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,
22 import {-# SOURCE #-} TcSplice ( tcSpliceDecls )
39 import TcType ( tidyTopType )
75 import TcType ( orphNamesOfDFunHead )
76 import Inst ( tcGetInstEnvs )
77 import Data.List ( sortBy )
80 import TcType ( isUnitTy, isTauTy )
81 import CoreUtils( mkPiTypes )
89 import TidyPgm ( globaliseAndTidyId )
90 import TysWiredIn ( unitTy, mkListTy )
100 #include "HsVersions.h"
103 %************************************************************************
105 Typecheck and rename a module
107 %************************************************************************
113 -> Bool -- True <=> save renamed syntax
114 -> Located (HsModule RdrName)
115 -> IO (Messages, Maybe TcGblEnv)
117 tcRnModule hsc_env hsc_src save_rn_syntax
118 (L loc (HsModule maybe_mod export_ies
119 import_decls local_decls mod_deprec
121 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
123 let { this_pkg = thisPackage (hsc_dflags hsc_env) ;
124 this_mod = case maybe_mod of
125 Nothing -> mAIN -- 'module M where' is omitted
126 Just (L _ mod) -> mkModule this_pkg mod } ;
129 initTc hsc_env hsc_src save_rn_syntax this_mod $
131 do { -- Deal with imports;
132 tcg_env <- tcRnImports hsc_env this_mod import_decls ;
133 setGblEnv tcg_env $ do {
135 -- Load the hi-boot interface for this module, if any
136 -- We do this now so that the boot_names can be passed
137 -- to tcTyAndClassDecls, because the boot_names are
138 -- automatically considered to be loop breakers
140 -- Do this *after* tcRnImports, so that we know whether
141 -- a module that we import imports us; and hence whether to
142 -- look for a hi-boot file
143 boot_iface <- tcHiBootIface hsc_src this_mod ;
145 -- Rename and type check the declarations
146 traceRn (text "rn1a") ;
147 tcg_env <- if isHsBoot hsc_src then
148 tcRnHsBootDecls local_decls
150 tcRnSrcDecls boot_iface local_decls ;
151 setGblEnv tcg_env $ do {
153 -- Report the use of any deprecated things
154 -- We do this *before* processsing the export list so
155 -- that we don't bleat about re-exporting a deprecated
156 -- thing (especially via 'module Foo' export item)
157 -- That is, only uses in the *body* of the module are complained about
158 traceRn (text "rn3") ;
159 failIfErrsM ; -- finishWarnings crashes sometimes
160 -- as a result of typechecker repairs (e.g. unboundNames)
161 tcg_env <- finishWarnings (hsc_dflags hsc_env) mod_deprec tcg_env ;
163 -- Process the export list
164 traceRn (text "rn4a: before exports");
165 tcg_env <- rnExports (isJust maybe_mod) export_ies tcg_env ;
166 traceRn (text "rn4b: after exportss") ;
168 -- Check that main is exported (must be after rnExports)
169 checkMainExported tcg_env ;
171 -- Compare the hi-boot iface (if any) with the real thing
172 -- Must be done after processing the exports
173 tcg_env <- checkHiBootIface tcg_env boot_iface ;
175 -- The new type env is already available to stuff slurped from
176 -- interface files, via TcEnv.updateGlobalTypeEnv
177 -- It's important that this includes the stuff in checkHiBootIface,
178 -- because the latter might add new bindings for boot_dfuns,
179 -- which may be mentioned in imported unfoldings
181 -- Don't need to rename the Haddock documentation,
182 -- it's not parsed by GHC anymore.
183 tcg_env <- return (tcg_env { tcg_doc_hdr = maybe_doc_hdr }) ;
185 -- Report unused names
186 reportUnusedNames export_ies tcg_env ;
188 -- Dump output and return
195 %************************************************************************
199 %************************************************************************
202 tcRnImports :: HscEnv -> Module -> [LImportDecl RdrName] -> TcM TcGblEnv
203 tcRnImports hsc_env this_mod import_decls
204 = do { (rn_imports, rdr_env, imports,hpc_info) <- rnImports import_decls ;
206 ; let { dep_mods :: ModuleNameEnv (ModuleName, IsBootInterface)
207 ; dep_mods = imp_dep_mods imports
209 -- We want instance declarations from all home-package
210 -- modules below this one, including boot modules, except
211 -- ourselves. The 'except ourselves' is so that we don't
212 -- get the instances from this module's hs-boot file
213 ; want_instances :: ModuleName -> Bool
214 ; want_instances mod = mod `elemUFM` dep_mods
215 && mod /= moduleName this_mod
216 ; (home_insts, home_fam_insts) = hptInstances hsc_env
220 -- Record boot-file info in the EPS, so that it's
221 -- visible to loadHiBootInterface in tcRnSrcDecls,
222 -- and any other incrementally-performed imports
223 ; updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
225 -- Update the gbl env
226 ; updGblEnv ( \ gbl ->
228 tcg_rdr_env = plusOccEnv (tcg_rdr_env gbl) rdr_env,
229 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
230 tcg_rn_imports = rn_imports,
231 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
232 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env gbl)
237 ; traceRn (text "rn1" <+> ppr (imp_dep_mods imports))
238 -- Fail if there are any errors so far
239 -- The error printing (if needed) takes advantage
240 -- of the tcg_env we have now set
241 -- ; traceIf (text "rdr_env: " <+> ppr rdr_env)
244 -- Load any orphan-module and family instance-module
245 -- interfaces, so that their rules and instance decls will be
247 ; loadOrphanModules (imp_orphs imports) False
248 ; loadOrphanModules (imp_finsts imports) True
250 -- Check type-familily consistency
251 ; traceRn (text "rn1: checking family instance consistency")
252 ; let { dir_imp_mods = moduleEnvKeys
255 ; checkFamInstConsistency (imp_finsts imports) dir_imp_mods ;
261 %************************************************************************
263 Type-checking external-core modules
265 %************************************************************************
268 tcRnExtCore :: HscEnv
270 -> IO (Messages, Maybe ModGuts)
271 -- Nothing => some error occurred
273 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
274 -- The decls are IfaceDecls; all names are original names
275 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
277 initTc hsc_env ExtCoreFile False this_mod $ do {
279 let { ldecls = map noLoc decls } ;
281 -- bring the type and class decls into scope
282 -- ToDo: check that this doesn't need to extract the val binds.
283 -- It seems that only the type and class decls need to be in scope below because
284 -- (a) tcTyAndClassDecls doesn't need the val binds, and
285 -- (b) tcExtCoreBindings doesn't need anything
286 -- (in fact, it might not even need to be in the scope of
287 -- this tcg_env at all)
288 avails <- getLocalNonValBinders (mkFakeGroup ldecls) ;
289 tc_envs <- extendGlobalRdrEnvRn avails emptyFsEnv {- no fixity decls -} ;
291 setEnvs tc_envs $ do {
293 (rn_decls, _fvs) <- checkNoErrs $ rnTyClDecls [ldecls] ;
295 -- Dump trace of renaming part
296 rnDump (ppr rn_decls) ;
298 -- Typecheck them all together so that
299 -- any mutually recursive types are done right
300 -- Just discard the auxiliary bindings; they are generated
301 -- only for Haskell source code, and should already be in Core
302 (tcg_env, _aux_binds, _dm_ids) <- tcTyAndClassDecls emptyModDetails rn_decls ;
304 setGblEnv tcg_env $ do {
305 -- Make the new type env available to stuff slurped from interface files
307 -- Now the core bindings
308 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
312 bndrs = bindersOfBinds core_binds ;
313 my_exports = map (Avail . idName) bndrs ;
314 -- ToDo: export the data types also?
