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,
22 #include "HsVersions.h"
26 import {-# SOURCE #-} TcSplice ( tcSpliceDecls )
90 import {- Kind parts of -} Type
99 import Control.Monad ( unless )
104 %************************************************************************
106 Typecheck and rename a module
108 %************************************************************************
114 -> Bool -- True <=> save renamed syntax
115 -> Located (HsModule RdrName)
116 -> IO (Messages, Maybe TcGblEnv)
118 tcRnModule hsc_env hsc_src save_rn_syntax
119 (L loc (HsModule maybe_mod export_ies
120 import_decls local_decls mod_deprec _
121 module_info maybe_doc))
122 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
124 let { this_pkg = thisPackage (hsc_dflags hsc_env) ;
125 this_mod = case maybe_mod of
126 Nothing -> mAIN -- 'module M where' is omitted
127 Just (L _ mod) -> mkModule this_pkg mod } ;
130 initTc hsc_env hsc_src save_rn_syntax this_mod $
132 do { -- Deal with imports;
133 tcg_env <- tcRnImports hsc_env this_mod import_decls ;
134 setGblEnv tcg_env $ do {
136 -- Load the hi-boot interface for this module, if any
137 -- We do this now so that the boot_names can be passed
138 -- to tcTyAndClassDecls, because the boot_names are
139 -- automatically considered to be loop breakers
141 -- Do this *after* tcRnImports, so that we know whether
142 -- a module that we import imports us; and hence whether to
143 -- look for a hi-boot file
144 boot_iface <- tcHiBootIface hsc_src this_mod ;
146 -- Rename and type check the declarations
147 traceRn (text "rn1a") ;
148 tcg_env <- if isHsBoot hsc_src then
149 tcRnHsBootDecls local_decls
151 tcRnSrcDecls boot_iface local_decls ;
152 setGblEnv tcg_env $ do {
154 -- Report the use of any deprecated things
155 -- We do this *before* processsing the export list so
156 -- that we don't bleat about re-exporting a deprecated
157 -- thing (especially via 'module Foo' export item)
158 -- That is, only uses in the *body* of the module are complained about
159 traceRn (text "rn3") ;
160 failIfErrsM ; -- finishDeprecations crashes sometimes
161 -- as a result of typechecker repairs (e.g. unboundNames)
162 tcg_env <- finishDeprecations (hsc_dflags hsc_env) mod_deprec tcg_env ;
164 -- Process the export list
165 tcg_env <- rnExports (isJust maybe_mod) export_ies tcg_env ;
166 traceRn (text "rn4") ;
168 -- Compare the hi-boot iface (if any) with the real thing
169 -- Must be done after processing the exports
170 tcg_env <- checkHiBootIface tcg_env boot_iface ;
172 -- Make the new type env available to stuff slurped from interface files
173 -- Must do this after checkHiBootIface, because the latter might add new
174 -- bindings for boot_dfuns, which may be mentioned in imported unfoldings
175 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
177 -- Rename the Haddock documentation
178 tcg_env <- rnHaddock module_info maybe_doc tcg_env ;
180 -- Report unused names
181 reportUnusedNames export_ies tcg_env ;
183 -- Dump output and return
190 %************************************************************************
194 %************************************************************************
197 tcRnImports :: HscEnv -> Module -> [LImportDecl RdrName] -> TcM TcGblEnv
198 tcRnImports hsc_env this_mod import_decls
199 = do { (rn_imports, rdr_env, imports) <- rnImports import_decls ;
201 ; let { dep_mods :: ModuleNameEnv (ModuleName, IsBootInterface)
202 ; dep_mods = imp_dep_mods imports
204 -- We want instance declarations from all home-package
205 -- modules below this one, including boot modules, except
206 -- ourselves. The 'except ourselves' is so that we don't
207 -- get the instances from this module's hs-boot file
208 ; want_instances :: ModuleName -> Bool
209 ; want_instances mod = mod `elemUFM` dep_mods
210 && mod /= moduleName this_mod
211 ; home_insts = hptInstances hsc_env want_instances
214 -- Record boot-file info in the EPS, so that it's
215 -- visible to loadHiBootInterface in tcRnSrcDecls,
216 -- and any other incrementally-performed imports
217 ; updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
219 -- Update the gbl env
220 ; updGblEnv ( \ gbl ->
221 gbl { tcg_rdr_env = plusOccEnv (tcg_rdr_env gbl) rdr_env,
222 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
223 tcg_rn_imports = fmap (const rn_imports) (tcg_rn_imports gbl),
224 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts
227 ; traceRn (text "rn1" <+> ppr (imp_dep_mods imports))
228 -- Fail if there are any errors so far
229 -- The error printing (if needed) takes advantage
230 -- of the tcg_env we have now set
231 -- ; traceIf (text "rdr_env: " <+> ppr rdr_env)
234 -- Load any orphan-module and family instance-module
235 -- interfaces, so that their rules and instance decls will be
237 ; loadOrphanModules (imp_orphs imports) False
238 ; loadOrphanModules (imp_finsts imports) True
240 -- Check type-familily consistency
241 ; traceRn (text "rn1: checking family instance consistency")
242 ; let { dir_imp_mods = map (\ (mod, _, _) -> mod)
246 ; checkFamInstConsistency (imp_finsts imports) dir_imp_mods ;
252 %************************************************************************
254 Type-checking external-core modules
256 %************************************************************************
259 tcRnExtCore :: HscEnv
261 -> IO (Messages, Maybe ModGuts)
262 -- Nothing => some error occurred
264 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
265 -- The decls are IfaceDecls; all names are original names
266 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
268 initTc hsc_env ExtCoreFile False this_mod $ do {
270 let { ldecls = map noLoc decls } ;
272 -- Deal with the type declarations; first bring their stuff
273 -- into scope, then rname them, then type check them
274 tcg_env <- importsFromLocalDecls (mkFakeGroup ldecls) ;
276 setGblEnv tcg_env $ do {
278 rn_decls <- rnTyClDecls ldecls ;
281 -- Dump trace of renaming part
282 rnDump (ppr rn_decls) ;
284 -- Typecheck them all together so that
285 -- any mutually recursive types are done right
286 tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails rn_decls) ;
287 -- Make the new type env available to stuff slurped from interface files
289 setGblEnv tcg_env $ do {
291 -- Now the core bindings
292 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
296 bndrs = bindersOfBinds core_binds ;
297 my_exports = map (Avail . idName) bndrs ;
298 -- ToDo: export the data types also?
