2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
5 \section[TcModule]{Typechecking a whole module}
9 -- The above warning supression flag is a temporary kludge.
10 -- While working on this module you are encouraged to remove it and fix
11 -- any warnings in the module. See
12 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
17 tcRnStmt, tcRnExpr, tcRnType,
30 import {-# SOURCE #-} TcSplice ( tcSpliceDecls )
60 import TcUnify ( withBox )
86 import Data.List ( sortBy )
98 import {- Kind parts of -} Type
100 import Foreign.Ptr( Ptr )
109 import Data.Maybe ( isJust )
111 #include "HsVersions.h"
116 %************************************************************************
118 Typecheck and rename a module
120 %************************************************************************
126 -> Bool -- True <=> save renamed syntax
127 -> Located (HsModule RdrName)
128 -> IO (Messages, Maybe TcGblEnv)
130 tcRnModule hsc_env hsc_src save_rn_syntax
131 (L loc (HsModule maybe_mod export_ies
132 import_decls local_decls mod_deprec
133 module_info maybe_doc))
134 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
136 let { this_pkg = thisPackage (hsc_dflags hsc_env) ;
137 this_mod = case maybe_mod of
138 Nothing -> mAIN -- 'module M where' is omitted
139 Just (L _ mod) -> mkModule this_pkg mod } ;
142 initTc hsc_env hsc_src save_rn_syntax this_mod $
144 do { -- Deal with imports;
145 tcg_env <- tcRnImports hsc_env this_mod import_decls ;
146 setGblEnv tcg_env $ do {
148 -- Load the hi-boot interface for this module, if any
149 -- We do this now so that the boot_names can be passed
150 -- to tcTyAndClassDecls, because the boot_names are
151 -- automatically considered to be loop breakers
153 -- Do this *after* tcRnImports, so that we know whether
154 -- a module that we import imports us; and hence whether to
155 -- look for a hi-boot file
156 boot_iface <- tcHiBootIface hsc_src this_mod ;
158 -- Rename and type check the declarations
159 traceRn (text "rn1a") ;
160 tcg_env <- if isHsBoot hsc_src then
161 tcRnHsBootDecls local_decls
163 tcRnSrcDecls boot_iface local_decls ;
164 setGblEnv tcg_env $ do {
166 -- Report the use of any deprecated things
167 -- We do this *before* processsing the export list so
168 -- that we don't bleat about re-exporting a deprecated
169 -- thing (especially via 'module Foo' export item)
170 -- That is, only uses in the *body* of the module are complained about
171 traceRn (text "rn3") ;
172 failIfErrsM ; -- finishWarnings crashes sometimes
173 -- as a result of typechecker repairs (e.g. unboundNames)
174 tcg_env <- finishWarnings (hsc_dflags hsc_env) mod_deprec tcg_env ;
176 -- Process the export list
177 traceRn (text "rn4a: before exports");
178 tcg_env <- rnExports (isJust maybe_mod) export_ies tcg_env ;
179 traceRn (text "rn4b: after exportss") ;
181 -- Compare the hi-boot iface (if any) with the real thing
182 -- Must be done after processing the exports
183 tcg_env <- checkHiBootIface tcg_env boot_iface ;
185 -- The new type env is already available to stuff slurped from
186 -- interface files, via TcEnv.updateGlobalTypeEnv
187 -- It's important that this includes the stuff in checkHiBootIface,
188 -- because the latter might add new bindings for boot_dfuns,
189 -- which may be mentioned in imported unfoldings
191 -- Rename the Haddock documentation
192 tcg_env <- rnHaddock module_info maybe_doc tcg_env ;
194 -- Report unused names
195 reportUnusedNames export_ies tcg_env ;
197 -- Dump output and return
204 %************************************************************************
208 %************************************************************************
211 tcRnImports :: HscEnv -> Module -> [LImportDecl RdrName] -> TcM TcGblEnv
212 tcRnImports hsc_env this_mod import_decls
213 = do { (rn_imports, rdr_env, imports,hpc_info) <- rnImports import_decls ;
215 ; let { dep_mods :: ModuleNameEnv (ModuleName, IsBootInterface)
216 ; dep_mods = imp_dep_mods imports
218 -- We want instance declarations from all home-package
219 -- modules below this one, including boot modules, except
220 -- ourselves. The 'except ourselves' is so that we don't
221 -- get the instances from this module's hs-boot file
222 ; want_instances :: ModuleName -> Bool
223 ; want_instances mod = mod `elemUFM` dep_mods
224 && mod /= moduleName this_mod
225 ; (home_insts, home_fam_insts) = hptInstances hsc_env
229 -- Record boot-file info in the EPS, so that it's
230 -- visible to loadHiBootInterface in tcRnSrcDecls,
231 -- and any other incrementally-performed imports
232 ; updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
234 -- Update the gbl env
235 ; updGblEnv ( \ gbl ->
237 tcg_rdr_env = plusOccEnv (tcg_rdr_env gbl) rdr_env,
238 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
239 tcg_rn_imports = fmap (const rn_imports) (tcg_rn_imports gbl),
240 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
241 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env gbl)
246 ; traceRn (text "rn1" <+> ppr (imp_dep_mods imports))
247 -- Fail if there are any errors so far
248 -- The error printing (if needed) takes advantage
249 -- of the tcg_env we have now set
250 -- ; traceIf (text "rdr_env: " <+> ppr rdr_env)
253 -- Load any orphan-module and family instance-module
254 -- interfaces, so that their rules and instance decls will be
256 ; loadOrphanModules (imp_orphs imports) False
257 ; loadOrphanModules (imp_finsts imports) True
259 -- Check type-familily consistency
260 ; traceRn (text "rn1: checking family instance consistency")
261 ; let { dir_imp_mods = moduleEnvKeys
264 ; checkFamInstConsistency (imp_finsts imports) dir_imp_mods ;
270 %************************************************************************
272 Type-checking external-core modules
274 %************************************************************************
277 tcRnExtCore :: HscEnv
279 -> IO (Messages, Maybe ModGuts)
280 -- Nothing => some error occurred
282 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
283 -- The decls are IfaceDecls; all names are original names
284 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
286 initTc hsc_env ExtCoreFile False this_mod $ do {
288 let { ldecls = map noLoc decls } ;
290 -- bring the type and class decls into scope
291 -- ToDo: check that this doesn't need to extract the val binds.