317 extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
319 mod_guts = ModGuts { mg_module = this_mod,
321 mg_used_names = emptyNameSet, -- ToDo: compute usage
322 mg_dir_imps = emptyModuleEnv, -- ??
323 mg_deps = noDependencies, -- ??
324 mg_exports = my_exports,
325 mg_types = final_type_env,
326 mg_insts = tcg_insts tcg_env,
327 mg_fam_insts = tcg_fam_insts tcg_env,
328 mg_inst_env = tcg_inst_env tcg_env,
329 mg_fam_inst_env = tcg_fam_inst_env tcg_env,
333 mg_binds = core_binds,
336 mg_rdr_env = emptyGlobalRdrEnv,
337 mg_fix_env = emptyFixityEnv,
338 mg_warns = NoWarnings,
339 mg_foreign = NoStubs,
340 mg_hpc_info = emptyHpcInfo False,
341 mg_modBreaks = emptyModBreaks,
342 mg_vect_info = noVectInfo
345 tcCoreDump mod_guts ;
350 mkFakeGroup :: [LTyClDecl a] -> HsGroup a
351 mkFakeGroup decls -- Rather clumsy; lots of unused fields
352 = emptyRdrGroup { hs_tyclds = [decls] }
356 %************************************************************************
358 Type-checking the top level of a module
360 %************************************************************************
363 tcRnSrcDecls :: ModDetails -> [LHsDecl RdrName] -> TcM TcGblEnv
364 -- Returns the variables free in the decls
365 -- Reason: solely to report unused imports and bindings
366 tcRnSrcDecls boot_iface decls
367 = do { -- Do all the declarations
368 (tc_envs, lie) <- captureConstraints $ tc_rn_src_decls boot_iface decls ;
369 ; traceTc "Tc8" empty ;
373 -- Finish simplifying class constraints
375 -- simplifyTop deals with constant or ambiguous InstIds.
376 -- How could there be ambiguous ones? They can only arise if a
377 -- top-level decl falls under the monomorphism restriction
378 -- and no subsequent decl instantiates its type.
380 -- We do this after checkMain, so that we use the type info
381 -- thaat checkMain adds
383 -- We do it with both global and local env in scope:
384 -- * the global env exposes the instances to simplifyTop
385 -- * the local env exposes the local Ids to simplifyTop,
386 -- so that we get better error messages (monomorphism restriction)
387 new_ev_binds <- simplifyTop lie ;
388 traceTc "Tc9" empty ;
390 failIfErrsM ; -- Don't zonk if there have been errors
391 -- It's a waste of time; and we may get debug warnings
392 -- about strangely-typed TyCons!
394 -- Zonk the final code. This must be done last.
395 -- Even simplifyTop may do some unification.
396 -- This pass also warns about missing type signatures
397 let { (tcg_env, _) = tc_envs
398 ; TcGblEnv { tcg_type_env = type_env,
401 tcg_ev_binds = cur_ev_binds,
402 tcg_imp_specs = imp_specs,
405 tcg_fords = fords } = tcg_env
406 ; all_ev_binds = cur_ev_binds `unionBags` new_ev_binds } ;
408 (bind_ids, ev_binds', binds', fords', imp_specs', rules', vects')
409 <- zonkTopDecls all_ev_binds binds sig_ns rules vects imp_specs fords ;
411 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
412 ; tcg_env' = tcg_env { tcg_binds = binds',
413 tcg_ev_binds = ev_binds',
414 tcg_imp_specs = imp_specs',
417 tcg_fords = fords' } } ;
419 setGlobalTypeEnv tcg_env' final_type_env
422 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
423 -- Loops around dealing with each top level inter-splice group
424 -- in turn, until it's dealt with the entire module
425 tc_rn_src_decls boot_details ds
426 = do { (first_group, group_tail) <- findSplice ds ;
427 -- If ds is [] we get ([], Nothing)
429 -- Deal with decls up to, but not including, the first splice
430 (tcg_env, rn_decls) <- rnTopSrcDecls first_group ;
431 -- rnTopSrcDecls fails if there are any errors
433 (tcg_env, tcl_env) <- setGblEnv tcg_env $
434 tcTopSrcDecls boot_details rn_decls ;
436 -- If there is no splice, we're nearly done
437 setEnvs (tcg_env, tcl_env) $
439 Nothing -> do { tcg_env <- checkMain ; -- Check for `main'
440 return (tcg_env, tcl_env)
444 -- There shouldn't be a splice
445 Just (SpliceDecl {}, _) -> do {
446 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
448 -- If there's a splice, we must carry on
449 Just (SpliceDecl splice_expr _, rest_ds) -> do {
451 -- Rename the splice expression, and get its supporting decls
452 (rn_splice_expr, splice_fvs) <- checkNoErrs (rnLExpr splice_expr) ;
453 -- checkNoErrs: don't typecheck if renaming failed
454 rnDump (ppr rn_splice_expr) ;
456 -- Execute the splice
457 spliced_decls <- tcSpliceDecls rn_splice_expr ;
459 -- Glue them on the front of the remaining decls and loop
460 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
461 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
466 %************************************************************************
468 Compiling hs-boot source files, and
469 comparing the hi-boot interface with the real thing
471 %************************************************************************
474 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
475 tcRnHsBootDecls decls
476 = do { (first_group, group_tail) <- findSplice decls
478 -- Rename the declarations
479 ; (tcg_env, HsGroup {
480 hs_tyclds = tycl_decls,
481 hs_instds = inst_decls,
482 hs_derivds = deriv_decls,
483 hs_fords = for_decls,
484 hs_defds = def_decls,
485 hs_ruleds = rule_decls,
486 hs_vects = vect_decls,
488 hs_valds = val_binds }) <- rnTopSrcDecls first_group
489 ; (gbl_env, lie) <- captureConstraints $ setGblEnv tcg_env $ do {
492 -- Check for illegal declarations
494 Just (SpliceDecl d _, _) -> badBootDecl "splice" d
496 ; mapM_ (badBootDecl "foreign") for_decls
497 ; mapM_ (badBootDecl "default") def_decls
498 ; mapM_ (badBootDecl "rule") rule_decls
499 ; mapM_ (badBootDecl "vect") vect_decls
501 -- Typecheck type/class decls
502 ; traceTc "Tc2" empty
503 ; (tcg_env, aux_binds, dm_ids)
504 <- tcTyAndClassDecls emptyModDetails tycl_decls
505 ; setGblEnv tcg_env $
506 tcExtendIdEnv dm_ids $ do {
508 -- Typecheck instance decls
509 -- Family instance declarations are rejected here
510 ; traceTc "Tc3" empty
511 ; (tcg_env, inst_infos, _deriv_binds)
512 <- tcInstDecls1 (concat tycl_decls) inst_decls deriv_decls
514 ; setGblEnv tcg_env $ do {
516 -- Typecheck value declarations
517 ; traceTc "Tc5" empty
518 ; val_ids <- tcHsBootSigs val_binds
521 -- No simplification or zonking to do
522 ; traceTc "Tc7a" empty
523 ; gbl_env <- getGblEnv
525 -- Make the final type-env
526 -- Include the dfun_ids so that their type sigs
527 -- are written into the interface file.
