2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
5 \section[TcModule]{Typechecking a whole module}
10 tcRnStmt, tcRnExpr, tcRnType,
21 #include "HsVersions.h"
25 import {-# SOURCE #-} TcSplice ( tcSpliceDecls )
88 import {- Kind parts of -} Type
90 import Foreign.Ptr( Ptr )
98 import Control.Monad ( unless )
99 import Data.Maybe ( isJust )
105 %************************************************************************
107 Typecheck and rename a module
109 %************************************************************************
115 -> Bool -- True <=> save renamed syntax
116 -> Located (HsModule RdrName)
117 -> IO (Messages, Maybe TcGblEnv)
119 tcRnModule hsc_env hsc_src save_rn_syntax
120 (L loc (HsModule maybe_mod export_ies
121 import_decls local_decls mod_deprec _
122 module_info maybe_doc))
123 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
125 let { this_pkg = thisPackage (hsc_dflags hsc_env) ;
126 this_mod = case maybe_mod of
127 Nothing -> mAIN -- 'module M where' is omitted
128 Just (L _ mod) -> mkModule this_pkg mod } ;
131 initTc hsc_env hsc_src save_rn_syntax this_mod $
133 do { -- Deal with imports;
134 tcg_env <- tcRnImports hsc_env this_mod import_decls ;
135 setGblEnv tcg_env $ do {
137 -- Load the hi-boot interface for this module, if any
138 -- We do this now so that the boot_names can be passed
139 -- to tcTyAndClassDecls, because the boot_names are
140 -- automatically considered to be loop breakers
142 -- Do this *after* tcRnImports, so that we know whether
143 -- a module that we import imports us; and hence whether to
144 -- look for a hi-boot file
145 boot_iface <- tcHiBootIface hsc_src this_mod ;
147 -- Rename and type check the declarations
148 traceRn (text "rn1a") ;
149 tcg_env <- if isHsBoot hsc_src then
150 tcRnHsBootDecls local_decls
152 tcRnSrcDecls boot_iface local_decls ;
153 setGblEnv tcg_env $ do {
155 -- Report the use of any deprecated things
156 -- We do this *before* processsing the export list so
157 -- that we don't bleat about re-exporting a deprecated
158 -- thing (especially via 'module Foo' export item)
159 -- That is, only uses in the *body* of the module are complained about
160 traceRn (text "rn3") ;
161 failIfErrsM ; -- finishDeprecations crashes sometimes
162 -- as a result of typechecker repairs (e.g. unboundNames)
163 tcg_env <- finishDeprecations (hsc_dflags hsc_env) mod_deprec tcg_env ;
165 -- Process the export list
166 tcg_env <- rnExports (isJust maybe_mod) export_ies tcg_env ;
167 traceRn (text "rn4") ;
169 -- Compare the hi-boot iface (if any) with the real thing
170 -- Must be done after processing the exports
171 tcg_env <- checkHiBootIface tcg_env boot_iface ;
173 -- Make the new type env available to stuff slurped from interface files
174 -- Must do this after checkHiBootIface, because the latter might add new
175 -- bindings for boot_dfuns, which may be mentioned in imported unfoldings
176 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
178 -- Rename the Haddock documentation
179 tcg_env <- rnHaddock module_info maybe_doc tcg_env ;
181 -- Report unused names
182 reportUnusedNames export_ies tcg_env ;
184 -- Dump output and return
191 %************************************************************************
195 %************************************************************************
198 tcRnImports :: HscEnv -> Module -> [LImportDecl RdrName] -> TcM TcGblEnv
199 tcRnImports hsc_env this_mod import_decls
200 = do { (rn_imports, rdr_env, imports,hpc_info) <- rnImports import_decls ;
202 ; let { dep_mods :: ModuleNameEnv (ModuleName, IsBootInterface)
203 ; dep_mods = imp_dep_mods imports
205 -- We want instance declarations from all home-package
206 -- modules below this one, including boot modules, except
207 -- ourselves. The 'except ourselves' is so that we don't
208 -- get the instances from this module's hs-boot file
209 ; want_instances :: ModuleName -> Bool
210 ; want_instances mod = mod `elemUFM` dep_mods
211 && mod /= moduleName this_mod
212 ; (home_insts, home_fam_insts) = hptInstances hsc_env
216 -- Record boot-file info in the EPS, so that it's
217 -- visible to loadHiBootInterface in tcRnSrcDecls,
218 -- and any other incrementally-performed imports
219 ; updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
221 -- Update the gbl env
222 ; updGblEnv ( \ gbl ->
224 tcg_rdr_env = plusOccEnv (tcg_rdr_env gbl) rdr_env,
225 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
226 tcg_rn_imports = fmap (const rn_imports) (tcg_rn_imports gbl),
227 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
228 tcg_fam_inst_env = extendFamInstEnvList (tcg_fam_inst_env gbl)
233 ; traceRn (text "rn1" <+> ppr (imp_dep_mods imports))
234 -- Fail if there are any errors so far
235 -- The error printing (if needed) takes advantage
236 -- of the tcg_env we have now set
237 -- ; traceIf (text "rdr_env: " <+> ppr rdr_env)
240 -- Load any orphan-module and family instance-module
241 -- interfaces, so that their rules and instance decls will be
243 ; loadOrphanModules (imp_orphs imports) False
244 ; loadOrphanModules (imp_finsts imports) True
246 -- Check type-familily consistency
247 ; traceRn (text "rn1: checking family instance consistency")
248 ; let { dir_imp_mods = map (\ (mod, _) -> mod)
252 ; checkFamInstConsistency (imp_finsts imports) dir_imp_mods ;
258 %************************************************************************
260 Type-checking external-core modules
262 %************************************************************************
265 tcRnExtCore :: HscEnv
267 -> IO (Messages, Maybe ModGuts)
268 -- Nothing => some error occurred
270 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
271 -- The decls are IfaceDecls; all names are original names
272 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
274 initTc hsc_env ExtCoreFile False this_mod $ do {
276 let { ldecls = map noLoc decls } ;
278 -- Deal with the type declarations; first bring their stuff
279 -- into scope, then rname them, then type check them
280 tcg_env <- importsFromLocalDecls (mkFakeGroup ldecls) ;
282 setGblEnv tcg_env $ do {
284 rn_decls <- rnTyClDecls ldecls ;
287 -- Dump trace of renaming part
288 rnDump (ppr rn_decls) ;
290 -- Typecheck them all together so that
291 -- any mutually recursive types are done right
292 tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails rn_decls) ;
293 -- Make the new type env available to stuff slurped from interface files
295 setGblEnv tcg_env $ do {
297 -- Now the core bindings
298 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
302 bndrs = bindersOfBinds core_binds ;
303 my_exports = map (Avail . idName) bndrs ;
304 -- ToDo: export the data types also?
