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 )
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
249 -- Check type-family consistency
250 ; traceRn (text "rn1: checking family instance consistency")
251 ; let { dir_imp_mods = moduleEnvKeys
254 ; checkFamInstConsistency (imp_finsts imports) dir_imp_mods ;
260 %************************************************************************
262 Type-checking external-core modules
264 %************************************************************************
267 tcRnExtCore :: HscEnv
269 -> IO (Messages, Maybe ModGuts)
270 -- Nothing => some error occurred
272 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
273 -- The decls are IfaceDecls; all names are original names
274 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
276 initTc hsc_env ExtCoreFile False this_mod $ do {
278 let { ldecls = map noLoc decls } ;
280 -- bring the type and class decls into scope
281 -- ToDo: check that this doesn't need to extract the val binds.
282 -- It seems that only the type and class decls need to be in scope below because
283 -- (a) tcTyAndClassDecls doesn't need the val binds, and
284 -- (b) tcExtCoreBindings doesn't need anything
285 -- (in fact, it might not even need to be in the scope of
286 -- this tcg_env at all)
287 avails <- getLocalNonValBinders (mkFakeGroup ldecls) ;
288 tc_envs <- extendGlobalRdrEnvRn avails emptyFsEnv {- no fixity decls -} ;
290 setEnvs tc_envs $ do {
292 (rn_decls, _fvs) <- checkNoErrs $ rnTyClDecls [ldecls] ;
294 -- Dump trace of renaming part
295 rnDump (ppr rn_decls) ;
297 -- Typecheck them all together so that
298 -- any mutually recursive types are done right
299 -- Just discard the auxiliary bindings; they are generated
300 -- only for Haskell source code, and should already be in Core
301 (tcg_env, _aux_binds) <- tcTyAndClassDecls emptyModDetails rn_decls ;
303 setGblEnv tcg_env $ do {
304 -- Make the new type env available to stuff slurped from interface files
306 -- Now the core bindings
307 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
311 bndrs = bindersOfBinds core_binds ;
312 my_exports = map (Avail . idName) bndrs ;
313 -- ToDo: export the data types also?
316 extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
318 mod_guts = ModGuts { mg_module = this_mod,
320 mg_used_names = emptyNameSet, -- ToDo: compute usage
321 mg_dir_imps = emptyModuleEnv, -- ??
322 mg_deps = noDependencies, -- ??
323 mg_exports = my_exports,
324 mg_types = final_type_env,
325 mg_insts = tcg_insts tcg_env,
326 mg_fam_insts = tcg_fam_insts tcg_env,
327 mg_inst_env = tcg_inst_env tcg_env,
328 mg_fam_inst_env = tcg_fam_inst_env tcg_env,
332 mg_binds = core_binds,
335 mg_rdr_env = emptyGlobalRdrEnv,
336 mg_fix_env = emptyFixityEnv,
337 mg_warns = NoWarnings,
338 mg_foreign = NoStubs,
339 mg_hpc_info = emptyHpcInfo False,
340 mg_modBreaks = emptyModBreaks,
341 mg_vect_info = noVectInfo
344 tcCoreDump mod_guts ;
349 mkFakeGroup :: [LTyClDecl a] -> HsGroup a
350 mkFakeGroup decls -- Rather clumsy; lots of unused fields
351 = emptyRdrGroup { hs_tyclds = [decls] }
355 %************************************************************************
357 Type-checking the top level of a module
359 %************************************************************************
362 tcRnSrcDecls :: ModDetails -> [LHsDecl RdrName] -> TcM TcGblEnv
363 -- Returns the variables free in the decls
364 -- Reason: solely to report unused imports and bindings
365 tcRnSrcDecls boot_iface decls
366 = do { -- Do all the declarations
367 (tc_envs, lie) <- captureConstraints $ tc_rn_src_decls boot_iface decls ;
368 ; traceTc "Tc8" empty ;
372 -- Finish simplifying class constraints
374 -- simplifyTop deals with constant or ambiguous InstIds.
375 -- How could there be ambiguous ones? They can only arise if a
376 -- top-level decl falls under the monomorphism restriction
377 -- and no subsequent decl instantiates its type.
379 -- We do this after checkMain, so that we use the type info
380 -- thaat checkMain adds
382 -- We do it with both global and local env in scope:
383 -- * the global env exposes the instances to simplifyTop
384 -- * the local env exposes the local Ids to simplifyTop,
385 -- so that we get better error messages (monomorphism restriction)
386 new_ev_binds <- simplifyTop lie ;
387 traceTc "Tc9" empty ;
389 failIfErrsM ; -- Don't zonk if there have been errors
390 -- It's a waste of time; and we may get debug warnings
391 -- about strangely-typed TyCons!
393 -- Zonk the final code. This must be done last.
394 -- Even simplifyTop may do some unification.
