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 `tcEqType` 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 `tcEqType` 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 tcEqTypeX 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 (tcEqTypeX env) (mkTyVarTys as1) (mkTyVarTys as2) &&
699 eqListBy (tcEqTypeX 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 (tcEqPredX 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)
731 = tcEqTypeX env t1 t2
734 equalLength tvs1 tvs2 &&
735 eqSynRhs (synTyConRhs tc1) (synTyConRhs tc2)
737 | isAlgTyCon tc1 && isAlgTyCon tc2
739 eqKind (tyConKind tc1) (tyConKind tc2) &&
740 eqListBy tcEqPred (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 && let tvs1 = dataConUnivTyVars c1 ++ dataConExTyVars c1
765 tvs2 = dataConUnivTyVars c2 ++ dataConExTyVars c2
766 env = rnBndrs2 env0 tvs1 tvs2
768 equalLength tvs1 tvs2 &&
769 eqListBy (tcEqPredX env)
770 (dataConEqTheta c1 ++ dataConDictTheta c1)
771 (dataConEqTheta c2 ++ dataConDictTheta c2) &&
772 eqListBy (tcEqTypeX env)
773 (dataConOrigArgTys c1)
774 (dataConOrigArgTys c2)
777 missingBootThing :: Name -> String -> SDoc
778 missingBootThing name what
779 = ppr name <+> ptext (sLit "is exported by the hs-boot file, but not")
780 <+> text what <+> ptext (sLit "the module")
782 bootMisMatch :: TyThing -> IfaceDecl -> IfaceDecl -> SDoc
783 bootMisMatch thing boot_decl real_decl
784 = vcat [ppr thing <+> ptext (sLit "has conflicting definitions in the module and its hs-boot file"),
785 ptext (sLit "Main module:") <+> ppr real_decl,
786 ptext (sLit "Boot file: ") <+> ppr boot_decl]
788 instMisMatch :: Instance -> SDoc
791 2 (ptext (sLit "is defined in the hs-boot file, but not in the module itself"))
795 %************************************************************************
797 Type-checking the top level of a module
799 %************************************************************************
801 tcRnGroup takes a bunch of top-level source-code declarations, and
803 * gets supporting declarations from interface files
806 * and augments the TcGblEnv with the results
808 In Template Haskell it may be called repeatedly for each group of
809 declarations. It expects there to be an incoming TcGblEnv in the
810 monad; it augments it and returns the new TcGblEnv.
813 ------------------------------------------------
814 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
815 -- Fails if there are any errors
817 = do { -- Rename the source decls
818 traceTc "rn12" empty ;
819 (tcg_env, rn_decls) <- checkNoErrs $ rnSrcDecls group ;
820 traceTc "rn13" empty ;
822 -- save the renamed syntax, if we want it
824 | Just grp <- tcg_rn_decls tcg_env
825 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
829 -- Dump trace of renaming part
830 rnDump (ppr rn_decls) ;
832 return (tcg_env', rn_decls)
835 ------------------------------------------------
836 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
837 tcTopSrcDecls boot_details
838 (HsGroup { hs_tyclds = tycl_decls,
839 hs_instds = inst_decls,
840 hs_derivds = deriv_decls,
841 hs_fords = foreign_decls,
842 hs_defds = default_decls,
843 hs_annds = annotation_decls,
844 hs_ruleds = rule_decls,
845 hs_vects = vect_decls,
846 hs_valds = val_binds })
847 = do { -- Type-check the type and class decls, and all imported decls
848 -- The latter come in via tycl_decls
849 traceTc "Tc2" empty ;
851 (tcg_env, aux_binds, dm_ids) <- tcTyAndClassDecls boot_details tycl_decls ;
852 -- If there are any errors, tcTyAndClassDecls fails here
855 tcExtendIdEnv dm_ids $ do {
857 -- Source-language instances, including derivings,
858 -- and import the supporting declarations
859 traceTc "Tc3" empty ;
860 (tcg_env, inst_infos, deriv_binds)
861 <- tcInstDecls1 (concat tycl_decls) inst_decls deriv_decls;
862 setGblEnv tcg_env $ do {
864 -- Foreign import declarations next.