306 final_type_env = extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
308 mod_guts = ModGuts { mg_module = this_mod,
310 mg_usages = [], -- ToDo: compute usage
311 mg_dir_imps = [], -- ??
312 mg_deps = noDependencies, -- ??
313 mg_exports = my_exports,
314 mg_types = final_type_env,
315 mg_insts = tcg_insts tcg_env,
316 mg_fam_insts = tcg_fam_insts tcg_env,
317 mg_inst_env = tcg_inst_env tcg_env,
318 mg_fam_inst_env = tcg_fam_inst_env tcg_env,
320 mg_binds = core_binds,
323 mg_rdr_env = emptyGlobalRdrEnv,
324 mg_fix_env = emptyFixityEnv,
325 mg_deprecs = NoDeprecs,
326 mg_foreign = NoStubs,
327 mg_hpc_info = emptyHpcInfo False,
328 mg_modBreaks = emptyModBreaks,
329 mg_vect_info = noVectInfo
332 tcCoreDump mod_guts ;
337 mkFakeGroup decls -- Rather clumsy; lots of unused fields
338 = emptyRdrGroup { hs_tyclds = decls }
342 %************************************************************************
344 Type-checking the top level of a module
346 %************************************************************************
349 tcRnSrcDecls :: ModDetails -> [LHsDecl RdrName] -> TcM TcGblEnv
350 -- Returns the variables free in the decls
351 -- Reason: solely to report unused imports and bindings
352 tcRnSrcDecls boot_iface decls
353 = do { -- Do all the declarations
354 (tc_envs, lie) <- getLIE $ tc_rn_src_decls boot_iface decls ;
356 -- Finish simplifying class constraints
358 -- tcSimplifyTop deals with constant or ambiguous InstIds.
359 -- How could there be ambiguous ones? They can only arise if a
360 -- top-level decl falls under the monomorphism restriction
361 -- and no subsequent decl instantiates its type.
363 -- We do this after checkMain, so that we use the type info
364 -- thaat checkMain adds
366 -- We do it with both global and local env in scope:
367 -- * the global env exposes the instances to tcSimplifyTop
368 -- * the local env exposes the local Ids to tcSimplifyTop,
369 -- so that we get better error messages (monomorphism restriction)
370 traceTc (text "Tc8") ;
371 inst_binds <- setEnvs tc_envs (tcSimplifyTop lie) ;
373 -- Backsubstitution. This must be done last.
374 -- Even tcSimplifyTop may do some unification.
375 traceTc (text "Tc9") ;
376 let { (tcg_env, _) = tc_envs
377 ; TcGblEnv { tcg_type_env = type_env, tcg_binds = binds,
378 tcg_rules = rules, tcg_fords = fords } = tcg_env
379 ; all_binds = binds `unionBags` inst_binds } ;
381 (bind_ids, binds', fords', rules') <- zonkTopDecls all_binds rules fords ;
383 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
384 ; tcg_env' = tcg_env { tcg_type_env = final_type_env,
387 tcg_fords = fords' } } ;
389 return (tcg_env' { tcg_binds = tcg_binds tcg_env' })
392 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
393 -- Loops around dealing with each top level inter-splice group
394 -- in turn, until it's dealt with the entire module
395 tc_rn_src_decls boot_details ds
396 = do { let { (first_group, group_tail) = findSplice ds } ;
397 -- If ds is [] we get ([], Nothing)
399 -- Deal with decls up to, but not including, the first splice
400 (tcg_env, rn_decls) <- checkNoErrs $ rnTopSrcDecls first_group ;
401 -- checkNoErrs: stop if renaming fails
403 (tcg_env, tcl_env) <- setGblEnv tcg_env $
404 tcTopSrcDecls boot_details rn_decls ;
406 -- If there is no splice, we're nearly done
407 setEnvs (tcg_env, tcl_env) $
409 Nothing -> do { tcg_env <- checkMain ; -- Check for `main'
410 return (tcg_env, tcl_env)
413 -- If there's a splice, we must carry on
414 Just (SpliceDecl splice_expr, rest_ds) -> do {
416 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
419 -- Rename the splice expression, and get its supporting decls
420 (rn_splice_expr, splice_fvs) <- checkNoErrs (rnLExpr splice_expr) ;
421 -- checkNoErrs: don't typecheck if renaming failed
422 rnDump (ppr rn_splice_expr) ;
424 -- Execute the splice
425 spliced_decls <- tcSpliceDecls rn_splice_expr ;
427 -- Glue them on the front of the remaining decls and loop
428 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
429 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
434 %************************************************************************
436 Compiling hs-boot source files, and
437 comparing the hi-boot interface with the real thing
439 %************************************************************************
442 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
443 tcRnHsBootDecls decls
444 = do { let { (first_group, group_tail) = findSplice decls }
447 Just stuff -> spliceInHsBootErr stuff
450 -- Rename the declarations
451 ; (tcg_env, rn_group) <- rnTopSrcDecls first_group
452 ; setGblEnv tcg_env $ do {
454 -- Todo: check no foreign decls, no rules, no default decls
456 -- Typecheck type/class decls
457 ; traceTc (text "Tc2")
458 ; let tycl_decls = hs_tyclds rn_group
459 ; tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails tycl_decls)
460 ; setGblEnv tcg_env $ do {
462 -- Typecheck instance decls
463 ; traceTc (text "Tc3")
464 ; (tcg_env, inst_infos, _deriv_binds)
465 <- tcInstDecls1 tycl_decls (hs_instds rn_group) (hs_derivds rn_group)
466 ; setGblEnv tcg_env $ do {
468 -- Typecheck value declarations
469 ; traceTc (text "Tc5")
470 ; val_ids <- tcHsBootSigs (hs_valds rn_group)
473 -- No simplification or zonking to do
474 ; traceTc (text "Tc7a")
475 ; gbl_env <- getGblEnv
477 -- Make the final type-env
478 -- Include the dfun_ids so that their type sigs
