2 % (c) The GRASP Project, Glasgow University, 1992-1998
4 \section[Rename]{Renaming and dependency analysis passes}
8 renameModule, renameStmt, renameRdrName, mkGlobalContext,
9 closeIfaceDecls, checkOldIface, slurpIface
12 #include "HsVersions.h"
15 import RdrHsSyn ( RdrNameHsModule, RdrNameHsDecl, RdrNameDeprecation,
16 RdrNameTyClDecl, RdrNameRuleDecl, RdrNameInstDecl, RdrNameImportDecl,
19 import RnHsSyn ( RenamedHsDecl, RenamedTyClDecl, RenamedRuleDecl, RenamedInstDecl,
21 instDeclFVs, tyClDeclFVs, ruleDeclFVs
24 import CmdLineOpts ( DynFlags, DynFlag(..) )
26 import RnExpr ( rnStmt )
27 import RnNames ( getGlobalNames, exportsFromAvail )
28 import RnSource ( rnSourceDecls, rnTyClDecl, rnIfaceRuleDecl, rnInstDecl )
29 import RnIfaces ( slurpImpDecls, mkImportInfo, recordLocalSlurps,
31 RecompileRequired, outOfDate, recompileRequired
33 import RnHiFiles ( readIface, loadInterface,
34 loadExports, loadFixDecls, loadDeprecs,
36 import RnEnv ( availsToNameSet,
37 unitAvailEnv, availEnvElts, availNames,
38 plusAvailEnv, groupAvails, warnUnusedImports,
39 warnUnusedLocalBinds, warnUnusedModules,
40 lookupSrcName, getImplicitStmtFVs,
41 getImplicitModuleFVs, newGlobalName, unQualInScope,
42 ubiquitousNames, lookupOccRn,
43 plusGlobalRdrEnv, mkGlobalRdrEnv
45 import Module ( Module, ModuleName, WhereFrom(..),
46 moduleNameUserString, moduleName,
49 import Name ( Name, nameModule )
52 import RdrName ( foldRdrEnv, isQual )
53 import PrelNames ( iNTERACTIVE, pRELUDE_Name )
54 import ErrUtils ( dumpIfSet, dumpIfSet_dyn, showPass,
55 printErrorsAndWarnings, errorsFound )
56 import Bag ( bagToList )
57 import FiniteMap ( FiniteMap, fmToList, emptyFM, lookupFM,
58 addToFM_C, elemFM, addToFM
60 import Maybes ( maybeToBool, catMaybes )
62 import IO ( openFile, IOMode(..) )
63 import HscTypes -- lots of it
64 import List ( partition, nub )
68 %*********************************************************
70 \subsection{The main wrappers}
72 %*********************************************************
75 renameModule :: DynFlags
76 -> HomeIfaceTable -> HomeSymbolTable
77 -> PersistentCompilerState
78 -> Module -> RdrNameHsModule
79 -> IO (PersistentCompilerState, PrintUnqualified,
80 Maybe (IsExported, ModIface, [RenamedHsDecl]))
81 -- Nothing => some error occurred in the renamer
83 renameModule dflags hit hst pcs this_module rdr_module
84 = renameSource dflags hit hst pcs this_module $
85 rename this_module rdr_module
89 renameStmt :: DynFlags
90 -> HomeIfaceTable -> HomeSymbolTable
91 -> PersistentCompilerState
93 -> RdrNameStmt -- parsed stmt
94 -> IO ( PersistentCompilerState,
96 Maybe ([Name], (RenamedStmt, [RenamedHsDecl]))
99 renameStmt dflags hit hst pcs ic stmt
100 = renameSource dflags hit hst pcs iNTERACTIVE $
102 -- load the context module
103 let InteractiveContext{ ic_rn_gbl_env = rdr_env,
104 ic_print_unqual = print_unqual,
105 ic_rn_local_env = local_rdr_env,
106 ic_type_env = type_env } = ic
109 extendTypeEnvRn type_env $
112 initRnMS rdr_env emptyAvailEnv local_rdr_env emptyLocalFixityEnv CmdLineMode (
113 rnStmt stmt $ \ stmt' ->
114 returnRn (([], stmt'), emptyFVs)
115 ) `thenRn` \ ((binders, stmt), fvs) ->
117 -- Bale out if we fail
118 checkErrsRn `thenRn` \ no_errs_so_far ->
119 if not no_errs_so_far then
120 doDump dflags [] stmt [] `thenRn_` returnRn (print_unqual, Nothing)
123 -- Add implicit free vars, and close decls
124 getImplicitStmtFVs `thenRn` \ implicit_fvs ->
125 slurpImpDecls (fvs `plusFV` implicit_fvs) `thenRn` \ decls ->
126 -- NB: an earlier version deleted (rdrEnvElts local_env) from
127 -- the fvs. But (a) that isn't necessary, because previously
128 -- bound things in the local_env will be in the TypeEnv, and
129 -- the renamer doesn't re-slurp such things, and
130 -- (b) it's WRONG to delete them. Consider in GHCi:
131 -- Mod> let x = e :: T
132 -- Mod> let y = x + 3
133 -- We need to pass 'x' among the fvs to slurpImpDecls, so that
134 -- the latter can see that T is a gate, and hence import the Num T
135 -- instance decl. (See the InTypEnv case in RnIfaces.slurpSourceRefs.)