865 traceTc "Tc4" empty ;
866 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
867 tcExtendGlobalValEnv fi_ids $ do {
869 -- Default declarations
870 traceTc "Tc4a" empty ;
871 default_tys <- tcDefaults default_decls ;
872 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
874 -- Now GHC-generated derived bindings, generics, and selectors
875 -- Do not generate warnings from compiler-generated code;
876 -- hence the use of discardWarnings
877 (tc_aux_binds, specs1, tcl_env) <- discardWarnings (tcTopBinds aux_binds) ;
878 (tc_deriv_binds, specs2, tcl_env) <- setLclTypeEnv tcl_env $
879 discardWarnings (tcTopBinds deriv_binds) ;
881 -- Value declarations next
882 traceTc "Tc5" empty ;
883 (tc_val_binds, specs3, tcl_env) <- setLclTypeEnv tcl_env $
884 tcTopBinds val_binds;
886 setLclTypeEnv tcl_env $ do { -- Environment doesn't change now
888 -- Second pass over class and instance declarations,
889 traceTc "Tc6" empty ;
890 inst_binds <- tcInstDecls2 (concat tycl_decls) inst_infos ;
893 traceTc "Tc7" empty ;
894 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
897 annotations <- tcAnnotations annotation_decls ;
900 rules <- tcRules rule_decls ;
902 -- Vectorisation declarations
903 vects <- tcVectDecls vect_decls ;
906 traceTc "Tc7a" empty ;
907 tcg_env <- getGblEnv ;
908 let { all_binds = tc_val_binds `unionBags`
909 tc_deriv_binds `unionBags`
910 tc_aux_binds `unionBags`
911 inst_binds `unionBags`
914 ; sig_names = mkNameSet (collectHsValBinders val_binds)
915 `minusNameSet` getTypeSigNames val_binds
917 -- Extend the GblEnv with the (as yet un-zonked)
918 -- bindings, rules, foreign decls
919 ; tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds
920 , tcg_imp_specs = tcg_imp_specs tcg_env ++ specs1 ++ specs2 ++
922 , tcg_sigs = tcg_sigs tcg_env `unionNameSets` sig_names
923 , tcg_rules = tcg_rules tcg_env ++ rules
924 , tcg_vects = tcg_vects tcg_env ++ vects
925 , tcg_anns = tcg_anns tcg_env ++ annotations
926 , tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
927 return (tcg_env', tcl_env)
932 %************************************************************************
936 %************************************************************************
939 checkMain :: TcM TcGblEnv
940 -- If we are in module Main, check that 'main' is defined.
942 = do { tcg_env <- getGblEnv ;
944 check_main dflags tcg_env
947 check_main :: DynFlags -> TcGblEnv -> TcM TcGblEnv
948 check_main dflags tcg_env
950 = traceTc "checkMain not" (ppr main_mod <+> ppr mod) >>
954 = do { mb_main <- lookupGlobalOccRn_maybe main_fn
955 -- Check that 'main' is in scope
956 -- It might be imported from another module!
958 Nothing -> do { traceTc "checkMain fail" (ppr main_mod <+> ppr main_fn)
963 { traceTc "checkMain found" (ppr main_mod <+> ppr main_fn)
964 ; let loc = srcLocSpan (getSrcLoc main_name)
965 ; ioTyCon <- tcLookupTyCon ioTyConName
966 ; res_ty <- newFlexiTyVarTy liftedTypeKind
968 <- addErrCtxt mainCtxt $
969 tcMonoExpr (L loc (HsVar main_name)) (mkTyConApp ioTyCon [res_ty])
971 -- See Note [Root-main Id]
972 -- Construct the binding
973 -- :Main.main :: IO res_ty = runMainIO res_ty main
974 ; run_main_id <- tcLookupId runMainIOName
975 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
976 (mkVarOccFS (fsLit "main"))
977 (getSrcSpan main_name)
978 ; root_main_id = Id.mkExportedLocalId root_main_name
979 (mkTyConApp ioTyCon [res_ty])
980 ; co = mkWpTyApps [res_ty]
981 ; rhs = nlHsApp (mkLHsWrap co (nlHsVar run_main_id)) main_expr
982 ; main_bind = mkVarBind root_main_id rhs }
984 ; return (tcg_env { tcg_main = Just main_name,
985 tcg_binds = tcg_binds tcg_env
987 tcg_dus = tcg_dus tcg_env
988 `plusDU` usesOnly (unitFV main_name)
989 -- Record the use of 'main', so that we don't
990 -- complain about it being defined but not used
994 mod = tcg_mod tcg_env
995 main_mod = mainModIs dflags
996 main_fn = getMainFun dflags
998 complain_no_main | ghcLink dflags == LinkInMemory = return ()
999 | otherwise = failWithTc noMainMsg
1000 -- In interactive mode, don't worry about the absence of 'main'
1001 -- In other modes, fail altogether, so that we don't go on
1002 -- and complain a second time when processing the export list.