292 -- It seems that only the type and class decls need to be in scope below because
293 -- (a) tcTyAndClassDecls doesn't need the val binds, and
294 -- (b) tcExtCoreBindings doesn't need anything
295 -- (in fact, it might not even need to be in the scope of
296 -- this tcg_env at all)
297 avails <- getLocalNonValBinders (mkFakeGroup ldecls) ;
298 tc_envs <- extendGlobalRdrEnvRn avails emptyFsEnv {- no fixity decls -} ;
300 setEnvs tc_envs $ do {
302 rn_decls <- checkNoErrs $ rnTyClDecls ldecls ;
304 -- Dump trace of renaming part
305 rnDump (ppr rn_decls) ;
307 -- Typecheck them all together so that
308 -- any mutually recursive types are done right
309 tcg_env <- tcTyAndClassDecls emptyModDetails rn_decls ;
310 -- Make the new type env available to stuff slurped from interface files
312 setGblEnv tcg_env $ do {
314 -- Now the core bindings
315 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
319 bndrs = bindersOfBinds core_binds ;
320 my_exports = map (Avail . idName) bndrs ;
321 -- ToDo: export the data types also?
324 extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
326 mod_guts = ModGuts { mg_module = this_mod,
328 mg_used_names = emptyNameSet, -- ToDo: compute usage
329 mg_dir_imps = emptyModuleEnv, -- ??
330 mg_deps = noDependencies, -- ??
331 mg_exports = my_exports,
332 mg_types = final_type_env,
333 mg_insts = tcg_insts tcg_env,
334 mg_fam_insts = tcg_fam_insts tcg_env,
335 mg_inst_env = tcg_inst_env tcg_env,
336 mg_fam_inst_env = tcg_fam_inst_env tcg_env,
338 mg_binds = core_binds,
341 mg_rdr_env = emptyGlobalRdrEnv,
342 mg_fix_env = emptyFixityEnv,
343 mg_warns = NoWarnings,
344 mg_foreign = NoStubs,
345 mg_hpc_info = emptyHpcInfo False,
346 mg_modBreaks = emptyModBreaks,
347 mg_vect_info = noVectInfo
350 tcCoreDump mod_guts ;
355 mkFakeGroup decls -- Rather clumsy; lots of unused fields
356 = emptyRdrGroup { hs_tyclds = decls }
360 %************************************************************************
362 Type-checking the top level of a module
364 %************************************************************************
367 tcRnSrcDecls :: ModDetails -> [LHsDecl RdrName] -> TcM TcGblEnv
368 -- Returns the variables free in the decls
369 -- Reason: solely to report unused imports and bindings
370 tcRnSrcDecls boot_iface decls
371 = do { -- Do all the declarations
372 (tc_envs, lie) <- getLIE $ tc_rn_src_decls boot_iface decls ;
374 -- Finish simplifying class constraints
376 -- tcSimplifyTop 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 tcSimplifyTop
386 -- * the local env exposes the local Ids to tcSimplifyTop,
387 -- so that we get better error messages (monomorphism restriction)
388 traceTc (text "Tc8") ;
389 inst_binds <- setEnvs tc_envs (tcSimplifyTop lie) ;
391 -- Backsubstitution. This must be done last.
392 -- Even tcSimplifyTop may do some unification.
393 traceTc (text "Tc9") ;
394 let { (tcg_env, _) = tc_envs
395 ; TcGblEnv { tcg_type_env = type_env,
398 tcg_fords = fords } = tcg_env
399 ; all_binds = binds `unionBags` inst_binds } ;
401 failIfErrsM ; -- Don't zonk if there have been errors
402 -- It's a waste of time; and we may get debug warnings
403 -- about strangely-typed TyCons!
405 (bind_ids, binds', fords', rules') <- zonkTopDecls all_binds rules fords ;
408 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
409 ; tcg_env' = tcg_env { tcg_binds = binds',
411 tcg_fords = fords' } } ;
413 setGlobalTypeEnv tcg_env' final_type_env
416 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
417 -- Loops around dealing with each top level inter-splice group
418 -- in turn, until it's dealt with the entire module
419 tc_rn_src_decls boot_details ds
420 = do { let { (first_group, group_tail) = findSplice ds } ;
421 -- If ds is [] we get ([], Nothing)
423 -- Deal with decls up to, but not including, the first splice
424 (tcg_env, rn_decls) <- rnTopSrcDecls first_group ;
425 -- rnTopSrcDecls fails if there are any errors
427 (tcg_env, tcl_env) <- setGblEnv tcg_env $
428 tcTopSrcDecls boot_details rn_decls ;
430 -- If there is no splice, we're nearly done
431 setEnvs (tcg_env, tcl_env) $
433 Nothing -> do { tcg_env <- checkMain ; -- Check for `main'
434 return (tcg_env, tcl_env)
437 -- If there's a splice, we must carry on
438 Just (SpliceDecl splice_expr, rest_ds) -> do {
440 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
443 -- Rename the splice expression, and get its supporting decls
444 (rn_splice_expr, splice_fvs) <- checkNoErrs (rnLExpr splice_expr) ;
445 -- checkNoErrs: don't typecheck if renaming failed
446 rnDump (ppr rn_splice_expr) ;
448 -- Execute the splice
449 spliced_decls <- tcSpliceDecls rn_splice_expr ;
451 -- Glue them on the front of the remaining decls and loop
452 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
453 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
458 %************************************************************************
460 Compiling hs-boot source files, and
461 comparing the hi-boot interface with the real thing
463 %************************************************************************
466 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
467 tcRnHsBootDecls decls
468 = do { let { (first_group, group_tail) = findSplice decls }
471 Just stuff -> spliceInHsBootErr stuff
474 -- Rename the declarations
475 ; (tcg_env, HsGroup {
476 hs_tyclds = tycl_decls,
477 hs_instds = inst_decls,
478 hs_derivds = deriv_decls,
480 hs_defds = _, -- Todo: check no foreign decls, no rules,
481 hs_ruleds = _, -- no default decls and no annotation decls
483 hs_valds = val_binds }) <- rnTopSrcDecls first_group
484 ; setGblEnv tcg_env $ do {
487 -- Typecheck type/class decls
488 ; traceTc (text "Tc2")
489 ; tcg_env <- tcTyAndClassDecls emptyModDetails tycl_decls
490 ; setGblEnv tcg_env $ do {
492 -- Typecheck instance decls
493 ; traceTc (text "Tc3")
494 ; (tcg_env, inst_infos, _deriv_binds)
495 <- tcInstDecls1 tycl_decls inst_decls deriv_decls
496 ; setGblEnv tcg_env $ do {
498 -- Typecheck value declarations
499 ; traceTc (text "Tc5")
500 ; val_ids <- tcHsBootSigs val_binds
503 -- No simplification or zonking to do
504 ; traceTc (text "Tc7a")
505 ; gbl_env <- getGblEnv
507 -- Make the final type-env
508 -- Include the dfun_ids so that their type sigs
509 -- are written into the interface file
510 ; let { type_env0 = tcg_type_env gbl_env
511 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
512 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
513 ; dfun_ids = map iDFunId inst_infos }
514 ; setGlobalTypeEnv gbl_env type_env2
517 spliceInHsBootErr (SpliceDecl (L loc _), _)
518 = addErrAt loc (ptext (sLit "Splices are not allowed in hs-boot files"))
521 Once we've typechecked the body of the module, we want to compare what
522 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
525 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM TcGblEnv
526 -- Compare the hi-boot file for this module (if there is one)
527 -- with the type environment we've just come up with
528 -- In the common case where there is no hi-boot file, the list
529 -- of boot_names is empty.