137 doDump dflags binders stmt decls `thenRn_`
138 returnRn (print_unqual, Just (binders, (stmt, decls)))
141 doDump :: DynFlags -> [Name] -> RenamedStmt -> [RenamedHsDecl]
142 -> RnMG (Either IOError ())
143 doDump dflags bndrs stmt decls
144 = ioToRnM (dumpIfSet_dyn dflags Opt_D_dump_rn "Renamer:"
145 (vcat [text "Binders:" <+> ppr bndrs,
147 vcat (map ppr decls)]))
152 -> HomeIfaceTable -> HomeSymbolTable
153 -> PersistentCompilerState
154 -> InteractiveContext
155 -> [RdrName] -- name to rename
156 -> IO ( PersistentCompilerState,
158 Maybe ([Name], [RenamedHsDecl])
161 renameRdrName dflags hit hst pcs ic rdr_names =
162 renameSource dflags hit hst pcs iNTERACTIVE $
164 -- load the context module
165 let InteractiveContext{ ic_rn_gbl_env = rdr_env,
166 ic_print_unqual = print_unqual,
167 ic_rn_local_env = local_rdr_env,
168 ic_type_env = type_env } = ic
171 extendTypeEnvRn type_env $
173 -- rename the rdr_name
174 initRnMS rdr_env emptyAvailEnv local_rdr_env emptyLocalFixityEnv CmdLineMode
175 (mapRn (tryRn.lookupOccRn) rdr_names) `thenRn` \ maybe_names ->
177 ok_names = [ a | Right a <- maybe_names ]
180 then let errs = head [ e | Left e <- maybe_names ]
181 in setErrsRn errs `thenRn_`
182 doDump dflags ok_names [] `thenRn_`
183 returnRn (print_unqual, Nothing)
186 slurpImpDecls (mkNameSet ok_names) `thenRn` \ decls ->
188 doDump dflags ok_names decls `thenRn_`
189 returnRn (print_unqual, Just (ok_names, decls))
191 doDump :: DynFlags -> [Name] -> [RenamedHsDecl] -> RnMG (Either IOError ())
192 doDump dflags names decls
193 = ioToRnM (dumpIfSet_dyn dflags Opt_D_dump_rn "Renamer:"
194 (vcat [ppr names, text "",
195 vcat (map ppr decls)]))
198 %*********************************************************
200 \subsection{Make up an interactive context}
202 %*********************************************************
206 :: DynFlags -> HomeIfaceTable -> HomeSymbolTable
207 -> PersistentCompilerState
208 -> [Module] -> [Module]
209 -> IO (PersistentCompilerState, PrintUnqualified, Maybe GlobalRdrEnv)
210 mkGlobalContext dflags hit hst pcs toplevs exports
211 = renameSource dflags hit hst pcs iNTERACTIVE $
213 mapRn getTopLevScope toplevs `thenRn` \ toplev_envs ->
214 mapRn getModuleExports exports `thenRn` \ export_envs ->
215 let full_env = foldr plusGlobalRdrEnv emptyRdrEnv
216 (toplev_envs ++ export_envs)
217 print_unqual = unQualInScope full_env
219 checkErrsRn `thenRn` \ no_errs_so_far ->
220 if not no_errs_so_far then
221 returnRn (print_unqual, Nothing)
223 returnRn (print_unqual, Just full_env)
225 contextDoc = text "context for compiling statements"
227 getTopLevScope :: Module -> RnM d GlobalRdrEnv
229 loadInterface contextDoc (moduleName mod) ImportByUser `thenRn` \ iface ->
230 case mi_globals iface of
231 Nothing -> panic "getTopLevScope"
232 Just env -> returnRn env
234 getModuleExports :: Module -> RnM d GlobalRdrEnv
235 getModuleExports mod =
236 loadInterface contextDoc (moduleName mod) ImportByUser `thenRn` \ iface ->
237 returnRn (foldl add emptyRdrEnv (mi_exports iface))
239 prov_fn n = NonLocalDef ImplicitImport
240 add env (mod,avails) =
241 plusGlobalRdrEnv env (mkGlobalRdrEnv mod True prov_fn avails NoDeprecs)
244 %*********************************************************
246 \subsection{Slurp in a whole module eagerly}
248 %*********************************************************
252 :: DynFlags -> HomeIfaceTable -> HomeSymbolTable
253 -> PersistentCompilerState -> Module
254 -> IO (PersistentCompilerState, PrintUnqualified,