395 -- This pass also warns about missing type signatures
396 let { (tcg_env, _) = tc_envs
397 ; TcGblEnv { tcg_type_env = type_env,
400 tcg_ev_binds = cur_ev_binds,
401 tcg_imp_specs = imp_specs,
404 tcg_fords = fords } = tcg_env
405 ; all_ev_binds = cur_ev_binds `unionBags` new_ev_binds } ;
407 (bind_ids, ev_binds', binds', fords', imp_specs', rules', vects')
408 <- zonkTopDecls all_ev_binds binds sig_ns rules vects imp_specs fords ;
410 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
411 ; tcg_env' = tcg_env { tcg_binds = binds',
412 tcg_ev_binds = ev_binds',
413 tcg_imp_specs = imp_specs',
416 tcg_fords = fords' } } ;
418 setGlobalTypeEnv tcg_env' final_type_env
421 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
422 -- Loops around dealing with each top level inter-splice group
423 -- in turn, until it's dealt with the entire module
424 tc_rn_src_decls boot_details ds
425 = do { (first_group, group_tail) <- findSplice ds ;
426 -- If ds is [] we get ([], Nothing)
428 -- Deal with decls up to, but not including, the first splice
429 (tcg_env, rn_decls) <- rnTopSrcDecls first_group ;
430 -- rnTopSrcDecls fails if there are any errors
432 (tcg_env, tcl_env) <- setGblEnv tcg_env $
433 tcTopSrcDecls boot_details rn_decls ;
435 -- If there is no splice, we're nearly done
436 setEnvs (tcg_env, tcl_env) $
438 Nothing -> do { tcg_env <- checkMain ; -- Check for `main'
439 return (tcg_env, tcl_env)
443 -- There shouldn't be a splice
444 Just (SpliceDecl {}, _) -> do {
445 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
447 -- If there's a splice, we must carry on
448 Just (SpliceDecl splice_expr _, rest_ds) -> do {
450 -- Rename the splice expression, and get its supporting decls
451 (rn_splice_expr, splice_fvs) <- checkNoErrs (rnLExpr splice_expr) ;
452 -- checkNoErrs: don't typecheck if renaming failed
453 rnDump (ppr rn_splice_expr) ;
455 -- Execute the splice
456 spliced_decls <- tcSpliceDecls rn_splice_expr ;
458 -- Glue them on the front of the remaining decls and loop
459 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
460 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
465 %************************************************************************
467 Compiling hs-boot source files, and
468 comparing the hi-boot interface with the real thing
470 %************************************************************************
473 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
474 tcRnHsBootDecls decls
475 = do { (first_group, group_tail) <- findSplice decls
477 -- Rename the declarations
478 ; (tcg_env, HsGroup {
479 hs_tyclds = tycl_decls,
480 hs_instds = inst_decls,
481 hs_derivds = deriv_decls,
482 hs_fords = for_decls,
483 hs_defds = def_decls,
484 hs_ruleds = rule_decls,
485 hs_vects = vect_decls,
487 hs_valds = val_binds }) <- rnTopSrcDecls first_group
488 ; (gbl_env, lie) <- captureConstraints $ setGblEnv tcg_env $ do {
491 -- Check for illegal declarations
493 Just (SpliceDecl d _, _) -> badBootDecl "splice" d
495 ; mapM_ (badBootDecl "foreign") for_decls
496 ; mapM_ (badBootDecl "default") def_decls
497 ; mapM_ (badBootDecl "rule") rule_decls
498 ; mapM_ (badBootDecl "vect") vect_decls
500 -- Typecheck type/class decls
501 ; traceTc "Tc2" empty
502 ; (tcg_env, aux_binds)
503 <- tcTyAndClassDecls emptyModDetails tycl_decls
504 ; setGblEnv tcg_env $ do {
506 -- Typecheck instance decls
507 -- Family instance declarations are rejected here
508 ; traceTc "Tc3" empty
509 ; (tcg_env, inst_infos, _deriv_binds)
510 <- tcInstDecls1 (concat tycl_decls) inst_decls deriv_decls
512 ; setGblEnv tcg_env $ do {
514 -- Typecheck value declarations
515 ; traceTc "Tc5" empty
516 ; val_ids <- tcHsBootSigs val_binds
519 -- No simplification or zonking to do
520 ; traceTc "Tc7a" empty
521 ; gbl_env <- getGblEnv
523 -- Make the final type-env
524 -- Include the dfun_ids so that their type sigs
525 -- are written into the interface file.
526 -- And similarly the aux_ids from aux_binds
527 ; let { type_env0 = tcg_type_env gbl_env
528 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
529 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
530 ; type_env3 = extendTypeEnvWithIds type_env2 aux_ids
531 ; dfun_ids = map iDFunId inst_infos
532 ; aux_ids = case aux_binds of
533 ValBindsOut _ sigs -> [id | L _ (IdSig id) <- sigs]
534 _ -> panic "tcRnHsBoodDecls"
537 ; setGlobalTypeEnv gbl_env type_env3
539 ; traceTc "boot" (ppr lie); return gbl_env }
541 badBootDecl :: String -> Located decl -> TcM ()
542 badBootDecl what (L loc _)
543 = addErrAt loc (char 'A' <+> text what
544 <+> ptext (sLit "declaration is not (currently) allowed in a hs-boot file"))
547 Once we've typechecked the body of the module, we want to compare what
548 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
551 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM TcGblEnv
552 -- Compare the hi-boot file for this module (if there is one)
553 -- with the type environment we've just come up with
554 -- In the common case where there is no hi-boot file, the list
555 -- of boot_names is empty.
557 -- The bindings we return give bindings for the dfuns defined in the
558 -- hs-boot file, such as $fbEqT = $fEqT
561 tcg_env@(TcGblEnv { tcg_src = hs_src, tcg_binds = binds,
562 tcg_insts = local_insts,
563 tcg_type_env = local_type_env, tcg_exports = local_exports })
564 (ModDetails { md_insts = boot_insts, md_fam_insts = boot_fam_insts,
565 md_types = boot_type_env, md_exports = boot_exports })
566 | isHsBoot hs_src -- Current module is already a hs-boot file!
570 = do { traceTc "checkHiBootIface" $ vcat
571 [ ppr boot_type_env, ppr boot_insts, ppr boot_exports]
573 -- Check the exports of the boot module, one by one
574 ; mapM_ check_export boot_exports
576 -- Check for no family instances
577 ; unless (null boot_fam_insts) $
578 panic ("TcRnDriver.checkHiBootIface: Cannot handle family " ++
579 "instances in boot files yet...")
580 -- FIXME: Why? The actual comparison is not hard, but what would
581 -- be the equivalent to the dfun bindings returned for class
582 -- instances? We can't easily equate tycons...
