2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
5 \section[TcMovectle]{Typechecking a whole module}
10 tcRnStmt, tcRnExpr, tcRnType,
23 import {-# SOURCE #-} TcSplice ( tcSpliceDecls )
40 import TcType ( tidyTopType )
76 import TcType ( orphNamesOfDFunHead )
77 import Inst ( tcGetInstEnvs )
78 import Data.List ( sortBy )
81 import TcType ( isUnitTy, isTauTy )
82 import CoreUtils( mkPiTypes )
90 import TidyPgm ( globaliseAndTidyId )
91 import TysWiredIn ( unitTy, mkListTy )
101 #include "HsVersions.h"
104 %************************************************************************
106 Typecheck and rename a module
108 %************************************************************************
114 -> Bool -- True <=> save renamed syntax
115 -> Located (HsModule RdrName)
116 -> IO (Messages, Maybe TcGblEnv)
118 tcRnModule hsc_env hsc_src save_rn_syntax
119 (L loc (HsModule maybe_mod export_ies
120 import_decls local_decls mod_deprec
122 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
124 let { this_pkg = thisPackage (hsc_dflags hsc_env) ;
125 this_mod = case maybe_mod of
126 Nothing -> mAIN -- 'module M where' is omitted
127 Just (L _ mod) -> mkModule this_pkg mod } ;
130 initTc hsc_env hsc_src save_rn_syntax this_mod $
132 do { -- Deal with imports;
133 tcg_env <- tcRnImports hsc_env this_mod import_decls ;
134 setGblEnv tcg_env $ do {
136 -- Load the hi-boot interface for this module, if any
137 -- We do this now so that the boot_names can be passed
138 -- to tcTyAndClassDecls, because the boot_names are
139 -- automatically considered to be loop breakers
141 -- Do this *after* tcRnImports, so that we know whether
142 -- a module that we import imports us; and hence whether to
143 -- look for a hi-boot file
144 boot_iface <- tcHiBootIface hsc_src this_mod ;
146 -- Rename and type check the declarations
147 traceRn (text "rn1a") ;
148 tcg_env <- if isHsBoot hsc_src then
149 tcRnHsBootDecls local_decls
151 tcRnSrcDecls boot_iface local_decls ;
152 setGblEnv tcg_env $ do {
154 -- Report the use of any deprecated things
155 -- We do this *before* processsing the export list so
156 -- that we don't bleat about re-exporting a deprecated
157 -- thing (especially via 'module Foo' export item)
158 -- That is, only uses in the *body* of the module are complained about
159 traceRn (text "rn3") ;
160 failIfErrsM ; -- finishWarnings crashes sometimes
161 -- as a result of typechecker repairs (e.g. unboundNames)
162 tcg_env <- finishWarnings (hsc_dflags hsc_env) mod_deprec tcg_env ;
164 -- Process the export list
165 traceRn (text "rn4a: before exports");
166 tcg_env <- rnExports (isJust maybe_mod) export_ies tcg_env ;
167 traceRn (text "rn4b: after exportss") ;
169 -- Check that main is exported (must be after rnExports)
170 checkMainExported tcg_env ;
172 -- Compare the hi-boot iface (if any) with the real thing
173 -- Must be done after processing the exports
174 tcg_env <- checkHiBootIface tcg_env boot_iface ;
176 -- The new type env is already available to stuff slurped from
177 -- interface files, via TcEnv.updateGlobalTypeEnv
178 -- It's important that this includes the stuff in checkHiBootIface,
179 -- because the latter might add new bindings for boot_dfuns,
180 -- which may be mentioned in imported unfoldings
182 -- Don't need to rename the Haddock documentation,
183 -- it's not parsed by GHC anymore.
184 tcg_env <- return (tcg_env { tcg_doc_hdr = maybe_doc_hdr }) ;
186 -- Report unused names
187 reportUnusedNames export_ies tcg_env ;
189 -- Dump output and return
196 %************************************************************************
200 %************************************************************************
203 tcRnImports :: HscEnv -> Module -> [LImportDecl RdrName] -> TcM TcGblEnv
204 tcRnImports hsc_env this_mod import_decls
205 = do { (rn_imports, rdr_env, imports,hpc_info) <- rnImports import_decls ;
207 ; let { dep_mods :: ModuleNameEnv (ModuleName, IsBootInterface)
208 ; dep_mods = imp_dep_mods imports
210 -- We want instance declarations from all home-package
211 -- modules below this one, including boot modules, except
212 -- ourselves. The 'except ourselves' is so that we don't
213 -- get the instances from this module's hs-boot file
214 ; want_instances :: ModuleName -> Bool
215 ; want_instances mod = mod `elemUFM` dep_mods
216 && mod /= moduleName this_mod
217 ; (home_insts, home_fam_insts) = hptInstances hsc_env
221 -- Record boot-file info in the EPS, so that it's
222 -- visible to loadHiBootInterface in tcRnSrcDecls,
223 -- and any other incrementally-performed imports
224 ; updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
226 -- Update the gbl env
227 ; updGblEnv ( \ gbl ->
229 tcg_rdr_env = plusOccEnv (tcg_rdr_env gbl) rdr_env,
230 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
231 tcg_rn_imports = rn_imports,
232 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
233 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env gbl)
238 ; traceRn (text "rn1" <+> ppr (imp_dep_mods imports))
239 -- Fail if there are any errors so far
240 -- The error printing (if needed) takes advantage
241 -- of the tcg_env we have now set
242 -- ; traceIf (text "rdr_env: " <+> ppr rdr_env)
245 -- Load any orphan-module and family instance-module
246 -- interfaces, so that their rules and instance decls will be
248 ; loadOrphanModules (imp_orphs imports) False
249 ; loadOrphanModules (imp_finsts imports) True
251 -- Check type-familily consistency
252 ; traceRn (text "rn1: checking family instance consistency")
253 ; let { dir_imp_mods = moduleEnvKeys
256 ; checkFamInstConsistency (imp_finsts imports) dir_imp_mods ;
262 %************************************************************************
264 Type-checking external-core modules
266 %************************************************************************
269 tcRnExtCore :: HscEnv
271 -> IO (Messages, Maybe ModGuts)
272 -- Nothing => some error occurred
274 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
275 -- The decls are IfaceDecls; all names are original names
276 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
278 initTc hsc_env ExtCoreFile False this_mod $ do {
280 let { ldecls = map noLoc decls } ;
282 -- bring the type and class decls into scope
283 -- ToDo: check that this doesn't need to extract the val binds.