300 final_type_env = extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
302 mod_guts = ModGuts { mg_module = this_mod,
304 mg_usages = [], -- ToDo: compute usage
305 mg_dir_imps = [], -- ??
306 mg_deps = noDependencies, -- ??
307 mg_exports = my_exports,
308 mg_types = final_type_env,
309 mg_insts = tcg_insts tcg_env,
310 mg_fam_insts = tcg_fam_insts tcg_env,
311 mg_fam_inst_env = tcg_fam_inst_env tcg_env,
313 mg_binds = core_binds,
316 mg_rdr_env = emptyGlobalRdrEnv,
317 mg_fix_env = emptyFixityEnv,
318 mg_deprecs = NoDeprecs,
319 mg_foreign = NoStubs,
320 mg_hpc_info = noHpcInfo,
321 mg_dbg_sites = noDbgSites
324 tcCoreDump mod_guts ;
329 mkFakeGroup decls -- Rather clumsy; lots of unused fields
330 = emptyRdrGroup { hs_tyclds = decls }
334 %************************************************************************
336 Type-checking the top level of a module
338 %************************************************************************
341 tcRnSrcDecls :: ModDetails -> [LHsDecl RdrName] -> TcM TcGblEnv
342 -- Returns the variables free in the decls
343 -- Reason: solely to report unused imports and bindings
344 tcRnSrcDecls boot_iface decls
345 = do { -- Do all the declarations
346 (tc_envs, lie) <- getLIE $ tc_rn_src_decls boot_iface decls ;
348 -- Finish simplifying class constraints
350 -- tcSimplifyTop deals with constant or ambiguous InstIds.
351 -- How could there be ambiguous ones? They can only arise if a
352 -- top-level decl falls under the monomorphism restriction
353 -- and no subsequent decl instantiates its type.
355 -- We do this after checkMain, so that we use the type info
356 -- thaat checkMain adds
358 -- We do it with both global and local env in scope:
359 -- * the global env exposes the instances to tcSimplifyTop
360 -- * the local env exposes the local Ids to tcSimplifyTop,
361 -- so that we get better error messages (monomorphism restriction)
362 traceTc (text "Tc8") ;
363 inst_binds <- setEnvs tc_envs (tcSimplifyTop lie) ;
365 -- Backsubstitution. This must be done last.
366 -- Even tcSimplifyTop may do some unification.
367 traceTc (text "Tc9") ;
368 let { (tcg_env, _) = tc_envs
369 ; TcGblEnv { tcg_type_env = type_env, tcg_binds = binds,
370 tcg_rules = rules, tcg_fords = fords } = tcg_env
371 ; all_binds = binds `unionBags` inst_binds } ;
373 (bind_ids, binds', fords', rules') <- zonkTopDecls all_binds rules fords ;
375 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
376 ; tcg_env' = tcg_env { tcg_type_env = final_type_env,
379 tcg_fords = fords' } } ;
381 return (tcg_env' { tcg_binds = tcg_binds tcg_env' })
384 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
385 -- Loops around dealing with each top level inter-splice group
386 -- in turn, until it's dealt with the entire module
387 tc_rn_src_decls boot_details ds
388 = do { let { (first_group, group_tail) = findSplice ds } ;
389 -- If ds is [] we get ([], Nothing)
391 -- Deal with decls up to, but not including, the first splice
392 (tcg_env, rn_decls) <- checkNoErrs $ rnTopSrcDecls first_group ;
393 -- checkNoErrs: stop if renaming fails
395 (tcg_env, tcl_env) <- setGblEnv tcg_env $
396 tcTopSrcDecls boot_details rn_decls ;
398 -- If there is no splice, we're nearly done
399 setEnvs (tcg_env, tcl_env) $
401 Nothing -> do { tcg_env <- checkMain ; -- Check for `main'
402 return (tcg_env, tcl_env)
405 -- If there's a splice, we must carry on
406 Just (SpliceDecl splice_expr, rest_ds) -> do {
408 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
411 -- Rename the splice expression, and get its supporting decls
412 (rn_splice_expr, splice_fvs) <- checkNoErrs (rnLExpr splice_expr) ;
413 -- checkNoErrs: don't typecheck if renaming failed
414 rnDump (ppr rn_splice_expr) ;
416 -- Execute the splice
417 spliced_decls <- tcSpliceDecls rn_splice_expr ;
419 -- Glue them on the front of the remaining decls and loop
420 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
421 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
426 %************************************************************************
428 Compiling hs-boot source files, and
429 comparing the hi-boot interface with the real thing
431 %************************************************************************
434 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
435 tcRnHsBootDecls decls
436 = do { let { (first_group, group_tail) = findSplice decls }
439 Just stuff -> spliceInHsBootErr stuff
442 -- Rename the declarations
443 ; (tcg_env, rn_group) <- rnTopSrcDecls first_group
444 ; setGblEnv tcg_env $ do {
446 -- Todo: check no foreign decls, no rules, no default decls
448 -- Typecheck type/class decls
449 ; traceTc (text "Tc2")
450 ; let tycl_decls = hs_tyclds rn_group
451 ; tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails tycl_decls)
452 ; setGblEnv tcg_env $ do {
454 -- Typecheck instance decls
455 ; traceTc (text "Tc3")
456 ; (tcg_env, inst_infos, _deriv_binds)
457 <- tcInstDecls1 tycl_decls (hs_instds rn_group) (hs_derivds rn_group)
458 ; setGblEnv tcg_env $ do {
460 -- Typecheck value declarations
461 ; traceTc (text "Tc5")
462 ; val_ids <- tcHsBootSigs (hs_valds rn_group)
465 -- No simplification or zonking to do
466 ; traceTc (text "Tc7a")
467 ; gbl_env <- getGblEnv
469 -- Make the final type-env
470 -- Include the dfun_ids so that their type sigs
471 -- are written into the interface file