584 -- Check instance declarations
585 ; mb_dfun_prs <- mapM check_inst boot_insts
586 ; let dfun_prs = catMaybes mb_dfun_prs
587 boot_dfuns = map fst dfun_prs
588 dfun_binds = listToBag [ mkVarBind boot_dfun (nlHsVar dfun)
589 | (boot_dfun, dfun) <- dfun_prs ]
590 type_env' = extendTypeEnvWithIds local_type_env boot_dfuns
591 tcg_env' = tcg_env { tcg_binds = binds `unionBags` dfun_binds }
594 ; setGlobalTypeEnv tcg_env' type_env' }
595 -- Update the global type env *including* the knot-tied one
596 -- so that if the source module reads in an interface unfolding
597 -- mentioning one of the dfuns from the boot module, then it
598 -- can "see" that boot dfun. See Trac #4003
600 check_export boot_avail -- boot_avail is exported by the boot iface
601 | name `elem` dfun_names = return ()
602 | isWiredInName name = return () -- No checking for wired-in names. In particular,
603 -- 'error' is handled by a rather gross hack
604 -- (see comments in GHC.Err.hs-boot)
606 -- Check that the actual module exports the same thing
607 | not (null missing_names)
608 = addErrAt (nameSrcSpan (head missing_names))
609 (missingBootThing (head missing_names) "exported by")
611 -- If the boot module does not *define* the thing, we are done
612 -- (it simply re-exports it, and names match, so nothing further to do)
613 | isNothing mb_boot_thing = return ()
615 -- Check that the actual module also defines the thing, and
616 -- then compare the definitions
617 | Just real_thing <- lookupTypeEnv local_type_env name,
618 Just boot_thing <- mb_boot_thing
619 = when (not (checkBootDecl boot_thing real_thing))
620 $ addErrAt (nameSrcSpan (getName boot_thing))
621 (let boot_decl = tyThingToIfaceDecl
622 (fromJust mb_boot_thing)
623 real_decl = tyThingToIfaceDecl real_thing
624 in bootMisMatch real_thing boot_decl real_decl)
627 = addErrTc (missingBootThing name "defined in")
629 name = availName boot_avail
630 mb_boot_thing = lookupTypeEnv boot_type_env name
631 missing_names = case lookupNameEnv local_export_env name of
633 Just avail -> availNames boot_avail `minusList` availNames avail
635 dfun_names = map getName boot_insts
637 local_export_env :: NameEnv AvailInfo
638 local_export_env = availsToNameEnv local_exports
640 check_inst :: Instance -> TcM (Maybe (Id, Id))
641 -- Returns a pair of the boot dfun in terms of the equivalent real dfun
643 = case [dfun | inst <- local_insts,
644 let dfun = instanceDFunId inst,
645 idType dfun `eqType` boot_inst_ty ] of
646 [] -> do { traceTc "check_inst" (vcat [ text "local_insts" <+> vcat (map (ppr . idType . instanceDFunId) local_insts)
647 , text "boot_inst" <+> ppr boot_inst
648 , text "boot_inst_ty" <+> ppr boot_inst_ty
650 ; addErrTc (instMisMatch boot_inst); return Nothing }
651 (dfun:_) -> return (Just (local_boot_dfun, dfun))
653 boot_dfun = instanceDFunId boot_inst
654 boot_inst_ty = idType boot_dfun
655 local_boot_dfun = Id.mkExportedLocalId (idName boot_dfun) boot_inst_ty
658 -- This has to compare the TyThing from the .hi-boot file to the TyThing
659 -- in the current source file. We must be careful to allow alpha-renaming
660 -- where appropriate, and also the boot declaration is allowed to omit
661 -- constructors and class methods.
663 -- See rnfail055 for a good test of this stuff.
665 checkBootDecl :: TyThing -> TyThing -> Bool
667 checkBootDecl (AnId id1) (AnId id2)
669 (idType id1 `eqType` idType id2)
671 checkBootDecl (ATyCon tc1) (ATyCon tc2)
672 = checkBootTyCon tc1 tc2
674 checkBootDecl (AClass c1) (AClass c2)
676 (clas_tyvars1, clas_fds1, sc_theta1, _, ats1, op_stuff1)
677 = classExtraBigSig c1
678 (clas_tyvars2, clas_fds2, sc_theta2, _, ats2, op_stuff2)
679 = classExtraBigSig c2
681 env0 = mkRnEnv2 emptyInScopeSet
682 env = rnBndrs2 env0 clas_tyvars1 clas_tyvars2
684 eqSig (id1, def_meth1) (id2, def_meth2)
685 = idName id1 == idName id2 &&
686 eqTypeX env op_ty1 op_ty2 &&
687 def_meth1 == def_meth2
689 (_, rho_ty1) = splitForAllTys (idType id1)
690 op_ty1 = funResultTy rho_ty1
691 (_, rho_ty2) = splitForAllTys (idType id2)
692 op_ty2 = funResultTy rho_ty2
694 eqFD (as1,bs1) (as2,bs2) =
695 eqListBy (eqTypeX env) (mkTyVarTys as1) (mkTyVarTys as2) &&
696 eqListBy (eqTypeX env) (mkTyVarTys bs1) (mkTyVarTys bs2)
698 same_kind tv1 tv2 = eqKind (tyVarKind tv1) (tyVarKind tv2)
700 eqListBy same_kind clas_tyvars1 clas_tyvars2 &&
701 -- Checks kind of class
702 eqListBy eqFD clas_fds1 clas_fds2 &&
703 (null sc_theta1 && null op_stuff1 && null ats1
704 || -- Above tests for an "abstract" class
705 eqListBy (eqPredX env) sc_theta1 sc_theta2 &&
706 eqListBy eqSig op_stuff1 op_stuff2 &&
707 eqListBy checkBootTyCon ats1 ats2)
709 checkBootDecl (ADataCon dc1) (ADataCon _)
710 = pprPanic "checkBootDecl" (ppr dc1)
712 checkBootDecl _ _ = False -- probably shouldn't happen
715 checkBootTyCon :: TyCon -> TyCon -> Bool
716 checkBootTyCon tc1 tc2
717 | not (eqKind (tyConKind tc1) (tyConKind tc2))
718 = False -- First off, check the kind
720 | isSynTyCon tc1 && isSynTyCon tc2
722 let tvs1 = tyConTyVars tc1; tvs2 = tyConTyVars tc2
723 env = rnBndrs2 env0 tvs1 tvs2
725 eqSynRhs SynFamilyTyCon SynFamilyTyCon
727 eqSynRhs (SynonymTyCon t1) (SynonymTyCon t2)
731 equalLength tvs1 tvs2 &&
732 eqSynRhs (synTyConRhs tc1) (synTyConRhs tc2)
734 | isAlgTyCon tc1 && isAlgTyCon tc2
736 eqKind (tyConKind tc1) (tyConKind tc2) &&
737 eqListBy eqPred (tyConStupidTheta tc1) (tyConStupidTheta tc2) &&
738 eqAlgRhs (algTyConRhs tc1) (algTyConRhs tc2)
740 | isForeignTyCon tc1 && isForeignTyCon tc2
741 = eqKind (tyConKind tc1) (tyConKind tc2) &&
742 tyConExtName tc1 == tyConExtName tc2
746 env0 = mkRnEnv2 emptyInScopeSet
748 eqAlgRhs AbstractTyCon _ = True
749 eqAlgRhs DataFamilyTyCon{} DataFamilyTyCon{} = True
750 eqAlgRhs tc1@DataTyCon{} tc2@DataTyCon{} =
751 eqListBy eqCon (data_cons tc1) (data_cons tc2)
752 eqAlgRhs tc1@NewTyCon{} tc2@NewTyCon{} =
753 eqCon (data_con tc1) (data_con tc2)
757 = dataConName c1 == dataConName c2
758 && dataConIsInfix c1 == dataConIsInfix c2
759 && dataConStrictMarks c1 == dataConStrictMarks c2
760 && dataConFieldLabels c1 == dataConFieldLabels c2
761 && eqType (dataConUserType c1) (dataConUserType c2)
764 missingBootThing :: Name -> String -> SDoc
765 missingBootThing name what
766 = ppr name <+> ptext (sLit "is exported by the hs-boot file, but not")
767 <+> text what <+> ptext (sLit "the module")
769 bootMisMatch :: TyThing -> IfaceDecl -> IfaceDecl -> SDoc
770 bootMisMatch thing boot_decl real_decl
771 = vcat [ppr thing <+> ptext (sLit "has conflicting definitions in the module and its hs-boot file"),
772 ptext (sLit "Main module:") <+> ppr real_decl,
773 ptext (sLit "Boot file: ") <+> ppr boot_decl]
775 instMisMatch :: Instance -> SDoc
778 2 (ptext (sLit "is defined in the hs-boot file, but not in the module itself"))
782 %************************************************************************
784 Type-checking the top level of a module
786 %************************************************************************
788 tcRnGroup takes a bunch of top-level source-code declarations, and
790 * gets supporting declarations from interface files
793 * and augments the TcGblEnv with the results
795 In Template Haskell it may be called repeatedly for each group of
796 declarations. It expects there to be an incoming TcGblEnv in the
797 monad; it augments it and returns the new TcGblEnv.