1004 mainCtxt = ptext (sLit "When checking the type of the") <+> pp_main_fn
1005 noMainMsg = ptext (sLit "The") <+> pp_main_fn
1006 <+> ptext (sLit "is not defined in module") <+> quotes (ppr main_mod)
1007 pp_main_fn = ppMainFn main_fn
1009 ppMainFn :: RdrName -> SDoc
1011 | main_fn == main_RDR_Unqual
1012 = ptext (sLit "function") <+> quotes (ppr main_fn)
1014 = ptext (sLit "main function") <+> quotes (ppr main_fn)
1016 -- | Get the unqualified name of the function to use as the \"main\" for the main module.
1017 -- Either returns the default name or the one configured on the command line with -main-is
1018 getMainFun :: DynFlags -> RdrName
1019 getMainFun dflags = case (mainFunIs dflags) of
1020 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn))
1021 Nothing -> main_RDR_Unqual
1023 checkMainExported :: TcGblEnv -> TcM ()
1024 checkMainExported tcg_env = do
1026 case tcg_main tcg_env of
1027 Nothing -> return () -- not the main module
1028 Just main_name -> do
1029 let main_mod = mainModIs dflags
1030 checkTc (main_name `elem` concatMap availNames (tcg_exports tcg_env)) $
1031 ptext (sLit "The") <+> ppMainFn (nameRdrName main_name) <+>
1032 ptext (sLit "is not exported by module") <+> quotes (ppr main_mod)
1037 The function that the RTS invokes is always :Main.main, which we call
1038 root_main_id. (Because GHC allows the user to have a module not
1039 called Main as the main module, we can't rely on the main function
1040 being called "Main.main". That's why root_main_id has a fixed module
1043 This is unusual: it's a LocalId whose Name has a Module from another
1044 module. Tiresomely, we must filter it out again in MkIface, les we
1045 get two defns for 'main' in the interface file!
1048 %*********************************************************
1052 %*********************************************************
1055 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
1056 setInteractiveContext hsc_env icxt thing_inside
1057 = let -- Initialise the tcg_inst_env with instances from all home modules.
1058 -- This mimics the more selective call to hptInstances in tcRnModule.
1059 (home_insts, home_fam_insts) = hptInstances hsc_env (\_ -> True)
1061 updGblEnv (\env -> env {
1062 tcg_rdr_env = ic_rn_gbl_env icxt,
1063 tcg_inst_env = extendInstEnvList (tcg_inst_env env) home_insts,
1064 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env env)
1068 tcExtendGhciEnv (ic_tmp_ids icxt) $
1069 -- tcExtendGhciEnv does lots:
1070 -- - it extends the local type env (tcl_env) with the given Ids,
1071 -- - it extends the local rdr env (tcl_rdr) with the Names from
1073 -- - it adds the free tyvars of the Ids to the tcl_tyvars
1076 -- later ids in ic_tmp_ids must shadow earlier ones with the same
1077 -- OccName, and tcExtendIdEnv implements this behaviour.
1079 do { traceTc "setIC" (ppr (ic_tmp_ids icxt))
1087 -> InteractiveContext
1089 -> IO (Messages, Maybe ([Id], LHsExpr Id))
1090 -- The returned [Id] is the list of new Ids bound by
1091 -- this statement. It can be used to extend the
1092 -- InteractiveContext via extendInteractiveContext.