472 ; let { type_env0 = tcg_type_env gbl_env
473 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
474 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
475 ; dfun_ids = map iDFunId inst_infos }
476 ; return (gbl_env { tcg_type_env = type_env2 })
479 spliceInHsBootErr (SpliceDecl (L loc _), _)
480 = addErrAt loc (ptext SLIT("Splices are not allowed in hs-boot files"))
483 Once we've typechecked the body of the module, we want to compare what
484 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
487 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM TcGblEnv
488 -- Compare the hi-boot file for this module (if there is one)
489 -- with the type environment we've just come up with
490 -- In the common case where there is no hi-boot file, the list
491 -- of boot_names is empty.
493 -- The bindings we return give bindings for the dfuns defined in the
494 -- hs-boot file, such as $fbEqT = $fEqT
497 tcg_env@(TcGblEnv { tcg_src = hs_src, tcg_binds = binds,
498 tcg_insts = local_insts, tcg_fam_insts = local_fam_insts,
499 tcg_type_env = local_type_env, tcg_exports = local_exports })
500 (ModDetails { md_insts = boot_insts, md_fam_insts = boot_fam_insts,
501 md_types = boot_type_env, md_exports = boot_exports })
502 | isHsBoot hs_src -- Current module is already a hs-boot file!
506 = do { traceTc (text "checkHiBootIface" <+> (ppr boot_type_env $$ ppr boot_insts $$
509 -- Check the exports of the boot module, one by one
510 ; mapM_ check_export boot_exports
512 -- Check instance declarations
513 ; mb_dfun_prs <- mapM check_inst boot_insts
514 ; let tcg_env' = tcg_env { tcg_binds = binds `unionBags` dfun_binds,
515 tcg_type_env = extendTypeEnvWithIds local_type_env boot_dfuns }
516 dfun_prs = catMaybes mb_dfun_prs
517 boot_dfuns = map fst dfun_prs
518 dfun_binds = listToBag [ noLoc $ VarBind boot_dfun (nlHsVar dfun)
519 | (boot_dfun, dfun) <- dfun_prs ]
521 -- Check for no family instances
522 ; unless (null boot_fam_insts) $
523 panic ("TcRnDriver.checkHiBootIface: Cannot handle family " ++
524 "instances in boot files yet...")
525 -- FIXME: Why? The actual comparison is not hard, but what would
526 -- be the equivalent to the dfun bindings returned for class
527 -- instances? We can't easily equate tycons...
531 check_export boot_avail -- boot_avail is exported by the boot iface
532 | name `elem` dfun_names = return ()
533 | isWiredInName name = return () -- No checking for wired-in names. In particular,
534 -- 'error' is handled by a rather gross hack
535 -- (see comments in GHC.Err.hs-boot)
537 -- Check that the actual module exports the same thing
538 | not (null missing_names)
539 = addErrTc (missingBootThing (head missing_names) "exported by")
541 -- If the boot module does not *define* the thing, we are done
542 -- (it simply re-exports it, and names match, so nothing further to do)
543 | isNothing mb_boot_thing = return ()
545 -- Check that the actual module also defines the thing, and
546 -- then compare the definitions
547 | Just real_thing <- lookupTypeEnv local_type_env name
548 = do { let boot_decl = tyThingToIfaceDecl (fromJust mb_boot_thing)
549 real_decl = tyThingToIfaceDecl real_thing
550 ; checkTc (checkBootDecl boot_decl real_decl)
551 (bootMisMatch real_thing boot_decl real_decl) }
552 -- The easiest way to check compatibility is to convert to
553 -- iface syntax, where we already have good comparison functions
556 = addErrTc (missingBootThing name "defined in")
558 name = availName boot_avail
559 mb_boot_thing = lookupTypeEnv boot_type_env name
560 missing_names = case lookupNameEnv local_export_env name of
562 Just avail -> availNames boot_avail `minusList` availNames avail
564 dfun_names = map getName boot_insts
566 local_export_env :: NameEnv AvailInfo
567 local_export_env = availsToNameEnv local_exports
569 check_inst :: Instance -> TcM (Maybe (Id, Id))
570 -- Returns a pair of the boot dfun in terms of the equivalent real dfun
572 = case [dfun | inst <- local_insts,
573 let dfun = instanceDFunId inst,
574 idType dfun `tcEqType` boot_inst_ty ] of
575 [] -> do { addErrTc (instMisMatch boot_inst); return Nothing }
576 (dfun:_) -> return (Just (local_boot_dfun, dfun))
578 boot_dfun = instanceDFunId boot_inst
579 boot_inst_ty = idType boot_dfun
580 local_boot_dfun = Id.mkExportedLocalId (idName boot_dfun) boot_inst_ty
584 missingBootThing thing what
585 = ppr thing <+> ptext SLIT("is exported by the hs-boot file, but not")
586 <+> text what <+> ptext SLIT("the module")
588 bootMisMatch thing boot_decl real_decl
589 = vcat [ppr thing <+> ptext SLIT("has conflicting definitions in the module and its hs-boot file"),
590 ptext SLIT("Main module:") <+> ppr real_decl,
591 ptext SLIT("Boot file: ") <+> ppr boot_decl]
595 2 (ptext SLIT("is defined in the hs-boot file, but not in the module itself"))
599 %************************************************************************
601 Type-checking the top level of a module
603 %************************************************************************
605 tcRnGroup takes a bunch of top-level source-code declarations, and
607 * gets supporting declarations from interface files
610 * and augments the TcGblEnv with the results
612 In Template Haskell it may be called repeatedly for each group of
613 declarations. It expects there to be an incoming TcGblEnv in the
614 monad; it augments it and returns the new TcGblEnv.
