them out easily
1001 unused_locals :: [GlobalRdrElt]
1002 unused_locals = filter is_unused_local defined_but_not_used
1003 is_unused_local :: GlobalRdrElt -> Bool
1004 is_unused_local gre = isLocalGRE gre && isExternalName (gre_name gre)
1006 unused_imports :: [GlobalRdrElt]
1007 unused_imports = filter unused_imp defined_but_not_used
1008 unused_imp (GRE {gre_prov = Imported imp_specs})
1009 = not (all (module_unused . importSpecModule) imp_specs)
1010 && or [exp | ImpSpec { is_item = ImpSome { is_explicit = exp } } <- imp_specs]
1011 -- Don't complain about unused imports if we've already said the
1012 -- entire import is unused
1013 unused_imp other = False
1015 -- To figure out the minimal set of imports, start with the things
1016 -- that are in scope (i.e. in gbl_env). Then just combine them
1017 -- into a bunch of avails, so they are properly grouped
1019 -- BUG WARNING: this does not deal properly with qualified imports!
1020 minimal_imports :: FiniteMap ModuleName AvailEnv
1021 minimal_imports0 = foldr add_expall emptyFM expall_mods
1022 minimal_imports1 = foldr add_name minimal_imports0 defined_and_used
1023 minimal_imports = foldr add_inst_mod minimal_imports1 direct_import_mods
1024 -- The last line makes sure that we retain all direct imports
1025 -- even if we import nothing explicitly.
1026 -- It's not necessarily redundant to import such modules. Consider
1030 -- The import M() is not *necessarily* redundant, even if
1031 -- we suck in no instance decls from M (e.g. it contains
1032 -- no instance decls, or This contains no code). It may be
1033 -- that we import M solely to ensure that M's orphan instance
1034 -- decls (or those in its imports) are visible to people who
1035 -- import This. Sigh.
1036 -- There's really no good way to detect this, so the error message
1037 -- in RnEnv.warnUnusedModules is weakened instead
1039 -- We've carefully preserved the provenance so that we can
1040 -- construct minimal imports that import the name by (one of)
1041 -- the same route(s) as the programmer originally did.
1042 add_name (GRE {gre_name = n, gre_prov = Imported imp_specs}) acc
1043 = addToFM_C plusAvailEnv acc (importSpecModule (head imp_specs))
1044 (unitAvailEnv (mk_avail n (nameParent_maybe n)))
1048 -- Modules mentioned as 'module M' in the export list
1049 expall_mods = case export_decls of
1051 Just es -> [m | L _ (IEModuleContents m) <- es]
1053 -- This is really bogus. The idea is that if we see 'module M' in
1054 -- the export list we must retain the import decls that drive it
1055 -- If we aren't careful we might see
1056 -- module A( module M ) where
1059 -- and suppose that N exports everything that M does. Then we
1060 -- must not drop the import of M even though N brings it all into
1063 -- BUG WARNING: 'module M' exports aside, what if M.x is mentioned?!
1065 -- The reason that add_expall is bogus is that it doesn't take
1066 -- qualified imports into account. But it's an improvement.
1067 add_expall mod acc = addToFM_C plusAvailEnv acc mod emptyAvailEnv
1069 -- n is the name of the thing, p is the name of its parent
1070 mk_avail n (Just p) = AvailTC p [p,n]
1071 mk_avail n Nothing | isTcOcc (nameOccName n) = AvailTC n [n]
1072 | otherwise = Avail n
1074 add_inst_mod (mod,_,_) acc
1075 | mod_name `elemFM` acc = acc -- We import something already
1076 | otherwise = addToFM acc mod_name emptyAvailEnv
1078 mod_name = moduleName mod
1079 -- Add an empty collection of imports for a module
1080 -- from which we have sucked only instance decls
1082 imports = tcg_imports gbl_env
1084 direct_import_mods :: [(Module, Bool, SrcSpan)]
1085 -- See the type of the imp_mods for this triple
1086 direct_import_mods = moduleEnvElts (imp_mods imports)
1088 -- unused_imp_mods are the directly-imported modules
1089 -- that are not mentioned in minimal_imports1
1090 -- [Note: not 'minimal_imports', because that includes directly-imported
1091 -- modules even if we use nothing from them; see notes above]
1093 -- BUG WARNING: does not deal correctly with multiple imports of the same module
1094 -- becuase direct_import_mods has only one entry per module
1095 unused_imp_mods = [(mod_name,loc) | (mod,no_imp,loc) <- direct_import_mods,
1096 let mod_name = moduleName mod,
1097 not (mod_name `elemFM` minimal_imports1),
1100 -- The not no_imp part is not to complain about
1101 -- import M (), which is an idiom for importing
1102 -- instance declarations
1104 module_unused :: ModuleName -> Bool
1105 module_unused mod = any (((==) mod) . fst) unused_imp_mods
1107 ---------------------
1108 warnDuplicateImports :: [GlobalRdrElt] -> RnM ()
1109 -- Given the GREs for names that are used, figure out which imports
1110 -- could be omitted without changing the top-level environment.