1094 -- The returned TypecheckedHsExpr is of type IO [ () ],
1095 -- a list of the bound values, coerced to ().
1097 tcRnStmt hsc_env ictxt rdr_stmt
1098 = initTcPrintErrors hsc_env iNTERACTIVE $
1099 setInteractiveContext hsc_env ictxt $ do {
1101 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
1102 (([rn_stmt], _), fvs) <- rnStmts GhciStmt [rdr_stmt] $ \_ ->
1103 return ((), emptyFVs) ;
1104 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
1106 rnDump (ppr rn_stmt) ;
1108 -- The real work is done here
1109 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
1110 zonked_expr <- zonkTopLExpr tc_expr ;
1111 zonked_ids <- zonkTopBndrs bound_ids ;
1113 -- None of the Ids should be of unboxed type, because we
1114 -- cast them all to HValues in the end!
1115 mapM_ bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
1117 traceTc "tcs 1" empty ;
1118 let { global_ids = map globaliseAndTidyId zonked_ids } ;
1119 -- Note [Interactively-bound Ids in GHCi]
1121 {- ---------------------------------------------
1122 At one stage I removed any shadowed bindings from the type_env;
1123 they are inaccessible but might, I suppose, cause a space leak if we leave them there.
1124 However, with Template Haskell they aren't necessarily inaccessible. Consider this
1126 Prelude> let f n = n * 2 :: Int
1127 Prelude> fName <- runQ [| f |]
1128 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1130 Prelude> let f n = n * 3 :: Int
1131 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1132 In the last line we use 'fName', which resolves to the *first* 'f'
1133 in scope. If we delete it from the type env, GHCi crashes because
1134 it doesn't expect that.
1136 Hence this code is commented out
1138 -------------------------------------------------- -}
1140 dumpOptTcRn Opt_D_dump_tc
1141 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
1142 text "Typechecked expr" <+> ppr zonked_expr]) ;
1144 return (global_ids, zonked_expr)
1147 bad_unboxed id = addErr (sep [ptext (sLit "GHCi can't bind a variable of unlifted type:"),
1148 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
1151 Note [Interactively-bound Ids in GHCi]
1152 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1153 The Ids bound by previous Stmts in Template Haskell are currently
1155 b) with an Internal Name (not External)
1156 c) and a tidied type
1158 (a) They must be GlobalIds (not LocalIds) otherwise when we come to
1159 compile an expression using these ids later, the byte code
1160 generator will consider the occurrences to be free rather than
1163 (b) They retain their Internal names becuase we don't have a suitable
1164 Module to name them with. We could revisit this choice.
1166 (c) Their types are tidied. This is important, because :info may ask
1167 to look at them, and :info expects the things it looks up to have
1171 --------------------------------------------------------------------------
1172 Typechecking Stmts in GHCi
1174 Here is the grand plan, implemented in tcUserStmt
1176 What you type The IO [HValue] that hscStmt returns
1177 ------------- ------------------------------------
1178 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
1181 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
1184 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
1185 [NB: result not printed] bindings: [it]
1187 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
1188 result showable) bindings: [it]
1190 expr (of non-IO type,
1191 result not showable) ==> error
1195 ---------------------------
1196 type PlanResult = ([Id], LHsExpr Id)
1197 type Plan = TcM PlanResult
1199 runPlans :: [Plan] -> TcM PlanResult
1200 -- Try the plans in order. If one fails (by raising an exn), try the next.
1201 -- If one succeeds, take it.
1202 runPlans [] = panic "runPlans"
1204 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
1206 --------------------
1207 mkPlan :: LStmt Name -> TcM PlanResult
1208 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
1209 = do { uniq <- newUnique -- is treated very specially
1210 ; let fresh_it = itName uniq
1211 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
1212 matches = [mkMatch [] expr emptyLocalBinds]
1213 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
1214 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
1215 (HsVar bindIOName) noSyntaxExpr
1216 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
1217 (HsVar thenIOName) placeHolderType
1220 -- [it <- e; print it] but not if it::()
1222 -- [let it = e; print it]
1223 ; runPlans [ -- Plan A
1224 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
1225 ; it_ty <- zonkTcType (idType it_id)
1226 ; when (isUnitTy it_ty) failM
1229 -- Plan B; a naked bind statment
1230 tcGhciStmts [bind_stmt],
1232 -- Plan C; check that the let-binding is typeable all by itself.