617 ------------------------------------------------
618 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
620 = do { -- Bring top level binders into scope
621 tcg_env <- importsFromLocalDecls group ;
622 setGblEnv tcg_env $ do {
624 failIfErrsM ; -- No point in continuing if (say) we have duplicate declarations
626 -- Rename the source decls
627 (tcg_env, rn_decls) <- rnSrcDecls group ;
630 -- save the renamed syntax, if we want it
632 | Just grp <- tcg_rn_decls tcg_env
633 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
637 -- Dump trace of renaming part
638 rnDump (ppr rn_decls) ;
640 return (tcg_env', rn_decls)
643 ------------------------------------------------
644 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
645 tcTopSrcDecls boot_details
646 (HsGroup { hs_tyclds = tycl_decls,
647 hs_instds = inst_decls,
648 hs_derivds = deriv_decls,
649 hs_fords = foreign_decls,
650 hs_defds = default_decls,
651 hs_ruleds = rule_decls,
652 hs_valds = val_binds })
653 = do { -- Type-check the type and class decls, and all imported decls
654 -- The latter come in via tycl_decls
655 traceTc (text "Tc2") ;
657 tcg_env <- checkNoErrs (tcTyAndClassDecls boot_details tycl_decls) ;
658 -- tcTyAndClassDecls recovers internally, but if anything gave rise to
659 -- an error we'd better stop now, to avoid a cascade
661 -- Make these type and class decls available to stuff slurped from interface files
662 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
665 setGblEnv tcg_env $ do {
666 -- Source-language instances, including derivings,
667 -- and import the supporting declarations
668 traceTc (text "Tc3") ;
669 (tcg_env, inst_infos, deriv_binds)
670 <- tcInstDecls1 tycl_decls inst_decls deriv_decls;
671 setGblEnv tcg_env $ do {
673 -- Foreign import declarations next. No zonking necessary
674 -- here; we can tuck them straight into the global environment.
675 traceTc (text "Tc4") ;
676 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
677 tcExtendGlobalValEnv fi_ids $ do {
679 -- Default declarations
680 traceTc (text "Tc4a") ;
681 default_tys <- tcDefaults default_decls ;
682 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
684 -- Value declarations next
685 -- We also typecheck any extra binds that came out
686 -- of the "deriving" process (deriv_binds)
687 traceTc (text "Tc5") ;
688 (tc_val_binds, tcl_env) <- tcTopBinds (val_binds `plusHsValBinds` deriv_binds) ;
689 setLclTypeEnv tcl_env $ do {
691 -- Second pass over class and instance declarations,
692 traceTc (text "Tc6") ;
693 (inst_binds, tcl_env) <- tcInstDecls2 tycl_decls inst_infos ;
694 showLIE (text "after instDecls2") ;
697 -- They need to be zonked, so we return them
698 traceTc (text "Tc7") ;
699 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
702 rules <- tcRules rule_decls ;
705 traceTc (text "Tc7a") ;
706 tcg_env <- getGblEnv ;
707 let { all_binds = tc_val_binds `unionBags`
708 inst_binds `unionBags`
711 -- Extend the GblEnv with the (as yet un-zonked)
712 -- bindings, rules, foreign decls
713 tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds,
714 tcg_rules = tcg_rules tcg_env ++ rules,
715 tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
716 return (tcg_env', tcl_env)
721 %************************************************************************
725 %************************************************************************
728 checkMain :: TcM TcGblEnv
729 -- If we are in module Main, check that 'main' is defined.
731 = do { tcg_env <- getGblEnv ;
733 let { main_mod = mainModIs dflags ;
734 main_fn = case mainFunIs dflags of {
735 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn)) ;
736 Nothing -> main_RDR_Unqual } } ;
738 check_main dflags tcg_env main_mod main_fn
742 check_main dflags tcg_env main_mod main_fn
744 = traceTc (text "checkMain not" <+> ppr main_mod <+> ppr mod) >>
748 = addErrCtxt mainCtxt $
749 do { mb_main <- lookupSrcOcc_maybe main_fn
750 -- Check that 'main' is in scope
751 -- It might be imported from another module!