284 -- It seems that only the type and class decls need to be in scope below because
285 -- (a) tcTyAndClassDecls doesn't need the val binds, and
286 -- (b) tcExtCoreBindings doesn't need anything
287 -- (in fact, it might not even need to be in the scope of
288 -- this tcg_env at all)
289 avails <- getLocalNonValBinders (mkFakeGroup ldecls) ;
290 tc_envs <- extendGlobalRdrEnvRn avails emptyFsEnv {- no fixity decls -} ;
292 setEnvs tc_envs $ do {
294 (rn_decls, _fvs) <- checkNoErrs $ rnTyClDecls [ldecls] ;
296 -- Dump trace of renaming part
297 rnDump (ppr rn_decls) ;
299 -- Typecheck them all together so that
300 -- any mutually recursive types are done right
301 -- Just discard the auxiliary bindings; they are generated
302 -- only for Haskell source code, and should already be in Core
303 (tcg_env, _aux_binds, _dm_ids) <- tcTyAndClassDecls emptyModDetails rn_decls ;
305 setGblEnv tcg_env $ do {
306 -- Make the new type env available to stuff slurped from interface files
308 -- Now the core bindings
309 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
313 bndrs = bindersOfBinds core_binds ;
314 my_exports = map (Avail . idName) bndrs ;
315 -- ToDo: export the data types also?
318 extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
320 mod_guts = ModGuts { mg_module = this_mod,
322 mg_used_names = emptyNameSet, -- ToDo: compute usage
323 mg_dir_imps = emptyModuleEnv, -- ??
324 mg_deps = noDependencies, -- ??
325 mg_exports = my_exports,
326 mg_types = final_type_env,
327 mg_insts = tcg_insts tcg_env,
328 mg_fam_insts = tcg_fam_insts tcg_env,
329 mg_inst_env = tcg_inst_env tcg_env,
330 mg_fam_inst_env = tcg_fam_inst_env tcg_env,
334 mg_binds = core_binds,
337 mg_rdr_env = emptyGlobalRdrEnv,
338 mg_fix_env = emptyFixityEnv,
339 mg_warns = NoWarnings,
340 mg_foreign = NoStubs,
341 mg_hpc_info = emptyHpcInfo False,
342 mg_modBreaks = emptyModBreaks,
343 mg_vect_info = noVectInfo
346 tcCoreDump mod_guts ;
351 mkFakeGroup :: [LTyClDecl a] -> HsGroup a
352 mkFakeGroup decls -- Rather clumsy; lots of unused fields
353 = emptyRdrGroup { hs_tyclds = [decls] }
357 %************************************************************************
359 Type-checking the top level of a module
361 %************************************************************************
364 tcRnSrcDecls :: ModDetails -> [LHsDecl RdrName] -> TcM TcGblEnv
365 -- Returns the variables free in the decls
366 -- Reason: solely to report unused imports and bindings
367 tcRnSrcDecls boot_iface decls
368 = do { -- Do all the declarations
369 (tc_envs, lie) <- captureConstraints $ tc_rn_src_decls boot_iface decls ;
370 ; traceTc "Tc8" empty ;
374 -- Finish simplifying class constraints
376 -- simplifyTop deals with constant or ambiguous InstIds.
377 -- How could there be ambiguous ones? They can only arise if a
378 -- top-level decl falls under the monomorphism restriction
379 -- and no subsequent decl instantiates its type.
381 -- We do this after checkMain, so that we use the type info
382 -- thaat checkMain adds
384 -- We do it with both global and local env in scope:
385 -- * the global env exposes the instances to simplifyTop
386 -- * the local env exposes the local Ids to simplifyTop,
387 -- so that we get better error messages (monomorphism restriction)
388 new_ev_binds <- simplifyTop lie ;
389 traceTc "Tc9" empty ;
391 failIfErrsM ; -- Don't zonk if there have been errors
392 -- It's a waste of time; and we may get debug warnings
393 -- about strangely-typed TyCons!
395 -- Zonk the final code. This must be done last.
396 -- Even simplifyTop may do some unification.
397 -- This pass also warns about missing type signatures
398 let { (tcg_env, _) = tc_envs
399 ; TcGblEnv { tcg_type_env = type_env,
402 tcg_ev_binds = cur_ev_binds,
403 tcg_imp_specs = imp_specs,
406 tcg_fords = fords } = tcg_env
407 ; all_ev_binds = cur_ev_binds `unionBags` new_ev_binds } ;
409 (bind_ids, ev_binds', binds', fords', imp_specs', rules', vects')
410 <- zonkTopDecls all_ev_binds binds sig_ns rules vects imp_specs fords ;
412 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
413 ; tcg_env' = tcg_env { tcg_binds = binds',
414 tcg_ev_binds = ev_binds',
415 tcg_imp_specs = imp_specs',
418 tcg_fords = fords' } } ;
420 setGlobalTypeEnv tcg_env' final_type_env
423 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
424 -- Loops around dealing with each top level inter-splice group
425 -- in turn, until it's dealt with the entire module
426 tc_rn_src_decls boot_details ds
427 = do { (first_group, group_tail) <- findSplice ds ;
428 -- If ds is [] we get ([], Nothing)
430 -- Deal with decls up to, but not including, the first splice
431 (tcg_env, rn_decls) <- rnTopSrcDecls first_group ;
432 -- rnTopSrcDecls fails if there are any errors
434 (tcg_env, tcl_env) <- setGblEnv tcg_env $
435 tcTopSrcDecls boot_details rn_decls ;
437 -- If there is no splice, we're nearly done
438 setEnvs (tcg_env, tcl_env) $
440 Nothing -> do { tcg_env <- checkMain ; -- Check for `main'
441 return (tcg_env, tcl_env)
445 -- There shouldn't be a splice
446 Just (SpliceDecl {}, _) -> do {
447 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
449 -- If there's a splice, we must carry on
450 Just (SpliceDecl splice_expr _, rest_ds) -> do {
452 -- Rename the splice expression, and get its supporting decls
453 (rn_splice_expr, splice_fvs) <- checkNoErrs (rnLExpr splice_expr) ;
454 -- checkNoErrs: don't typecheck if renaming failed
455 rnDump (ppr rn_splice_expr) ;
457 -- Execute the splice
458 spliced_decls <- tcSpliceDecls rn_splice_expr ;
460 -- Glue them on the front of the remaining decls and loop
461 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
462 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
467 %************************************************************************
469 Compiling hs-boot source files, and
470 comparing the hi-boot interface with the real thing
472 %************************************************************************
475 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
476 tcRnHsBootDecls decls
477 = do { (first_group, group_tail) <- findSplice decls
479 -- Rename the declarations
480 ; (tcg_env, HsGroup {
481 hs_tyclds = tycl_decls,
482 hs_instds = inst_decls,
483 hs_derivds = deriv_decls,
484 hs_fords = for_decls,
485 hs_defds = def_decls,
486 hs_ruleds = rule_decls,
487 hs_vects = vect_decls,
489 hs_valds = val_binds }) <- rnTopSrcDecls first_group
490 ; (gbl_env, lie) <- captureConstraints $ setGblEnv tcg_env $ do {
493 -- Check for illegal declarations
495 Just (SpliceDecl d _, _) -> badBootDecl "splice" d
497 ; mapM_ (badBootDecl "foreign") for_decls
498 ; mapM_ (badBootDecl "default") def_decls
499 ; mapM_ (badBootDecl "rule") rule_decls
500 ; mapM_ (badBootDecl "vect") vect_decls
502 -- Typecheck type/class decls
503 ; traceTc "Tc2" empty
504 ; (tcg_env, aux_binds, dm_ids)
505 <- tcTyAndClassDecls emptyModDetails tycl_decls
506 ; setGblEnv tcg_env $
507 tcExtendIdEnv dm_ids $ do {
509 -- Typecheck instance decls
510 -- Family instance declarations are rejected here
511 ; traceTc "Tc3" empty
512 ; (tcg_env, inst_infos, _deriv_binds)
513 <- tcInstDecls1 (concat tycl_decls) inst_decls deriv_decls
515 ; setGblEnv tcg_env $ do {
517 -- Typecheck value declarations
518 ; traceTc "Tc5" empty
519 ; val_ids <- tcHsBootSigs val_binds
522 -- No simplification or zonking to do
523 ; traceTc "Tc7a" empty
524 ; gbl_env <- getGblEnv
526 -- Make the final type-env
527 -- Include the dfun_ids so that their type sigs
528 -- are written into the interface file.