528 -- And similarly the aux_ids from aux_binds
529 ; let { type_env0 = tcg_type_env gbl_env
530 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
531 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
532 ; type_env3 = extendTypeEnvWithIds type_env2 aux_ids
533 ; dfun_ids = map iDFunId inst_infos
534 ; aux_ids = case aux_binds of
535 ValBindsOut _ sigs -> [id | L _ (IdSig id) <- sigs]
536 _ -> panic "tcRnHsBoodDecls"
539 ; setGlobalTypeEnv gbl_env type_env3
541 ; traceTc "boot" (ppr lie); return gbl_env }
543 badBootDecl :: String -> Located decl -> TcM ()
544 badBootDecl what (L loc _)
545 = addErrAt loc (char 'A' <+> text what
546 <+> ptext (sLit "declaration is not (currently) allowed in a hs-boot file"))
549 Once we've typechecked the body of the module, we want to compare what
550 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
553 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM TcGblEnv
554 -- Compare the hi-boot file for this module (if there is one)
555 -- with the type environment we've just come up with
556 -- In the common case where there is no hi-boot file, the list
557 -- of boot_names is empty.
559 -- The bindings we return give bindings for the dfuns defined in the
560 -- hs-boot file, such as $fbEqT = $fEqT
563 tcg_env@(TcGblEnv { tcg_src = hs_src, tcg_binds = binds,
564 tcg_insts = local_insts,
565 tcg_type_env = local_type_env, tcg_exports = local_exports })
566 (ModDetails { md_insts = boot_insts, md_fam_insts = boot_fam_insts,
567 md_types = boot_type_env, md_exports = boot_exports })
568 | isHsBoot hs_src -- Current module is already a hs-boot file!
572 = do { traceTc "checkHiBootIface" $ vcat
573 [ ppr boot_type_env, ppr boot_insts, ppr boot_exports]
575 -- Check the exports of the boot module, one by one
576 ; mapM_ check_export boot_exports
578 -- Check for no family instances
579 ; unless (null boot_fam_insts) $
580 panic ("TcRnDriver.checkHiBootIface: Cannot handle family " ++
581 "instances in boot files yet...")
582 -- FIXME: Why? The actual comparison is not hard, but what would
583 -- be the equivalent to the dfun bindings returned for class
584 -- instances? We can't easily equate tycons...
586 -- Check instance declarations
587 ; mb_dfun_prs <- mapM check_inst boot_insts
588 ; let dfun_prs = catMaybes mb_dfun_prs
589 boot_dfuns = map fst dfun_prs
590 dfun_binds = listToBag [ mkVarBind boot_dfun (nlHsVar dfun)
591 | (boot_dfun, dfun) <- dfun_prs ]
592 type_env' = extendTypeEnvWithIds local_type_env boot_dfuns
593 tcg_env' = tcg_env { tcg_binds = binds `unionBags` dfun_binds }
596 ; setGlobalTypeEnv tcg_env' type_env' }
597 -- Update the global type env *including* the knot-tied one
598 -- so that if the source module reads in an interface unfolding
599 -- mentioning one of the dfuns from the boot module, then it
600 -- can "see" that boot dfun. See Trac #4003
602 check_export boot_avail -- boot_avail is exported by the boot iface
603 | name `elem` dfun_names = return ()
604 | isWiredInName name = return () -- No checking for wired-in names. In particular,
605 -- 'error' is handled by a rather gross hack
606 -- (see comments in GHC.Err.hs-boot)
608 -- Check that the actual module exports the same thing
609 | not (null missing_names)
610 = addErrAt (nameSrcSpan (head missing_names))
611 (missingBootThing (head missing_names) "exported by")
613 -- If the boot module does not *define* the thing, we are done
614 -- (it simply re-exports it, and names match, so nothing further to do)
615 | isNothing mb_boot_thing = return ()
617 -- Check that the actual module also defines the thing, and
618 -- then compare the definitions
619 | Just real_thing <- lookupTypeEnv local_type_env name,
620 Just boot_thing <- mb_boot_thing
621 = when (not (checkBootDecl boot_thing real_thing))
622 $ addErrAt (nameSrcSpan (getName boot_thing))
623 (let boot_decl = tyThingToIfaceDecl
624 (fromJust mb_boot_thing)
625 real_decl = tyThingToIfaceDecl real_thing
626 in bootMisMatch real_thing boot_decl real_decl)
629 = addErrTc (missingBootThing name "defined in")
631 name = availName boot_avail
632 mb_boot_thing = lookupTypeEnv boot_type_env name
633 missing_names = case lookupNameEnv local_export_env name of
635 Just avail -> availNames boot_avail `minusList` availNames avail
637 dfun_names = map getName boot_insts
639 local_export_env :: NameEnv AvailInfo
640 local_export_env = availsToNameEnv local_exports
642 check_inst :: Instance -> TcM (Maybe (Id, Id))
643 -- Returns a pair of the boot dfun in terms of the equivalent real dfun
645 = case [dfun | inst <- local_insts,
646 let dfun = instanceDFunId inst,
647 idType dfun `tcEqType` boot_inst_ty ] of
648 [] -> do { traceTc "check_inst" (vcat [ text "local_insts" <+> vcat (map (ppr . idType . instanceDFunId) local_insts)
649 , text "boot_inst" <+> ppr boot_inst
650 , text "boot_inst_ty" <+> ppr boot_inst_ty
652 ; addErrTc (instMisMatch boot_inst); return Nothing }
653 (dfun:_) -> return (Just (local_boot_dfun, dfun))
655 boot_dfun = instanceDFunId boot_inst
656 boot_inst_ty = idType boot_dfun
657 local_boot_dfun = Id.mkExportedLocalId (idName boot_dfun) boot_inst_ty
660 -- This has to compare the TyThing from the .hi-boot file to the TyThing
661 -- in the current source file. We must be careful to allow alpha-renaming
662 -- where appropriate, and also the boot declaration is allowed to omit
663 -- constructors and class methods.
665 -- See rnfail055 for a good test of this stuff.