753 Nothing -> do { traceTc (text "checkMain fail" <+> ppr main_mod <+> ppr main_fn)
757 { traceTc (text "checkMain found" <+> ppr main_mod <+> ppr main_fn)
758 ; let { rhs = nlHsApp (nlHsVar runMainIOName) (nlHsVar main_name) }
759 -- :Main.main :: IO () = runMainIO main
761 ; (main_expr, ty) <- setSrcSpan (srcLocSpan (getSrcLoc main_name)) $
764 -- See Note [Root-main Id]
765 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
766 (mkVarOccFS FSLIT("main"))
767 (getSrcLoc main_name)
768 ; root_main_id = Id.mkExportedLocalId root_main_name ty
769 ; main_bind = noLoc (VarBind root_main_id main_expr) }
771 ; return (tcg_env { tcg_binds = tcg_binds tcg_env
773 tcg_dus = tcg_dus tcg_env
774 `plusDU` usesOnly (unitFV main_name)
775 -- Record the use of 'main', so that we don't
776 -- complain about it being defined but not used
780 mod = tcg_mod tcg_env
782 complain_no_main | ghcLink dflags == LinkInMemory = return ()
783 | otherwise = failWithTc noMainMsg
784 -- In interactive mode, don't worry about the absence of 'main'
785 -- In other modes, fail altogether, so that we don't go on
786 -- and complain a second time when processing the export list.
788 mainCtxt = ptext SLIT("When checking the type of the main function") <+> quotes (ppr main_fn)
789 noMainMsg = ptext SLIT("The main function") <+> quotes (ppr main_fn)
790 <+> ptext SLIT("is not defined in module") <+> quotes (ppr main_mod)
795 The function that the RTS invokes is always :Main.main, which we call
796 root_main_id. (Because GHC allows the user to have a module not
797 called Main as the main module, we can't rely on the main function
798 being called "Main.main". That's why root_main_id has a fixed module
801 This is unusual: it's a LocalId whose Name has a Module from another
802 module. Tiresomely, we must filter it out again in MkIface, les we
803 get two defns for 'main' in the interface file!
806 %*********************************************************
810 %*********************************************************
814 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
815 setInteractiveContext hsc_env icxt thing_inside
817 -- Initialise the tcg_inst_env with instances
818 -- from all home modules. This mimics the more selective
819 -- call to hptInstances in tcRnModule
820 dfuns = hptInstances hsc_env (\mod -> True)
822 updGblEnv (\env -> env {
823 tcg_rdr_env = ic_rn_gbl_env icxt,
824 tcg_type_env = ic_type_env icxt,
825 tcg_inst_env = extendInstEnvList (tcg_inst_env env) dfuns }) $
827 updLclEnv (\env -> env { tcl_rdr = ic_rn_local_env icxt }) $
829 do { traceTc (text "setIC" <+> ppr (ic_type_env icxt))
836 -> InteractiveContext
838 -> IO (Maybe (InteractiveContext, [Name], LHsExpr Id))
839 -- The returned [Name] is the same as the input except for
840 -- ExprStmt, in which case the returned [Name] is [itName]
842 -- The returned TypecheckedHsExpr is of type IO [ () ],
843 -- a list of the bound values, coerced to ().
845 tcRnStmt hsc_env ictxt rdr_stmt
846 = initTcPrintErrors hsc_env iNTERACTIVE $
847 setInteractiveContext hsc_env ictxt $ do {
849 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
850 (([rn_stmt], _), fvs) <- rnStmts DoExpr [rdr_stmt] (return ((), emptyFVs)) ;
851 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
854 -- The real work is done here
855 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
856 zonked_expr <- zonkTopLExpr tc_expr ;
857 zonked_ids <- zonkTopBndrs bound_ids ;
859 -- None of the Ids should be of unboxed type, because we
860 -- cast them all to HValues in the end!
861 mappM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
863 traceTc (text "tcs 1") ;
864 let { -- (a) Make all the bound ids "global" ids, now that
865 -- they're notionally top-level bindings. This is
866 -- important: otherwise when we come to compile an expression
867 -- using these ids later, the byte code generator will consider
868 -- the occurrences to be free rather than global.
870 -- (b) Tidy their types; this is important, because :info may
871 -- ask to look at them, and :info expects the things it looks
872 -- up to have tidy types
873 global_ids = map globaliseAndTidy zonked_ids ;
875 -- Update the interactive context
876 rn_env = ic_rn_local_env ictxt ;
877 type_env = ic_type_env ictxt ;
879 bound_names = map idName global_ids ;
880 new_rn_env = extendLocalRdrEnv rn_env bound_names ;
882 {- ---------------------------------------------
883 At one stage I removed any shadowed bindings from the type_env;
884 they are inaccessible but might, I suppose, cause a space leak if we leave them there.
885 However, with Template Haskell they aren't necessarily inaccessible. Consider this
887 Prelude> let f n = n * 2 :: Int
888 Prelude> fName <- runQ [| f |]
889 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
891 Prelude> let f n = n * 3 :: Int
892 Prelude> $(return $ AppE fName (LitE (IntegerL 7)))
893 In the last line we use 'fName', which resolves to the *first* 'f'
894 in scope. If we delete it from the type env, GHCi crashes because
895 it doesn't expect that.
897 Hence this code is commented out
899 shadowed = [ n | name <- bound_names,
900 let rdr_name = mkRdrUnqual (nameOccName name),
901 Just n <- [lookupLocalRdrEnv rn_env rdr_name] ] ;
902 filtered_type_env = delListFromNameEnv type_env shadowed ;
903 -------------------------------------------------- -}
905 new_type_env = extendTypeEnvWithIds type_env global_ids ;
906 new_ic = ictxt { ic_rn_local_env = new_rn_env,
907 ic_type_env = new_type_env }
910 dumpOptTcRn Opt_D_dump_tc
911 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
912 text "Typechecked expr" <+> ppr zonked_expr]) ;
914 returnM (new_ic, bound_names, zonked_expr)
917 bad_unboxed id = addErr (sep [ptext SLIT("GHCi can't bind a variable of unlifted type:"),
918 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
920 globaliseAndTidy :: Id -> Id
922 -- Give the Id a Global Name, and tidy its type
923 = Id.setIdType (globaliseId VanillaGlobal id) tidy_type
925 tidy_type = tidyTopType (idType id)
928 Here is the grand plan, implemented in tcUserStmt
930 What you type The IO [HValue] that hscStmt returns
931 ------------- ------------------------------------
932 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
935 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
938 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
939 [NB: result not printed] bindings: [it]
941 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
942 result showable) bindings: [it]
944 expr (of non-IO type,
945 result not showable) ==> error
949 ---------------------------
950 type PlanResult = ([Id], LHsExpr Id)
951 type Plan = TcM PlanResult
953 runPlans :: [Plan] -> TcM PlanResult
954 -- Try the plans in order. If one fails (by raising an exn), try the next.