255 Maybe ([Name], [RenamedHsDecl]))
256 slurpIface dflags hit hst pcs mod =
257 renameSource dflags hit hst pcs iNTERACTIVE $
259 let mod_name = moduleName mod
261 loadInterface contextDoc mod_name ImportByUser `thenRn` \ iface ->
262 let fvs = availsToNameSet [ avail | (mn,avails) <- mi_exports iface,
265 slurpImpDecls fvs `thenRn` \ rn_imp_decls ->
266 returnRn (alwaysQualify, Just (nameSetToList fvs, rn_imp_decls))
269 %*********************************************************
271 \subsection{The main function: rename}
273 %*********************************************************
276 renameSource :: DynFlags
277 -> HomeIfaceTable -> HomeSymbolTable
278 -> PersistentCompilerState
280 -> RnMG (PrintUnqualified, Maybe r)
281 -> IO (PersistentCompilerState, PrintUnqualified, Maybe r)
282 -- Nothing => some error occurred in the renamer
284 renameSource dflags hit hst old_pcs this_module thing_inside
285 = do { showPass dflags "Renamer"
287 -- Initialise the renamer monad
288 ; (new_pcs, msgs, (print_unqual, maybe_rn_stuff))
289 <- initRn dflags hit hst old_pcs this_module thing_inside
291 -- Print errors from renaming
292 ; printErrorsAndWarnings print_unqual msgs ;
294 -- Return results. No harm in updating the PCS
295 ; if errorsFound msgs then
296 return (new_pcs, print_unqual, Nothing)
298 return (new_pcs, print_unqual, maybe_rn_stuff)
303 rename :: Module -> RdrNameHsModule
304 -> RnMG (PrintUnqualified, Maybe (IsExported, ModIface, [RenamedHsDecl]))
305 rename this_module contents@(HsModule _ _ exports imports local_decls mod_deprec loc)
308 -- FIND THE GLOBAL NAME ENVIRONMENT
309 getGlobalNames this_module contents `thenRn` \ (gbl_env, local_gbl_env,
310 (mod_avail_env, global_avail_env)) ->
312 print_unqualified = unQualInScope gbl_env
314 full_avail_env :: NameEnv AvailInfo
315 -- The domain of global_avail_env is just the 'major' things;
316 -- variables, type constructors, classes.
317 -- E.g. Functor |-> Functor( Functor, fmap )
318 -- The domain of full_avail_env is everything in scope
319 -- E.g. Functor |-> Functor( Functor, fmap )
320 -- fmap |-> Functor( Functor, fmap )
322 -- This filled-out avail_env is needed to generate
323 -- exports (mkExportAvails), and for generating minimal
324 -- exports (reportUnusedNames)
325 full_avail_env = mkNameEnv [ (name,avail)
326 | avail <- availEnvElts global_avail_env,
327 name <- availNames avail]
329 -- Exit if we've found any errors
330 checkErrsRn `thenRn` \ no_errs_so_far ->
331 if not no_errs_so_far then
332 -- Found errors already, so exit now
333 rnDump [] [] `thenRn_`
334 returnRn (print_unqualified, Nothing)
337 -- PROCESS EXPORT LIST
338 exportsFromAvail mod_name exports mod_avail_env
339 full_avail_env gbl_env `thenRn` \ export_avails ->
341 traceRn (text "Local top-level environment" $$
342 nest 4 (pprGlobalRdrEnv local_gbl_env)) `thenRn_`
344 -- DEAL WITH DEPRECATIONS
345 rnDeprecs local_gbl_env mod_deprec
346 [d | DeprecD d <- local_decls] `thenRn` \ my_deprecs ->
348 -- DEAL WITH LOCAL FIXITIES
349 fixitiesFromLocalDecls local_gbl_env local_decls `thenRn` \ local_fixity_env ->
352 rnSourceDecls gbl_env global_avail_env
353 local_fixity_env local_decls `thenRn` \ (rn_local_decls, source_fvs) ->
355 -- EXIT IF ERRORS FOUND
356 -- We exit here if there are any errors in the source, *before*
357 -- we attempt to slurp the decls from the interfaces, otherwise
358 -- the slurped decls may get lost when we return up the stack
359 -- to hscMain/hscExpr.