1112 -- NB: Given import Foo( T )
1113 -- import qualified Foo
1114 -- we do not report a duplicate import, even though Foo.T is brought
1115 -- into scope by both, because there's nothing you can *omit* without
1116 -- changing the top-level environment. So we complain only if it's
1117 -- explicitly named in both imports or neither.
1119 -- Furthermore, we complain about Foo.T only if
1120 -- there is no complaint about (unqualified) T
1122 warnDuplicateImports gres
1123 = ifOptM Opt_WarnUnusedImports $
1124 sequenceM_ [ warn name pr
1125 -- The 'head' picks the first offending group
1126 -- for this particular name
1127 | GRE { gre_name = name, gre_prov = Imported imps } <- gres
1128 , pr <- redundants imps ]
1130 warn name (red_imp, cov_imp)
1131 = addWarnAt (importSpecLoc red_imp)
1132 (vcat [ptext SLIT("Redundant import of:") <+> quotes pp_name,
1133 ptext SLIT("It is also") <+> ppr cov_imp])
1135 pp_name | is_qual red_decl = ppr (is_as red_decl) <> dot <> ppr occ
1136 | otherwise = ppr occ
1137 occ = nameOccName name
1138 red_decl = is_decl red_imp
1140 redundants :: [ImportSpec] -> [(ImportSpec,ImportSpec)]
1141 -- The returned pair is (redundant-import, covering-import)
1143 = [ (red_imp, cov_imp)
1145 , cov_imp <- take 1 (filter (covers red_imp) imps) ]
1147 -- "red_imp" is a putative redundant import
1148 -- "cov_imp" potentially covers it
1149 -- This test decides whether red_imp could be dropped
1151 -- NOTE: currently the test does not warn about
1154 -- even if the same underlying 'x' is involved, because dropping
1155 -- either import would change the qualified names in scope (M.x, N.x)
1156 -- But if the qualified names aren't used, the import is indeed redundant
1157 -- Sadly we don't know that. Oh well.
1158 covers red_imp@(ImpSpec { is_decl = red_decl, is_item = red_item })
1159 cov_imp@(ImpSpec { is_decl = cov_decl, is_item = cov_item })
1160 | red_loc == cov_loc
1161 = False -- Ignore diagonal elements
1162 | not (is_as red_decl == is_as cov_decl)
1163 = False -- They bring into scope different qualified names
1164 | not (is_qual red_decl) && is_qual cov_decl
1165 = False -- Covering one doesn't bring unqualified name into scope
1167 = not cov_selective -- Redundant one is selective and covering one isn't
1168 || red_later -- Both are explicit; tie-break using red_later
1170 = not cov_selective -- Neither import is selective
1171 && (is_mod red_decl == is_mod cov_decl) -- They import the same module
1172 && red_later -- Tie-break
1174 red_loc = importSpecLoc red_imp
1175 cov_loc = importSpecLoc cov_imp
1176 red_later = red_loc > cov_loc
1177 cov_selective = selectiveImpItem cov_item
1178 red_selective = selectiveImpItem red_item
1180 selectiveImpItem :: ImpItemSpec -> Bool
1181 selectiveImpItem ImpAll = False
1182 selectiveImpItem (ImpSome {}) = True
1184 -- ToDo: deal with original imports with 'qualified' and 'as M' clauses
1185 printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports
1187 printMinimalImports imps
1188 = ifOptM Opt_D_dump_minimal_imports $ do {
1190 mod_ies <- mappM to_ies (fmToList imps) ;
1191 this_mod <- getModule ;
1192 rdr_env <- getGlobalRdrEnv ;
1193 ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ;
1194 printForUser h (mkPrintUnqualified rdr_env)
1195 (vcat (map ppr_mod_ie mod_ies)) })
1198 mkFilename this_mod = moduleNameString (moduleName this_mod) ++ ".imports"
1199 ppr_mod_ie (mod_name, ies)
1200 | mod_name == moduleName pRELUDE
1202 | null ies -- Nothing except instances comes from here
1203 = ptext SLIT("import") <+> ppr mod_name <> ptext SLIT("() -- Instances only")
1205 = ptext SLIT("import") <+> ppr mod_name <>
1206 parens (fsep (punctuate comma (map ppr ies)))
1208 to_ies (mod, avail_env) = do ies <- mapM to_ie (availEnvElts avail_env)
1211 to_ie :: AvailInfo -> RnM (IE Name)
1212 -- The main trick here is that if we're importing all the constructors
1213 -- we want to say "T(..)", but if we're importing only a subset we want
1214 -- to say "T(A,B,C)". So we have to find out what the module exports.