955 -- If one succeeds, take it.
956 runPlans [] = panic "runPlans"
958 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
961 mkPlan :: LStmt Name -> TcM PlanResult
962 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
963 = do { uniq <- newUnique -- is treated very specially
964 ; let fresh_it = itName uniq
965 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
966 matches = [mkMatch [] expr emptyLocalBinds]
967 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
968 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
969 (HsVar bindIOName) noSyntaxExpr
970 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
971 (HsVar thenIOName) placeHolderType
974 -- [it <- e; print it] but not if it::()
976 -- [let it = e; print it]
977 ; runPlans [ -- Plan A
978 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
979 ; it_ty <- zonkTcType (idType it_id)
980 ; ifM (isUnitTy it_ty) failM
983 -- Plan B; a naked bind statment
984 tcGhciStmts [bind_stmt],
986 -- Plan C; check that the let-binding is typeable all by itself.
987 -- If not, fail; if so, try to print it.
988 -- The two-step process avoids getting two errors: one from
989 -- the expression itself, and one from the 'print it' part
990 -- This two-step story is very clunky, alas
991 do { checkNoErrs (tcGhciStmts [let_stmt])
992 --- checkNoErrs defeats the error recovery of let-bindings
993 ; tcGhciStmts [let_stmt, print_it] }
996 mkPlan stmt@(L loc (BindStmt {}))
997 | [L _ v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
998 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
999 (HsVar thenIOName) placeHolderType
1001 ; print_bind_result <- doptM Opt_PrintBindResult
1002 ; let print_plan = do
1003 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
1004 ; v_ty <- zonkTcType (idType v_id)
1005 ; ifM (isUnitTy v_ty || not (isTauTy v_ty)) failM
1009 -- [stmt; print v] but not if v::()
1011 ; runPlans ((if print_bind_result then [print_plan] else []) ++
1012 [tcGhciStmts [stmt]])
1016 = tcGhciStmts [stmt]
1018 ---------------------------
1019 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1021 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1022 ret_id <- tcLookupId returnIOName ; -- return @ IO
1024 io_ty = mkTyConApp ioTyCon [] ;
1025 ret_ty = mkListTy unitTy ;
1026 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1027 tc_io_stmts stmts = tcStmts DoExpr (tcDoStmt io_ty) stmts
1028 (emptyRefinement, io_ret_ty) ;
1030 names = map unLoc (collectLStmtsBinders stmts) ;
1032 -- mk_return builds the expression
1033 -- returnIO @ [()] [coerce () x, .., coerce () z]
1035 -- Despite the inconvenience of building the type applications etc,
1036 -- this *has* to be done in type-annotated post-typecheck form
1037 -- because we are going to return a list of *polymorphic* values
1038 -- coerced to type (). If we built a *source* stmt
1039 -- return [coerce x, ..., coerce z]
1040 -- then the type checker would instantiate x..z, and we wouldn't
1041 -- get their *polymorphic* values. (And we'd get ambiguity errs
1042 -- if they were overloaded, since they aren't applied to anything.)
1043 mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty])
1044 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1045 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1049 -- OK, we're ready to typecheck the stmts
1050 traceTc (text "tcs 2") ;
1051 ((tc_stmts, ids), lie) <- getLIE $ tc_io_stmts stmts $ \ _ ->
1052 mappM tcLookupId names ;
1053 -- Look up the names right in the middle,
1054 -- where they will all be in scope
1056 -- Simplify the context
1057 const_binds <- checkNoErrs (tcSimplifyInteractive lie) ;
1058 -- checkNoErrs ensures that the plan fails if context redn fails
1060 return (ids, mkHsDictLet const_binds $
1061 noLoc (HsDo DoExpr tc_stmts (mk_return ids) io_ret_ty))
1066 tcRnExpr just finds the type of an expression
1070 -> InteractiveContext
1073 tcRnExpr hsc_env ictxt rdr_expr
1074 = initTcPrintErrors hsc_env iNTERACTIVE $
1075 setInteractiveContext hsc_env ictxt $ do {
1077 (rn_expr, fvs) <- rnLExpr rdr_expr ;
1080 -- Now typecheck the expression;
1081 -- it might have a rank-2 type (e.g. :t runST)
1082 ((tc_expr, res_ty), lie) <- getLIE (tcInferRho rn_expr) ;
1083 ((qtvs, dict_insts, _), lie_top) <- getLIE (tcSimplifyInfer smpl_doc (tyVarsOfType res_ty) lie) ;
1084 tcSimplifyInteractive lie_top ;
1086 let { all_expr_ty = mkForAllTys qtvs $
1087 mkFunTys (map (idType . instToId) dict_insts) $
1089 zonkTcType all_expr_ty
1092 smpl_doc = ptext SLIT("main expression")
1095 tcRnType just finds the kind of a type
1099 -> InteractiveContext
1102 tcRnType hsc_env ictxt rdr_type
1103 = initTcPrintErrors hsc_env iNTERACTIVE $
1104 setInteractiveContext hsc_env ictxt $ do {
1106 rn_type <- rnLHsType doc rdr_type ;
1109 -- Now kind-check the type
1110 (ty', kind) <- kcHsType rn_type ;
1114 doc = ptext SLIT("In GHCi input")
1120 %************************************************************************
1122 More GHCi stuff, to do with browsing and getting info
1124 %************************************************************************
1128 -- ASSUMES that the module is either in the HomePackageTable or is
1129 -- a package module with an interface on disk. If neither of these is
1130 -- true, then the result will be an error indicating the interface
1131 -- could not be found.