360 checkErrsRn `thenRn` \ no_errs_so_far ->
361 if not no_errs_so_far then
362 -- Found errors already, so exit now
363 rnDump [] rn_local_decls `thenRn_`
364 returnRn (print_unqualified, Nothing)
367 -- SLURP IN ALL THE NEEDED DECLARATIONS
368 -- Find out what re-bindable names to use for desugaring
369 getImplicitModuleFVs mod_name rn_local_decls `thenRn` \ implicit_fvs ->
371 export_fvs = availsToNameSet export_avails
372 source_fvs2 = source_fvs `plusFV` export_fvs
373 -- The export_fvs make the exported names look just as if they
374 -- occurred in the source program. For the reasoning, see the
375 -- comments with RnIfaces.mkImportInfo
376 -- It also helps reportUnusedNames, which of course must not complain
377 -- that 'f' isn't mentioned if it is mentioned in the export list
379 source_fvs3 = implicit_fvs `plusFV` source_fvs2
380 -- It's important to do the "plus" this way round, so that
381 -- when compiling the prelude, locally-defined (), Bool, etc
382 -- override the implicit ones.
385 traceRn (text "Source FVs:" <+> fsep (map ppr (nameSetToList source_fvs3))) `thenRn_`
386 slurpImpDecls source_fvs3 `thenRn` \ rn_imp_decls ->
387 rnDump rn_imp_decls rn_local_decls `thenRn_`
389 -- GENERATE THE VERSION/USAGE INFO
390 mkImportInfo mod_name imports `thenRn` \ my_usages ->
392 -- BUILD THE MODULE INTERFACE
394 -- We record fixities even for things that aren't exported,
395 -- so that we can change into the context of this moodule easily
396 fixities = mkNameEnv [ (name, fixity)
397 | FixitySig name fixity loc <- nameEnvElts local_fixity_env
400 -- Sort the exports to make them easier to compare for versions
401 my_exports = groupAvails this_module export_avails
403 final_decls = rn_local_decls ++ rn_imp_decls
405 mod_iface = ModIface { mi_module = this_module,
406 mi_version = initialVersionInfo,
407 mi_usages = my_usages,
409 mi_orphan = panic "is_orphan",
410 mi_exports = my_exports,
411 mi_globals = Just gbl_env,
412 mi_fixities = fixities,
413 mi_deprecs = my_deprecs,
414 mi_decls = panic "mi_decls"
417 is_exported name = name `elemNameSet` exported_names
418 exported_names = availsToNameSet export_avails
421 -- REPORT UNUSED NAMES, AND DEBUG DUMP
422 reportUnusedNames mod_iface print_unqualified
423 imports full_avail_env gbl_env
424 source_fvs2 rn_imp_decls `thenRn_`
425 -- NB: source_fvs2: include exports (else we get bogus
426 -- warnings of unused things) but not implicit FVs.
428 returnRn (print_unqualified, Just (is_exported, mod_iface, final_decls))
430 mod_name = moduleName this_module
435 %*********************************************************
437 \subsection{Fixities}
439 %*********************************************************
442 fixitiesFromLocalDecls :: GlobalRdrEnv -> [RdrNameHsDecl] -> RnMG LocalFixityEnv
443 fixitiesFromLocalDecls gbl_env decls
444 = foldlRn getFixities emptyNameEnv decls `thenRn` \ env ->
445 traceRn (text "fixity env" <+> vcat (map ppr (nameEnvElts env))) `thenRn_`
448 getFixities :: LocalFixityEnv -> RdrNameHsDecl -> RnMG LocalFixityEnv
449 getFixities acc (FixD fix)
452 getFixities acc (TyClD (ClassDecl { tcdSigs = sigs}))
453 = foldlRn fix_decl acc [sig | FixSig sig <- sigs]
454 -- Get fixities from class decl sigs too.