531 -- The bindings we return give bindings for the dfuns defined in the
532 -- hs-boot file, such as $fbEqT = $fEqT
535 tcg_env@(TcGblEnv { tcg_src = hs_src, tcg_binds = binds,
536 tcg_insts = local_insts, tcg_fam_insts = local_fam_insts,
537 tcg_type_env = local_type_env, tcg_exports = local_exports })
538 (ModDetails { md_insts = boot_insts, md_fam_insts = boot_fam_insts,
539 md_types = boot_type_env, md_exports = boot_exports })
540 | isHsBoot hs_src -- Current module is already a hs-boot file!
544 = do { traceTc (text "checkHiBootIface" <+> (ppr boot_type_env $$ ppr boot_insts $$
547 -- Check the exports of the boot module, one by one
548 ; mapM_ check_export boot_exports
550 -- Check for no family instances
551 ; unless (null boot_fam_insts) $
552 panic ("TcRnDriver.checkHiBootIface: Cannot handle family " ++
553 "instances in boot files yet...")
554 -- FIXME: Why? The actual comparison is not hard, but what would
555 -- be the equivalent to the dfun bindings returned for class
556 -- instances? We can't easily equate tycons...
558 -- Check instance declarations
559 ; mb_dfun_prs <- mapM check_inst boot_insts
560 ; let tcg_env' = tcg_env { tcg_binds = binds `unionBags` dfun_binds }
561 final_type_env = extendTypeEnvWithIds local_type_env boot_dfuns
562 dfun_prs = catMaybes mb_dfun_prs
563 boot_dfuns = map fst dfun_prs
564 dfun_binds = listToBag [ noLoc $ VarBind boot_dfun (nlHsVar dfun)
565 | (boot_dfun, dfun) <- dfun_prs ]
568 ; setGlobalTypeEnv tcg_env' final_type_env }
570 check_export boot_avail -- boot_avail is exported by the boot iface
571 | name `elem` dfun_names = return ()
572 | isWiredInName name = return () -- No checking for wired-in names. In particular,
573 -- 'error' is handled by a rather gross hack
574 -- (see comments in GHC.Err.hs-boot)
576 -- Check that the actual module exports the same thing
577 | not (null missing_names)
578 = addErrAt (nameSrcSpan (head missing_names))
579 (missingBootThing (head missing_names) "exported by")
581 -- If the boot module does not *define* the thing, we are done
582 -- (it simply re-exports it, and names match, so nothing further to do)
583 | isNothing mb_boot_thing = return ()
585 -- Check that the actual module also defines the thing, and
586 -- then compare the definitions
587 | Just real_thing <- lookupTypeEnv local_type_env name,
588 Just boot_thing <- mb_boot_thing
589 = when (not (checkBootDecl boot_thing real_thing))
590 $ addErrAt (nameSrcSpan (getName boot_thing))
591 (let boot_decl = tyThingToIfaceDecl
592 (fromJust mb_boot_thing)
593 real_decl = tyThingToIfaceDecl real_thing
594 in bootMisMatch real_thing boot_decl real_decl)
597 = addErrTc (missingBootThing name "defined in")
599 name = availName boot_avail
600 mb_boot_thing = lookupTypeEnv boot_type_env name
601 missing_names = case lookupNameEnv local_export_env name of
603 Just avail -> availNames boot_avail `minusList` availNames avail
605 dfun_names = map getName boot_insts
607 local_export_env :: NameEnv AvailInfo
608 local_export_env = availsToNameEnv local_exports
610 check_inst :: Instance -> TcM (Maybe (Id, Id))
611 -- Returns a pair of the boot dfun in terms of the equivalent real dfun
613 = case [dfun | inst <- local_insts,
614 let dfun = instanceDFunId inst,
615 idType dfun `tcEqType` boot_inst_ty ] of
616 [] -> do { addErrTc (instMisMatch boot_inst); return Nothing }
617 (dfun:_) -> return (Just (local_boot_dfun, dfun))
619 boot_dfun = instanceDFunId boot_inst
620 boot_inst_ty = idType boot_dfun
621 local_boot_dfun = Id.mkExportedLocalId (idName boot_dfun) boot_inst_ty
624 -- This has to compare the TyThing from the .hi-boot file to the TyThing
625 -- in the current source file. We must be careful to allow alpha-renaming
626 -- where appropriate, and also the boot declaration is allowed to omit
627 -- constructors and class methods.
629 -- See rnfail055 for a good test of this stuff.