1233 -- If not, fail; if so, try to print it.
1234 -- The two-step process avoids getting two errors: one from
1235 -- the expression itself, and one from the 'print it' part
1236 -- This two-step story is very clunky, alas
1237 do { _ <- checkNoErrs (tcGhciStmts [let_stmt])
1238 --- checkNoErrs defeats the error recovery of let-bindings
1239 ; tcGhciStmts [let_stmt, print_it] }
1242 mkPlan stmt@(L loc (BindStmt {}))
1243 | [v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
1244 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
1245 (HsVar thenIOName) placeHolderType
1247 ; print_bind_result <- doptM Opt_PrintBindResult
1248 ; let print_plan = do
1249 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
1250 ; v_ty <- zonkTcType (idType v_id)
1251 ; when (isUnitTy v_ty || not (isTauTy v_ty)) failM
1255 -- [stmt; print v] but not if v::()
1257 ; runPlans ((if print_bind_result then [print_plan] else []) ++
1258 [tcGhciStmts [stmt]])
1262 = tcGhciStmts [stmt]
1264 ---------------------------
1265 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1267 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1268 ret_id <- tcLookupId returnIOName ; -- return @ IO
1270 ret_ty = mkListTy unitTy ;
1271 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1272 tc_io_stmts stmts = tcStmts GhciStmt tcDoStmt stmts io_ret_ty ;
1274 names = collectLStmtsBinders stmts ;
1276 -- mk_return builds the expression
1277 -- returnIO @ [()] [coerce () x, .., coerce () z]
1279 -- Despite the inconvenience of building the type applications etc,
1280 -- this *has* to be done in type-annotated post-typecheck form
1281 -- because we are going to return a list of *polymorphic* values
1282 -- coerced to type (). If we built a *source* stmt
1283 -- return [coerce x, ..., coerce z]
1284 -- then the type checker would instantiate x..z, and we wouldn't
1285 -- get their *polymorphic* values. (And we'd get ambiguity errs
1286 -- if they were overloaded, since they aren't applied to anything.)
1287 mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty])
1288 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1289 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1293 -- OK, we're ready to typecheck the stmts
1294 traceTc "TcRnDriver.tcGhciStmts: tc stmts" empty ;
1295 ((tc_stmts, ids), lie) <- captureConstraints $ tc_io_stmts stmts $ \ _ ->
1296 mapM tcLookupId names ;
1297 -- Look up the names right in the middle,
1298 -- where they will all be in scope
1300 -- Simplify the context
1301 traceTc "TcRnDriver.tcGhciStmts: simplify ctxt" empty ;
1302 const_binds <- checkNoErrs (simplifyInteractive lie) ;
1303 -- checkNoErrs ensures that the plan fails if context redn fails
1305 traceTc "TcRnDriver.tcGhciStmts: done" empty ;
1306 return (ids, mkHsDictLet (EvBinds const_binds) $
1307 noLoc (HsDo GhciStmt tc_stmts (mk_return ids) io_ret_ty))
1312 tcRnExpr just finds the type of an expression
1316 -> InteractiveContext
1318 -> IO (Messages, Maybe Type)
1319 tcRnExpr hsc_env ictxt rdr_expr
1320 = initTcPrintErrors hsc_env iNTERACTIVE $
1321 setInteractiveContext hsc_env ictxt $ do {
1323 (rn_expr, _fvs) <- rnLExpr rdr_expr ;
1326 -- Now typecheck the expression;
1327 -- it might have a rank-2 type (e.g. :t runST)
1330 let { fresh_it = itName uniq } ;
1331 ((_tc_expr, res_ty), lie) <- captureConstraints (tcInferRho rn_expr) ;
1332 ((qtvs, dicts, _), lie_top) <- captureConstraints $
1333 simplifyInfer TopLevel
1334 False {- No MR for now -}
1335 [(fresh_it, res_ty)]
1338 _ <- simplifyInteractive lie_top ; -- Ignore the dicionary bindings
1340 let { all_expr_ty = mkForAllTys qtvs (mkPiTypes dicts res_ty) } ;
1341 zonkTcType all_expr_ty
1345 tcRnType just finds the kind of a type
1349 -> InteractiveContext
1351 -> IO (Messages, Maybe Kind)
1352 tcRnType hsc_env ictxt rdr_type
1353 = initTcPrintErrors hsc_env iNTERACTIVE $
1354 setInteractiveContext hsc_env ictxt $ do {
1356 rn_type <- rnLHsType doc rdr_type ;
1359 -- Now kind-check the type
1360 (_ty', kind) <- kcLHsType rn_type ;
1364 doc = ptext (sLit "In GHCi input")
1370 %************************************************************************
1372 More GHCi stuff, to do with browsing and getting info
1374 %************************************************************************
1378 -- | ASSUMES that the module is either in the 'HomePackageTable' or is
1379 -- a package module with an interface on disk. If neither of these is
1380 -- true, then the result will be an error indicating the interface
1381 -- could not be found.