479 -- are written into the interface file
480 ; let { type_env0 = tcg_type_env gbl_env
481 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
482 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
483 ; dfun_ids = map iDFunId inst_infos }
484 ; return (gbl_env { tcg_type_env = type_env2 })
487 spliceInHsBootErr (SpliceDecl (L loc _), _)
488 = addErrAt loc (ptext SLIT("Splices are not allowed in hs-boot files"))
491 Once we've typechecked the body of the module, we want to compare what
492 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
495 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM TcGblEnv
496 -- Compare the hi-boot file for this module (if there is one)
497 -- with the type environment we've just come up with
498 -- In the common case where there is no hi-boot file, the list
499 -- of boot_names is empty.
501 -- The bindings we return give bindings for the dfuns defined in the
502 -- hs-boot file, such as $fbEqT = $fEqT
505 tcg_env@(TcGblEnv { tcg_src = hs_src, tcg_binds = binds,
506 tcg_insts = local_insts, tcg_fam_insts = local_fam_insts,
507 tcg_type_env = local_type_env, tcg_exports = local_exports })
508 (ModDetails { md_insts = boot_insts, md_fam_insts = boot_fam_insts,
509 md_types = boot_type_env, md_exports = boot_exports })
510 | isHsBoot hs_src -- Current module is already a hs-boot file!
514 = do { traceTc (text "checkHiBootIface" <+> (ppr boot_type_env $$ ppr boot_insts $$
517 -- Check the exports of the boot module, one by one
518 ; mapM_ check_export boot_exports
520 -- Check instance declarations
521 ; mb_dfun_prs <- mapM check_inst boot_insts
522 ; let tcg_env' = tcg_env { tcg_binds = binds `unionBags` dfun_binds,
523 tcg_type_env = extendTypeEnvWithIds local_type_env boot_dfuns }
524 dfun_prs = catMaybes mb_dfun_prs
525 boot_dfuns = map fst dfun_prs
526 dfun_binds = listToBag [ noLoc $ VarBind boot_dfun (nlHsVar dfun)
527 | (boot_dfun, dfun) <- dfun_prs ]
529 -- Check for no family instances
530 ; unless (null boot_fam_insts) $
531 panic ("TcRnDriver.checkHiBootIface: Cannot handle family " ++
532 "instances in boot files yet...")
533 -- FIXME: Why? The actual comparison is not hard, but what would
534 -- be the equivalent to the dfun bindings returned for class
535 -- instances? We can't easily equate tycons...
539 check_export boot_avail -- boot_avail is exported by the boot iface
540 | name `elem` dfun_names = return ()
541 | isWiredInName name = return () -- No checking for wired-in names. In particular,
542 -- 'error' is handled by a rather gross hack
543 -- (see comments in GHC.Err.hs-boot)
545 -- Check that the actual module exports the same thing
546 | not (null missing_names)
547 = addErrTc (missingBootThing (head missing_names) "exported by")
549 -- If the boot module does not *define* the thing, we are done
550 -- (it simply re-exports it, and names match, so nothing further to do)
551 | isNothing mb_boot_thing = return ()
553 -- Check that the actual module also defines the thing, and
554 -- then compare the definitions
555 | Just real_thing <- lookupTypeEnv local_type_env name
556 = do { let boot_decl = tyThingToIfaceDecl (fromJust mb_boot_thing)
557 real_decl = tyThingToIfaceDecl real_thing
558 ; checkTc (checkBootDecl boot_decl real_decl)
559 (bootMisMatch real_thing boot_decl real_decl) }
560 -- The easiest way to check compatibility is to convert to
561 -- iface syntax, where we already have good comparison functions
564 = addErrTc (missingBootThing name "defined in")
566 name = availName boot_avail
567 mb_boot_thing = lookupTypeEnv boot_type_env name
568 missing_names = case lookupNameEnv local_export_env name of
570 Just avail -> availNames boot_avail `minusList` availNames avail
572 dfun_names = map getName boot_insts
574 local_export_env :: NameEnv AvailInfo
575 local_export_env = availsToNameEnv local_exports
577 check_inst :: Instance -> TcM (Maybe (Id, Id))
578 -- Returns a pair of the boot dfun in terms of the equivalent real dfun
580 = case [dfun | inst <- local_insts,
581 let dfun = instanceDFunId inst,
582 idType dfun `tcEqType` boot_inst_ty ] of
583 [] -> do { addErrTc (instMisMatch boot_inst); return Nothing }
584 (dfun:_) -> return (Just (local_boot_dfun, dfun))
586 boot_dfun = instanceDFunId boot_inst
587 boot_inst_ty = idType boot_dfun
588 local_boot_dfun = Id.mkExportedLocalId (idName boot_dfun) boot_inst_ty
592 missingBootThing thing what
593 = ppr thing <+> ptext SLIT("is exported by the hs-boot file, but not")
594 <+> text what <+> ptext SLIT("the module")
596 bootMisMatch thing boot_decl real_decl
597 = vcat [ppr thing <+> ptext SLIT("has conflicting definitions in the module and its hs-boot file"),
598 ptext SLIT("Main module:") <+> ppr real_decl,
599 ptext SLIT("Boot file: ") <+> ppr boot_decl]
603 2 (ptext SLIT("is defined in the hs-boot file, but not in the module itself"))
607 %************************************************************************
609 Type-checking the top level of a module
611 %************************************************************************
613 tcRnGroup takes a bunch of top-level source-code declarations, and
615 * gets supporting declarations from interface files
618 * and augments the TcGblEnv with the results
620 In Template Haskell it may be called repeatedly for each group of
621 declarations. It expects there to be an incoming TcGblEnv in the
622 monad; it augments it and returns the new TcGblEnv.