667 checkBootDecl :: TyThing -> TyThing -> Bool
669 checkBootDecl (AnId id1) (AnId id2)
671 (idType id1 `tcEqType` idType id2)
673 checkBootDecl (ATyCon tc1) (ATyCon tc2)
674 = checkBootTyCon tc1 tc2
676 checkBootDecl (AClass c1) (AClass c2)
678 (clas_tyvars1, clas_fds1, sc_theta1, _, ats1, op_stuff1)
679 = classExtraBigSig c1
680 (clas_tyvars2, clas_fds2, sc_theta2, _, ats2, op_stuff2)
681 = classExtraBigSig c2
683 env0 = mkRnEnv2 emptyInScopeSet
684 env = rnBndrs2 env0 clas_tyvars1 clas_tyvars2
686 eqSig (id1, def_meth1) (id2, def_meth2)
687 = idName id1 == idName id2 &&
688 tcEqTypeX env op_ty1 op_ty2 &&
689 def_meth1 == def_meth2
691 (_, rho_ty1) = splitForAllTys (idType id1)
692 op_ty1 = funResultTy rho_ty1
693 (_, rho_ty2) = splitForAllTys (idType id2)
694 op_ty2 = funResultTy rho_ty2
696 eqFD (as1,bs1) (as2,bs2) =
697 eqListBy (tcEqTypeX env) (mkTyVarTys as1) (mkTyVarTys as2) &&
698 eqListBy (tcEqTypeX env) (mkTyVarTys bs1) (mkTyVarTys bs2)
700 same_kind tv1 tv2 = eqKind (tyVarKind tv1) (tyVarKind tv2)
702 eqListBy same_kind clas_tyvars1 clas_tyvars2 &&
703 -- Checks kind of class
704 eqListBy eqFD clas_fds1 clas_fds2 &&
705 (null sc_theta1 && null op_stuff1 && null ats1
706 || -- Above tests for an "abstract" class
707 eqListBy (tcEqPredX env) sc_theta1 sc_theta2 &&
708 eqListBy eqSig op_stuff1 op_stuff2 &&
709 eqListBy checkBootTyCon ats1 ats2)
711 checkBootDecl (ADataCon dc1) (ADataCon _)
712 = pprPanic "checkBootDecl" (ppr dc1)
714 checkBootDecl _ _ = False -- probably shouldn't happen
717 checkBootTyCon :: TyCon -> TyCon -> Bool
718 checkBootTyCon tc1 tc2
719 | not (eqKind (tyConKind tc1) (tyConKind tc2))
720 = False -- First off, check the kind
722 | isSynTyCon tc1 && isSynTyCon tc2
724 let tvs1 = tyConTyVars tc1; tvs2 = tyConTyVars tc2
725 env = rnBndrs2 env0 tvs1 tvs2
727 eqSynRhs SynFamilyTyCon SynFamilyTyCon
729 eqSynRhs (SynonymTyCon t1) (SynonymTyCon t2)
730 = tcEqTypeX env t1 t2
733 equalLength tvs1 tvs2 &&
734 eqSynRhs (synTyConRhs tc1) (synTyConRhs tc2)
736 | isAlgTyCon tc1 && isAlgTyCon tc2
738 eqKind (tyConKind tc1) (tyConKind tc2) &&
739 eqListBy tcEqPred (tyConStupidTheta tc1) (tyConStupidTheta tc2) &&
740 eqAlgRhs (algTyConRhs tc1) (algTyConRhs tc2)
742 | isForeignTyCon tc1 && isForeignTyCon tc2
743 = eqKind (tyConKind tc1) (tyConKind tc2) &&
744 tyConExtName tc1 == tyConExtName tc2
748 env0 = mkRnEnv2 emptyInScopeSet
750 eqAlgRhs AbstractTyCon _ = True
751 eqAlgRhs DataFamilyTyCon{} DataFamilyTyCon{} = True
752 eqAlgRhs tc1@DataTyCon{} tc2@DataTyCon{} =
753 eqListBy eqCon (data_cons tc1) (data_cons tc2)
754 eqAlgRhs tc1@NewTyCon{} tc2@NewTyCon{} =
755 eqCon (data_con tc1) (data_con tc2)
759 = dataConName c1 == dataConName c2
760 && dataConIsInfix c1 == dataConIsInfix c2
761 && dataConStrictMarks c1 == dataConStrictMarks c2
762 && dataConFieldLabels c1 == dataConFieldLabels c2
763 && let tvs1 = dataConUnivTyVars c1 ++ dataConExTyVars c1
764 tvs2 = dataConUnivTyVars c2 ++ dataConExTyVars c2
765 env = rnBndrs2 env0 tvs1 tvs2
767 equalLength tvs1 tvs2 &&
768 eqListBy (tcEqPredX env)
769 (dataConEqTheta c1 ++ dataConDictTheta c1)
770 (dataConEqTheta c2 ++ dataConDictTheta c2) &&
771 eqListBy (tcEqTypeX env)
772 (dataConOrigArgTys c1)
773 (dataConOrigArgTys c2)
776 missingBootThing :: Name -> String -> SDoc
777 missingBootThing name what
778 = ppr name <+> ptext (sLit "is exported by the hs-boot file, but not")
779 <+> text what <+> ptext (sLit "the module")
781 bootMisMatch :: TyThing -> IfaceDecl -> IfaceDecl -> SDoc
782 bootMisMatch thing boot_decl real_decl
783 = vcat [ppr thing <+> ptext (sLit "has conflicting definitions in the module and its hs-boot file"),
784 ptext (sLit "Main module:") <+> ppr real_decl,
785 ptext (sLit "Boot file: ") <+> ppr boot_decl]
787 instMisMatch :: Instance -> SDoc
790 2 (ptext (sLit "is defined in the hs-boot file, but not in the module itself"))
794 %************************************************************************
796 Type-checking the top level of a module
798 %************************************************************************
800 tcRnGroup takes a bunch of top-level source-code declarations, and
802 * gets supporting declarations from interface files
805 * and augments the TcGblEnv with the results
807 In Template Haskell it may be called repeatedly for each group of
808 declarations. It expects there to be an incoming TcGblEnv in the
809 monad; it augments it and returns the new TcGblEnv.
812 ------------------------------------------------
813 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
814 -- Fails if there are any errors
816 = do { -- Rename the source decls
817 traceTc "rn12" empty ;
818 (tcg_env, rn_decls) <- checkNoErrs $ rnSrcDecls group ;
819 traceTc "rn13" empty ;
821 -- save the renamed syntax, if we want it
823 | Just grp <- tcg_rn_decls tcg_env
824 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
828 -- Dump trace of renaming part
829 rnDump (ppr rn_decls) ;
831 return (tcg_env', rn_decls)
834 ------------------------------------------------
835 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
836 tcTopSrcDecls boot_details
837 (HsGroup { hs_tyclds = tycl_decls,
838 hs_instds = inst_decls,
839 hs_derivds = deriv_decls,
840 hs_fords = foreign_decls,
841 hs_defds = default_decls,
842 hs_annds = annotation_decls,
843 hs_ruleds = rule_decls,
844 hs_vects = vect_decls,
845 hs_valds = val_binds })
846 = do { -- Type-check the type and class decls, and all imported decls
847 -- The latter come in via tycl_decls
848 traceTc "Tc2" empty ;
850 (tcg_env, aux_binds, dm_ids) <- tcTyAndClassDecls boot_details tycl_decls ;
851 -- If there are any errors, tcTyAndClassDecls fails here
854 tcExtendIdEnv dm_ids $ do {
856 -- Source-language instances, including derivings,
857 -- and import the supporting declarations
858 traceTc "Tc3" empty ;
859 (tcg_env, inst_infos, deriv_binds)
860 <- tcInstDecls1 (concat tycl_decls) inst_decls deriv_decls;
861 setGblEnv tcg_env $ do {
863 -- Foreign import declarations next.