1382 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe [AvailInfo])
1383 getModuleExports hsc_env mod
1386 checkMods = ic_toplev_scope ic ++ map fst (ic_exports ic)
1388 initTc hsc_env HsSrcFile False iNTERACTIVE (tcGetModuleExports mod checkMods)
1390 -- Get the export avail info and also load all orphan and family-instance
1391 -- modules. Finally, check that the family instances of all modules in the
1392 -- interactive context are consistent (these modules are in the second
1394 tcGetModuleExports :: Module -> [Module] -> TcM [AvailInfo]
1395 tcGetModuleExports mod directlyImpMods
1396 = do { let doc = ptext (sLit "context for compiling statements")
1397 ; iface <- initIfaceTcRn $ loadSysInterface doc mod
1399 -- Load any orphan-module and family instance-module
1400 -- interfaces, so their instances are visible.
1401 ; loadOrphanModules (dep_orphs (mi_deps iface)) False
1402 ; loadOrphanModules (dep_finsts (mi_deps iface)) True
1404 -- Check that the family instances of all directly loaded
1405 -- modules are consistent.
1406 ; checkFamInstConsistency (dep_finsts (mi_deps iface)) directlyImpMods
1408 ; ifaceExportNames (mi_exports iface)
1411 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Messages, Maybe [Name])
1412 tcRnLookupRdrName hsc_env rdr_name
1413 = initTcPrintErrors hsc_env iNTERACTIVE $
1414 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1415 lookup_rdr_name rdr_name
1417 lookup_rdr_name :: RdrName -> TcM [Name]
1418 lookup_rdr_name rdr_name = do {
1419 -- If the identifier is a constructor (begins with an
1420 -- upper-case letter), then we need to consider both
1421 -- constructor and type class identifiers.
1422 let { rdr_names = dataTcOccs rdr_name } ;
1424 -- results :: [Either Messages Name]
1425 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1427 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1428 -- The successful lookups will be (Just name)
1429 let { (warns_s, good_names) = unzip [ (msgs, name)
1430 | (msgs, Just name) <- results] ;
1431 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1433 -- Fail if nothing good happened, else add warnings
1434 if null good_names then
1435 -- No lookup succeeded, so
1436 -- pick the first error message and report it
1437 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1438 -- while the other is "X is not in scope",
1439 -- we definitely want the former; but we might pick the latter
1440 do { addMessages (head errs_s) ; failM }
1441 else -- Add deprecation warnings
1442 mapM_ addMessages warns_s ;
1448 tcRnLookupName :: HscEnv -> Name -> IO (Messages, Maybe TyThing)
1449 tcRnLookupName hsc_env name
1450 = initTcPrintErrors hsc_env iNTERACTIVE $
1451 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1452 tcRnLookupName' name
1454 -- To look up a name we have to look in the local environment (tcl_lcl)
1455 -- as well as the global environment, which is what tcLookup does.