625 ------------------------------------------------
626 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
628 = do { -- Bring top level binders into scope
629 tcg_env <- importsFromLocalDecls group ;
630 setGblEnv tcg_env $ do {
632 failIfErrsM ; -- No point in continuing if (say) we have duplicate declarations
634 -- Rename the source decls
635 (tcg_env, rn_decls) <- rnSrcDecls group ;
638 -- save the renamed syntax, if we want it
640 | Just grp <- tcg_rn_decls tcg_env
641 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
645 -- Dump trace of renaming part
646 rnDump (ppr rn_decls) ;
648 return (tcg_env', rn_decls)
651 ------------------------------------------------
652 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
653 tcTopSrcDecls boot_details
654 (HsGroup { hs_tyclds = tycl_decls,
655 hs_instds = inst_decls,
656 hs_derivds = deriv_decls,
657 hs_fords = foreign_decls,
658 hs_defds = default_decls,
659 hs_ruleds = rule_decls,
660 hs_valds = val_binds })
661 = do { -- Type-check the type and class decls, and all imported decls
662 -- The latter come in via tycl_decls
663 traceTc (text "Tc2") ;
665 tcg_env <- checkNoErrs (tcTyAndClassDecls boot_details tycl_decls) ;
666 -- tcTyAndClassDecls recovers internally, but if anything gave rise to
667 -- an error we'd better stop now, to avoid a cascade
669 -- Make these type and class decls available to stuff slurped from interface files
670 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
673 setGblEnv tcg_env $ do {
674 -- Source-language instances, including derivings,
675 -- and import the supporting declarations
676 traceTc (text "Tc3") ;
677 (tcg_env, inst_infos, deriv_binds)
678 <- tcInstDecls1 tycl_decls inst_decls deriv_decls;
679 setGblEnv tcg_env $ do {
681 -- Foreign import declarations next. No zonking necessary
682 -- here; we can tuck them straight into the global environment.
683 traceTc (text "Tc4") ;
684 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
685 tcExtendGlobalValEnv fi_ids $ do {
687 -- Default declarations
688 traceTc (text "Tc4a") ;
689 default_tys <- tcDefaults default_decls ;
690 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
692 -- Value declarations next
693 -- We also typecheck any extra binds that came out
694 -- of the "deriving" process (deriv_binds)
695 traceTc (text "Tc5") ;
696 (tc_val_binds, tcl_env) <- tcTopBinds val_binds ;
697 setLclTypeEnv tcl_env $ do {
699 -- Now GHC-generated derived bindings and generics.
700 -- Do not generate warnings from compiler-generated code.
701 (tc_deriv_binds, tcl_env) <- discardWarnings $
702 tcTopBinds deriv_binds ;
704 -- Second pass over class and instance declarations,
705 traceTc (text "Tc6") ;
706 (inst_binds, tcl_env) <- setLclTypeEnv tcl_env $ tcInstDecls2 tycl_decls inst_infos ;
707 showLIE (text "after instDecls2") ;
710 -- They need to be zonked, so we return them
711 traceTc (text "Tc7") ;
712 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
715 rules <- tcRules rule_decls ;
718 traceTc (text "Tc7a") ;
719 tcg_env <- getGblEnv ;
720 let { all_binds = tc_val_binds `unionBags`
721 tc_deriv_binds `unionBags`
722 inst_binds `unionBags`
725 -- Extend the GblEnv with the (as yet un-zonked)
726 -- bindings, rules, foreign decls
727 tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds,
728 tcg_rules = tcg_rules tcg_env ++ rules,
729 tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
730 return (tcg_env', tcl_env)
735 %************************************************************************
739 %************************************************************************
742 checkMain :: TcM TcGblEnv
743 -- If we are in module Main, check that 'main' is defined.
745 = do { tcg_env <- getGblEnv ;
747 check_main dflags tcg_env
750 check_main dflags tcg_env
752 = traceTc (text "checkMain not" <+> ppr main_mod <+> ppr mod) >>
756 = do { mb_main <- lookupSrcOcc_maybe main_fn
757 -- Check that 'main' is in scope
758 -- It might be imported from another module!