800 ------------------------------------------------
801 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
802 -- Fails if there are any errors
804 = do { -- Rename the source decls
805 traceTc "rn12" empty ;
806 (tcg_env, rn_decls) <- checkNoErrs $ rnSrcDecls group ;
807 traceTc "rn13" empty ;
809 -- save the renamed syntax, if we want it
811 | Just grp <- tcg_rn_decls tcg_env
812 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
816 -- Dump trace of renaming part
817 rnDump (ppr rn_decls) ;
819 return (tcg_env', rn_decls)
822 ------------------------------------------------
823 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
824 tcTopSrcDecls boot_details
825 (HsGroup { hs_tyclds = tycl_decls,
826 hs_instds = inst_decls,
827 hs_derivds = deriv_decls,
828 hs_fords = foreign_decls,
829 hs_defds = default_decls,
830 hs_annds = annotation_decls,
831 hs_ruleds = rule_decls,
832 hs_vects = vect_decls,
833 hs_valds = val_binds })
834 = do { -- Type-check the type and class decls, and all imported decls
835 -- The latter come in via tycl_decls
836 traceTc "Tc2" empty ;
838 (tcg_env, aux_binds) <- tcTyAndClassDecls boot_details tycl_decls ;
839 -- If there are any errors, tcTyAndClassDecls fails here
841 setGblEnv tcg_env $ do {
843 -- Source-language instances, including derivings,
844 -- and import the supporting declarations
845 traceTc "Tc3" empty ;
846 (tcg_env, inst_infos, deriv_binds)
847 <- tcInstDecls1 (concat tycl_decls) inst_decls deriv_decls;
848 setGblEnv tcg_env $ do {
850 -- Foreign import declarations next.
851 traceTc "Tc4" empty ;
852 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
853 tcExtendGlobalValEnv fi_ids $ do {
855 -- Default declarations
856 traceTc "Tc4a" empty ;
857 default_tys <- tcDefaults default_decls ;
858 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
860 -- Now GHC-generated derived bindings, generics, and selectors
861 -- Do not generate warnings from compiler-generated code;
862 -- hence the use of discardWarnings
863 (tc_aux_binds, specs1, tcl_env) <- discardWarnings (tcTopBinds aux_binds) ;
864 (tc_deriv_binds, specs2, tcl_env) <- setLclTypeEnv tcl_env $
865 discardWarnings (tcTopBinds deriv_binds) ;
867 -- Value declarations next
868 traceTc "Tc5" empty ;
869 (tc_val_binds, specs3, tcl_env) <- setLclTypeEnv tcl_env $
870 tcTopBinds val_binds;
872 setLclTypeEnv tcl_env $ do { -- Environment doesn't change now
874 -- Second pass over class and instance declarations,
875 -- now using the kind-checked decls
876 traceTc "Tc6" empty ;
877 inst_binds <- tcInstDecls2 (concat tycl_decls) inst_infos ;
880 traceTc "Tc7" empty ;
881 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
884 annotations <- tcAnnotations annotation_decls ;
887 rules <- tcRules rule_decls ;
889 -- Vectorisation declarations
890 vects <- tcVectDecls vect_decls ;
893 traceTc "Tc7a" empty ;
894 tcg_env <- getGblEnv ;
895 let { all_binds = tc_val_binds `unionBags`
896 tc_deriv_binds `unionBags`
897 tc_aux_binds `unionBags`
898 inst_binds `unionBags`
901 ; sig_names = mkNameSet (collectHsValBinders val_binds)
902 `minusNameSet` getTypeSigNames val_binds
904 -- Extend the GblEnv with the (as yet un-zonked)
905 -- bindings, rules, foreign decls
906 ; tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds
907 , tcg_imp_specs = tcg_imp_specs tcg_env ++ specs1 ++ specs2 ++
909 , tcg_sigs = tcg_sigs tcg_env `unionNameSets` sig_names
910 , tcg_rules = tcg_rules tcg_env ++ rules
911 , tcg_vects = tcg_vects tcg_env ++ vects
912 , tcg_anns = tcg_anns tcg_env ++ annotations
913 , tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
914 return (tcg_env', tcl_env)
919 %************************************************************************
923 %************************************************************************
926 checkMain :: TcM TcGblEnv
927 -- If we are in module Main, check that 'main' is defined.
929 = do { tcg_env <- getGblEnv ;
931 check_main dflags tcg_env
934 check_main :: DynFlags -> TcGblEnv -> TcM TcGblEnv
935 check_main dflags tcg_env
937 = traceTc "checkMain not" (ppr main_mod <+> ppr mod) >>
941 = do { mb_main <- lookupGlobalOccRn_maybe main_fn
942 -- Check that 'main' is in scope
943 -- It might be imported from another module!