529 -- And similarly the aux_ids from aux_binds
530 ; let { type_env0 = tcg_type_env gbl_env
531 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
532 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
533 ; type_env3 = extendTypeEnvWithIds type_env2 aux_ids
534 ; dfun_ids = map iDFunId inst_infos
535 ; aux_ids = case aux_binds of
536 ValBindsOut _ sigs -> [id | L _ (IdSig id) <- sigs]
537 _ -> panic "tcRnHsBoodDecls"
540 ; setGlobalTypeEnv gbl_env type_env3
542 ; traceTc "boot" (ppr lie); return gbl_env }
544 badBootDecl :: String -> Located decl -> TcM ()
545 badBootDecl what (L loc _)
546 = addErrAt loc (char 'A' <+> text what
547 <+> ptext (sLit "declaration is not (currently) allowed in a hs-boot file"))
550 Once we've typechecked the body of the module, we want to compare what
551 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
554 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM TcGblEnv
555 -- Compare the hi-boot file for this module (if there is one)
556 -- with the type environment we've just come up with
557 -- In the common case where there is no hi-boot file, the list
558 -- of boot_names is empty.
560 -- The bindings we return give bindings for the dfuns defined in the
561 -- hs-boot file, such as $fbEqT = $fEqT
564 tcg_env@(TcGblEnv { tcg_src = hs_src, tcg_binds = binds,
565 tcg_insts = local_insts,
566 tcg_type_env = local_type_env, tcg_exports = local_exports })
567 (ModDetails { md_insts = boot_insts, md_fam_insts = boot_fam_insts,
568 md_types = boot_type_env, md_exports = boot_exports })
569 | isHsBoot hs_src -- Current module is already a hs-boot file!
573 = do { traceTc "checkHiBootIface" $ vcat
574 [ ppr boot_type_env, ppr boot_insts, ppr boot_exports]
576 -- Check the exports of the boot module, one by one
577 ; mapM_ check_export boot_exports
579 -- Check for no family instances
580 ; unless (null boot_fam_insts) $
581 panic ("TcRnDriver.checkHiBootIface: Cannot handle family " ++
582 "instances in boot files yet...")
583 -- FIXME: Why? The actual comparison is not hard, but what would
584 -- be the equivalent to the dfun bindings returned for class
585 -- instances? We can't easily equate tycons...
587 -- Check instance declarations
588 ; mb_dfun_prs <- mapM check_inst boot_insts
589 ; let dfun_prs = catMaybes mb_dfun_prs
590 boot_dfuns = map fst dfun_prs
591 dfun_binds = listToBag [ mkVarBind boot_dfun (nlHsVar dfun)
592 | (boot_dfun, dfun) <- dfun_prs ]
593 type_env' = extendTypeEnvWithIds local_type_env boot_dfuns
594 tcg_env' = tcg_env { tcg_binds = binds `unionBags` dfun_binds }
597 ; setGlobalTypeEnv tcg_env' type_env' }
598 -- Update the global type env *including* the knot-tied one
599 -- so that if the source module reads in an interface unfolding
600 -- mentioning one of the dfuns from the boot module, then it
601 -- can "see" that boot dfun. See Trac #4003
603 check_export boot_avail -- boot_avail is exported by the boot iface
604 | name `elem` dfun_names = return ()
605 | isWiredInName name = return () -- No checking for wired-in names. In particular,
606 -- 'error' is handled by a rather gross hack
607 -- (see comments in GHC.Err.hs-boot)
609 -- Check that the actual module exports the same thing
610 | not (null missing_names)
611 = addErrAt (nameSrcSpan (head missing_names))
612 (missingBootThing (head missing_names) "exported by")
614 -- If the boot module does not *define* the thing, we are done
615 -- (it simply re-exports it, and names match, so nothing further to do)
616 | isNothing mb_boot_thing = return ()
618 -- Check that the actual module also defines the thing, and
619 -- then compare the definitions
620 | Just real_thing <- lookupTypeEnv local_type_env name,
621 Just boot_thing <- mb_boot_thing
622 = when (not (checkBootDecl boot_thing real_thing))
623 $ addErrAt (nameSrcSpan (getName boot_thing))
624 (let boot_decl = tyThingToIfaceDecl
625 (fromJust mb_boot_thing)
626 real_decl = tyThingToIfaceDecl real_thing
627 in bootMisMatch real_thing boot_decl real_decl)
630 = addErrTc (missingBootThing name "defined in")
632 name = availName boot_avail
633 mb_boot_thing = lookupTypeEnv boot_type_env name
634 missing_names = case lookupNameEnv local_export_env name of
636 Just avail -> availNames boot_avail `minusList` availNames avail
638 dfun_names = map getName boot_insts
640 local_export_env :: NameEnv AvailInfo
641 local_export_env = availsToNameEnv local_exports
643 check_inst :: Instance -> TcM (Maybe (Id, Id))
644 -- Returns a pair of the boot dfun in terms of the equivalent real dfun
646 = case [dfun | inst <- local_insts,
647 let dfun = instanceDFunId inst,
648 idType dfun `eqType` boot_inst_ty ] of
649 [] -> do { traceTc "check_inst" (vcat [ text "local_insts" <+> vcat (map (ppr . idType . instanceDFunId) local_insts)
650 , text "boot_inst" <+> ppr boot_inst
651 , text "boot_inst_ty" <+> ppr boot_inst_ty
653 ; addErrTc (instMisMatch boot_inst); return Nothing }
654 (dfun:_) -> return (Just (local_boot_dfun, dfun))
656 boot_dfun = instanceDFunId boot_inst
657 boot_inst_ty = idType boot_dfun
658 local_boot_dfun = Id.mkExportedLocalId (idName boot_dfun) boot_inst_ty
661 -- This has to compare the TyThing from the .hi-boot file to the TyThing
662 -- in the current source file. We must be careful to allow alpha-renaming
663 -- where appropriate, and also the boot declaration is allowed to omit
664 -- constructors and class methods.
666 -- See rnfail055 for a good test of this stuff.