760 Nothing -> do { traceTc (text "checkMain fail" <+> ppr main_mod <+> ppr main_fn)
765 { traceTc (text "checkMain found" <+> ppr main_mod <+> ppr main_fn)
766 ; let { rhs = nlHsApp (nlHsVar runMainIOName) (nlHsVar main_name) }
767 -- :Main.main :: IO () = runMainIO main
769 ; (main_expr, ty) <- addErrCtxt mainCtxt $
770 setSrcSpan (srcLocSpan (getSrcLoc main_name)) $
773 -- See Note [Root-main Id]
774 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
775 (mkVarOccFS FSLIT("main"))
776 (getSrcSpan main_name)
777 ; root_main_id = Id.mkExportedLocalId root_main_name ty
778 ; main_bind = noLoc (VarBind root_main_id main_expr) }
780 ; return (tcg_env { tcg_binds = tcg_binds tcg_env
782 tcg_dus = tcg_dus tcg_env
783 `plusDU` usesOnly (unitFV main_name)
784 -- Record the use of 'main', so that we don't
785 -- complain about it being defined but not used
789 mod = tcg_mod tcg_env
790 main_mod = mainModIs dflags
791 main_is_flag = mainFunIs dflags
793 main_fn = case main_is_flag of
794 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn))
795 Nothing -> main_RDR_Unqual
797 complain_no_main | ghcLink dflags == LinkInMemory = return ()
798 | otherwise = failWithTc noMainMsg
799 -- In interactive mode, don't worry about the absence of 'main'
800 -- In other modes, fail altogether, so that we don't go on
801 -- and complain a second time when processing the export list.
803 mainCtxt = ptext SLIT("When checking the type of the") <+> pp_main_fn
804 noMainMsg = ptext SLIT("The") <+> pp_main_fn
805 <+> ptext SLIT("is not defined in module") <+> quotes (ppr main_mod)
806 pp_main_fn | isJust main_is_flag = ptext SLIT("main function") <+> quotes (ppr main_fn)
807 | otherwise = ptext SLIT("function") <+> quotes (ppr main_fn)
812 The function that the RTS invokes is always :Main.main, which we call
813 root_main_id. (Because GHC allows the user to have a module not
814 called Main as the main module, we can't rely on the main function
815 being called "Main.main". That's why root_main_id has a fixed module
818 This is unusual: it's a LocalId whose Name has a Module from another
819 module. Tiresomely, we must filter it out again in MkIface, les we
820 get two defns for 'main' in the interface file!
823 %*********************************************************
827 %*********************************************************
831 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
832 setInteractiveContext hsc_env icxt thing_inside
834 -- Initialise the tcg_inst_env with instances
835 -- from all home modules. This mimics the more selective
836 -- call to hptInstances in tcRnModule
837 dfuns = fst (hptInstances hsc_env (\mod -> True))
839 updGblEnv (\env -> env {
840 tcg_rdr_env = ic_rn_gbl_env icxt,
841 tcg_inst_env = extendInstEnvList (tcg_inst_env env) dfuns }) $
844 tcExtendGhciEnv (ic_tmp_ids icxt) $
845 -- tcExtendGhciEnv does lots:
846 -- - it extends the local type env (tcl_env) with the given Ids,
847 -- - it extends the local rdr env (tcl_rdr) with the Names from
849 -- - it adds the free tyvars of the Ids to the tcl_tyvars
852 -- later ids in ic_tmp_ids must shadow earlier ones with the same
853 -- OccName, and tcExtendIdEnv implements this behaviour.
855 do { traceTc (text "setIC" <+> ppr (ic_tmp_ids icxt))
862 -> InteractiveContext
864 -> IO (Maybe ([Id], LHsExpr Id))
865 -- The returned [Id] is the list of new Ids bound by
866 -- this statement. It can be used to extend the
867 -- InteractiveContext via extendInteractiveContext.
869 -- The returned TypecheckedHsExpr is of type IO [ () ],
870 -- a list of the bound values, coerced to ().
872 tcRnStmt hsc_env ictxt rdr_stmt
873 = initTcPrintErrors hsc_env iNTERACTIVE $
874 setInteractiveContext hsc_env ictxt $ do {
876 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
877 (([rn_stmt], _), fvs) <- rnStmts DoExpr [rdr_stmt] (return ((), emptyFVs)) ;
878 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
880 rnDump (ppr rn_stmt) ;
882 -- The real work is done here
883 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
884 zonked_expr <- zonkTopLExpr tc_expr ;
885 zonked_ids <- zonkTopBndrs bound_ids ;
887 -- None of the Ids should be of unboxed type, because we
888 -- cast them all to HValues in the end!
889 mappM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
891 traceTc (text "tcs 1") ;
892 let { -- (a) Make all the bound ids "global" ids, now that
893 -- they're notionally top-level bindings. This is
894 -- important: otherwise when we come to compile an expression
895 -- using these ids later, the byte code generator will consider
896 -- the occurrences to be free rather than global.
898 -- (b) Tidy their types; this is important, because :info may
899 -- ask to look at them, and :info expects the things it looks
900 -- up to have tidy types
901 global_ids = map globaliseAndTidy zonked_ids ;
903 {- ---------------------------------------------
904 At one stage I removed any shadowed bindings from the type_env;
905 they are inaccessible but might, I suppose, cause a space leak if we leave them there.
906 However, with Template Haskell they aren't necessarily inaccessible. Consider this
908 Prelude> let f n = n * 2 :: Int
909 Prelude> fName <- runQ [| f |]
910 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
912 Prelude> let f n = n * 3 :: Int
913 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
914 In the last line we use 'fName', which resolves to the *first* 'f'
915 in scope. If we delete it from the type env, GHCi crashes because
916 it doesn't expect that.