945 Nothing -> do { traceTc "checkMain fail" (ppr main_mod <+> ppr main_fn)
950 { traceTc "checkMain found" (ppr main_mod <+> ppr main_fn)
951 ; let loc = srcLocSpan (getSrcLoc main_name)
952 ; ioTyCon <- tcLookupTyCon ioTyConName
953 ; res_ty <- newFlexiTyVarTy liftedTypeKind
955 <- addErrCtxt mainCtxt $
956 tcMonoExpr (L loc (HsVar main_name)) (mkTyConApp ioTyCon [res_ty])
958 -- See Note [Root-main Id]
959 -- Construct the binding
960 -- :Main.main :: IO res_ty = runMainIO res_ty main
961 ; run_main_id <- tcLookupId runMainIOName
962 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
963 (mkVarOccFS (fsLit "main"))
964 (getSrcSpan main_name)
965 ; root_main_id = Id.mkExportedLocalId root_main_name
966 (mkTyConApp ioTyCon [res_ty])
967 ; co = mkWpTyApps [res_ty]
968 ; rhs = nlHsApp (mkLHsWrap co (nlHsVar run_main_id)) main_expr
969 ; main_bind = mkVarBind root_main_id rhs }
971 ; return (tcg_env { tcg_main = Just main_name,
972 tcg_binds = tcg_binds tcg_env
974 tcg_dus = tcg_dus tcg_env
975 `plusDU` usesOnly (unitFV main_name)
976 -- Record the use of 'main', so that we don't
977 -- complain about it being defined but not used
981 mod = tcg_mod tcg_env
982 main_mod = mainModIs dflags
983 main_fn = getMainFun dflags
985 complain_no_main | ghcLink dflags == LinkInMemory = return ()
986 | otherwise = failWithTc noMainMsg
987 -- In interactive mode, don't worry about the absence of 'main'
988 -- In other modes, fail altogether, so that we don't go on
989 -- and complain a second time when processing the export list.
991 mainCtxt = ptext (sLit "When checking the type of the") <+> pp_main_fn
992 noMainMsg = ptext (sLit "The") <+> pp_main_fn
993 <+> ptext (sLit "is not defined in module") <+> quotes (ppr main_mod)
994 pp_main_fn = ppMainFn main_fn
996 ppMainFn :: RdrName -> SDoc
998 | main_fn == main_RDR_Unqual
999 = ptext (sLit "function") <+> quotes (ppr main_fn)
1001 = ptext (sLit "main function") <+> quotes (ppr main_fn)
1003 -- | Get the unqualified name of the function to use as the \"main\" for the main module.
1004 -- Either returns the default name or the one configured on the command line with -main-is
1005 getMainFun :: DynFlags -> RdrName
1006 getMainFun dflags = case (mainFunIs dflags) of
1007 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn))
1008 Nothing -> main_RDR_Unqual
1010 checkMainExported :: TcGblEnv -> TcM ()
1011 checkMainExported tcg_env = do
1013 case tcg_main tcg_env of
1014 Nothing -> return () -- not the main module
1015 Just main_name -> do
1016 let main_mod = mainModIs dflags
1017 checkTc (main_name `elem` concatMap availNames (tcg_exports tcg_env)) $
1018 ptext (sLit "The") <+> ppMainFn (nameRdrName main_name) <+>
1019 ptext (sLit "is not exported by module") <+> quotes (ppr main_mod)
1024 The function that the RTS invokes is always :Main.main, which we call
1025 root_main_id. (Because GHC allows the user to have a module not
1026 called Main as the main module, we can't rely on the main function
1027 being called "Main.main". That's why root_main_id has a fixed module
1030 This is unusual: it's a LocalId whose Name has a Module from another
1031 module. Tiresomely, we must filter it out again in MkIface, les we
1032 get two defns for 'main' in the interface file!
1035 %*********************************************************
1039 %*********************************************************
1042 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
1043 setInteractiveContext hsc_env icxt thing_inside
1044 = let -- Initialise the tcg_inst_env with instances from all home modules.
1045 -- This mimics the more selective call to hptInstances in tcRnModule.
1046 (home_insts, home_fam_insts) = hptInstances hsc_env (\_ -> True)
1048 updGblEnv (\env -> env {
1049 tcg_rdr_env = ic_rn_gbl_env icxt,
1050 tcg_inst_env = extendInstEnvList (tcg_inst_env env) home_insts,
1051 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env env)
1055 tcExtendGhciEnv (ic_tmp_ids icxt) $
1056 -- tcExtendGhciEnv does lots:
1057 -- - it extends the local type env (tcl_env) with the given Ids,
1058 -- - it extends the local rdr env (tcl_rdr) with the Names from
1060 -- - it adds the free tyvars of the Ids to the tcl_tyvars
1063 -- later ids in ic_tmp_ids must shadow earlier ones with the same
1064 -- OccName, and tcExtendIdEnv implements this behaviour.
1066 do { traceTc "setIC" (ppr (ic_tmp_ids icxt))
1074 -> InteractiveContext
1076 -> IO (Messages, Maybe ([Id], LHsExpr Id))
1077 -- The returned [Id] is the list of new Ids bound by
1078 -- this statement. It can be used to extend the
1079 -- InteractiveContext via extendInteractiveContext.
1081 -- The returned TypecheckedHsExpr is of type IO [ () ],
1082 -- a list of the bound values, coerced to ().
1084 tcRnStmt hsc_env ictxt rdr_stmt
1085 = initTcPrintErrors hsc_env iNTERACTIVE $
1086 setInteractiveContext hsc_env ictxt $ do {
1088 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
1089 (([rn_stmt], _), fvs) <- rnStmts GhciStmt [rdr_stmt] $ \_ ->
1090 return ((), emptyFVs) ;
1091 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
1093 rnDump (ppr rn_stmt) ;
1095 -- The real work is done here
1096 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
1097 zonked_expr <- zonkTopLExpr tc_expr ;
1098 zonked_ids <- zonkTopBndrs bound_ids ;
1100 -- None of the Ids should be of unboxed type, because we
1101 -- cast them all to HValues in the end!