455 getFixities acc other_decl
458 fix_decl acc sig@(FixitySig rdr_name fixity loc)
459 = -- Check for fixity decl for something not declared
461 lookupSrcName gbl_env rdr_name `thenRn` \ name ->
463 -- Check for duplicate fixity decl
464 case lookupNameEnv acc name of
465 Just (FixitySig _ _ loc') -> addErrRn (dupFixityDecl rdr_name loc loc') `thenRn_`
468 Nothing -> returnRn (extendNameEnv acc name (FixitySig name fixity loc))
472 %*********************************************************
474 \subsection{Deprecations}
476 %*********************************************************
478 For deprecations, all we do is check that the names are in scope.
479 It's only imported deprecations, dealt with in RnIfaces, that we
480 gather them together.
483 rnDeprecs :: GlobalRdrEnv -> Maybe DeprecTxt
484 -> [RdrNameDeprecation] -> RnMG Deprecations
485 rnDeprecs gbl_env Nothing []
488 rnDeprecs gbl_env (Just txt) decls
489 = mapRn (addErrRn . badDeprec) decls `thenRn_`
490 returnRn (DeprecAll txt)
492 rnDeprecs gbl_env Nothing decls
493 = mapRn rn_deprec decls `thenRn` \ pairs ->
494 returnRn (DeprecSome (mkNameEnv (catMaybes pairs)))
496 rn_deprec (Deprecation rdr_name txt loc)
498 lookupSrcName gbl_env rdr_name `thenRn` \ name ->
499 returnRn (Just (name, (name,txt)))
503 %************************************************************************
505 \subsection{Grabbing the old interface file and checking versions}
507 %************************************************************************
510 checkOldIface :: GhciMode
512 -> HomeIfaceTable -> HomeSymbolTable
513 -> PersistentCompilerState
515 -> Bool -- Source unchanged
516 -> Maybe ModIface -- Old interface from compilation manager, if any
517 -> IO (PersistentCompilerState, Bool, (RecompileRequired, Maybe ModIface))
518 -- True <=> errors happened
520 checkOldIface ghci_mode dflags hit hst pcs iface_path source_unchanged maybe_iface
521 = runRn dflags hit hst pcs (panic "Bogus module") $
523 -- CHECK WHETHER THE SOURCE HAS CHANGED
524 ( if not source_unchanged then
525 traceHiDiffsRn (nest 4 (text "Source file changed or recompilation check turned off"))
526 else returnRn () ) `thenRn_`
528 -- If the source has changed and we're in interactive mode, avoid reading
529 -- an interface; just return the one we might have been supplied with.
530 if ghci_mode == Interactive && not source_unchanged then
531 returnRn (outOfDate, maybe_iface)
535 Just old_iface -> -- Use the one we already have
536 setModuleRn (mi_module old_iface) (check_versions old_iface)
538 Nothing -- try and read it from a file
539 -> readIface iface_path `thenRn` \ read_result ->
541 Left err -> -- Old interface file not found, or garbled; give up
543 text "Cannot read old interface file:"
544 $$ nest 4 err) `thenRn_`
545 returnRn (outOfDate, Nothing)
548 -> setModuleRn (pi_mod parsed_iface) $
549 loadOldIface parsed_iface `thenRn` \ m_iface ->
550 check_versions m_iface
552 check_versions :: ModIface -> RnMG (RecompileRequired, Maybe ModIface)
554 | not source_unchanged
555 = returnRn (outOfDate, Just iface)
558 recompileRequired iface_path iface `thenRn` \ recompile ->
559 returnRn (recompile, Just iface)
562 I think the following function should now have a more representative name,
566 loadOldIface :: ParsedIface -> RnMG ModIface
568 loadOldIface parsed_iface
569 = let iface = parsed_iface
573 loadHomeDecls (pi_decls iface) `thenRn` \ decls ->
574 loadHomeRules (pi_rules iface) `thenRn` \ rules ->
575 loadHomeInsts (pi_insts iface) `thenRn` \ insts ->
576 returnRn (decls, rules, insts)
578 `thenRn` \ ((decls_vers, new_decls), (rule_vers, new_rules), new_insts) ->
580 mapRn loadHomeUsage (pi_usages iface) `thenRn` \ usages ->