864 traceTc "Tc4" empty ;
865 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
866 tcExtendGlobalValEnv fi_ids $ do {
868 -- Default declarations
869 traceTc "Tc4a" empty ;
870 default_tys <- tcDefaults default_decls ;
871 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
873 -- Now GHC-generated derived bindings, generics, and selectors
874 -- Do not generate warnings from compiler-generated code;
875 -- hence the use of discardWarnings
876 (tc_aux_binds, specs1, tcl_env) <- discardWarnings (tcTopBinds aux_binds) ;
877 (tc_deriv_binds, specs2, tcl_env) <- setLclTypeEnv tcl_env $
878 discardWarnings (tcTopBinds deriv_binds) ;
880 -- Value declarations next
881 traceTc "Tc5" empty ;
882 (tc_val_binds, specs3, tcl_env) <- setLclTypeEnv tcl_env $
883 tcTopBinds val_binds;
885 setLclTypeEnv tcl_env $ do { -- Environment doesn't change now
887 -- Second pass over class and instance declarations,
888 traceTc "Tc6" empty ;
889 inst_binds <- tcInstDecls2 (concat tycl_decls) inst_infos ;
892 traceTc "Tc7" empty ;
893 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
896 annotations <- tcAnnotations annotation_decls ;
899 rules <- tcRules rule_decls ;
901 -- Vectorisation declarations
902 vects <- tcVectDecls vect_decls ;
905 traceTc "Tc7a" empty ;
906 tcg_env <- getGblEnv ;
907 let { all_binds = tc_val_binds `unionBags`
908 tc_deriv_binds `unionBags`
909 tc_aux_binds `unionBags`
910 inst_binds `unionBags`
913 ; sig_names = mkNameSet (collectHsValBinders val_binds)
914 `minusNameSet` getTypeSigNames val_binds
916 -- Extend the GblEnv with the (as yet un-zonked)
917 -- bindings, rules, foreign decls
918 ; tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds
919 , tcg_imp_specs = tcg_imp_specs tcg_env ++ specs1 ++ specs2 ++
921 , tcg_sigs = tcg_sigs tcg_env `unionNameSets` sig_names
922 , tcg_rules = tcg_rules tcg_env ++ rules
923 , tcg_vects = tcg_vects tcg_env ++ vects
924 , tcg_anns = tcg_anns tcg_env ++ annotations
925 , tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
926 return (tcg_env', tcl_env)
931 %************************************************************************
935 %************************************************************************
938 checkMain :: TcM TcGblEnv
939 -- If we are in module Main, check that 'main' is defined.
941 = do { tcg_env <- getGblEnv ;
943 check_main dflags tcg_env
946 check_main :: DynFlags -> TcGblEnv -> TcM TcGblEnv
947 check_main dflags tcg_env
949 = traceTc "checkMain not" (ppr main_mod <+> ppr mod) >>
953 = do { mb_main <- lookupGlobalOccRn_maybe main_fn
954 -- Check that 'main' is in scope
955 -- It might be imported from another module!
957 Nothing -> do { traceTc "checkMain fail" (ppr main_mod <+> ppr main_fn)
962 { traceTc "checkMain found" (ppr main_mod <+> ppr main_fn)
963 ; let loc = srcLocSpan (getSrcLoc main_name)
964 ; ioTyCon <- tcLookupTyCon ioTyConName
965 ; res_ty <- newFlexiTyVarTy liftedTypeKind
967 <- addErrCtxt mainCtxt $
968 tcMonoExpr (L loc (HsVar main_name)) (mkTyConApp ioTyCon [res_ty])
970 -- See Note [Root-main Id]
971 -- Construct the binding
972 -- :Main.main :: IO res_ty = runMainIO res_ty main
973 ; run_main_id <- tcLookupId runMainIOName
974 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
975 (mkVarOccFS (fsLit "main"))
976 (getSrcSpan main_name)
977 ; root_main_id = Id.mkExportedLocalId root_main_name
978 (mkTyConApp ioTyCon [res_ty])
979 ; co = mkWpTyApps [res_ty]
980 ; rhs = nlHsApp (mkLHsWrap co (nlHsVar run_main_id)) main_expr
981 ; main_bind = mkVarBind root_main_id rhs }
983 ; return (tcg_env { tcg_main = Just main_name,
984 tcg_binds = tcg_binds tcg_env
986 tcg_dus = tcg_dus tcg_env
987 `plusDU` usesOnly (unitFV main_name)
988 -- Record the use of 'main', so that we don't
989 -- complain about it being defined but not used
993 mod = tcg_mod tcg_env
994 main_mod = mainModIs dflags
995 main_fn = getMainFun dflags
997 complain_no_main | ghcLink dflags == LinkInMemory = return ()
998 | otherwise = failWithTc noMainMsg
999 -- In interactive mode, don't worry about the absence of 'main'
1000 -- In other modes, fail altogether, so that we don't go on
1001 -- and complain a second time when processing the export list.
1003 mainCtxt = ptext (sLit "When checking the type of the") <+> pp_main_fn
1004 noMainMsg = ptext (sLit "The") <+> pp_main_fn
1005 <+> ptext (sLit "is not defined in module") <+> quotes (ppr main_mod)
1006 pp_main_fn = ppMainFn main_fn
1008 ppMainFn :: RdrName -> SDoc
1010 | main_fn == main_RDR_Unqual
1011 = ptext (sLit "function") <+> quotes (ppr main_fn)
1013 = ptext (sLit "main function") <+> quotes (ppr main_fn)
1015 -- | Get the unqualified name of the function to use as the \"main\" for the main module.
1016 -- Either returns the default name or the one configured on the command line with -main-is
1017 getMainFun :: DynFlags -> RdrName
1018 getMainFun dflags = case (mainFunIs dflags) of
1019 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn))
1020 Nothing -> main_RDR_Unqual
1022 checkMainExported :: TcGblEnv -> TcM ()
1023 checkMainExported tcg_env = do
1025 case tcg_main tcg_env of
1026 Nothing -> return () -- not the main module
1027 Just main_name -> do
1028 let main_mod = mainModIs dflags
1029 checkTc (main_name `elem` concatMap availNames (tcg_exports tcg_env)) $
1030 ptext (sLit "The") <+> ppMainFn (nameRdrName main_name) <+>
1031 ptext (sLit "is not exported by module") <+> quotes (ppr main_mod)
1036 The function that the RTS invokes is always :Main.main, which we call
1037 root_main_id. (Because GHC allows the user to have a module not
1038 called Main as the main module, we can't rely on the main function
1039 being called "Main.main". That's why root_main_id has a fixed module
1042 This is unusual: it's a LocalId whose Name has a Module from another
1043 module. Tiresomely, we must filter it out again in MkIface, les we
1044 get two defns for 'main' in the interface file!
1047 %*********************************************************
1051 %*********************************************************
1054 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
1055 setInteractiveContext hsc_env icxt thing_inside
1056 = let -- Initialise the tcg_inst_env with instances from all home modules.
1057 -- This mimics the more selective call to hptInstances in tcRnModule.