1102 mapM_ bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
1104 traceTc "tcs 1" empty ;
1105 let { global_ids = map globaliseAndTidyId zonked_ids } ;
1106 -- Note [Interactively-bound Ids in GHCi]
1108 {- ---------------------------------------------
1109 At one stage I removed any shadowed bindings from the type_env;
1110 they are inaccessible but might, I suppose, cause a space leak if we leave them there.
1111 However, with Template Haskell they aren't necessarily inaccessible. Consider this
1113 Prelude> let f n = n * 2 :: Int
1114 Prelude> fName <- runQ [| f |]
1115 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1117 Prelude> let f n = n * 3 :: Int
1118 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1119 In the last line we use 'fName', which resolves to the *first* 'f'
1120 in scope. If we delete it from the type env, GHCi crashes because
1121 it doesn't expect that.
1123 Hence this code is commented out
1125 -------------------------------------------------- -}
1127 dumpOptTcRn Opt_D_dump_tc
1128 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
1129 text "Typechecked expr" <+> ppr zonked_expr]) ;
1131 return (global_ids, zonked_expr)
1134 bad_unboxed id = addErr (sep [ptext (sLit "GHCi can't bind a variable of unlifted type:"),
1135 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
1138 Note [Interactively-bound Ids in GHCi]
1139 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1140 The Ids bound by previous Stmts in Template Haskell are currently
1142 b) with an Internal Name (not External)
1143 c) and a tidied type
1145 (a) They must be GlobalIds (not LocalIds) otherwise when we come to
1146 compile an expression using these ids later, the byte code
1147 generator will consider the occurrences to be free rather than
1150 (b) They retain their Internal names becuase we don't have a suitable
1151 Module to name them with. We could revisit this choice.
1153 (c) Their types are tidied. This is important, because :info may ask
1154 to look at them, and :info expects the things it looks up to have
1158 --------------------------------------------------------------------------
1159 Typechecking Stmts in GHCi
1161 Here is the grand plan, implemented in tcUserStmt
1163 What you type The IO [HValue] that hscStmt returns
1164 ------------- ------------------------------------
1165 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
1168 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
1171 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
1172 [NB: result not printed] bindings: [it]
1174 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
1175 result showable) bindings: [it]
1177 expr (of non-IO type,
1178 result not showable) ==> error
1182 ---------------------------
1183 type PlanResult = ([Id], LHsExpr Id)
1184 type Plan = TcM PlanResult
1186 runPlans :: [Plan] -> TcM PlanResult
1187 -- Try the plans in order. If one fails (by raising an exn), try the next.
1188 -- If one succeeds, take it.
1189 runPlans [] = panic "runPlans"
1191 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
1193 --------------------
1194 mkPlan :: LStmt Name -> TcM PlanResult
1195 mkPlan (L loc (ExprStmt expr _ _ _)) -- An expression typed at the prompt
1196 = do { uniq <- newUnique -- is treated very specially
1197 ; let fresh_it = itName uniq
1198 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
1199 matches = [mkMatch [] expr emptyLocalBinds]
1200 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
1201 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
1202 (HsVar bindIOName) noSyntaxExpr
1203 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
1204 (HsVar thenIOName) noSyntaxExpr placeHolderType
1207 -- [it <- e; print it] but not if it::()
1209 -- [let it = e; print it]
1210 ; runPlans [ -- Plan A
1211 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
1212 ; it_ty <- zonkTcType (idType it_id)
1213 ; when (isUnitTy it_ty) failM
1216 -- Plan B; a naked bind statment
1217 tcGhciStmts [bind_stmt],
1219 -- Plan C; check that the let-binding is typeable all by itself.
1220 -- If not, fail; if so, try to print it.
1221 -- The two-step process avoids getting two errors: one from
1222 -- the expression itself, and one from the 'print it' part
1223 -- This two-step story is very clunky, alas
1224 do { _ <- checkNoErrs (tcGhciStmts [let_stmt])
1225 --- checkNoErrs defeats the error recovery of let-bindings
1226 ; tcGhciStmts [let_stmt, print_it] }
1229 mkPlan stmt@(L loc (BindStmt {}))
1230 | [v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
1231 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
1232 (HsVar thenIOName) noSyntaxExpr placeHolderType
1234 ; print_bind_result <- doptM Opt_PrintBindResult
1235 ; let print_plan = do
1236 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
1237 ; v_ty <- zonkTcType (idType v_id)
1238 ; when (isUnitTy v_ty || not (isTauTy v_ty)) failM
1242 -- [stmt; print v] but not if v::()
1244 ; runPlans ((if print_bind_result then [print_plan] else []) ++
1245 [tcGhciStmts [stmt]])
1249 = tcGhciStmts [stmt]
1251 ---------------------------
1252 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1254 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1255 ret_id <- tcLookupId returnIOName ; -- return @ IO
1257 ret_ty = mkListTy unitTy ;
1258 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1259 tc_io_stmts stmts = tcStmtsAndThen GhciStmt tcDoStmt stmts io_ret_ty ;
1260 names = collectLStmtsBinders stmts ;
1263 -- OK, we're ready to typecheck the stmts
1264 traceTc "TcRnDriver.tcGhciStmts: tc stmts" empty ;
1265 ((tc_stmts, ids), lie) <- captureConstraints $
1266 tc_io_stmts stmts $ \ _ ->
1267 mapM tcLookupId names ;
1268 -- Look up the names right in the middle,
1269 -- where they will all be in scope
1271 -- Simplify the context
1272 traceTc "TcRnDriver.tcGhciStmts: simplify ctxt" empty ;
1273 const_binds <- checkNoErrs (simplifyInteractive lie) ;
1274 -- checkNoErrs ensures that the plan fails if context redn fails
1276 traceTc "TcRnDriver.tcGhciStmts: done" empty ;
1277 let { -- mk_return builds the expression
1278 -- returnIO @ [()] [coerce () x, .., coerce () z]
1280 -- Despite the inconvenience of building the type applications etc,
1281 -- this *has* to be done in type-annotated post-typecheck form
1282 -- because we are going to return a list of *polymorphic* values
1283 -- coerced to type (). If we built a *source* stmt
1284 -- return [coerce x, ..., coerce z]
1285 -- then the type checker would instantiate x..z, and we wouldn't
1286 -- get their *polymorphic* values. (And we'd get ambiguity errs
1287 -- if they were overloaded, since they aren't applied to anything.)