631 checkBootDecl :: TyThing -> TyThing -> Bool
633 checkBootDecl (AnId id1) (AnId id2)
635 (idType id1 `tcEqType` idType id2)
637 checkBootDecl (ATyCon tc1) (ATyCon tc2)
638 | isSynTyCon tc1 && isSynTyCon tc2
640 let tvs1 = tyConTyVars tc1; tvs2 = tyConTyVars tc2
641 env = rnBndrs2 env0 tvs1 tvs2
643 eqSynRhs (OpenSynTyCon k1 _) (OpenSynTyCon k2 _)
644 = tcEqTypeX env k1 k2
645 eqSynRhs (SynonymTyCon t1) (SynonymTyCon t2)
646 = tcEqTypeX env t1 t2
648 equalLength tvs1 tvs2 &&
649 eqSynRhs (synTyConRhs tc1) (synTyConRhs tc2)
651 | isAlgTyCon tc1 && isAlgTyCon tc2
653 eqListBy tcEqPred (tyConStupidTheta tc1) (tyConStupidTheta tc2)
654 && eqAlgRhs (algTyConRhs tc1) (algTyConRhs tc2)
656 | isForeignTyCon tc1 && isForeignTyCon tc2
657 = tyConExtName tc1 == tyConExtName tc2
659 env0 = mkRnEnv2 emptyInScopeSet
661 eqAlgRhs AbstractTyCon _ = True
662 eqAlgRhs OpenTyCon{} OpenTyCon{} = True
663 eqAlgRhs tc1@DataTyCon{} tc2@DataTyCon{} =
664 eqListBy eqCon (data_cons tc1) (data_cons tc2)
665 eqAlgRhs tc1@NewTyCon{} tc2@NewTyCon{} =
666 eqCon (data_con tc1) (data_con tc2)
670 = dataConName c1 == dataConName c2
671 && dataConIsInfix c1 == dataConIsInfix c2
672 && dataConStrictMarks c1 == dataConStrictMarks c2
673 && dataConFieldLabels c1 == dataConFieldLabels c2
674 && let tvs1 = dataConUnivTyVars c1 ++ dataConExTyVars c1
675 tvs2 = dataConUnivTyVars c2 ++ dataConExTyVars c2
676 env = rnBndrs2 env0 tvs1 tvs2
678 equalLength tvs1 tvs2 &&
679 eqListBy (tcEqPredX env)
680 (dataConEqTheta c1 ++ dataConDictTheta c1)
681 (dataConEqTheta c2 ++ dataConDictTheta c2) &&
682 eqListBy (tcEqTypeX env)
683 (dataConOrigArgTys c1)
684 (dataConOrigArgTys c2)
686 checkBootDecl (AClass c1) (AClass c2)
688 (clas_tyvars1, clas_fds1, sc_theta1, _, _, op_stuff1)
689 = classExtraBigSig c1
690 (clas_tyvars2, clas_fds2, sc_theta2, _, _, op_stuff2)
691 = classExtraBigSig c2
693 env0 = mkRnEnv2 emptyInScopeSet
694 env = rnBndrs2 env0 clas_tyvars1 clas_tyvars2
696 eqSig (id1, def_meth1) (id2, def_meth2)
697 = idName id1 == idName id2 &&
698 tcEqTypeX env op_ty1 op_ty2
700 (_, rho_ty1) = splitForAllTys (idType id1)
701 op_ty1 = funResultTy rho_ty1
702 (_, rho_ty2) = splitForAllTys (idType id2)
703 op_ty2 = funResultTy rho_ty2
705 eqFD (as1,bs1) (as2,bs2) =
706 eqListBy (tcEqTypeX env) (mkTyVarTys as1) (mkTyVarTys as2) &&
707 eqListBy (tcEqTypeX env) (mkTyVarTys bs1) (mkTyVarTys bs2)
709 equalLength clas_tyvars1 clas_tyvars2 &&
710 eqListBy eqFD clas_fds1 clas_fds2 &&
711 (null sc_theta1 && null op_stuff1
713 eqListBy (tcEqPredX env) sc_theta1 sc_theta2 &&
714 eqListBy eqSig op_stuff1 op_stuff2)
716 checkBootDecl (ADataCon dc1) (ADataCon dc2)
717 = pprPanic "checkBootDecl" (ppr dc1)
719 checkBootDecl _ _ = False -- probably shouldn't happen
722 missingBootThing thing what
723 = ppr thing <+> ptext (sLit "is exported by the hs-boot file, but not")
724 <+> text what <+> ptext (sLit "the module")
726 bootMisMatch thing boot_decl real_decl
727 = vcat [ppr thing <+> ptext (sLit "has conflicting definitions in the module and its hs-boot file"),
728 ptext (sLit "Main module:") <+> ppr real_decl,
729 ptext (sLit "Boot file: ") <+> ppr boot_decl]
733 2 (ptext (sLit "is defined in the hs-boot file, but not in the module itself"))
737 %************************************************************************
739 Type-checking the top level of a module
741 %************************************************************************
743 tcRnGroup takes a bunch of top-level source-code declarations, and
745 * gets supporting declarations from interface files
748 * and augments the TcGblEnv with the results
750 In Template Haskell it may be called repeatedly for each group of
751 declarations. It expects there to be an incoming TcGblEnv in the
752 monad; it augments it and returns the new TcGblEnv.
755 ------------------------------------------------
756 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
757 -- Fails if there are any errors
759 = do { -- Rename the source decls
760 (tcg_env, rn_decls) <- checkNoErrs $ rnSrcDecls group ;
762 -- save the renamed syntax, if we want it
764 | Just grp <- tcg_rn_decls tcg_env
765 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
769 -- Dump trace of renaming part
770 rnDump (ppr rn_decls) ;
772 return (tcg_env', rn_decls)
775 ------------------------------------------------
776 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
777 tcTopSrcDecls boot_details
778 (HsGroup { hs_tyclds = tycl_decls,
779 hs_instds = inst_decls,
780 hs_derivds = deriv_decls,
781 hs_fords = foreign_decls,
782 hs_defds = default_decls,
783 hs_annds = annotation_decls,
784 hs_ruleds = rule_decls,
785 hs_valds = val_binds })
786 = do { -- Type-check the type and class decls, and all imported decls
787 -- The latter come in via tycl_decls
788 traceTc (text "Tc2") ;
790 tcg_env <- tcTyAndClassDecls boot_details tycl_decls ;
791 -- If there are any errors, tcTyAndClassDecls fails here
793 setGblEnv tcg_env $ do {
794 -- Source-language instances, including derivings,
795 -- and import the supporting declarations
796 traceTc (text "Tc3") ;
797 (tcg_env, inst_infos, deriv_binds)
798 <- tcInstDecls1 tycl_decls inst_decls deriv_decls;
799 setGblEnv tcg_env $ do {
801 -- Foreign import declarations next. No zonking necessary
802 -- here; we can tuck them straight into the global environment.
803 traceTc (text "Tc4") ;
804 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
805 tcExtendGlobalValEnv fi_ids $ do {
807 -- Default declarations
808 traceTc (text "Tc4a") ;
809 default_tys <- tcDefaults default_decls ;
810 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
812 -- Value declarations next
813 -- We also typecheck any extra binds that came out
814 -- of the "deriving" process (deriv_binds)
815 traceTc (text "Tc5") ;
816 (tc_val_binds, tcl_env) <- tcTopBinds val_binds ;
817 setLclTypeEnv tcl_env $ do {
819 -- Now GHC-generated derived bindings and generics.