668 checkBootDecl :: TyThing -> TyThing -> Bool
670 checkBootDecl (AnId id1) (AnId id2)
672 (idType id1 `eqType` idType id2)
674 checkBootDecl (ATyCon tc1) (ATyCon tc2)
675 = checkBootTyCon tc1 tc2
677 checkBootDecl (AClass c1) (AClass c2)
679 (clas_tyvars1, clas_fds1, sc_theta1, _, ats1, op_stuff1)
680 = classExtraBigSig c1
681 (clas_tyvars2, clas_fds2, sc_theta2, _, ats2, op_stuff2)
682 = classExtraBigSig c2
684 env0 = mkRnEnv2 emptyInScopeSet
685 env = rnBndrs2 env0 clas_tyvars1 clas_tyvars2
687 eqSig (id1, def_meth1) (id2, def_meth2)
688 = idName id1 == idName id2 &&
689 eqTypeX env op_ty1 op_ty2 &&
690 def_meth1 == def_meth2
692 (_, rho_ty1) = splitForAllTys (idType id1)
693 op_ty1 = funResultTy rho_ty1
694 (_, rho_ty2) = splitForAllTys (idType id2)
695 op_ty2 = funResultTy rho_ty2
697 eqFD (as1,bs1) (as2,bs2) =
698 eqListBy (eqTypeX env) (mkTyVarTys as1) (mkTyVarTys as2) &&
699 eqListBy (eqTypeX env) (mkTyVarTys bs1) (mkTyVarTys bs2)
701 same_kind tv1 tv2 = eqKind (tyVarKind tv1) (tyVarKind tv2)
703 eqListBy same_kind clas_tyvars1 clas_tyvars2 &&
704 -- Checks kind of class
705 eqListBy eqFD clas_fds1 clas_fds2 &&
706 (null sc_theta1 && null op_stuff1 && null ats1
707 || -- Above tests for an "abstract" class
708 eqListBy (eqPredX env) sc_theta1 sc_theta2 &&
709 eqListBy eqSig op_stuff1 op_stuff2 &&
710 eqListBy checkBootTyCon ats1 ats2)
712 checkBootDecl (ADataCon dc1) (ADataCon _)
713 = pprPanic "checkBootDecl" (ppr dc1)
715 checkBootDecl _ _ = False -- probably shouldn't happen
718 checkBootTyCon :: TyCon -> TyCon -> Bool
719 checkBootTyCon tc1 tc2
720 | not (eqKind (tyConKind tc1) (tyConKind tc2))
721 = False -- First off, check the kind
723 | isSynTyCon tc1 && isSynTyCon tc2
725 let tvs1 = tyConTyVars tc1; tvs2 = tyConTyVars tc2
726 env = rnBndrs2 env0 tvs1 tvs2
728 eqSynRhs SynFamilyTyCon SynFamilyTyCon
730 eqSynRhs (SynonymTyCon t1) (SynonymTyCon t2)
734 equalLength tvs1 tvs2 &&
735 eqSynRhs (synTyConRhs tc1) (synTyConRhs tc2)
737 | isAlgTyCon tc1 && isAlgTyCon tc2
739 eqKind (tyConKind tc1) (tyConKind tc2) &&
740 eqListBy eqPred (tyConStupidTheta tc1) (tyConStupidTheta tc2) &&
741 eqAlgRhs (algTyConRhs tc1) (algTyConRhs tc2)
743 | isForeignTyCon tc1 && isForeignTyCon tc2
744 = eqKind (tyConKind tc1) (tyConKind tc2) &&
745 tyConExtName tc1 == tyConExtName tc2
749 env0 = mkRnEnv2 emptyInScopeSet
751 eqAlgRhs AbstractTyCon _ = True
752 eqAlgRhs DataFamilyTyCon{} DataFamilyTyCon{} = True
753 eqAlgRhs tc1@DataTyCon{} tc2@DataTyCon{} =
754 eqListBy eqCon (data_cons tc1) (data_cons tc2)
755 eqAlgRhs tc1@NewTyCon{} tc2@NewTyCon{} =
756 eqCon (data_con tc1) (data_con tc2)
760 = dataConName c1 == dataConName c2
761 && dataConIsInfix c1 == dataConIsInfix c2
762 && dataConStrictMarks c1 == dataConStrictMarks c2
763 && dataConFieldLabels c1 == dataConFieldLabels c2
764 && eqType (dataConUserType c1) (dataConUserType c2)
767 missingBootThing :: Name -> String -> SDoc
768 missingBootThing name what
769 = ppr name <+> ptext (sLit "is exported by the hs-boot file, but not")
770 <+> text what <+> ptext (sLit "the module")
772 bootMisMatch :: TyThing -> IfaceDecl -> IfaceDecl -> SDoc
773 bootMisMatch thing boot_decl real_decl
774 = vcat [ppr thing <+> ptext (sLit "has conflicting definitions in the module and its hs-boot file"),
775 ptext (sLit "Main module:") <+> ppr real_decl,
776 ptext (sLit "Boot file: ") <+> ppr boot_decl]
778 instMisMatch :: Instance -> SDoc
781 2 (ptext (sLit "is defined in the hs-boot file, but not in the module itself"))
785 %************************************************************************
787 Type-checking the top level of a module
789 %************************************************************************
791 tcRnGroup takes a bunch of top-level source-code declarations, and
793 * gets supporting declarations from interface files
796 * and augments the TcGblEnv with the results
798 In Template Haskell it may be called repeatedly for each group of
799 declarations. It expects there to be an incoming TcGblEnv in the
800 monad; it augments it and returns the new TcGblEnv.
803 ------------------------------------------------
804 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
805 -- Fails if there are any errors
807 = do { -- Rename the source decls
808 traceTc "rn12" empty ;
809 (tcg_env, rn_decls) <- checkNoErrs $ rnSrcDecls group ;
810 traceTc "rn13" empty ;
812 -- save the renamed syntax, if we want it
814 | Just grp <- tcg_rn_decls tcg_env
815 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
819 -- Dump trace of renaming part
820 rnDump (ppr rn_decls) ;
822 return (tcg_env', rn_decls)
825 ------------------------------------------------
826 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
827 tcTopSrcDecls boot_details
828 (HsGroup { hs_tyclds = tycl_decls,
829 hs_instds = inst_decls,
830 hs_derivds = deriv_decls,
831 hs_fords = foreign_decls,
832 hs_defds = default_decls,
833 hs_annds = annotation_decls,
834 hs_ruleds = rule_decls,
835 hs_vects = vect_decls,
836 hs_valds = val_binds })
837 = do { -- Type-check the type and class decls, and all imported decls
838 -- The latter come in via tycl_decls
839 traceTc "Tc2" empty ;
841 (tcg_env, aux_binds, dm_ids) <- tcTyAndClassDecls boot_details tycl_decls ;
842 -- If there are any errors, tcTyAndClassDecls fails here
845 tcExtendIdEnv dm_ids $ do {
847 -- Source-language instances, including derivings,
848 -- and import the supporting declarations
849 traceTc "Tc3" empty ;
850 (tcg_env, inst_infos, deriv_binds)
851 <- tcInstDecls1 (concat tycl_decls) inst_decls deriv_decls;
852 setGblEnv tcg_env $ do {
854 -- Foreign import declarations next.