1132 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe [AvailInfo])
1133 getModuleExports hsc_env mod
1136 checkMods = ic_toplev_scope ic ++ ic_exports ic
1138 initTc hsc_env HsSrcFile False iNTERACTIVE (tcGetModuleExports mod checkMods)
1140 -- Get the export avail info and also load all orphan and family-instance
1141 -- modules. Finally, check that the family instances of all modules in the
1142 -- interactive context are consistent (these modules are in the second
1144 tcGetModuleExports :: Module -> [Module] -> TcM [AvailInfo]
1145 tcGetModuleExports mod directlyImpMods
1146 = do { let doc = ptext SLIT("context for compiling statements")
1147 ; iface <- initIfaceTcRn $ loadSysInterface doc mod
1149 -- Load any orphan-module and family instance-module
1150 -- interfaces, so their instances are visible.
1151 ; loadOrphanModules (dep_orphs (mi_deps iface)) False
1152 ; loadOrphanModules (dep_finsts (mi_deps iface)) True
1154 -- Check that the family instances of all directly loaded
1155 -- modules are consistent.
1156 ; checkFamInstConsistency (dep_finsts (mi_deps iface)) directlyImpMods
1158 ; ifaceExportNames (mi_exports iface)
1161 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Maybe [Name])
1162 tcRnLookupRdrName hsc_env rdr_name
1163 = initTcPrintErrors hsc_env iNTERACTIVE $
1164 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1165 lookup_rdr_name rdr_name
1167 lookup_rdr_name rdr_name = do {
1168 -- If the identifier is a constructor (begins with an
1169 -- upper-case letter), then we need to consider both
1170 -- constructor and type class identifiers.
1171 let { rdr_names = dataTcOccs rdr_name } ;
1173 -- results :: [Either Messages Name]
1174 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1176 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1177 -- The successful lookups will be (Just name)
1178 let { (warns_s, good_names) = unzip [ (msgs, name)
1179 | (msgs, Just name) <- results] ;
1180 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1182 -- Fail if nothing good happened, else add warnings
1183 if null good_names then
1184 -- No lookup succeeded, so
1185 -- pick the first error message and report it
1186 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1187 -- while the other is "X is not in scope",
1188 -- we definitely want the former; but we might pick the latter
1189 do { addMessages (head errs_s) ; failM }
1190 else -- Add deprecation warnings
1191 mapM_ addMessages warns_s ;
1196 tcRnRecoverDataCon :: HscEnv -> a -> IO (Maybe DataCon)
1197 tcRnRecoverDataCon hsc_env a
1198 = initTcPrintErrors hsc_env iNTERACTIVE $
1199 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1200 do name <- recoverDataCon a
1201 tcLookupDataCon name
1203 tcRnLookupName :: HscEnv -> Name -> IO (Maybe TyThing)
1204 tcRnLookupName hsc_env name
1205 = initTcPrintErrors hsc_env iNTERACTIVE $
1206 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1210 tcRnGetInfo :: HscEnv
1212 -> IO (Maybe (TyThing, Fixity, [Instance]))
1214 -- Used to implemnent :info in GHCi
1216 -- Look up a RdrName and return all the TyThings it might be
1217 -- A capitalised RdrName is given to us in the DataName namespace,
1218 -- but we want to treat it as *both* a data constructor
1219 -- *and* as a type or class constructor;
1220 -- hence the call to dataTcOccs, and we return up to two results
1221 tcRnGetInfo hsc_env name
1222 = initTcPrintErrors hsc_env iNTERACTIVE $
1223 let ictxt = hsc_IC hsc_env in
1224 setInteractiveContext hsc_env ictxt $ do
1226 -- Load the interface for all unqualified types and classes
1227 -- That way we will find all the instance declarations
1228 -- (Packages have not orphan modules, and we assume that
1229 -- in the home package all relevant modules are loaded.)
1230 loadUnqualIfaces ictxt
1232 thing <- tcLookupGlobal name
1233 fixity <- lookupFixityRn name
1234 ispecs <- lookupInsts (icPrintUnqual ictxt) thing
1235 return (thing, fixity, ispecs)
1237 lookupInsts :: PrintUnqualified -> TyThing -> TcM [Instance]
1238 -- Filter the instances by the ones whose tycons (or clases resp)
1239 -- are in scope unqualified. Otherwise we list a whole lot too many!