820 -- Do not generate warnings from compiler-generated code.
821 (tc_deriv_binds, tcl_env) <- discardWarnings $
822 tcTopBinds deriv_binds ;
824 -- Second pass over class and instance declarations,
825 traceTc (text "Tc6") ;
826 (inst_binds, tcl_env) <- setLclTypeEnv tcl_env $ tcInstDecls2 tycl_decls inst_infos ;
827 showLIE (text "after instDecls2") ;
830 -- They need to be zonked, so we return them
831 traceTc (text "Tc7") ;
832 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
835 annotations <- tcAnnotations annotation_decls ;
838 rules <- tcRules rule_decls ;
841 traceTc (text "Tc7a") ;
842 tcg_env <- getGblEnv ;
843 let { all_binds = tc_val_binds `unionBags`
844 tc_deriv_binds `unionBags`
845 inst_binds `unionBags`
848 -- Extend the GblEnv with the (as yet un-zonked)
849 -- bindings, rules, foreign decls
850 tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds,
851 tcg_rules = tcg_rules tcg_env ++ rules,
852 tcg_anns = tcg_anns tcg_env ++ annotations,
853 tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
854 return (tcg_env', tcl_env)
859 %************************************************************************
863 %************************************************************************
866 checkMain :: TcM TcGblEnv
867 -- If we are in module Main, check that 'main' is defined.
869 = do { tcg_env <- getGblEnv ;
871 check_main dflags tcg_env
874 check_main dflags tcg_env
876 = traceTc (text "checkMain not" <+> ppr main_mod <+> ppr mod) >>
880 = do { mb_main <- lookupSrcOcc_maybe main_fn
881 -- Check that 'main' is in scope
882 -- It might be imported from another module!
884 Nothing -> do { traceTc (text "checkMain fail" <+> ppr main_mod <+> ppr main_fn)
889 { traceTc (text "checkMain found" <+> ppr main_mod <+> ppr main_fn)
890 ; let loc = srcLocSpan (getSrcLoc main_name)
891 ; ioTyCon <- tcLookupTyCon ioTyConName
892 ; (main_expr, res_ty)
893 <- addErrCtxt mainCtxt $
894 withBox liftedTypeKind $ \res_ty ->
895 tcMonoExpr (L loc (HsVar main_name)) (mkTyConApp ioTyCon [res_ty])
897 -- See Note [Root-main Id]
898 -- Construct the binding
899 -- :Main.main :: IO res_ty = runMainIO res_ty main
900 ; run_main_id <- tcLookupId runMainIOName
901 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
902 (mkVarOccFS (fsLit "main"))
903 (getSrcSpan main_name)
904 ; root_main_id = Id.mkExportedLocalId root_main_name
905 (mkTyConApp ioTyCon [res_ty])
906 ; co = mkWpTyApps [res_ty]
907 ; rhs = nlHsApp (mkLHsWrap co (nlHsVar run_main_id)) main_expr
908 ; main_bind = noLoc (VarBind root_main_id rhs) }
910 ; return (tcg_env { tcg_binds = tcg_binds tcg_env
912 tcg_dus = tcg_dus tcg_env
913 `plusDU` usesOnly (unitFV main_name)
914 -- Record the use of 'main', so that we don't
915 -- complain about it being defined but not used
919 mod = tcg_mod tcg_env
920 main_mod = mainModIs dflags
921 main_fn = getMainFun dflags
923 complain_no_main | ghcLink dflags == LinkInMemory = return ()
924 | otherwise = failWithTc noMainMsg
925 -- In interactive mode, don't worry about the absence of 'main'
926 -- In other modes, fail altogether, so that we don't go on
927 -- and complain a second time when processing the export list.
929 mainCtxt = ptext (sLit "When checking the type of the") <+> pp_main_fn
930 noMainMsg = ptext (sLit "The") <+> pp_main_fn
931 <+> ptext (sLit "is not defined in module") <+> quotes (ppr main_mod)
932 pp_main_fn | main_fn == main_RDR_Unqual = ptext (sLit "function") <+> quotes (ppr main_fn)
933 | otherwise = ptext (sLit "main function") <+> quotes (ppr main_fn)
939 The function that the RTS invokes is always :Main.main, which we call
940 root_main_id. (Because GHC allows the user to have a module not
941 called Main as the main module, we can't rely on the main function
942 being called "Main.main". That's why root_main_id has a fixed module
945 This is unusual: it's a LocalId whose Name has a Module from another
946 module. Tiresomely, we must filter it out again in MkIface, les we
947 get two defns for 'main' in the interface file!
950 %*********************************************************
954 %*********************************************************
958 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
959 setInteractiveContext hsc_env icxt thing_inside
960 = let -- Initialise the tcg_inst_env with instances from all home modules.
961 -- This mimics the more selective call to hptInstances in tcRnModule.
962 (home_insts, home_fam_insts) = hptInstances hsc_env (\mod -> True)
964 updGblEnv (\env -> env {
965 tcg_rdr_env = ic_rn_gbl_env icxt,
966 tcg_inst_env = extendInstEnvList (tcg_inst_env env) home_insts,
967 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env env)
971 tcExtendGhciEnv (ic_tmp_ids icxt) $
972 -- tcExtendGhciEnv does lots:
973 -- - it extends the local type env (tcl_env) with the given Ids,
974 -- - it extends the local rdr env (tcl_rdr) with the Names from
976 -- - it adds the free tyvars of the Ids to the tcl_tyvars
979 -- later ids in ic_tmp_ids must shadow earlier ones with the same
980 -- OccName, and tcExtendIdEnv implements this behaviour.
982 do { traceTc (text "setIC" <+> ppr (ic_tmp_ids icxt))
989 -> InteractiveContext
991 -> IO (Messages, Maybe ([Id], LHsExpr Id))
992 -- The returned [Id] is the list of new Ids bound by
993 -- this statement. It can be used to extend the
994 -- InteractiveContext via extendInteractiveContext.
996 -- The returned TypecheckedHsExpr is of type IO [ () ],
997 -- a list of the bound values, coerced to ().
999 tcRnStmt hsc_env ictxt rdr_stmt
1000 = initTcPrintErrors hsc_env iNTERACTIVE $
1001 setInteractiveContext hsc_env ictxt $ do {
1003 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
1004 (([rn_stmt], _), fvs) <- rnStmts DoExpr [rdr_stmt] (return ((), emptyFVs)) ;
1005 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
1007 rnDump (ppr rn_stmt) ;
1009 -- The real work is done here
1010 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
1011 zonked_expr <- zonkTopLExpr tc_expr ;
1012 zonked_ids <- zonkTopBndrs bound_ids ;
1014 -- None of the Ids should be of unboxed type, because we
1015 -- cast them all to HValues in the end!