1288 ret_expr = nlHsApp (nlHsTyApp ret_id [ret_ty])
1289 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1290 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1292 stmts = tc_stmts ++ [noLoc (mkLastStmt ret_expr)]
1294 return (ids, mkHsDictLet (EvBinds const_binds) $
1295 noLoc (HsDo GhciStmt stmts io_ret_ty))
1300 tcRnExpr just finds the type of an expression
1304 -> InteractiveContext
1306 -> IO (Messages, Maybe Type)
1307 tcRnExpr hsc_env ictxt rdr_expr
1308 = initTcPrintErrors hsc_env iNTERACTIVE $
1309 setInteractiveContext hsc_env ictxt $ do {
1311 (rn_expr, _fvs) <- rnLExpr rdr_expr ;
1314 -- Now typecheck the expression;
1315 -- it might have a rank-2 type (e.g. :t runST)
1317 let { fresh_it = itName uniq } ;
1318 ((_tc_expr, res_ty), lie) <- captureConstraints (tcInferRho rn_expr) ;
1319 ((qtvs, dicts, _), lie_top) <- captureConstraints $
1320 simplifyInfer TopLevel False {- No MR for now -}
1321 [(fresh_it, res_ty)]
1323 _ <- simplifyInteractive lie_top ; -- Ignore the dicionary bindings
1325 let { all_expr_ty = mkForAllTys qtvs (mkPiTypes dicts res_ty) } ;
1326 zonkTcType all_expr_ty
1330 tcRnType just finds the kind of a type
1334 -> InteractiveContext
1336 -> IO (Messages, Maybe Kind)
1337 tcRnType hsc_env ictxt rdr_type
1338 = initTcPrintErrors hsc_env iNTERACTIVE $
1339 setInteractiveContext hsc_env ictxt $ do {
1341 rn_type <- rnLHsType doc rdr_type ;
1344 -- Now kind-check the type
1345 (_ty', kind) <- kcLHsType rn_type ;
1349 doc = ptext (sLit "In GHCi input")
1355 %************************************************************************
1357 More GHCi stuff, to do with browsing and getting info
1359 %************************************************************************
1363 -- | ASSUMES that the module is either in the 'HomePackageTable' or is
1364 -- a package module with an interface on disk. If neither of these is
1365 -- true, then the result will be an error indicating the interface
1366 -- could not be found.
1367 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe [AvailInfo])
1368 getModuleExports hsc_env mod
1369 = initTc hsc_env HsSrcFile False iNTERACTIVE (tcGetModuleExports mod)
1371 -- Get the export avail info and also load all orphan and family-instance
1372 -- modules. Finally, check that the family instances of all modules in the
1373 -- interactive context are consistent (these modules are in the second
1375 tcGetModuleExports :: Module -> TcM [AvailInfo]
1376 tcGetModuleExports mod
1377 = do { let doc = ptext (sLit "context for compiling statements")
1378 ; iface <- initIfaceTcRn $ loadSysInterface doc mod
1380 -- Load any orphan-module and family instance-module
1381 -- interfaces, so their instances are visible.
1382 ; loadOrphanModules (dep_orphs (mi_deps iface)) False
1384 ; ifaceExportNames (mi_exports iface)
1387 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Messages, Maybe [Name])
1388 tcRnLookupRdrName hsc_env rdr_name
1389 = initTcPrintErrors hsc_env iNTERACTIVE $
1390 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1391 lookup_rdr_name rdr_name
1393 lookup_rdr_name :: RdrName -> TcM [Name]
1394 lookup_rdr_name rdr_name = do {
1395 -- If the identifier is a constructor (begins with an
1396 -- upper-case letter), then we need to consider both
1397 -- constructor and type class identifiers.
1398 let { rdr_names = dataTcOccs rdr_name } ;
1400 -- results :: [Either Messages Name]
1401 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1403 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1404 -- The successful lookups will be (Just name)
1405 let { (warns_s, good_names) = unzip [ (msgs, name)
1406 | (msgs, Just name) <- results] ;
1407 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1409 -- Fail if nothing good happened, else add warnings
1410 if null good_names then
1411 -- No lookup succeeded, so
1412 -- pick the first error message and report it
1413 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1414 -- while the other is "X is not in scope",
1415 -- we definitely want the former; but we might pick the latter
1416 do { addMessages (head errs_s) ; failM }
1417 else -- Add deprecation warnings
1418 mapM_ addMessages warns_s ;
1424 tcRnLookupName :: HscEnv -> Name -> IO (Messages, Maybe TyThing)
1425 tcRnLookupName hsc_env name
1426 = initTcPrintErrors hsc_env iNTERACTIVE $
1427 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1428 tcRnLookupName' name
1430 -- To look up a name we have to look in the local environment (tcl_lcl)
1431 -- as well as the global environment, which is what tcLookup does.
1432 -- But we also want a TyThing, so we have to convert:
1434 tcRnLookupName' :: Name -> TcRn TyThing
1435 tcRnLookupName' name = do
1436 tcthing <- tcLookup name
1438 AGlobal thing -> return thing
1439 ATcId{tct_id=id} -> return (AnId id)
1440 _ -> panic "tcRnLookupName'"
1442 tcRnGetInfo :: HscEnv
1444 -> IO (Messages, Maybe (TyThing, Fixity, [Instance]))
1446 -- Used to implement :info in GHCi
1448 -- Look up a RdrName and return all the TyThings it might be
1449 -- A capitalised RdrName is given to us in the DataName namespace,
1450 -- but we want to treat it as *both* a data constructor
1451 -- *and* as a type or class constructor;
1452 -- hence the call to dataTcOccs, and we return up to two results
1453 tcRnGetInfo hsc_env name
1454 = initTcPrintErrors hsc_env iNTERACTIVE $
1455 tcRnGetInfo' hsc_env name
1457 tcRnGetInfo' :: HscEnv
1459 -> TcRn (TyThing, Fixity, [Instance])
1460 tcRnGetInfo' hsc_env name
1461 = let ictxt = hsc_IC hsc_env in
1462 setInteractiveContext hsc_env ictxt $ do
1464 -- Load the interface for all unqualified types and classes
1465 -- That way we will find all the instance declarations
1466 -- (Packages have not orphan modules, and we assume that
1467 -- in the home package all relevant modules are loaded.)