581 loadExports (pi_exports iface) `thenRn` \ (export_vers, avails) ->
582 loadFixDecls mod (pi_fixity iface) `thenRn` \ fix_env ->
583 loadDeprecs mod (pi_deprecs iface) `thenRn` \ deprec_env ->
585 version = VersionInfo { vers_module = pi_vers iface,
586 vers_exports = export_vers,
587 vers_rules = rule_vers,
588 vers_decls = decls_vers }
590 decls = mkIfaceDecls new_decls new_rules new_insts
592 mod_iface = ModIface { mi_module = mod, mi_version = version,
593 mi_exports = avails, mi_usages = usages,
594 mi_boot = False, mi_orphan = pi_orphan iface,
595 mi_fixities = fix_env, mi_deprecs = deprec_env,
604 loadHomeDecls :: [(Version, RdrNameTyClDecl)]
605 -> RnMS (NameEnv Version, [RenamedTyClDecl])
606 loadHomeDecls decls = foldlRn loadHomeDecl (emptyNameEnv, []) decls
608 loadHomeDecl :: (NameEnv Version, [RenamedTyClDecl])
609 -> (Version, RdrNameTyClDecl)
610 -> RnMS (NameEnv Version, [RenamedTyClDecl])
611 loadHomeDecl (version_map, decls) (version, decl)
612 = rnTyClDecl decl `thenRn` \ decl' ->
613 returnRn (extendNameEnv version_map (tyClDeclName decl') version, decl':decls)
616 loadHomeRules :: (Version, [RdrNameRuleDecl])
617 -> RnMS (Version, [RenamedRuleDecl])
618 loadHomeRules (version, rules)
619 = mapRn rnIfaceRuleDecl rules `thenRn` \ rules' ->
620 returnRn (version, rules')
623 loadHomeInsts :: [RdrNameInstDecl]
624 -> RnMS [RenamedInstDecl]
625 loadHomeInsts insts = mapRn rnInstDecl insts
628 loadHomeUsage :: ImportVersion OccName
629 -> RnMG (ImportVersion Name)
630 loadHomeUsage (mod_name, orphans, is_boot, whats_imported)
631 = rn_imps whats_imported `thenRn` \ whats_imported' ->
632 returnRn (mod_name, orphans, is_boot, whats_imported')
634 rn_imps NothingAtAll = returnRn NothingAtAll
635 rn_imps (Everything v) = returnRn (Everything v)
636 rn_imps (Specifically mv ev items rv) = mapRn rn_imp items `thenRn` \ items' ->
637 returnRn (Specifically mv ev items' rv)
638 rn_imp (occ,vers) = newGlobalName mod_name occ `thenRn` \ name ->
644 %*********************************************************
646 \subsection{Closing up the interface decls}
648 %*********************************************************
650 Suppose we discover we don't need to recompile. Then we start from the
651 IfaceDecls in the ModIface, and fluff them up by sucking in all the decls they need.
654 closeIfaceDecls :: DynFlags
655 -> HomeIfaceTable -> HomeSymbolTable
656 -> PersistentCompilerState
657 -> ModIface -- Get the decls from here
658 -> IO (PersistentCompilerState, Bool, [RenamedHsDecl])
659 -- True <=> errors happened
660 closeIfaceDecls dflags hit hst pcs
661 mod_iface@(ModIface { mi_module = mod, mi_decls = iface_decls })
662 = runRn dflags hit hst pcs mod $
665 rule_decls = dcl_rules iface_decls
666 inst_decls = dcl_insts iface_decls
667 tycl_decls = dcl_tycl iface_decls
668 decls = map RuleD rule_decls ++
669 map InstD inst_decls ++
671 needed = unionManyNameSets (map ruleDeclFVs rule_decls) `unionNameSets`
672 unionManyNameSets (map instDeclFVs inst_decls) `unionNameSets`
673 unionManyNameSets (map tyClDeclFVs tycl_decls)
674 local_names = foldl add emptyNameSet tycl_decls
675 add names decl = addListToNameSet names (map fst (tyClDeclSysNames decl ++ tyClDeclNames decl))
678 recordLocalSlurps local_names `thenRn_`
680 -- Do the transitive closure
681 closeDecls decls (needed `plusFV` implicit_fvs) `thenRn` \closed_decls ->
682 rnDump [] closed_decls `thenRn_`
683 returnRn closed_decls
685 implicit_fvs = ubiquitousNames -- Data type decls with record selectors,
686 -- which may appear in the decls, need unpackCString
687 -- and friends. It's easier to just grab them right now.