1016 mapM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
1018 traceTc (text "tcs 1") ;
1019 let { global_ids = map globaliseAndTidy zonked_ids } ;
1021 {- ---------------------------------------------
1022 At one stage I removed any shadowed bindings from the type_env;
1023 they are inaccessible but might, I suppose, cause a space leak if we leave them there.
1024 However, with Template Haskell they aren't necessarily inaccessible. Consider this
1026 Prelude> let f n = n * 2 :: Int
1027 Prelude> fName <- runQ [| f |]
1028 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1030 Prelude> let f n = n * 3 :: Int
1031 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
1032 In the last line we use 'fName', which resolves to the *first* 'f'
1033 in scope. If we delete it from the type env, GHCi crashes because
1034 it doesn't expect that.
1036 Hence this code is commented out
1038 -------------------------------------------------- -}
1040 dumpOptTcRn Opt_D_dump_tc
1041 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
1042 text "Typechecked expr" <+> ppr zonked_expr]) ;
1044 return (global_ids, zonked_expr)
1047 bad_unboxed id = addErr (sep [ptext (sLit "GHCi can't bind a variable of unlifted type:"),
1048 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
1050 globaliseAndTidy :: Id -> Id
1051 globaliseAndTidy id -- Note [Interactively-bound Ids in GHCi]
1052 = Id.setIdType (globaliseId VanillaGlobal id) tidy_type
1054 tidy_type = tidyTopType (idType id)
1057 Note [Interactively-bound Ids in GHCi]
1058 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1059 The Ids bound by previous Stmts in Template Haskell are currently
1061 b) with an Internal Name (not External)
1062 c) and a tidied type
1064 (a) They must be GlobalIds (not LocalIds) otherwise when we come to
1065 compile an expression using these ids later, the byte code
1066 generator will consider the occurrences to be free rather than
1069 (b) They retain their Internal names becuase we don't have a suitable
1070 Module to name them with. We could revisit this choice.
1072 (c) Their types are tidied. This is important, because :info may ask
1073 to look at them, and :info expects the things it looks up to have
1077 --------------------------------------------------------------------------
1078 Typechecking Stmts in GHCi
1080 Here is the grand plan, implemented in tcUserStmt
1082 What you type The IO [HValue] that hscStmt returns
1083 ------------- ------------------------------------
1084 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
1087 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
1090 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
1091 [NB: result not printed] bindings: [it]
1093 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
1094 result showable) bindings: [it]
1096 expr (of non-IO type,
1097 result not showable) ==> error
1101 ---------------------------
1102 type PlanResult = ([Id], LHsExpr Id)
1103 type Plan = TcM PlanResult
1105 runPlans :: [Plan] -> TcM PlanResult
1106 -- Try the plans in order. If one fails (by raising an exn), try the next.
1107 -- If one succeeds, take it.
1108 runPlans [] = panic "runPlans"
1110 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
1112 --------------------
1113 mkPlan :: LStmt Name -> TcM PlanResult
1114 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
1115 = do { uniq <- newUnique -- is treated very specially
1116 ; let fresh_it = itName uniq
1117 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
1118 matches = [mkMatch [] expr emptyLocalBinds]
1119 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
1120 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
1121 (HsVar bindIOName) noSyntaxExpr
1122 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
1123 (HsVar thenIOName) placeHolderType
1126 -- [it <- e; print it] but not if it::()
1128 -- [let it = e; print it]
1129 ; runPlans [ -- Plan A
1130 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
1131 ; it_ty <- zonkTcType (idType it_id)
1132 ; when (isUnitTy it_ty) failM
1135 -- Plan B; a naked bind statment
1136 tcGhciStmts [bind_stmt],
1138 -- Plan C; check that the let-binding is typeable all by itself.
1139 -- If not, fail; if so, try to print it.
1140 -- The two-step process avoids getting two errors: one from
1141 -- the expression itself, and one from the 'print it' part
1142 -- This two-step story is very clunky, alas
1143 do { checkNoErrs (tcGhciStmts [let_stmt])
1144 --- checkNoErrs defeats the error recovery of let-bindings
1145 ; tcGhciStmts [let_stmt, print_it] }
1148 mkPlan stmt@(L loc (BindStmt {}))
1149 | [L _ v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
1150 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
1151 (HsVar thenIOName) placeHolderType
1153 ; print_bind_result <- doptM Opt_PrintBindResult
1154 ; let print_plan = do
1155 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
1156 ; v_ty <- zonkTcType (idType v_id)
1157 ; when (isUnitTy v_ty || not (isTauTy v_ty)) failM
1161 -- [stmt; print v] but not if v::()
1163 ; runPlans ((if print_bind_result then [print_plan] else []) ++
1164 [tcGhciStmts [stmt]])
1168 = tcGhciStmts [stmt]
1170 ---------------------------
1171 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1173 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1174 ret_id <- tcLookupId returnIOName ; -- return @ IO
1176 ret_ty = mkListTy unitTy ;
1177 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1178 tc_io_stmts stmts = tcStmts DoExpr tcDoStmt stmts io_ret_ty ;
1180 names = map unLoc (collectLStmtsBinders stmts) ;
1182 -- mk_return builds the expression
1183 -- returnIO @ [()] [coerce () x, .., coerce () z]
1185 -- Despite the inconvenience of building the type applications etc,
1186 -- this *has* to be done in type-annotated post-typecheck form
1187 -- because we are going to return a list of *polymorphic* values
1188 -- coerced to type (). If we built a *source* stmt
1189 -- return [coerce x, ..., coerce z]
1190 -- then the type checker would instantiate x..z, and we wouldn't
1191 -- get their *polymorphic* values. (And we'd get ambiguity errs
1192 -- if they were overloaded, since they aren't applied to anything.)