1468 loadUnqualIfaces ictxt
1470 thing <- tcRnLookupName' name
1471 fixity <- lookupFixityRn name
1472 ispecs <- lookupInsts thing
1473 return (thing, fixity, ispecs)
1475 lookupInsts :: TyThing -> TcM [Instance]
1476 lookupInsts (AClass cls)
1477 = do { inst_envs <- tcGetInstEnvs
1478 ; return (classInstances inst_envs cls) }
1480 lookupInsts (ATyCon tc)
1481 = do { (pkg_ie, home_ie) <- tcGetInstEnvs
1482 -- Load all instances for all classes that are
1483 -- in the type environment (which are all the ones
1484 -- we've seen in any interface file so far)
1485 ; return [ ispec -- Search all
1486 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1487 , let dfun = instanceDFunId ispec
1490 relevant df = tc_name `elemNameSet` orphNamesOfDFunHead (idType df)
1491 tc_name = tyConName tc
1493 lookupInsts _ = return []
1495 loadUnqualIfaces :: InteractiveContext -> TcM ()
1496 -- Load the home module for everything that is in scope unqualified
1497 -- This is so that we can accurately report the instances for
1499 loadUnqualIfaces ictxt
1501 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1503 unqual_mods = [ nameModule name
1504 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1505 let name = gre_name gre,
1506 not (isInternalName name),
1507 isTcOcc (nameOccName name), -- Types and classes only
1508 unQualOK gre ] -- In scope unqualified
1509 doc = ptext (sLit "Need interface for module whose export(s) are in scope unqualified")
1512 %************************************************************************
1516 %************************************************************************
1519 rnDump :: SDoc -> TcRn ()
1520 -- Dump, with a banner, if -ddump-rn
1521 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1523 tcDump :: TcGblEnv -> TcRn ()
1525 = do { dflags <- getDOpts ;
1527 -- Dump short output if -ddump-types or -ddump-tc
1528 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1529 (dumpTcRn short_dump) ;
1531 -- Dump bindings if -ddump-tc
1532 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1535 short_dump = pprTcGblEnv env
1536 full_dump = pprLHsBinds (tcg_binds env)
1537 -- NB: foreign x-d's have undefined's in their types;
1538 -- hence can't show the tc_fords
1540 tcCoreDump :: ModGuts -> TcM ()
1542 = do { dflags <- getDOpts ;
1543 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1544 (dumpTcRn (pprModGuts mod_guts)) ;
1546 -- Dump bindings if -ddump-tc
1547 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1549 full_dump = pprCoreBindings (mg_binds mod_guts)
1551 -- It's unpleasant having both pprModGuts and pprModDetails here
1552 pprTcGblEnv :: TcGblEnv -> SDoc
1553 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1555 tcg_fam_insts = fam_insts,
1558 tcg_imports = imports })
1559 = vcat [ ppr_types insts type_env
1560 , ppr_tycons fam_insts type_env
1562 , ppr_fam_insts fam_insts
1563 , vcat (map ppr rules)
1564 , vcat (map ppr vects)
1565 , ptext (sLit "Dependent modules:") <+>
1566 ppr (sortBy cmp_mp $ eltsUFM (imp_dep_mods imports))
1567 , ptext (sLit "Dependent packages:") <+>
1568 ppr (sortBy stablePackageIdCmp $ imp_dep_pkgs imports)]
1569 where -- The two uses of sortBy are just to reduce unnecessary
1570 -- wobbling in testsuite output
1571 cmp_mp (mod_name1, is_boot1) (mod_name2, is_boot2)
1572 = (mod_name1 `stableModuleNameCmp` mod_name2)
1574 (is_boot1 `compare` is_boot2)
1576 pprModGuts :: ModGuts -> SDoc
1577 pprModGuts (ModGuts { mg_types = type_env,
1579 = vcat [ ppr_types [] type_env,
1582 ppr_types :: [Instance] -> TypeEnv -> SDoc
1583 ppr_types insts type_env
1584 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1586 dfun_ids = map instanceDFunId insts
1587 ids = [id | id <- typeEnvIds type_env, want_sig id]
1588 want_sig id | opt_PprStyle_Debug = True
1589 | otherwise = isLocalId id &&
1590 isExternalName (idName id) &&
1591 not (id `elem` dfun_ids)
1592 -- isLocalId ignores data constructors, records selectors etc.
1593 -- The isExternalName ignores local dictionary and method bindings
1594 -- that the type checker has invented. Top-level user-defined things
1595 -- have External names.
1597 ppr_tycons :: [FamInst] -> TypeEnv -> SDoc
1598 ppr_tycons fam_insts type_env
1599 = vcat [ text "TYPE CONSTRUCTORS"
1600 , nest 2 (ppr_tydecls tycons)
1601 , text "COERCION AXIOMS"
1602 , nest 2 (vcat (map pprCoAxiom (typeEnvCoAxioms type_env))) ]
1604 fi_tycons = map famInstTyCon fam_insts
1605 tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
1606 want_tycon tycon | opt_PprStyle_Debug = True
1607 | otherwise = not (isImplicitTyCon tycon) &&
1608 isExternalName (tyConName tycon) &&
1609 not (tycon `elem` fi_tycons)
1611 ppr_insts :: [Instance] -> SDoc
1612 ppr_insts [] = empty
1613 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1615 ppr_fam_insts :: [FamInst] -> SDoc
1616 ppr_fam_insts [] = empty
1617 ppr_fam_insts fam_insts =
1618 text "FAMILY INSTANCES" $$ nest 2 (pprFamInsts fam_insts)
1620 ppr_sigs :: [Var] -> SDoc
1622 -- Print type signatures; sort by OccName
1623 = vcat (map ppr_sig (sortLe le_sig ids))
1625 le_sig id1 id2 = getOccName id1 <= getOccName id2
1626 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1628 ppr_tydecls :: [TyCon] -> SDoc
1630 -- Print type constructor info; sort by OccName
1631 = vcat (map ppr_tycon (sortLe le_sig tycons))
1633 le_sig tycon1 tycon2 = getOccName tycon1 <= getOccName tycon2
1634 ppr_tycon tycon = ppr (tyThingToIfaceDecl (ATyCon tycon))
1636 ppr_rules :: [CoreRule] -> SDoc
1637 ppr_rules [] = empty
1638 ppr_rules rs = vcat [ptext (sLit "{-# RULES"),
1639 nest 2 (pprRules rs),