918 Hence this code is commented out
920 -------------------------------------------------- -}
923 dumpOptTcRn Opt_D_dump_tc
924 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
925 text "Typechecked expr" <+> ppr zonked_expr]) ;
927 returnM (global_ids, zonked_expr)
930 bad_unboxed id = addErr (sep [ptext SLIT("GHCi can't bind a variable of unlifted type:"),
931 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
933 globaliseAndTidy :: Id -> Id
935 -- Give the Id a Global Name, and tidy its type
936 = Id.setIdType (globaliseId VanillaGlobal id) tidy_type
938 tidy_type = tidyTopType (idType id)
941 Here is the grand plan, implemented in tcUserStmt
943 What you type The IO [HValue] that hscStmt returns
944 ------------- ------------------------------------
945 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
948 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
951 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
952 [NB: result not printed] bindings: [it]
954 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
955 result showable) bindings: [it]
957 expr (of non-IO type,
958 result not showable) ==> error
962 ---------------------------
963 type PlanResult = ([Id], LHsExpr Id)
964 type Plan = TcM PlanResult
966 runPlans :: [Plan] -> TcM PlanResult
967 -- Try the plans in order. If one fails (by raising an exn), try the next.
968 -- If one succeeds, take it.
969 runPlans [] = panic "runPlans"
971 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
974 mkPlan :: LStmt Name -> TcM PlanResult
975 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
976 = do { uniq <- newUnique -- is treated very specially
977 ; let fresh_it = itName uniq
978 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
979 matches = [mkMatch [] expr emptyLocalBinds]
980 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
981 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
982 (HsVar bindIOName) noSyntaxExpr
983 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
984 (HsVar thenIOName) placeHolderType
987 -- [it <- e; print it] but not if it::()
989 -- [let it = e; print it]
990 ; runPlans [ -- Plan A
991 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
992 ; it_ty <- zonkTcType (idType it_id)
993 ; ifM (isUnitTy it_ty) failM
996 -- Plan B; a naked bind statment
997 tcGhciStmts [bind_stmt],
999 -- Plan C; check that the let-binding is typeable all by itself.
1000 -- If not, fail; if so, try to print it.
1001 -- The two-step process avoids getting two errors: one from
1002 -- the expression itself, and one from the 'print it' part
1003 -- This two-step story is very clunky, alas
1004 do { checkNoErrs (tcGhciStmts [let_stmt])
1005 --- checkNoErrs defeats the error recovery of let-bindings
1006 ; tcGhciStmts [let_stmt, print_it] }
1009 mkPlan stmt@(L loc (BindStmt {}))
1010 | [L _ v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
1011 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
1012 (HsVar thenIOName) placeHolderType
1014 ; print_bind_result <- doptM Opt_PrintBindResult
1015 ; let print_plan = do
1016 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
1017 ; v_ty <- zonkTcType (idType v_id)
1018 ; ifM (isUnitTy v_ty || not (isTauTy v_ty)) failM
1022 -- [stmt; print v] but not if v::()
1024 ; runPlans ((if print_bind_result then [print_plan] else []) ++
1025 [tcGhciStmts [stmt]])
1029 = tcGhciStmts [stmt]
1031 ---------------------------
1032 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1034 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1035 ret_id <- tcLookupId returnIOName ; -- return @ IO
1037 io_ty = mkTyConApp ioTyCon [] ;
1038 ret_ty = mkListTy unitTy ;
1039 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1040 tc_io_stmts stmts = tcStmts DoExpr (tcDoStmt io_ty) stmts
1041 (emptyRefinement, io_ret_ty) ;
1043 names = map unLoc (collectLStmtsBinders stmts) ;
1045 -- mk_return builds the expression
1046 -- returnIO @ [()] [coerce () x, .., coerce () z]
1048 -- Despite the inconvenience of building the type applications etc,
1049 -- this *has* to be done in type-annotated post-typecheck form
1050 -- because we are going to return a list of *polymorphic* values
1051 -- coerced to type (). If we built a *source* stmt
1052 -- return [coerce x, ..., coerce z]
1053 -- then the type checker would instantiate x..z, and we wouldn't
1054 -- get their *polymorphic* values. (And we'd get ambiguity errs
1055 -- if they were overloaded, since they aren't applied to anything.)
1056 mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty])
1057 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1058 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1062 -- OK, we're ready to typecheck the stmts
1063 traceTc (text "TcRnDriver.tcGhciStmts: tc stmts") ;
1064 ((tc_stmts, ids), lie) <- getLIE $ tc_io_stmts stmts $ \ _ ->
1065 mappM tcLookupId names ;
1066 -- Look up the names right in the middle,
1067 -- where they will all be in scope
1069 -- Simplify the context
1070 traceTc (text "TcRnDriver.tcGhciStmts: simplify ctxt") ;
1071 const_binds <- checkNoErrs (tcSimplifyInteractive lie) ;
1072 -- checkNoErrs ensures that the plan fails if context redn fails
1074 traceTc (text "TcRnDriver.tcGhciStmts: done") ;
1075 return (ids, mkHsDictLet const_binds $
1076 noLoc (HsDo DoExpr tc_stmts (mk_return ids) io_ret_ty))
1081 tcRnExpr just finds the type of an expression
1085 -> InteractiveContext
1088 tcRnExpr hsc_env ictxt rdr_expr
1089 = initTcPrintErrors hsc_env iNTERACTIVE $
1090 setInteractiveContext hsc_env ictxt $ do {
1092 (rn_expr, fvs) <- rnLExpr rdr_expr ;
1095 -- Now typecheck the expression;
1096 -- it might have a rank-2 type (e.g. :t runST)
1097 ((tc_expr, res_ty), lie) <- getLIE (tcInferRho rn_expr) ;
1098 ((qtvs, dict_insts, _), lie_top) <- getLIE (tcSimplifyInfer smpl_doc (tyVarsOfType res_ty) lie) ;
1099 tcSimplifyInteractive lie_top ;
1101 let { all_expr_ty = mkForAllTys qtvs $
1102 mkFunTys (map (idType . instToId) dict_insts) $
1104 zonkTcType all_expr_ty
1107 smpl_doc = ptext SLIT("main expression")
1110 tcRnType just finds the kind of a type
1114 -> InteractiveContext
1117 tcRnType hsc_env ictxt rdr_type
1118 = initTcPrintErrors hsc_env iNTERACTIVE $
1119 setInteractiveContext hsc_env ictxt $ do {
1121 rn_type <- rnLHsType doc rdr_type ;
1124 -- Now kind-check the type
1125 (ty', kind) <- kcHsType rn_type ;
1129 doc = ptext SLIT("In GHCi input")
1135 %************************************************************************
1137 More GHCi stuff, to do with browsing and getting info
1139 %************************************************************************
1143 -- ASSUMES that the module is either in the HomePackageTable or is
1144 -- a package module with an interface on disk. If neither of these is
1145 -- true, then the result will be an error indicating the interface
1146 -- could not be found.