1456 -- But we also want a TyThing, so we have to convert:
1458 tcRnLookupName' :: Name -> TcRn TyThing
1459 tcRnLookupName' name = do
1460 tcthing <- tcLookup name
1462 AGlobal thing -> return thing
1463 ATcId{tct_id=id} -> return (AnId id)
1464 _ -> panic "tcRnLookupName'"
1466 tcRnGetInfo :: HscEnv
1468 -> IO (Messages, Maybe (TyThing, Fixity, [Instance]))
1470 -- Used to implement :info in GHCi
1472 -- Look up a RdrName and return all the TyThings it might be
1473 -- A capitalised RdrName is given to us in the DataName namespace,
1474 -- but we want to treat it as *both* a data constructor
1475 -- *and* as a type or class constructor;
1476 -- hence the call to dataTcOccs, and we return up to two results
1477 tcRnGetInfo hsc_env name
1478 = initTcPrintErrors hsc_env iNTERACTIVE $
1479 tcRnGetInfo' hsc_env name
1481 tcRnGetInfo' :: HscEnv
1483 -> TcRn (TyThing, Fixity, [Instance])
1484 tcRnGetInfo' hsc_env name
1485 = let ictxt = hsc_IC hsc_env in
1486 setInteractiveContext hsc_env ictxt $ do
1488 -- Load the interface for all unqualified types and classes
1489 -- That way we will find all the instance declarations
1490 -- (Packages have not orphan modules, and we assume that
1491 -- in the home package all relevant modules are loaded.)
1492 loadUnqualIfaces ictxt
1494 thing <- tcRnLookupName' name
1495 fixity <- lookupFixityRn name
1496 ispecs <- lookupInsts thing
1497 return (thing, fixity, ispecs)
1499 lookupInsts :: TyThing -> TcM [Instance]
1500 lookupInsts (AClass cls)
1501 = do { inst_envs <- tcGetInstEnvs
1502 ; return (classInstances inst_envs cls) }
1504 lookupInsts (ATyCon tc)
1505 = do { (pkg_ie, home_ie) <- tcGetInstEnvs
1506 -- Load all instances for all classes that are
1507 -- in the type environment (which are all the ones
1508 -- we've seen in any interface file so far)
1509 ; return [ ispec -- Search all
1510 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1511 , let dfun = instanceDFunId ispec
1514 relevant df = tc_name `elemNameSet` orphNamesOfDFunHead (idType df)
1515 tc_name = tyConName tc
1517 lookupInsts _ = return []
1519 loadUnqualIfaces :: InteractiveContext -> TcM ()
1520 -- Load the home module for everything that is in scope unqualified
1521 -- This is so that we can accurately report the instances for
1523 loadUnqualIfaces ictxt
1525 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1527 unqual_mods = [ nameModule name
1528 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1529 let name = gre_name gre,
1530 not (isInternalName name),
1531 isTcOcc (nameOccName name), -- Types and classes only
1532 unQualOK gre ] -- In scope unqualified
1533 doc = ptext (sLit "Need interface for module whose export(s) are in scope unqualified")
1536 %************************************************************************
1540 %************************************************************************
1543 rnDump :: SDoc -> TcRn ()
1544 -- Dump, with a banner, if -ddump-rn
1545 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1547 tcDump :: TcGblEnv -> TcRn ()
1549 = do { dflags <- getDOpts ;
1551 -- Dump short output if -ddump-types or -ddump-tc
1552 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1553 (dumpTcRn short_dump) ;
1555 -- Dump bindings if -ddump-tc
1556 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1559 short_dump = pprTcGblEnv env
1560 full_dump = pprLHsBinds (tcg_binds env)
1561 -- NB: foreign x-d's have undefined's in their types;
1562 -- hence can't show the tc_fords
1564 tcCoreDump :: ModGuts -> TcM ()
1566 = do { dflags <- getDOpts ;
1567 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1568 (dumpTcRn (pprModGuts mod_guts)) ;