855 traceTc "Tc4" empty ;
856 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
857 tcExtendGlobalValEnv fi_ids $ do {
859 -- Default declarations
860 traceTc "Tc4a" empty ;
861 default_tys <- tcDefaults default_decls ;
862 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
864 -- Now GHC-generated derived bindings, generics, and selectors
865 -- Do not generate warnings from compiler-generated code;
866 -- hence the use of discardWarnings
867 (tc_aux_binds, specs1, tcl_env) <- discardWarnings (tcTopBinds aux_binds) ;
868 (tc_deriv_binds, specs2, tcl_env) <- setLclTypeEnv tcl_env $
869 discardWarnings (tcTopBinds deriv_binds) ;
871 -- Value declarations next
872 traceTc "Tc5" empty ;
873 (tc_val_binds, specs3, tcl_env) <- setLclTypeEnv tcl_env $
874 tcTopBinds val_binds;
876 setLclTypeEnv tcl_env $ do { -- Environment doesn't change now
878 -- Second pass over class and instance declarations,
879 traceTc "Tc6" empty ;
880 inst_binds <- tcInstDecls2 (concat tycl_decls) inst_infos ;
883 traceTc "Tc7" empty ;
884 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
887 annotations <- tcAnnotations annotation_decls ;
890 rules <- tcRules rule_decls ;
892 -- Vectorisation declarations
893 vects <- tcVectDecls vect_decls ;
896 traceTc "Tc7a" empty ;
897 tcg_env <- getGblEnv ;
898 let { all_binds = tc_val_binds `unionBags`
899 tc_deriv_binds `unionBags`
900 tc_aux_binds `unionBags`
901 inst_binds `unionBags`
904 ; sig_names = mkNameSet (collectHsValBinders val_binds)
905 `minusNameSet` getTypeSigNames val_binds
907 -- Extend the GblEnv with the (as yet un-zonked)
908 -- bindings, rules, foreign decls
909 ; tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds
910 , tcg_imp_specs = tcg_imp_specs tcg_env ++ specs1 ++ specs2 ++
912 , tcg_sigs = tcg_sigs tcg_env `unionNameSets` sig_names
913 , tcg_rules = tcg_rules tcg_env ++ rules
914 , tcg_vects = tcg_vects tcg_env ++ vects
915 , tcg_anns = tcg_anns tcg_env ++ annotations
916 , tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
917 return (tcg_env', tcl_env)
922 %************************************************************************
926 %************************************************************************
929 checkMain :: TcM TcGblEnv
930 -- If we are in module Main, check that 'main' is defined.
932 = do { tcg_env <- getGblEnv ;
934 check_main dflags tcg_env
937 check_main :: DynFlags -> TcGblEnv -> TcM TcGblEnv
938 check_main dflags tcg_env
940 = traceTc "checkMain not" (ppr main_mod <+> ppr mod) >>
944 = do { mb_main <- lookupGlobalOccRn_maybe main_fn
945 -- Check that 'main' is in scope
946 -- It might be imported from another module!
948 Nothing -> do { traceTc "checkMain fail" (ppr main_mod <+> ppr main_fn)
953 { traceTc "checkMain found" (ppr main_mod <+> ppr main_fn)
954 ; let loc = srcLocSpan (getSrcLoc main_name)
955 ; ioTyCon <- tcLookupTyCon ioTyConName
956 ; res_ty <- newFlexiTyVarTy liftedTypeKind
958 <- addErrCtxt mainCtxt $
959 tcMonoExpr (L loc (HsVar main_name)) (mkTyConApp ioTyCon [res_ty])
961 -- See Note [Root-main Id]
962 -- Construct the binding
963 -- :Main.main :: IO res_ty = runMainIO res_ty main
964 ; run_main_id <- tcLookupId runMainIOName
965 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
966 (mkVarOccFS (fsLit "main"))
967 (getSrcSpan main_name)
968 ; root_main_id = Id.mkExportedLocalId root_main_name
969 (mkTyConApp ioTyCon [res_ty])
970 ; co = mkWpTyApps [res_ty]
971 ; rhs = nlHsApp (mkLHsWrap co (nlHsVar run_main_id)) main_expr
972 ; main_bind = mkVarBind root_main_id rhs }
974 ; return (tcg_env { tcg_main = Just main_name,
975 tcg_binds = tcg_binds tcg_env
977 tcg_dus = tcg_dus tcg_env
978 `plusDU` usesOnly (unitFV main_name)
979 -- Record the use of 'main', so that we don't
980 -- complain about it being defined but not used
984 mod = tcg_mod tcg_env
985 main_mod = mainModIs dflags
986 main_fn = getMainFun dflags
988 complain_no_main | ghcLink dflags == LinkInMemory = return ()
989 | otherwise = failWithTc noMainMsg
990 -- In interactive mode, don't worry about the absence of 'main'
991 -- In other modes, fail altogether, so that we don't go on
992 -- and complain a second time when processing the export list.
994 mainCtxt = ptext (sLit "When checking the type of the") <+> pp_main_fn
995 noMainMsg = ptext (sLit "The") <+> pp_main_fn
996 <+> ptext (sLit "is not defined in module") <+> quotes (ppr main_mod)
997 pp_main_fn = ppMainFn main_fn
999 ppMainFn :: RdrName -> SDoc
1001 | main_fn == main_RDR_Unqual
1002 = ptext (sLit "function") <+> quotes (ppr main_fn)
1004 = ptext (sLit "main function") <+> quotes (ppr main_fn)
1006 -- | Get the unqualified name of the function to use as the \"main\" for the main module.
1007 -- Either returns the default name or the one configured on the command line with -main-is
1008 getMainFun :: DynFlags -> RdrName
1009 getMainFun dflags = case (mainFunIs dflags) of
1010 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn))
1011 Nothing -> main_RDR_Unqual
1013 checkMainExported :: TcGblEnv -> TcM ()
1014 checkMainExported tcg_env = do
1016 case tcg_main tcg_env of
1017 Nothing -> return () -- not the main module
1018 Just main_name -> do
1019 let main_mod = mainModIs dflags
1020 checkTc (main_name `elem` concatMap availNames (tcg_exports tcg_env)) $
1021 ptext (sLit "The") <+> ppMainFn (nameRdrName main_name) <+>
1022 ptext (sLit "is not exported by module") <+> quotes (ppr main_mod)
1027 The function that the RTS invokes is always :Main.main, which we call
1028 root_main_id. (Because GHC allows the user to have a module not
1029 called Main as the main module, we can't rely on the main function
1030 being called "Main.main". That's why root_main_id has a fixed module
1033 This is unusual: it's a LocalId whose Name has a Module from another
1034 module. Tiresomely, we must filter it out again in MkIface, les we
1035 get two defns for 'main' in the interface file!
1038 %*********************************************************
1042 %*********************************************************
1045 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
1046 setInteractiveContext hsc_env icxt thing_inside
1047 = let -- Initialise the tcg_inst_env with instances from all home modules.
1048 -- This mimics the more selective call to hptInstances in tcRnModule.
1049 (home_insts, home_fam_insts) = hptInstances hsc_env (\_ -> True)
1051 updGblEnv (\env -> env {
1052 tcg_rdr_env = ic_rn_gbl_env icxt,
1053 tcg_inst_env = extendInstEnvList (tcg_inst_env env) home_insts,
1054 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env env)
1058 tcExtendGhciEnv (ic_tmp_ids icxt) $
1059 -- tcExtendGhciEnv does lots:
1060 -- - it extends the local type env (tcl_env) with the given Ids,
1061 -- - it extends the local rdr env (tcl_rdr) with the Names from
1063 -- - it adds the free tyvars of the Ids to the tcl_tyvars
1066 -- later ids in ic_tmp_ids must shadow earlier ones with the same
1067 -- OccName, and tcExtendIdEnv implements this behaviour.