690 %*********************************************************
692 \subsection{Unused names}
694 %*********************************************************
697 reportUnusedNames :: ModIface -> PrintUnqualified
698 -> [RdrNameImportDecl]
701 -> NameSet -- Used in this module
704 reportUnusedNames my_mod_iface unqual imports avail_env gbl_env
705 used_names imported_decls
706 = warnUnusedModules unused_imp_mods `thenRn_`
707 warnUnusedLocalBinds bad_locals `thenRn_`
708 warnUnusedImports bad_imp_names `thenRn_`
709 printMinimalImports this_mod unqual minimal_imports
711 this_mod = mi_module my_mod_iface
713 -- Now, a use of C implies a use of T,
714 -- if C was brought into scope by T(..) or T(C)
715 really_used_names = used_names `unionNameSets`
716 mkNameSet [ parent_name
717 | sub_name <- nameSetToList used_names
719 -- Usually, every used name will appear in avail_env, but there
720 -- is one time when it doesn't: tuples and other built in syntax. When you
721 -- write (a,b) that gives rise to a *use* of "(,)", so that the
722 -- instances will get pulled in, but the tycon "(,)" isn't actually
723 -- in scope. Also, (-x) gives rise to an implicit use of 'negate';
724 -- similarly, 3.5 gives rise to an implcit use of :%
725 -- Hence the silent 'False' in all other cases
727 , Just parent_name <- [case lookupNameEnv avail_env sub_name of
728 Just (AvailTC n _) -> Just n
732 -- Collect the defined names from the in-scope environment
733 -- Look for the qualified ones only, else get duplicates
734 defined_names :: [GlobalRdrElt]
735 defined_names = foldRdrEnv add [] gbl_env
736 add rdr_name ns acc | isQual rdr_name = ns ++ acc
739 defined_and_used, defined_but_not_used :: [GlobalRdrElt]
740 (defined_and_used, defined_but_not_used) = partition used defined_names
741 used (GRE name _ _) = name `elemNameSet` really_used_names
743 -- Filter out the ones only defined implicitly
745 bad_locals = [n | (GRE n LocalDef _) <- defined_but_not_used]
747 bad_imp_names :: [(Name,Provenance)]
748 bad_imp_names = [(n,p) | GRE n p@(NonLocalDef (UserImport mod _ True)) _ <- defined_but_not_used,
749 not (module_unused mod)]
751 -- inst_mods are directly-imported modules that
752 -- contain instance decl(s) that the renamer decided to suck in
753 -- It's not necessarily redundant to import such modules.
759 -- The import M() is not *necessarily* redundant, even if
760 -- we suck in no instance decls from M (e.g. it contains
761 -- no instance decls, or This contains no code). It may be
762 -- that we import M solely to ensure that M's orphan instance
763 -- decls (or those in its imports) are visible to people who
764 -- import This. Sigh.
765 -- There's really no good way to detect this, so the error message
766 -- in RnEnv.warnUnusedModules is weakened instead
767 inst_mods :: [ModuleName]
768 inst_mods = [m | InstD (InstDecl _ _ _ (Just dfun) _) <- imported_decls,
769 let m = moduleName (nameModule dfun),
770 m `elem` direct_import_mods
773 -- To figure out the minimal set of imports, start with the things
774 -- that are in scope (i.e. in gbl_env). Then just combine them
775 -- into a bunch of avails, so they are properly grouped
776 minimal_imports :: FiniteMap ModuleName AvailEnv
777 minimal_imports0 = emptyFM
778 minimal_imports1 = foldr add_name minimal_imports0 defined_and_used
779 minimal_imports = foldr add_inst_mod minimal_imports1 inst_mods
781 -- We've carefully preserved the provenance so that we can
782 -- construct minimal imports that import the name by (one of)
783 -- the same route(s) as the programmer originally did.
784 add_name (GRE n (NonLocalDef (UserImport m _ _)) _) acc = addToFM_C plusAvailEnv acc (moduleName m)
785 (unitAvailEnv (mk_avail n))
786 add_name (GRE n other_prov _) acc = acc
788 mk_avail n = case lookupNameEnv avail_env n of
789 Just (AvailTC m _) | n==m -> AvailTC n [n]
790 | otherwise -> AvailTC m [n,m]
791 Just avail -> Avail n
792 Nothing -> pprPanic "mk_avail" (ppr n)
795 | m `elemFM` acc = acc -- We import something already
796 | otherwise = addToFM acc m emptyAvailEnv
797 -- Add an empty collection of imports for a module
798 -- from which we have sucked only instance decls
800 direct_import_mods :: [ModuleName]
801 direct_import_mods = nub [m | ImportDecl m _ _ _ _ _ <- imports]
803 -- unused_imp_mods are the directly-imported modules
804 -- that are not mentioned in minimal_imports
805 unused_imp_mods = [m | m <- direct_import_mods,
806 not (maybeToBool (lookupFM minimal_imports m)),
809 module_unused :: Module -> Bool
810 module_unused mod = moduleName mod `elem` unused_imp_mods
813 -- ToDo: deal with original imports with 'qualified' and 'as M' clauses
814 printMinimalImports :: Module -- This module
816 -> FiniteMap ModuleName AvailEnv -- Minimal imports
818 printMinimalImports this_mod unqual imps
819 = ifOptRn Opt_D_dump_minimal_imports $
821 mapRn to_ies (fmToList imps) `thenRn` \ mod_ies ->
822 ioToRnM (do { h <- openFile filename WriteMode ;
823 printForUser h unqual (vcat (map ppr_mod_ie mod_ies))
827 filename = moduleNameUserString (moduleName this_mod) ++ ".imports"
828 ppr_mod_ie (mod_name, ies)
829 | mod_name == pRELUDE_Name
832 = ptext SLIT("import") <+> ppr mod_name <>
833 parens (fsep (punctuate comma (map ppr ies)))
835 to_ies (mod, avail_env) = mapRn to_ie (availEnvElts avail_env) `thenRn` \ ies ->
838 to_ie :: AvailInfo -> RnMG (IE Name)
839 -- The main trick here is that if we're importing all the constructors
840 -- we want to say "T(..)", but if we're importing only a subset we want
841 -- to say "T(A,B,C)". So we have to find out what the module exports.