1058 (home_insts, home_fam_insts) = hptInstances hsc_env (\_ -> True)
1060 updGblEnv (\env -> env {
1061 tcg_rdr_env = ic_rn_gbl_env icxt,
1062 tcg_inst_env = extendInstEnvList (tcg_inst_env env) home_insts,
1063 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env env)
1067 tcExtendGhciEnv (ic_tmp_ids icxt) $
1068 -- tcExtendGhciEnv does lots:
1069 -- - it extends the local type env (tcl_env) with the given Ids,
1070 -- - it extends the local rdr env (tcl_rdr) with the Names from
1072 -- - it adds the free tyvars of the Ids to the tcl_tyvars
1075 -- later ids in ic_tmp_ids must shadow earlier ones with the same
1076 -- OccName, and tcExtendIdEnv implements this behaviour.
1078 do { traceTc "setIC" (ppr (ic_tmp_ids icxt))
1086 -> InteractiveContext
1088 -> IO (Messages, Maybe ([Id], LHsExpr Id))
1089 -- The returned [Id] is the list of new Ids bound by
1090 -- this statement. It can be used to extend the
1091 -- InteractiveContext via extendInteractiveContext.
1093 -- The returned TypecheckedHsExpr is of type IO [ () ],
1094 -- a list of the bound values, coerced to ().
1096 tcRnStmt hsc_env ictxt rdr_stmt
1097 = initTcPrintErrors hsc_env iNTERACTIVE $
1098 setInteractiveContext hsc_env ictxt $ do {
1100 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
1101 (([rn_stmt], _), fvs) <- rnStmts GhciStmt [rdr_stmt] $ \_ ->
1102 return ((), emptyFVs) ;
1103 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
1105 rnDump (ppr rn_stmt) ;
1107 -- The real work is done here
1108 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
1109 zonked_expr <- zonkTopLExpr tc_expr ;
1110 zonked_ids <- zonkTopBndrs bound_ids ;
1112 -- None of the Ids should be of unboxed type, because we
1113 -- cast them all to HValues in the end!
1114 mapM_ bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
1116 traceTc "tcs 1" empty ;
1117 let { global_ids = map globaliseAndTidyId zonked_ids } ;
1118 -- Note [Interactively-bound Ids in GHCi]
1120 {- ---------------------------------------------
1121 At one stage I removed any shadowed bindings from the type_env;
1122 they are inaccessible but might, I suppose, cause a space leak if we leave them there.
1123 However, with Template Haskell they aren't necessarily inaccessible. Consider this
1125 Prelude> let f n = n * 2 :: Int
1126 Prelude> fName <- runQ [| f |]
1127 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1129 Prelude> let f n = n * 3 :: Int
1130 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1131 In the last line we use 'fName', which resolves to the *first* 'f'
1132 in scope. If we delete it from the type env, GHCi crashes because
1133 it doesn't expect that.
1135 Hence this code is commented out
1137 -------------------------------------------------- -}
1139 dumpOptTcRn Opt_D_dump_tc
1140 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
1141 text "Typechecked expr" <+> ppr zonked_expr]) ;
1143 return (global_ids, zonked_expr)
1146 bad_unboxed id = addErr (sep [ptext (sLit "GHCi can't bind a variable of unlifted type:"),
1147 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
1150 Note [Interactively-bound Ids in GHCi]
1151 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1152 The Ids bound by previous Stmts in Template Haskell are currently
1154 b) with an Internal Name (not External)
1155 c) and a tidied type
1157 (a) They must be GlobalIds (not LocalIds) otherwise when we come to
1158 compile an expression using these ids later, the byte code
1159 generator will consider the occurrences to be free rather than
1162 (b) They retain their Internal names becuase we don't have a suitable
1163 Module to name them with. We could revisit this choice.
1165 (c) Their types are tidied. This is important, because :info may ask
1166 to look at them, and :info expects the things it looks up to have
1170 --------------------------------------------------------------------------
1171 Typechecking Stmts in GHCi
1173 Here is the grand plan, implemented in tcUserStmt
1175 What you type The IO [HValue] that hscStmt returns
1176 ------------- ------------------------------------
1177 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
1180 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
1183 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
1184 [NB: result not printed] bindings: [it]
1186 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
1187 result showable) bindings: [it]
1189 expr (of non-IO type,
1190 result not showable) ==> error
1194 ---------------------------
1195 type PlanResult = ([Id], LHsExpr Id)
1196 type Plan = TcM PlanResult
1198 runPlans :: [Plan] -> TcM PlanResult
1199 -- Try the plans in order. If one fails (by raising an exn), try the next.
1200 -- If one succeeds, take it.
1201 runPlans [] = panic "runPlans"
1203 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
1205 --------------------
1206 mkPlan :: LStmt Name -> TcM PlanResult
1207 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
1208 = do { uniq <- newUnique -- is treated very specially
1209 ; let fresh_it = itName uniq
1210 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
1211 matches = [mkMatch [] expr emptyLocalBinds]
1212 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
1213 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
1214 (HsVar bindIOName) noSyntaxExpr
1215 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
1216 (HsVar thenIOName) placeHolderType
1219 -- [it <- e; print it] but not if it::()
1221 -- [let it = e; print it]
1222 ; runPlans [ -- Plan A
1223 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
1224 ; it_ty <- zonkTcType (idType it_id)
1225 ; when (isUnitTy it_ty) failM
1228 -- Plan B; a naked bind statment
1229 tcGhciStmts [bind_stmt],
1231 -- Plan C; check that the let-binding is typeable all by itself.
1232 -- If not, fail; if so, try to print it.
1233 -- The two-step process avoids getting two errors: one from
1234 -- the expression itself, and one from the 'print it' part
1235 -- This two-step story is very clunky, alas
1236 do { _ <- checkNoErrs (tcGhciStmts [let_stmt])
1237 --- checkNoErrs defeats the error recovery of let-bindings
1238 ; tcGhciStmts [let_stmt, print_it] }
1241 mkPlan stmt@(L loc (BindStmt {}))
1242 | [v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
1243 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
1244 (HsVar thenIOName) placeHolderType
1246 ; print_bind_result <- doptM Opt_PrintBindResult
1247 ; let print_plan = do
1248 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
1249 ; v_ty <- zonkTcType (idType v_id)
1250 ; when (isUnitTy v_ty || not (isTauTy v_ty)) failM
1254 -- [stmt; print v] but not if v::()
1256 ; runPlans ((if print_bind_result then [print_plan] else []) ++
1257 [tcGhciStmts [stmt]])
1261 = tcGhciStmts [stmt]
1263 ---------------------------
1264 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1266 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1267 ret_id <- tcLookupId returnIOName ; -- return @ IO
1269 ret_ty = mkListTy unitTy ;
1270 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1271 tc_io_stmts stmts = tcStmts GhciStmt tcDoStmt stmts io_ret_ty ;
1273 names = collectLStmtsBinders stmts ;
1275 -- mk_return builds the expression
1276 -- returnIO @ [()] [coerce () x, .., coerce () z]
1278 -- Despite the inconvenience of building the type applications etc,
1279 -- this *has* to be done in type-annotated post-typecheck form
1280 -- because we are going to return a list of *polymorphic* values
1281 -- coerced to type (). If we built a *source* stmt
1282 -- return [coerce x, ..., coerce z]
1283 -- then the type checker would instantiate x..z, and we wouldn't
1284 -- get their *polymorphic* values. (And we'd get ambiguity errs
1285 -- if they were overloaded, since they aren't applied to anything.)