1193 mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty])
1194 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1195 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1199 -- OK, we're ready to typecheck the stmts
1200 traceTc (text "TcRnDriver.tcGhciStmts: tc stmts") ;
1201 ((tc_stmts, ids), lie) <- getLIE $ tc_io_stmts stmts $ \ _ ->
1202 mapM tcLookupId names ;
1203 -- Look up the names right in the middle,
1204 -- where they will all be in scope
1206 -- Simplify the context
1207 traceTc (text "TcRnDriver.tcGhciStmts: simplify ctxt") ;
1208 const_binds <- checkNoErrs (tcSimplifyInteractive lie) ;
1209 -- checkNoErrs ensures that the plan fails if context redn fails
1211 traceTc (text "TcRnDriver.tcGhciStmts: done") ;
1212 return (ids, mkHsDictLet const_binds $
1213 noLoc (HsDo DoExpr tc_stmts (mk_return ids) io_ret_ty))
1218 tcRnExpr just finds the type of an expression
1222 -> InteractiveContext
1224 -> IO (Messages, Maybe Type)
1225 tcRnExpr hsc_env ictxt rdr_expr
1226 = initTcPrintErrors hsc_env iNTERACTIVE $
1227 setInteractiveContext hsc_env ictxt $ do {
1229 (rn_expr, fvs) <- rnLExpr rdr_expr ;
1232 -- Now typecheck the expression;
1233 -- it might have a rank-2 type (e.g. :t runST)
1234 ((tc_expr, res_ty), lie) <- getLIE (tcInferRho rn_expr) ;
1235 ((qtvs, dict_insts, _), lie_top) <- getLIE (tcSimplifyInfer smpl_doc (tyVarsOfType res_ty) lie) ;
1236 tcSimplifyInteractive lie_top ;
1238 let { all_expr_ty = mkForAllTys qtvs $
1239 mkFunTys (map (idType . instToId) dict_insts) $
1241 zonkTcType all_expr_ty
1244 smpl_doc = ptext (sLit "main expression")
1247 tcRnType just finds the kind of a type
1251 -> InteractiveContext
1253 -> IO (Messages, Maybe Kind)
1254 tcRnType hsc_env ictxt rdr_type
1255 = initTcPrintErrors hsc_env iNTERACTIVE $
1256 setInteractiveContext hsc_env ictxt $ do {
1258 rn_type <- rnLHsType doc rdr_type ;
1261 -- Now kind-check the type
1262 (ty', kind) <- kcHsType rn_type ;
1266 doc = ptext (sLit "In GHCi input")
1272 %************************************************************************
1274 More GHCi stuff, to do with browsing and getting info
1276 %************************************************************************
1280 -- | ASSUMES that the module is either in the 'HomePackageTable' or is
1281 -- a package module with an interface on disk. If neither of these is
1282 -- true, then the result will be an error indicating the interface
1283 -- could not be found.
1284 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe [AvailInfo])
1285 getModuleExports hsc_env mod
1288 checkMods = ic_toplev_scope ic ++ ic_exports ic
1290 initTc hsc_env HsSrcFile False iNTERACTIVE (tcGetModuleExports mod checkMods)
1292 -- Get the export avail info and also load all orphan and family-instance
1293 -- modules. Finally, check that the family instances of all modules in the
1294 -- interactive context are consistent (these modules are in the second
1296 tcGetModuleExports :: Module -> [Module] -> TcM [AvailInfo]
1297 tcGetModuleExports mod directlyImpMods
1298 = do { let doc = ptext (sLit "context for compiling statements")
1299 ; iface <- initIfaceTcRn $ loadSysInterface doc mod
1301 -- Load any orphan-module and family instance-module
1302 -- interfaces, so their instances are visible.
1303 ; loadOrphanModules (dep_orphs (mi_deps iface)) False
1304 ; loadOrphanModules (dep_finsts (mi_deps iface)) True
1306 -- Check that the family instances of all directly loaded
1307 -- modules are consistent.
1308 ; checkFamInstConsistency (dep_finsts (mi_deps iface)) directlyImpMods
1310 ; ifaceExportNames (mi_exports iface)
1313 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Messages, Maybe [Name])
1314 tcRnLookupRdrName hsc_env rdr_name
1315 = initTcPrintErrors hsc_env iNTERACTIVE $
1316 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1317 lookup_rdr_name rdr_name
1319 lookup_rdr_name rdr_name = do {
1320 -- If the identifier is a constructor (begins with an
1321 -- upper-case letter), then we need to consider both
1322 -- constructor and type class identifiers.
1323 let { rdr_names = dataTcOccs rdr_name } ;
1325 -- results :: [Either Messages Name]
1326 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1328 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1329 -- The successful lookups will be (Just name)
1330 let { (warns_s, good_names) = unzip [ (msgs, name)
1331 | (msgs, Just name) <- results] ;
1332 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1334 -- Fail if nothing good happened, else add warnings
1335 if null good_names then
1336 -- No lookup succeeded, so
1337 -- pick the first error message and report it
1338 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1339 -- while the other is "X is not in scope",
1340 -- we definitely want the former; but we might pick the latter
1341 do { addMessages (head errs_s) ; failM }
1342 else -- Add deprecation warnings
1343 mapM_ addMessages warns_s ;
1348 tcRnLookupName :: HscEnv -> Name -> IO (Messages, Maybe TyThing)
1349 tcRnLookupName hsc_env name
1350 = initTcPrintErrors hsc_env iNTERACTIVE $
1351 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1352 tcRnLookupName' name
1354 -- To look up a name we have to look in the local environment (tcl_lcl)
1355 -- as well as the global environment, which is what tcLookup does.
1356 -- But we also want a TyThing, so we have to convert:
1358 tcRnLookupName' :: Name -> TcRn TyThing
1359 tcRnLookupName' name = do
1360 tcthing <- tcLookup name
1362 AGlobal thing -> return thing
1363 ATcId{tct_id=id} -> return (AnId id)
1364 _ -> panic "tcRnLookupName'"
1366 tcRnGetInfo :: HscEnv
1368 -> IO (Messages, Maybe (TyThing, Fixity, [Instance]))
1370 -- Used to implemnent :info in GHCi
1372 -- Look up a RdrName and return all the TyThings it might be
1373 -- A capitalised RdrName is given to us in the DataName namespace,
1374 -- but we want to treat it as *both* a data constructor
1375 -- *and* as a type or class constructor;
1376 -- hence the call to dataTcOccs, and we return up to two results
1377 tcRnGetInfo hsc_env name
1378 = initTcPrintErrors hsc_env iNTERACTIVE $
1379 let ictxt = hsc_IC hsc_env in
1380 setInteractiveContext hsc_env ictxt $ do
1382 -- Load the interface for all unqualified types and classes
1383 -- That way we will find all the instance declarations
1384 -- (Packages have not orphan modules, and we assume that
1385 -- in the home package all relevant modules are loaded.)