1240 lookupInsts print_unqual (AClass cls)
1241 = do { inst_envs <- tcGetInstEnvs
1243 | ispec <- classInstances inst_envs cls
1244 , plausibleDFun print_unqual (instanceDFunId ispec) ] }
1246 lookupInsts print_unqual (ATyCon tc)
1247 = do { eps <- getEps -- Load all instances for all classes that are
1248 -- in the type environment (which are all the ones
1249 -- we've seen in any interface file so far)
1250 ; (pkg_ie, home_ie) <- tcGetInstEnvs -- Search all
1252 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1253 , let dfun = instanceDFunId ispec
1255 , plausibleDFun print_unqual dfun ] }
1257 relevant df = tc_name `elemNameSet` tyClsNamesOfDFunHead (idType df)
1258 tc_name = tyConName tc
1260 lookupInsts print_unqual other = return []
1262 plausibleDFun print_unqual dfun -- Dfun involving only names that print unqualified
1263 = all ok (nameSetToList (tyClsNamesOfType (idType dfun)))
1265 ok name | isBuiltInSyntax name = True
1266 | isExternalName name =
1267 isNothing $ fst print_unqual (nameModule name)
1271 loadUnqualIfaces :: InteractiveContext -> TcM ()
1272 -- Load the home module for everything that is in scope unqualified
1273 -- This is so that we can accurately report the instances for
1275 loadUnqualIfaces ictxt
1277 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1279 unqual_mods = [ nameModule name
1280 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1281 let name = gre_name gre,
1282 not (isInternalName name),
1283 isTcOcc (nameOccName name), -- Types and classes only
1284 unQualOK gre ] -- In scope unqualified
1285 doc = ptext SLIT("Need interface for module whose export(s) are in scope unqualified")
1289 %************************************************************************
1293 %************************************************************************
1296 rnDump :: SDoc -> TcRn ()
1297 -- Dump, with a banner, if -ddump-rn
1298 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1300 tcDump :: TcGblEnv -> TcRn ()
1302 = do { dflags <- getDOpts ;
1304 -- Dump short output if -ddump-types or -ddump-tc
1305 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1306 (dumpTcRn short_dump) ;
1308 -- Dump bindings if -ddump-tc
1309 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1312 short_dump = pprTcGblEnv env
1313 full_dump = pprLHsBinds (tcg_binds env)
1314 -- NB: foreign x-d's have undefined's in their types;
1315 -- hence can't show the tc_fords
1318 = do { dflags <- getDOpts ;
1319 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1320 (dumpTcRn (pprModGuts mod_guts)) ;
1322 -- Dump bindings if -ddump-tc
1323 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1325 full_dump = pprCoreBindings (mg_binds mod_guts)
1327 -- It's unpleasant having both pprModGuts and pprModDetails here
1328 pprTcGblEnv :: TcGblEnv -> SDoc
1329 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1331 tcg_fam_insts = fam_insts,
1333 tcg_imports = imports })
1334 = vcat [ ppr_types insts type_env
1335 , ppr_tycons fam_insts type_env
1337 , ppr_fam_insts fam_insts
1338 , vcat (map ppr rules)
1339 , ppr_gen_tycons (typeEnvTyCons type_env)
1340 , ptext SLIT("Dependent modules:") <+> ppr (eltsUFM (imp_dep_mods imports))
1341 , ptext SLIT("Dependent packages:") <+> ppr (imp_dep_pkgs imports)]
1343 pprModGuts :: ModGuts -> SDoc
1344 pprModGuts (ModGuts { mg_types = type_env,
1346 = vcat [ ppr_types [] type_env,
1349 ppr_types :: [Instance] -> TypeEnv -> SDoc
1350 ppr_types insts type_env
1351 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1353 dfun_ids = map instanceDFunId insts
1354 ids = [id | id <- typeEnvIds type_env, want_sig id]
1355 want_sig id | opt_PprStyle_Debug = True
1356 | otherwise = isLocalId id &&
1357 isExternalName (idName id) &&
1358 not (id `elem` dfun_ids)
1359 -- isLocalId ignores data constructors, records selectors etc.
1360 -- The isExternalName ignores local dictionary and method bindings
1361 -- that the type checker has invented. Top-level user-defined things
1362 -- have External names.
1364 ppr_tycons :: [FamInst] -> TypeEnv -> SDoc
1365 ppr_tycons fam_insts type_env
1366 = text "TYPE CONSTRUCTORS" $$ nest 4 (ppr_tydecls tycons)
1368 fi_tycons = map famInstTyCon fam_insts
1369 tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
1370 want_tycon tycon | opt_PprStyle_Debug = True
1371 | otherwise = not (isImplicitTyCon tycon) &&
1372 isExternalName (tyConName tycon) &&
1373 not (tycon `elem` fi_tycons)
1375 ppr_insts :: [Instance] -> SDoc
1376 ppr_insts [] = empty
1377 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1379 ppr_fam_insts :: [FamInst] -> SDoc
1380 ppr_fam_insts [] = empty
1381 ppr_fam_insts fam_insts =
1382 text "FAMILY INSTANCES" $$ nest 2 (pprFamInsts fam_insts)
1384 ppr_sigs :: [Var] -> SDoc
1386 -- Print type signatures; sort by OccName
1387 = vcat (map ppr_sig (sortLe le_sig ids))
1389 le_sig id1 id2 = getOccName id1 <= getOccName id2
1390 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1392 ppr_tydecls :: [TyCon] -> SDoc
1394 -- Print type constructor info; sort by OccName
1395 = vcat (map ppr_tycon (sortLe le_sig tycons))
1397 le_sig tycon1 tycon2 = getOccName tycon1 <= getOccName tycon2
1399 | isCoercionTyCon tycon = ptext SLIT("coercion") <+> ppr tycon
1400 | otherwise = ppr (tyThingToIfaceDecl (ATyCon tycon))
1402 ppr_rules :: [CoreRule] -> SDoc
1403 ppr_rules [] = empty
1404 ppr_rules rs = vcat [ptext SLIT("{-# RULES"),
1405 nest 4 (pprRules rs),
1408 ppr_gen_tycons [] = empty
1409 ppr_gen_tycons tcs = vcat [ptext SLIT("Tycons with generics:"),
1410 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]