1286 mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty])
1287 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1288 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1292 -- OK, we're ready to typecheck the stmts
1293 traceTc "TcRnDriver.tcGhciStmts: tc stmts" empty ;
1294 ((tc_stmts, ids), lie) <- captureConstraints $ tc_io_stmts stmts $ \ _ ->
1295 mapM tcLookupId names ;
1296 -- Look up the names right in the middle,
1297 -- where they will all be in scope
1299 -- Simplify the context
1300 traceTc "TcRnDriver.tcGhciStmts: simplify ctxt" empty ;
1301 const_binds <- checkNoErrs (simplifyInteractive lie) ;
1302 -- checkNoErrs ensures that the plan fails if context redn fails
1304 traceTc "TcRnDriver.tcGhciStmts: done" empty ;
1305 return (ids, mkHsDictLet (EvBinds const_binds) $
1306 noLoc (HsDo GhciStmt tc_stmts (mk_return ids) io_ret_ty))
1311 tcRnExpr just finds the type of an expression
1315 -> InteractiveContext
1317 -> IO (Messages, Maybe Type)
1318 tcRnExpr hsc_env ictxt rdr_expr
1319 = initTcPrintErrors hsc_env iNTERACTIVE $
1320 setInteractiveContext hsc_env ictxt $ do {
1322 (rn_expr, _fvs) <- rnLExpr rdr_expr ;
1325 -- Now typecheck the expression;
1326 -- it might have a rank-2 type (e.g. :t runST)
1329 let { fresh_it = itName uniq } ;
1330 ((_tc_expr, res_ty), lie) <- captureConstraints (tcInferRho rn_expr) ;
1331 ((qtvs, dicts, _), lie_top) <- captureConstraints $
1332 simplifyInfer TopLevel
1333 False {- No MR for now -}
1334 [(fresh_it, res_ty)]
1337 _ <- simplifyInteractive lie_top ; -- Ignore the dicionary bindings
1339 let { all_expr_ty = mkForAllTys qtvs (mkPiTypes dicts res_ty) } ;
1340 zonkTcType all_expr_ty
1344 tcRnType just finds the kind of a type
1348 -> InteractiveContext
1350 -> IO (Messages, Maybe Kind)
1351 tcRnType hsc_env ictxt rdr_type
1352 = initTcPrintErrors hsc_env iNTERACTIVE $
1353 setInteractiveContext hsc_env ictxt $ do {
1355 rn_type <- rnLHsType doc rdr_type ;
1358 -- Now kind-check the type
1359 (_ty', kind) <- kcLHsType rn_type ;
1363 doc = ptext (sLit "In GHCi input")
1369 %************************************************************************
1371 More GHCi stuff, to do with browsing and getting info
1373 %************************************************************************
1377 -- | ASSUMES that the module is either in the 'HomePackageTable' or is
1378 -- a package module with an interface on disk. If neither of these is
1379 -- true, then the result will be an error indicating the interface
1380 -- could not be found.
1381 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe [AvailInfo])
1382 getModuleExports hsc_env mod
1385 checkMods = ic_toplev_scope ic ++ map fst (ic_exports ic)
1387 initTc hsc_env HsSrcFile False iNTERACTIVE (tcGetModuleExports mod checkMods)
1389 -- Get the export avail info and also load all orphan and family-instance
1390 -- modules. Finally, check that the family instances of all modules in the
1391 -- interactive context are consistent (these modules are in the second
1393 tcGetModuleExports :: Module -> [Module] -> TcM [AvailInfo]
1394 tcGetModuleExports mod directlyImpMods
1395 = do { let doc = ptext (sLit "context for compiling statements")
1396 ; iface <- initIfaceTcRn $ loadSysInterface doc mod
1398 -- Load any orphan-module and family instance-module
1399 -- interfaces, so their instances are visible.
1400 ; loadOrphanModules (dep_orphs (mi_deps iface)) False
1401 ; loadOrphanModules (dep_finsts (mi_deps iface)) True
1403 -- Check that the family instances of all directly loaded
1404 -- modules are consistent.
1405 ; checkFamInstConsistency (dep_finsts (mi_deps iface)) directlyImpMods
1407 ; ifaceExportNames (mi_exports iface)
1410 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Messages, Maybe [Name])
1411 tcRnLookupRdrName hsc_env rdr_name
1412 = initTcPrintErrors hsc_env iNTERACTIVE $
1413 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1414 lookup_rdr_name rdr_name
1416 lookup_rdr_name :: RdrName -> TcM [Name]
1417 lookup_rdr_name rdr_name = do {
1418 -- If the identifier is a constructor (begins with an
1419 -- upper-case letter), then we need to consider both
1420 -- constructor and type class identifiers.
1421 let { rdr_names = dataTcOccs rdr_name } ;
1423 -- results :: [Either Messages Name]
1424 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1426 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1427 -- The successful lookups will be (Just name)
1428 let { (warns_s, good_names) = unzip [ (msgs, name)
1429 | (msgs, Just name) <- results] ;
1430 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1432 -- Fail if nothing good happened, else add warnings
1433 if null good_names then
1434 -- No lookup succeeded, so
1435 -- pick the first error message and report it
1436 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1437 -- while the other is "X is not in scope",
1438 -- we definitely want the former; but we might pick the latter
1439 do { addMessages (head errs_s) ; failM }
1440 else -- Add deprecation warnings
1441 mapM_ addMessages warns_s ;
1447 tcRnLookupName :: HscEnv -> Name -> IO (Messages, Maybe TyThing)
1448 tcRnLookupName hsc_env name
1449 = initTcPrintErrors hsc_env iNTERACTIVE $
1450 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1451 tcRnLookupName' name
1453 -- To look up a name we have to look in the local environment (tcl_lcl)
1454 -- as well as the global environment, which is what tcLookup does.
1455 -- But we also want a TyThing, so we have to convert:
1457 tcRnLookupName' :: Name -> TcRn TyThing
1458 tcRnLookupName' name = do
1459 tcthing <- tcLookup name
1461 AGlobal thing -> return thing
1462 ATcId{tct_id=id} -> return (AnId id)
1463 _ -> panic "tcRnLookupName'"
1465 tcRnGetInfo :: HscEnv
1467 -> IO (Messages, Maybe (TyThing, Fixity, [Instance]))
1469 -- Used to implement :info in GHCi
1471 -- Look up a RdrName and return all the TyThings it might be
1472 -- A capitalised RdrName is given to us in the DataName namespace,
1473 -- but we want to treat it as *both* a data constructor
1474 -- *and* as a type or class constructor;
1475 -- hence the call to dataTcOccs, and we return up to two results
1476 tcRnGetInfo hsc_env name
1477 = initTcPrintErrors hsc_env iNTERACTIVE $
1478 tcRnGetInfo' hsc_env name
1480 tcRnGetInfo' :: HscEnv
1482 -> TcRn (TyThing, Fixity, [Instance])
1483 tcRnGetInfo' hsc_env name
1484 = let ictxt = hsc_IC hsc_env in
1485 setInteractiveContext hsc_env ictxt $ do
1487 -- Load the interface for all unqualified types and classes
1488 -- That way we will find all the instance declarations
1489 -- (Packages have not orphan modules, and we assume that
1490 -- in the home package all relevant modules are loaded.)