1069 do { traceTc "setIC" (ppr (ic_tmp_ids icxt))
1077 -> InteractiveContext
1079 -> IO (Messages, Maybe ([Id], LHsExpr Id))
1080 -- The returned [Id] is the list of new Ids bound by
1081 -- this statement. It can be used to extend the
1082 -- InteractiveContext via extendInteractiveContext.
1084 -- The returned TypecheckedHsExpr is of type IO [ () ],
1085 -- a list of the bound values, coerced to ().
1087 tcRnStmt hsc_env ictxt rdr_stmt
1088 = initTcPrintErrors hsc_env iNTERACTIVE $
1089 setInteractiveContext hsc_env ictxt $ do {
1091 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
1092 (([rn_stmt], _), fvs) <- rnStmts GhciStmt [rdr_stmt] $ \_ ->
1093 return ((), emptyFVs) ;
1094 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
1096 rnDump (ppr rn_stmt) ;
1098 -- The real work is done here
1099 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
1100 zonked_expr <- zonkTopLExpr tc_expr ;
1101 zonked_ids <- zonkTopBndrs bound_ids ;
1103 -- None of the Ids should be of unboxed type, because we
1104 -- cast them all to HValues in the end!
1105 mapM_ bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
1107 traceTc "tcs 1" empty ;
1108 let { global_ids = map globaliseAndTidyId zonked_ids } ;
1109 -- Note [Interactively-bound Ids in GHCi]
1111 {- ---------------------------------------------
1112 At one stage I removed any shadowed bindings from the type_env;
1113 they are inaccessible but might, I suppose, cause a space leak if we leave them there.
1114 However, with Template Haskell they aren't necessarily inaccessible. Consider this
1116 Prelude> let f n = n * 2 :: Int
1117 Prelude> fName <- runQ [| f |]
1118 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1120 Prelude> let f n = n * 3 :: Int
1121 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1122 In the last line we use 'fName', which resolves to the *first* 'f'
1123 in scope. If we delete it from the type env, GHCi crashes because
1124 it doesn't expect that.
1126 Hence this code is commented out
1128 -------------------------------------------------- -}
1130 dumpOptTcRn Opt_D_dump_tc
1131 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
1132 text "Typechecked expr" <+> ppr zonked_expr]) ;
1134 return (global_ids, zonked_expr)
1137 bad_unboxed id = addErr (sep [ptext (sLit "GHCi can't bind a variable of unlifted type:"),
1138 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
1141 Note [Interactively-bound Ids in GHCi]
1142 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1143 The Ids bound by previous Stmts in Template Haskell are currently
1145 b) with an Internal Name (not External)
1146 c) and a tidied type
1148 (a) They must be GlobalIds (not LocalIds) otherwise when we come to
1149 compile an expression using these ids later, the byte code
1150 generator will consider the occurrences to be free rather than
1153 (b) They retain their Internal names becuase we don't have a suitable
1154 Module to name them with. We could revisit this choice.
1156 (c) Their types are tidied. This is important, because :info may ask
1157 to look at them, and :info expects the things it looks up to have
1161 --------------------------------------------------------------------------
1162 Typechecking Stmts in GHCi
1164 Here is the grand plan, implemented in tcUserStmt
1166 What you type The IO [HValue] that hscStmt returns
1167 ------------- ------------------------------------
1168 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
1171 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
1174 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
1175 [NB: result not printed] bindings: [it]
1177 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
1178 result showable) bindings: [it]
1180 expr (of non-IO type,
1181 result not showable) ==> error
1185 ---------------------------
1186 type PlanResult = ([Id], LHsExpr Id)
1187 type Plan = TcM PlanResult
1189 runPlans :: [Plan] -> TcM PlanResult
1190 -- Try the plans in order. If one fails (by raising an exn), try the next.
1191 -- If one succeeds, take it.
1192 runPlans [] = panic "runPlans"
1194 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
1196 --------------------
1197 mkPlan :: LStmt Name -> TcM PlanResult
1198 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
1199 = do { uniq <- newUnique -- is treated very specially
1200 ; let fresh_it = itName uniq
1201 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
1202 matches = [mkMatch [] expr emptyLocalBinds]
1203 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
1204 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
1205 (HsVar bindIOName) noSyntaxExpr
1206 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
1207 (HsVar thenIOName) placeHolderType
1210 -- [it <- e; print it] but not if it::()
1212 -- [let it = e; print it]
1213 ; runPlans [ -- Plan A
1214 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
1215 ; it_ty <- zonkTcType (idType it_id)
1216 ; when (isUnitTy it_ty) failM
1219 -- Plan B; a naked bind statment
1220 tcGhciStmts [bind_stmt],
1222 -- Plan C; check that the let-binding is typeable all by itself.
1223 -- If not, fail; if so, try to print it.
1224 -- The two-step process avoids getting two errors: one from
1225 -- the expression itself, and one from the 'print it' part
1226 -- This two-step story is very clunky, alas
1227 do { _ <- checkNoErrs (tcGhciStmts [let_stmt])
1228 --- checkNoErrs defeats the error recovery of let-bindings
1229 ; tcGhciStmts [let_stmt, print_it] }
1232 mkPlan stmt@(L loc (BindStmt {}))
1233 | [v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
1234 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
1235 (HsVar thenIOName) placeHolderType
1237 ; print_bind_result <- doptM Opt_PrintBindResult
1238 ; let print_plan = do
1239 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
1240 ; v_ty <- zonkTcType (idType v_id)
1241 ; when (isUnitTy v_ty || not (isTauTy v_ty)) failM
1245 -- [stmt; print v] but not if v::()
1247 ; runPlans ((if print_bind_result then [print_plan] else []) ++
1248 [tcGhciStmts [stmt]])
1252 = tcGhciStmts [stmt]
1254 ---------------------------
1255 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1257 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1258 ret_id <- tcLookupId returnIOName ; -- return @ IO
1260 ret_ty = mkListTy unitTy ;
1261 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1262 tc_io_stmts stmts = tcStmts GhciStmt tcDoStmt stmts io_ret_ty ;
1264 names = collectLStmtsBinders stmts ;
1266 -- mk_return builds the expression
1267 -- returnIO @ [()] [coerce () x, .., coerce () z]
1269 -- Despite the inconvenience of building the type applications etc,
1270 -- this *has* to be done in type-annotated post-typecheck form
1271 -- because we are going to return a list of *polymorphic* values
1272 -- coerced to type (). If we built a *source* stmt
1273 -- return [coerce x, ..., coerce z]
1274 -- then the type checker would instantiate x..z, and we wouldn't
1275 -- get their *polymorphic* values. (And we'd get ambiguity errs
1276 -- if they were overloaded, since they aren't applied to anything.)