1147 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe [AvailInfo])
1148 getModuleExports hsc_env mod
1151 checkMods = ic_toplev_scope ic ++ ic_exports ic
1153 initTc hsc_env HsSrcFile False iNTERACTIVE (tcGetModuleExports mod checkMods)
1155 -- Get the export avail info and also load all orphan and family-instance
1156 -- modules. Finally, check that the family instances of all modules in the
1157 -- interactive context are consistent (these modules are in the second
1159 tcGetModuleExports :: Module -> [Module] -> TcM [AvailInfo]
1160 tcGetModuleExports mod directlyImpMods
1161 = do { let doc = ptext SLIT("context for compiling statements")
1162 ; iface <- initIfaceTcRn $ loadSysInterface doc mod
1164 -- Load any orphan-module and family instance-module
1165 -- interfaces, so their instances are visible.
1166 ; loadOrphanModules (dep_orphs (mi_deps iface)) False
1167 ; loadOrphanModules (dep_finsts (mi_deps iface)) True
1169 -- Check that the family instances of all directly loaded
1170 -- modules are consistent.
1171 ; checkFamInstConsistency (dep_finsts (mi_deps iface)) directlyImpMods
1173 ; ifaceExportNames (mi_exports iface)
1176 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Maybe [Name])
1177 tcRnLookupRdrName hsc_env rdr_name
1178 = initTcPrintErrors hsc_env iNTERACTIVE $
1179 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1180 lookup_rdr_name rdr_name
1182 lookup_rdr_name rdr_name = do {
1183 -- If the identifier is a constructor (begins with an
1184 -- upper-case letter), then we need to consider both
1185 -- constructor and type class identifiers.
1186 let { rdr_names = dataTcOccs rdr_name } ;
1188 -- results :: [Either Messages Name]
1189 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1191 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1192 -- The successful lookups will be (Just name)
1193 let { (warns_s, good_names) = unzip [ (msgs, name)
1194 | (msgs, Just name) <- results] ;
1195 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1197 -- Fail if nothing good happened, else add warnings
1198 if null good_names then
1199 -- No lookup succeeded, so
1200 -- pick the first error message and report it
1201 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1202 -- while the other is "X is not in scope",
1203 -- we definitely want the former; but we might pick the latter
1204 do { addMessages (head errs_s) ; failM }
1205 else -- Add deprecation warnings
1206 mapM_ addMessages warns_s ;
1211 tcRnLookupName :: HscEnv -> Name -> IO (Maybe TyThing)
1212 tcRnLookupName hsc_env name
1213 = initTcPrintErrors hsc_env iNTERACTIVE $
1214 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1215 tcRnLookupName' name
1217 -- To look up a name we have to look in the local environment (tcl_lcl)
1218 -- as well as the global environment, which is what tcLookup does.
1219 -- But we also want a TyThing, so we have to convert:
1221 tcRnLookupName' :: Name -> TcRn TyThing
1222 tcRnLookupName' name = do
1223 tcthing <- tcLookup name
1225 AGlobal thing -> return thing
1226 ATcId{tct_id=id} -> return (AnId id)
1227 _ -> panic "tcRnLookupName'"
1229 tcRnGetInfo :: HscEnv
1231 -> IO (Maybe (TyThing, Fixity, [Instance]))
1233 -- Used to implemnent :info in GHCi
1235 -- Look up a RdrName and return all the TyThings it might be
1236 -- A capitalised RdrName is given to us in the DataName namespace,
1237 -- but we want to treat it as *both* a data constructor
1238 -- *and* as a type or class constructor;
1239 -- hence the call to dataTcOccs, and we return up to two results
1240 tcRnGetInfo hsc_env name
1241 = initTcPrintErrors hsc_env iNTERACTIVE $
1242 let ictxt = hsc_IC hsc_env in
1243 setInteractiveContext hsc_env ictxt $ do
1245 -- Load the interface for all unqualified types and classes
1246 -- That way we will find all the instance declarations
1247 -- (Packages have not orphan modules, and we assume that
1248 -- in the home package all relevant modules are loaded.)