1491 loadUnqualIfaces ictxt
1493 thing <- tcRnLookupName' name
1494 fixity <- lookupFixityRn name
1495 ispecs <- lookupInsts thing
1496 return (thing, fixity, ispecs)
1498 lookupInsts :: TyThing -> TcM [Instance]
1499 lookupInsts (AClass cls)
1500 = do { inst_envs <- tcGetInstEnvs
1501 ; return (classInstances inst_envs cls) }
1503 lookupInsts (ATyCon tc)
1504 = do { (pkg_ie, home_ie) <- tcGetInstEnvs
1505 -- Load all instances for all classes that are
1506 -- in the type environment (which are all the ones
1507 -- we've seen in any interface file so far)
1508 ; return [ ispec -- Search all
1509 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1510 , let dfun = instanceDFunId ispec
1513 relevant df = tc_name `elemNameSet` orphNamesOfDFunHead (idType df)
1514 tc_name = tyConName tc
1516 lookupInsts _ = return []
1518 loadUnqualIfaces :: InteractiveContext -> TcM ()
1519 -- Load the home module for everything that is in scope unqualified
1520 -- This is so that we can accurately report the instances for
1522 loadUnqualIfaces ictxt
1524 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1526 unqual_mods = [ nameModule name
1527 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1528 let name = gre_name gre,
1529 not (isInternalName name),
1530 isTcOcc (nameOccName name), -- Types and classes only
1531 unQualOK gre ] -- In scope unqualified
1532 doc = ptext (sLit "Need interface for module whose export(s) are in scope unqualified")
1535 %************************************************************************
1539 %************************************************************************
1542 rnDump :: SDoc -> TcRn ()
1543 -- Dump, with a banner, if -ddump-rn
1544 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1546 tcDump :: TcGblEnv -> TcRn ()
1548 = do { dflags <- getDOpts ;
1550 -- Dump short output if -ddump-types or -ddump-tc
1551 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1552 (dumpTcRn short_dump) ;
1554 -- Dump bindings if -ddump-tc
1555 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1558 short_dump = pprTcGblEnv env
1559 full_dump = pprLHsBinds (tcg_binds env)
1560 -- NB: foreign x-d's have undefined's in their types;
1561 -- hence can't show the tc_fords
1563 tcCoreDump :: ModGuts -> TcM ()
1565 = do { dflags <- getDOpts ;
1566 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1567 (dumpTcRn (pprModGuts mod_guts)) ;
1569 -- Dump bindings if -ddump-tc
1570 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1572 full_dump = pprCoreBindings (mg_binds mod_guts)
1574 -- It's unpleasant having both pprModGuts and pprModDetails here
1575 pprTcGblEnv :: TcGblEnv -> SDoc
1576 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1578 tcg_fam_insts = fam_insts,
1581 tcg_imports = imports })
1582 = vcat [ ppr_types insts type_env
1583 , ppr_tycons fam_insts type_env
1585 , ppr_fam_insts fam_insts
1586 , vcat (map ppr rules)
1587 , vcat (map ppr vects)
1588 , ppr_gen_tycons (typeEnvTyCons type_env)
1589 , ptext (sLit "Dependent modules:") <+>
1590 ppr (sortBy cmp_mp $ eltsUFM (imp_dep_mods imports))
1591 , ptext (sLit "Dependent packages:") <+>
1592 ppr (sortBy stablePackageIdCmp $ imp_dep_pkgs imports)]
1593 where -- The two uses of sortBy are just to reduce unnecessary
1594 -- wobbling in testsuite output
1595 cmp_mp (mod_name1, is_boot1) (mod_name2, is_boot2)
1596 = (mod_name1 `stableModuleNameCmp` mod_name2)
1598 (is_boot1 `compare` is_boot2)
1600 pprModGuts :: ModGuts -> SDoc
1601 pprModGuts (ModGuts { mg_types = type_env,
1603 = vcat [ ppr_types [] type_env,
1606 ppr_types :: [Instance] -> TypeEnv -> SDoc
1607 ppr_types insts type_env
1608 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1610 dfun_ids = map instanceDFunId insts
1611 ids = [id | id <- typeEnvIds type_env, want_sig id]
1612 want_sig id | opt_PprStyle_Debug = True
1613 | otherwise = isLocalId id &&
1614 isExternalName (idName id) &&
1615 not (id `elem` dfun_ids)
1616 -- isLocalId ignores data constructors, records selectors etc.
1617 -- The isExternalName ignores local dictionary and method bindings
1618 -- that the type checker has invented. Top-level user-defined things
1619 -- have External names.
1621 ppr_tycons :: [FamInst] -> TypeEnv -> SDoc
1622 ppr_tycons fam_insts type_env
1623 = text "TYPE CONSTRUCTORS" $$ nest 4 (ppr_tydecls tycons)
1625 fi_tycons = map famInstTyCon fam_insts
1626 tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
1627 want_tycon tycon | opt_PprStyle_Debug = True
1628 | otherwise = not (isImplicitTyCon tycon) &&
1629 isExternalName (tyConName tycon) &&
1630 not (tycon `elem` fi_tycons)
1632 ppr_insts :: [Instance] -> SDoc
1633 ppr_insts [] = empty
1634 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1636 ppr_fam_insts :: [FamInst] -> SDoc
1637 ppr_fam_insts [] = empty
1638 ppr_fam_insts fam_insts =
1639 text "FAMILY INSTANCES" $$ nest 2 (pprFamInsts fam_insts)
1641 ppr_sigs :: [Var] -> SDoc
1643 -- Print type signatures; sort by OccName
1644 = vcat (map ppr_sig (sortLe le_sig ids))
1646 le_sig id1 id2 = getOccName id1 <= getOccName id2
1647 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1649 ppr_tydecls :: [TyCon] -> SDoc
1651 -- Print type constructor info; sort by OccName
1652 = vcat (map ppr_tycon (sortLe le_sig tycons))
1654 le_sig tycon1 tycon2 = getOccName tycon1 <= getOccName tycon2
1656 | isCoercionTyCon tycon
1657 = sep [ptext (sLit "coercion") <+> ppr tycon <+> ppr tvs
1658 , nest 2 (dcolon <+> pprEqPred (coercionKind (mkTyConApp tycon (mkTyVarTys tvs))))]
1659 | otherwise = ppr (tyThingToIfaceDecl (ATyCon tycon))
1661 tvs = take (tyConArity tycon) alphaTyVars
1663 ppr_rules :: [CoreRule] -> SDoc
1664 ppr_rules [] = empty
1665 ppr_rules rs = vcat [ptext (sLit "{-# RULES"),
1666 nest 2 (pprRules rs),
1669 ppr_gen_tycons :: [TyCon] -> SDoc
1670 ppr_gen_tycons [] = empty
1671 ppr_gen_tycons tcs = vcat [ptext (sLit "Tycons with generics:"),
1672 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]