1277 mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty])
1278 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1279 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1283 -- OK, we're ready to typecheck the stmts
1284 traceTc "TcRnDriver.tcGhciStmts: tc stmts" empty ;
1285 ((tc_stmts, ids), lie) <- captureConstraints $ tc_io_stmts stmts $ \ _ ->
1286 mapM tcLookupId names ;
1287 -- Look up the names right in the middle,
1288 -- where they will all be in scope
1290 -- Simplify the context
1291 traceTc "TcRnDriver.tcGhciStmts: simplify ctxt" empty ;
1292 const_binds <- checkNoErrs (simplifyInteractive lie) ;
1293 -- checkNoErrs ensures that the plan fails if context redn fails
1295 traceTc "TcRnDriver.tcGhciStmts: done" empty ;
1296 return (ids, mkHsDictLet (EvBinds const_binds) $
1297 noLoc (HsDo GhciStmt tc_stmts (mk_return ids) io_ret_ty))
1302 tcRnExpr just finds the type of an expression
1306 -> InteractiveContext
1308 -> IO (Messages, Maybe Type)
1309 tcRnExpr hsc_env ictxt rdr_expr
1310 = initTcPrintErrors hsc_env iNTERACTIVE $
1311 setInteractiveContext hsc_env ictxt $ do {
1313 (rn_expr, _fvs) <- rnLExpr rdr_expr ;
1316 -- Now typecheck the expression;
1317 -- it might have a rank-2 type (e.g. :t runST)
1319 let { fresh_it = itName uniq } ;
1320 ((_tc_expr, res_ty), lie) <- captureConstraints (tcInferRho rn_expr) ;
1321 ((qtvs, dicts, _), lie_top) <- captureConstraints $
1322 simplifyInfer TopLevel False {- No MR for now -}
1323 [(fresh_it, res_ty)]
1325 _ <- simplifyInteractive lie_top ; -- Ignore the dicionary bindings
1327 let { all_expr_ty = mkForAllTys qtvs (mkPiTypes dicts res_ty) } ;
1328 zonkTcType all_expr_ty
1332 tcRnType just finds the kind of a type
1336 -> InteractiveContext
1338 -> IO (Messages, Maybe Kind)
1339 tcRnType hsc_env ictxt rdr_type
1340 = initTcPrintErrors hsc_env iNTERACTIVE $
1341 setInteractiveContext hsc_env ictxt $ do {
1343 rn_type <- rnLHsType doc rdr_type ;
1346 -- Now kind-check the type
1347 (_ty', kind) <- kcLHsType rn_type ;
1351 doc = ptext (sLit "In GHCi input")
1357 %************************************************************************
1359 More GHCi stuff, to do with browsing and getting info
1361 %************************************************************************
1365 -- | ASSUMES that the module is either in the 'HomePackageTable' or is
1366 -- a package module with an interface on disk. If neither of these is
1367 -- true, then the result will be an error indicating the interface
1368 -- could not be found.
1369 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe [AvailInfo])
1370 getModuleExports hsc_env mod
1373 checkMods = ic_toplev_scope ic ++ map fst (ic_exports ic)
1375 initTc hsc_env HsSrcFile False iNTERACTIVE (tcGetModuleExports mod checkMods)
1377 -- Get the export avail info and also load all orphan and family-instance
1378 -- modules. Finally, check that the family instances of all modules in the
1379 -- interactive context are consistent (these modules are in the second
1381 tcGetModuleExports :: Module -> [Module] -> TcM [AvailInfo]
1382 tcGetModuleExports mod directlyImpMods
1383 = do { let doc = ptext (sLit "context for compiling statements")
1384 ; iface <- initIfaceTcRn $ loadSysInterface doc mod
1386 -- Load any orphan-module and family instance-module
1387 -- interfaces, so their instances are visible.
1388 ; loadOrphanModules (dep_orphs (mi_deps iface)) False
1389 ; loadOrphanModules (dep_finsts (mi_deps iface)) True
1391 -- Check that the family instances of all directly loaded
1392 -- modules are consistent.
1393 ; checkFamInstConsistency (dep_finsts (mi_deps iface)) directlyImpMods
1395 ; ifaceExportNames (mi_exports iface)
1398 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Messages, Maybe [Name])
1399 tcRnLookupRdrName hsc_env rdr_name
1400 = initTcPrintErrors hsc_env iNTERACTIVE $
1401 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1402 lookup_rdr_name rdr_name
1404 lookup_rdr_name :: RdrName -> TcM [Name]
1405 lookup_rdr_name rdr_name = do {
1406 -- If the identifier is a constructor (begins with an
1407 -- upper-case letter), then we need to consider both
1408 -- constructor and type class identifiers.
1409 let { rdr_names = dataTcOccs rdr_name } ;
1411 -- results :: [Either Messages Name]
1412 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1414 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1415 -- The successful lookups will be (Just name)
1416 let { (warns_s, good_names) = unzip [ (msgs, name)
1417 | (msgs, Just name) <- results] ;
1418 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1420 -- Fail if nothing good happened, else add warnings
1421 if null good_names then
1422 -- No lookup succeeded, so
1423 -- pick the first error message and report it
1424 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1425 -- while the other is "X is not in scope",
1426 -- we definitely want the former; but we might pick the latter
1427 do { addMessages (head errs_s) ; failM }
1428 else -- Add deprecation warnings
1429 mapM_ addMessages warns_s ;
1435 tcRnLookupName :: HscEnv -> Name -> IO (Messages, Maybe TyThing)
1436 tcRnLookupName hsc_env name
1437 = initTcPrintErrors hsc_env iNTERACTIVE $
1438 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1439 tcRnLookupName' name
1441 -- To look up a name we have to look in the local environment (tcl_lcl)
1442 -- as well as the global environment, which is what tcLookup does.
1443 -- But we also want a TyThing, so we have to convert:
1445 tcRnLookupName' :: Name -> TcRn TyThing
1446 tcRnLookupName' name = do
1447 tcthing <- tcLookup name
1449 AGlobal thing -> return thing
1450 ATcId{tct_id=id} -> return (AnId id)
1451 _ -> panic "tcRnLookupName'"
1453 tcRnGetInfo :: HscEnv
1455 -> IO (Messages, Maybe (TyThing, Fixity, [Instance]))
1457 -- Used to implement :info in GHCi
1459 -- Look up a RdrName and return all the TyThings it might be
1460 -- A capitalised RdrName is given to us in the DataName namespace,
1461 -- but we want to treat it as *both* a data constructor
1462 -- *and* as a type or class constructor;
1463 -- hence the call to dataTcOccs, and we return up to two results
1464 tcRnGetInfo hsc_env name
1465 = initTcPrintErrors hsc_env iNTERACTIVE $
1466 tcRnGetInfo' hsc_env name
1468 tcRnGetInfo' :: HscEnv
1470 -> TcRn (TyThing, Fixity, [Instance])
1471 tcRnGetInfo' hsc_env name
1472 = let ictxt = hsc_IC hsc_env in
1473 setInteractiveContext hsc_env ictxt $ do
1475 -- Load the interface for all unqualified types and classes
1476 -- That way we will find all the instance declarations
1477 -- (Packages have not orphan modules, and we assume that
1478 -- in the home package all relevant modules are loaded.)