1249 loadUnqualIfaces ictxt
1251 thing <- tcRnLookupName' name
1252 fixity <- lookupFixityRn name
1253 ispecs <- lookupInsts thing
1254 return (thing, fixity, ispecs)
1256 lookupInsts :: TyThing -> TcM [Instance]
1257 lookupInsts (AClass cls)
1258 = do { inst_envs <- tcGetInstEnvs
1259 ; return (classInstances inst_envs cls) }
1261 lookupInsts (ATyCon tc)
1262 = do { eps <- getEps -- Load all instances for all classes that are
1263 -- in the type environment (which are all the ones
1264 -- we've seen in any interface file so far)
1265 ; (pkg_ie, home_ie) <- tcGetInstEnvs -- Search all
1267 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1268 , let dfun = instanceDFunId ispec
1271 relevant df = tc_name `elemNameSet` tyClsNamesOfDFunHead (idType df)
1272 tc_name = tyConName tc
1274 lookupInsts other = return []
1276 loadUnqualIfaces :: InteractiveContext -> TcM ()
1277 -- Load the home module for everything that is in scope unqualified
1278 -- This is so that we can accurately report the instances for
1280 loadUnqualIfaces ictxt
1282 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1284 unqual_mods = [ nameModule name
1285 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1286 let name = gre_name gre,
1287 not (isInternalName name),
1288 isTcOcc (nameOccName name), -- Types and classes only
1289 unQualOK gre ] -- In scope unqualified
1290 doc = ptext SLIT("Need interface for module whose export(s) are in scope unqualified")
1294 %************************************************************************
1298 %************************************************************************
1301 rnDump :: SDoc -> TcRn ()
1302 -- Dump, with a banner, if -ddump-rn
1303 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1305 tcDump :: TcGblEnv -> TcRn ()
1307 = do { dflags <- getDOpts ;
1309 -- Dump short output if -ddump-types or -ddump-tc
1310 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1311 (dumpTcRn short_dump) ;
1313 -- Dump bindings if -ddump-tc
1314 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1317 short_dump = pprTcGblEnv env
1318 full_dump = pprLHsBinds (tcg_binds env)
1319 -- NB: foreign x-d's have undefined's in their types;
1320 -- hence can't show the tc_fords
1323 = do { dflags <- getDOpts ;
1324 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1325 (dumpTcRn (pprModGuts mod_guts)) ;
1327 -- Dump bindings if -ddump-tc
1328 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1330 full_dump = pprCoreBindings (mg_binds mod_guts)
1332 -- It's unpleasant having both pprModGuts and pprModDetails here
1333 pprTcGblEnv :: TcGblEnv -> SDoc
1334 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1336 tcg_fam_insts = fam_insts,
1338 tcg_imports = imports })
1339 = vcat [ ppr_types insts type_env
1340 , ppr_tycons fam_insts type_env
1342 , ppr_fam_insts fam_insts
1343 , vcat (map ppr rules)
1344 , ppr_gen_tycons (typeEnvTyCons type_env)
1345 , ptext SLIT("Dependent modules:") <+> ppr (eltsUFM (imp_dep_mods imports))
1346 , ptext SLIT("Dependent packages:") <+> ppr (imp_dep_pkgs imports)]
1348 pprModGuts :: ModGuts -> SDoc
1349 pprModGuts (ModGuts { mg_types = type_env,
1351 = vcat [ ppr_types [] type_env,
1354 ppr_types :: [Instance] -> TypeEnv -> SDoc
1355 ppr_types insts type_env
1356 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1358 dfun_ids = map instanceDFunId insts
1359 ids = [id | id <- typeEnvIds type_env, want_sig id]
1360 want_sig id | opt_PprStyle_Debug = True
1361 | otherwise = isLocalId id &&
1362 isExternalName (idName id) &&
1363 not (id `elem` dfun_ids)
1364 -- isLocalId ignores data constructors, records selectors etc.
1365 -- The isExternalName ignores local dictionary and method bindings
1366 -- that the type checker has invented. Top-level user-defined things
1367 -- have External names.
1369 ppr_tycons :: [FamInst] -> TypeEnv -> SDoc
1370 ppr_tycons fam_insts type_env
1371 = text "TYPE CONSTRUCTORS" $$ nest 4 (ppr_tydecls tycons)
1373 fi_tycons = map famInstTyCon fam_insts
1374 tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
1375 want_tycon tycon | opt_PprStyle_Debug = True
1376 | otherwise = not (isImplicitTyCon tycon) &&
1377 isExternalName (tyConName tycon) &&
1378 not (tycon `elem` fi_tycons)
1380 ppr_insts :: [Instance] -> SDoc
1381 ppr_insts [] = empty
1382 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1384 ppr_fam_insts :: [FamInst] -> SDoc
1385 ppr_fam_insts [] = empty
1386 ppr_fam_insts fam_insts =
1387 text "FAMILY INSTANCES" $$ nest 2 (pprFamInsts fam_insts)
1389 ppr_sigs :: [Var] -> SDoc
1391 -- Print type signatures; sort by OccName
1392 = vcat (map ppr_sig (sortLe le_sig ids))
1394 le_sig id1 id2 = getOccName id1 <= getOccName id2
1395 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1397 ppr_tydecls :: [TyCon] -> SDoc
1399 -- Print type constructor info; sort by OccName
1400 = vcat (map ppr_tycon (sortLe le_sig tycons))
1402 le_sig tycon1 tycon2 = getOccName tycon1 <= getOccName tycon2
1404 | isCoercionTyCon tycon = ptext SLIT("coercion") <+> ppr tycon
1405 | otherwise = ppr (tyThingToIfaceDecl (ATyCon tycon))
1407 ppr_rules :: [CoreRule] -> SDoc
1408 ppr_rules [] = empty
1409 ppr_rules rs = vcat [ptext SLIT("{-# RULES"),
1410 nest 4 (pprRules rs),
1413 ppr_gen_tycons [] = empty
1414 ppr_gen_tycons tcs = vcat [ptext SLIT("Tycons with generics:"),
1415 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]