1386 loadUnqualIfaces ictxt
1388 thing <- tcRnLookupName' name
1389 fixity <- lookupFixityRn name
1390 ispecs <- lookupInsts thing
1391 return (thing, fixity, ispecs)
1393 lookupInsts :: TyThing -> TcM [Instance]
1394 lookupInsts (AClass cls)
1395 = do { inst_envs <- tcGetInstEnvs
1396 ; return (classInstances inst_envs cls) }
1398 lookupInsts (ATyCon tc)
1399 = do { eps <- getEps -- Load all instances for all classes that are
1400 -- in the type environment (which are all the ones
1401 -- we've seen in any interface file so far)
1402 ; (pkg_ie, home_ie) <- tcGetInstEnvs -- Search all
1404 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1405 , let dfun = instanceDFunId ispec
1408 relevant df = tc_name `elemNameSet` tyClsNamesOfDFunHead (idType df)
1409 tc_name = tyConName tc
1411 lookupInsts other = return []
1413 loadUnqualIfaces :: InteractiveContext -> TcM ()
1414 -- Load the home module for everything that is in scope unqualified
1415 -- This is so that we can accurately report the instances for
1417 loadUnqualIfaces ictxt
1419 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1421 unqual_mods = [ nameModule name
1422 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1423 let name = gre_name gre,
1424 not (isInternalName name),
1425 isTcOcc (nameOccName name), -- Types and classes only
1426 unQualOK gre ] -- In scope unqualified
1427 doc = ptext (sLit "Need interface for module whose export(s) are in scope unqualified")
1431 %************************************************************************
1435 %************************************************************************
1438 rnDump :: SDoc -> TcRn ()
1439 -- Dump, with a banner, if -ddump-rn
1440 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1442 tcDump :: TcGblEnv -> TcRn ()
1444 = do { dflags <- getDOpts ;
1446 -- Dump short output if -ddump-types or -ddump-tc
1447 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1448 (dumpTcRn short_dump) ;
1450 -- Dump bindings if -ddump-tc
1451 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1454 short_dump = pprTcGblEnv env
1455 full_dump = pprLHsBinds (tcg_binds env)
1456 -- NB: foreign x-d's have undefined's in their types;
1457 -- hence can't show the tc_fords
1460 = do { dflags <- getDOpts ;
1461 when (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1462 (dumpTcRn (pprModGuts mod_guts)) ;
1464 -- Dump bindings if -ddump-tc
1465 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1467 full_dump = pprCoreBindings (mg_binds mod_guts)
1469 -- It's unpleasant having both pprModGuts and pprModDetails here
1470 pprTcGblEnv :: TcGblEnv -> SDoc
1471 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1473 tcg_fam_insts = fam_insts,
1475 tcg_imports = imports })
1476 = vcat [ ppr_types insts type_env
1477 , ppr_tycons fam_insts type_env
1479 , ppr_fam_insts fam_insts
1480 , vcat (map ppr rules)
1481 , ppr_gen_tycons (typeEnvTyCons type_env)
1482 , ptext (sLit "Dependent modules:") <+>
1483 ppr (sortBy cmp_mp $ eltsUFM (imp_dep_mods imports))
1484 , ptext (sLit "Dependent packages:") <+>
1485 ppr (sortBy stablePackageIdCmp $ imp_dep_pkgs imports)]
1486 where -- The two uses of sortBy are just to reduce unnecessary
1487 -- wobbling in testsuite output
1488 cmp_mp (mod_name1, is_boot1) (mod_name2, is_boot2)
1489 = (mod_name1 `stableModuleNameCmp` mod_name2)
1491 (is_boot1 `compare` is_boot2)
1493 pprModGuts :: ModGuts -> SDoc
1494 pprModGuts (ModGuts { mg_types = type_env,
1496 = vcat [ ppr_types [] type_env,
1499 ppr_types :: [Instance] -> TypeEnv -> SDoc
1500 ppr_types insts type_env
1501 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1503 dfun_ids = map instanceDFunId insts
1504 ids = [id | id <- typeEnvIds type_env, want_sig id]
1505 want_sig id | opt_PprStyle_Debug = True
1506 | otherwise = isLocalId id &&
1507 isExternalName (idName id) &&
1508 not (id `elem` dfun_ids)
1509 -- isLocalId ignores data constructors, records selectors etc.
1510 -- The isExternalName ignores local dictionary and method bindings
1511 -- that the type checker has invented. Top-level user-defined things
1512 -- have External names.
1514 ppr_tycons :: [FamInst] -> TypeEnv -> SDoc
1515 ppr_tycons fam_insts type_env
1516 = text "TYPE CONSTRUCTORS" $$ nest 4 (ppr_tydecls tycons)
1518 fi_tycons = map famInstTyCon fam_insts
1519 tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
1520 want_tycon tycon | opt_PprStyle_Debug = True
1521 | otherwise = not (isImplicitTyCon tycon) &&
1522 isExternalName (tyConName tycon) &&
1523 not (tycon `elem` fi_tycons)
1525 ppr_insts :: [Instance] -> SDoc
1526 ppr_insts [] = empty
1527 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1529 ppr_fam_insts :: [FamInst] -> SDoc
1530 ppr_fam_insts [] = empty
1531 ppr_fam_insts fam_insts =
1532 text "FAMILY INSTANCES" $$ nest 2 (pprFamInsts fam_insts)
1534 ppr_sigs :: [Var] -> SDoc
1536 -- Print type signatures; sort by OccName
1537 = vcat (map ppr_sig (sortLe le_sig ids))
1539 le_sig id1 id2 = getOccName id1 <= getOccName id2
1540 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1542 ppr_tydecls :: [TyCon] -> SDoc
1544 -- Print type constructor info; sort by OccName
1545 = vcat (map ppr_tycon (sortLe le_sig tycons))
1547 le_sig tycon1 tycon2 = getOccName tycon1 <= getOccName tycon2
1549 | isCoercionTyCon tycon = ptext (sLit "coercion") <+> ppr tycon
1550 | otherwise = ppr (tyThingToIfaceDecl (ATyCon tycon))
1552 ppr_rules :: [CoreRule] -> SDoc
1553 ppr_rules [] = empty
1554 ppr_rules rs = vcat [ptext (sLit "{-# RULES"),
1555 nest 4 (pprRules rs),
1558 ppr_gen_tycons [] = empty
1559 ppr_gen_tycons tcs = vcat [ptext (sLit "Tycons with generics:"),
1560 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]