1570 -- Dump bindings if -ddump-tc
1571 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1573 full_dump = pprCoreBindings (mg_binds mod_guts)
1575 -- It's unpleasant having both pprModGuts and pprModDetails here
1576 pprTcGblEnv :: TcGblEnv -> SDoc
1577 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1579 tcg_fam_insts = fam_insts,
1582 tcg_imports = imports })
1583 = vcat [ ppr_types insts type_env
1584 , ppr_tycons fam_insts type_env
1586 , ppr_fam_insts fam_insts
1587 , vcat (map ppr rules)
1588 , vcat (map ppr vects)
1589 , ppr_gen_tycons (typeEnvTyCons type_env)
1590 , ptext (sLit "Dependent modules:") <+>
1591 ppr (sortBy cmp_mp $ eltsUFM (imp_dep_mods imports))
1592 , ptext (sLit "Dependent packages:") <+>
1593 ppr (sortBy stablePackageIdCmp $ imp_dep_pkgs imports)]
1594 where -- The two uses of sortBy are just to reduce unnecessary
1595 -- wobbling in testsuite output
1596 cmp_mp (mod_name1, is_boot1) (mod_name2, is_boot2)
1597 = (mod_name1 `stableModuleNameCmp` mod_name2)
1599 (is_boot1 `compare` is_boot2)
1601 pprModGuts :: ModGuts -> SDoc
1602 pprModGuts (ModGuts { mg_types = type_env,
1604 = vcat [ ppr_types [] type_env,
1607 ppr_types :: [Instance] -> TypeEnv -> SDoc
1608 ppr_types insts type_env
1609 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1611 dfun_ids = map instanceDFunId insts
1612 ids = [id | id <- typeEnvIds type_env, want_sig id]
1613 want_sig id | opt_PprStyle_Debug = True
1614 | otherwise = isLocalId id &&
1615 isExternalName (idName id) &&
1616 not (id `elem` dfun_ids)
1617 -- isLocalId ignores data constructors, records selectors etc.
1618 -- The isExternalName ignores local dictionary and method bindings
1619 -- that the type checker has invented. Top-level user-defined things
1620 -- have External names.
1622 ppr_tycons :: [FamInst] -> TypeEnv -> SDoc
1623 ppr_tycons fam_insts type_env
1624 = text "TYPE CONSTRUCTORS" $$ nest 4 (ppr_tydecls tycons)
1626 fi_tycons = map famInstTyCon fam_insts
1627 tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
1628 want_tycon tycon | opt_PprStyle_Debug = True
1629 | otherwise = not (isImplicitTyCon tycon) &&
1630 isExternalName (tyConName tycon) &&
1631 not (tycon `elem` fi_tycons)
1633 ppr_insts :: [Instance] -> SDoc
1634 ppr_insts [] = empty
1635 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1637 ppr_fam_insts :: [FamInst] -> SDoc
1638 ppr_fam_insts [] = empty
1639 ppr_fam_insts fam_insts =
1640 text "FAMILY INSTANCES" $$ nest 2 (pprFamInsts fam_insts)
1642 ppr_sigs :: [Var] -> SDoc
1644 -- Print type signatures; sort by OccName
1645 = vcat (map ppr_sig (sortLe le_sig ids))
1647 le_sig id1 id2 = getOccName id1 <= getOccName id2
1648 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1650 ppr_tydecls :: [TyCon] -> SDoc
1652 -- Print type constructor info; sort by OccName
1653 = vcat (map ppr_tycon (sortLe le_sig tycons))
1655 le_sig tycon1 tycon2 = getOccName tycon1 <= getOccName tycon2
1657 | isCoercionTyCon tycon
1658 = sep [ptext (sLit "coercion") <+> ppr tycon <+> ppr tvs
1659 , nest 2 (dcolon <+> pprEqPred (coercionKind (mkTyConApp tycon (mkTyVarTys tvs))))]
1660 | otherwise = ppr (tyThingToIfaceDecl (ATyCon tycon))
1662 tvs = take (tyConArity tycon) alphaTyVars
1664 ppr_rules :: [CoreRule] -> SDoc
1665 ppr_rules [] = empty
1666 ppr_rules rs = vcat [ptext (sLit "{-# RULES"),
1667 nest 2 (pprRules rs),
1670 ppr_gen_tycons :: [TyCon] -> SDoc
1671 ppr_gen_tycons [] = empty
1672 ppr_gen_tycons tcs = vcat [ptext (sLit "Tycons with generics:"),
1673 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]