1215 to_ie (Avail n) = returnM (IEVar n)
1216 to_ie (AvailTC n [m]) = ASSERT( n==m )
1217 returnM (IEThingAbs n)
1218 to_ie (AvailTC n ns)
1219 = loadSrcInterface doc n_mod False `thenM` \ iface ->
1220 case [xs | (m,as) <- mi_exports iface,
1221 moduleName m == n_mod,
1223 x == nameOccName n] of
1224 [xs] | all_used xs -> returnM (IEThingAll n)
1225 | otherwise -> returnM (IEThingWith n (filter (/= n) ns))
1226 other -> pprTrace "to_ie" (ppr n <+> ppr n_mod <+> ppr other) $
1229 all_used avail_occs = all (`elem` map nameOccName ns) avail_occs
1230 doc = text "Compute minimal imports from" <+> ppr n
1231 n_mod = moduleName (nameModule n)
1235 %************************************************************************
1239 %************************************************************************
1242 badImportItemErr iface decl_spec ie
1243 = sep [ptext SLIT("Module"), quotes (ppr (is_mod decl_spec)), source_import,
1244 ptext SLIT("does not export"), quotes (ppr ie)]
1246 source_import | mi_boot iface = ptext SLIT("(hi-boot interface)")
1249 illegalImportItemErr = ptext SLIT("Illegal import item")
1251 dodgyImportWarn item = dodgyMsg (ptext SLIT("import")) item
1252 dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) item
1255 = sep [ ptext SLIT("The") <+> kind <+> ptext SLIT("item") <+> quotes (ppr (IEThingAll tc)),
1256 ptext SLIT("suggests that") <+> quotes (ppr tc) <+> ptext SLIT("has constructor or class methods"),
1257 ptext SLIT("but it has none; it is a type synonym or abstract type or class") ]
1260 = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (ppr mod)]
1262 exportItemErr export_item
1263 = sep [ ptext SLIT("The export item") <+> quotes (ppr export_item),
1264 ptext SLIT("attempts to export constructors or class methods that are not visible here") ]
1266 typeItemErr name wherestr
1267 = sep [ ptext SLIT("Using 'type' tag on") <+> quotes (ppr name) <+> wherestr,
1268 ptext SLIT("Use -findexed-types to enable this extension") ]
1270 exportClashErr global_env name1 name2 ie1 ie2
1271 = vcat [ ptext SLIT("Conflicting exports for") <+> quotes (ppr occ) <> colon
1272 , ppr_export ie1 name1
1273 , ppr_export ie2 name2 ]
1275 occ = nameOccName name1
1276 ppr_export ie name = nest 2 (quotes (ppr ie) <+> ptext SLIT("exports") <+>
1277 quotes (ppr name) <+> pprNameProvenance (get_gre name))
1279 -- get_gre finds a GRE for the Name, so that we can show its provenance
1281 = case lookupGRE_Name global_env name of
1283 [] -> pprPanic "exportClashErr" (ppr name)
1285 addDupDeclErr :: Name -> Name -> TcRn ()
1286 addDupDeclErr name_a name_b
1287 = addErrAt (srcLocSpan loc2) $
1288 vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr name1),
1289 ptext SLIT("Declared at:") <+> vcat [ppr (nameSrcLoc name1), ppr loc2]]
1291 loc2 = nameSrcLoc name2
1292 (name1,name2) | nameSrcLoc name_a > nameSrcLoc name_b = (name_b,name_a)
1293 | otherwise = (name_a,name_b)
1294 -- Report the error at the later location
1296 dupExportWarn occ_name ie1 ie2
1297 = hsep [quotes (ppr occ_name),
1298 ptext SLIT("is exported by"), quotes (ppr ie1),
1299 ptext SLIT("and"), quotes (ppr ie2)]
1302 = hsep [ptext SLIT("Duplicate"),
1303 quotes (ptext SLIT("Module") <+> ppr mod),
1304 ptext SLIT("in export list")]
1306 moduleDeprec mod txt
1307 = sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"),