1479 loadUnqualIfaces ictxt
1481 thing <- tcRnLookupName' name
1482 fixity <- lookupFixityRn name
1483 ispecs <- lookupInsts thing
1484 return (thing, fixity, ispecs)
1486 lookupInsts :: TyThing -> TcM [Instance]
1487 lookupInsts (AClass cls)
1488 = do { inst_envs <- tcGetInstEnvs
1489 ; return (classInstances inst_envs cls) }
1491 lookupInsts (ATyCon tc)
1492 = do { (pkg_ie, home_ie) <- tcGetInstEnvs
1493 -- Load all instances for all classes that are
1494 -- in the type environment (which are all the ones
1495 -- we've seen in any interface file so far)
1496 ; return [ ispec -- Search all
1497 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1498 , let dfun = instanceDFunId ispec
1501 relevant df = tc_name `elemNameSet` orphNamesOfDFunHead (idType df)
1502 tc_name = tyConName tc
1504 lookupInsts _ = return []
1506 loadUnqualIfaces :: InteractiveContext -> TcM ()
1507 -- Load the home module for everything that is in scope unqualified
1508 -- This is so that we can accurately report the instances for
1510 loadUnqualIfaces ictxt
1512 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1514 unqual_mods = [ nameModule name
1515 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1516 let name = gre_name gre,
1517 not (isInternalName name),
1518 isTcOcc (nameOccName name), -- Types and classes only
1519 unQualOK gre ] -- In scope unqualified
1520 doc = ptext (sLit "Need interface for module whose export(s) are in scope unqualified")
1523 %************************************************************************
1527 %************************************************************************
1530 rnDump :: SDoc -> TcRn ()
1531 -- Dump, with a banner, if -ddump-rn
1532 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1534 tcDump :: TcGblEnv -> TcRn ()
1536 = do { dflags <- getDOpts ;
1538 -- Dump short output if -ddump-types or -ddump-tc
1539 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1540 (dumpTcRn short_dump) ;
1542 -- Dump bindings if -ddump-tc
1543 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1546 short_dump = pprTcGblEnv env
1547 full_dump = pprLHsBinds (tcg_binds env)
1548 -- NB: foreign x-d's have undefined's in their types;
1549 -- hence can't show the tc_fords
1551 tcCoreDump :: ModGuts -> TcM ()
1553 = do { dflags <- getDOpts ;
1554 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1555 (dumpTcRn (pprModGuts mod_guts)) ;
1557 -- Dump bindings if -ddump-tc
1558 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1560 full_dump = pprCoreBindings (mg_binds mod_guts)
1562 -- It's unpleasant having both pprModGuts and pprModDetails here
1563 pprTcGblEnv :: TcGblEnv -> SDoc
1564 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1566 tcg_fam_insts = fam_insts,
1569 tcg_imports = imports })
1570 = vcat [ ppr_types insts type_env
1571 , ppr_tycons fam_insts type_env
1573 , ppr_fam_insts fam_insts
1574 , vcat (map ppr rules)
1575 , vcat (map ppr vects)
1576 , ppr_gen_tycons (typeEnvTyCons type_env)
1577 , ptext (sLit "Dependent modules:") <+>
1578 ppr (sortBy cmp_mp $ eltsUFM (imp_dep_mods imports))
1579 , ptext (sLit "Dependent packages:") <+>
1580 ppr (sortBy stablePackageIdCmp $ imp_dep_pkgs imports)]
1581 where -- The two uses of sortBy are just to reduce unnecessary
1582 -- wobbling in testsuite output
1583 cmp_mp (mod_name1, is_boot1) (mod_name2, is_boot2)
1584 = (mod_name1 `stableModuleNameCmp` mod_name2)
1586 (is_boot1 `compare` is_boot2)
1588 pprModGuts :: ModGuts -> SDoc
1589 pprModGuts (ModGuts { mg_types = type_env,
1591 = vcat [ ppr_types [] type_env,
1594 ppr_types :: [Instance] -> TypeEnv -> SDoc
1595 ppr_types insts type_env
1596 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1598 dfun_ids = map instanceDFunId insts
1599 ids = [id | id <- typeEnvIds type_env, want_sig id]
1600 want_sig id | opt_PprStyle_Debug = True
1601 | otherwise = isLocalId id &&
1602 isExternalName (idName id) &&
1603 not (id `elem` dfun_ids)
1604 -- isLocalId ignores data constructors, records selectors etc.
1605 -- The isExternalName ignores local dictionary and method bindings
1606 -- that the type checker has invented. Top-level user-defined things
1607 -- have External names.
1609 ppr_tycons :: [FamInst] -> TypeEnv -> SDoc
1610 ppr_tycons fam_insts type_env
1611 = vcat [ text "TYPE CONSTRUCTORS"
1612 , nest 2 (ppr_tydecls tycons)
1613 , text "COERCION AXIOMS"
1614 , nest 2 (ppr_axioms (typeEnvCoAxioms type_env)) ]
1616 fi_tycons = map famInstTyCon fam_insts
1617 tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
1618 want_tycon tycon | opt_PprStyle_Debug = True
1619 | otherwise = not (isImplicitTyCon tycon) &&
1620 isExternalName (tyConName tycon) &&
1621 not (tycon `elem` fi_tycons)
1623 ppr_insts :: [Instance] -> SDoc
1624 ppr_insts [] = empty
1625 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1627 ppr_fam_insts :: [FamInst] -> SDoc
1628 ppr_fam_insts [] = empty
1629 ppr_fam_insts fam_insts =
1630 text "FAMILY INSTANCES" $$ nest 2 (pprFamInsts fam_insts)
1632 ppr_sigs :: [Var] -> SDoc
1634 -- Print type signatures; sort by OccName
1635 = vcat (map ppr_sig (sortLe le_sig ids))
1637 le_sig id1 id2 = getOccName id1 <= getOccName id2
1638 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1640 ppr_tydecls :: [TyCon] -> SDoc
1642 -- Print type constructor info; sort by OccName
1643 = vcat (map ppr_tycon (sortLe le_sig tycons))
1645 le_sig tycon1 tycon2 = getOccName tycon1 <= getOccName tycon2
1646 ppr_tycon tycon = ppr (tyThingToIfaceDecl (ATyCon tycon))
1649 ppr_axioms :: [CoAxiom] -> SDoc
1651 = vcat (map ppr_ax axs)
1653 ppr_ax ax = sep [ ptext (sLit "coercion") <+> ppr ax <+> ppr (co_ax_tvs ax)
1654 , nest 2 (dcolon <+> pprEqPred
1655 (Pair (co_ax_lhs ax) (co_ax_rhs ax))) ]
1657 ppr_rules :: [CoreRule] -> SDoc
1658 ppr_rules [] = empty
1659 ppr_rules rs = vcat [ptext (sLit "{-# RULES"),
1660 nest 2 (pprRules rs),
1663 ppr_gen_tycons :: [TyCon] -> SDoc
1664 ppr_gen_tycons [] = empty
1665 ppr_gen_tycons tcs = vcat [ptext (sLit "Tycons with generics:"),
1666 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]