842 to_ie (Avail n) = returnRn (IEVar n)
843 to_ie (AvailTC n [m]) = ASSERT( n==m )
844 returnRn (IEThingAbs n)
846 = loadInterface (text "Compute minimal imports from" <+> ppr n_mod)
847 n_mod ImportBySystem `thenRn` \ iface ->
848 case [xs | (m,as) <- mi_exports iface,
852 [xs] | all (`elem` ns) xs -> returnRn (IEThingAll n)
853 | otherwise -> returnRn (IEThingWith n (filter (/= n) ns))
854 other -> pprTrace "to_ie" (ppr n <+> ppr (nameModule n) <+> ppr other) $
857 n_mod = moduleName (nameModule n)
859 rnDump :: [RenamedHsDecl] -- Renamed imported decls
860 -> [RenamedHsDecl] -- Renamed local decls
862 rnDump imp_decls local_decls
863 = doptRn Opt_D_dump_rn_trace `thenRn` \ dump_rn_trace ->
864 doptRn Opt_D_dump_rn_stats `thenRn` \ dump_rn_stats ->
865 doptRn Opt_D_dump_rn `thenRn` \ dump_rn ->
866 getIfacesRn `thenRn` \ ifaces ->
868 ioToRnM (do { dumpIfSet (dump_rn_trace || dump_rn_stats || dump_rn)
870 (getRnStats imp_decls ifaces) ;
872 dumpIfSet dump_rn "Renamer:"
873 (vcat (map ppr (local_decls ++ imp_decls)))
880 %*********************************************************
882 \subsection{Statistics}
884 %*********************************************************
887 getRnStats :: [RenamedHsDecl] -> Ifaces -> SDoc
888 getRnStats imported_decls ifaces
889 = hcat [text "Renamer stats: ", stats]
891 n_mods = length [() | _ <- moduleEnvElts (iPIT ifaces)]
892 -- This is really only right for a one-shot compile
894 (decls_map, n_decls_slurped) = iDecls ifaces
896 n_decls_left = length [decl | (avail, True, (_,decl)) <- nameEnvElts decls_map
897 -- Data, newtype, and class decls are in the decls_fm
898 -- under multiple names; the tycon/class, and each
899 -- constructor/class op too.
900 -- The 'True' selects just the 'main' decl
903 (insts_left, n_insts_slurped) = iInsts ifaces
904 n_insts_left = length (bagToList insts_left)
906 (rules_left, n_rules_slurped) = iRules ifaces
907 n_rules_left = length (bagToList rules_left)
910 [int n_mods <+> text "interfaces read",
911 hsep [ int n_decls_slurped, text "type/class/variable imported, out of",
912 int (n_decls_slurped + n_decls_left), text "read"],
913 hsep [ int n_insts_slurped, text "instance decls imported, out of",
914 int (n_insts_slurped + n_insts_left), text "read"],
915 hsep [ int n_rules_slurped, text "rule decls imported, out of",
916 int (n_rules_slurped + n_rules_left), text "read"]
921 %************************************************************************
923 \subsection{Errors and warnings}
925 %************************************************************************
928 dupFixityDecl rdr_name loc1 loc2
929 = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name),
930 ptext SLIT("at ") <+> ppr loc1,
931 ptext SLIT("and") <+> ppr loc2]
934 = sep [ptext SLIT("Illegal deprecation when whole module is deprecated"),