2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[TcModule]{Typechecking a whole module}
9 tcRnStmt, tcRnExpr, tcRnType,
20 #include "HsVersions.h"
24 import {-# SOURCE #-} TcSplice ( tcSpliceDecls )
27 import DynFlags ( DynFlag(..), DynFlags(..), dopt, GhcMode(..) )
28 import StaticFlags ( opt_PprStyle_Debug )
29 import HsSyn ( HsModule(..), HsExtCore(..), HsGroup(..), LHsDecl,
30 SpliceDecl(..), HsBind(..), LHsBinds,
31 emptyRdrGroup, emptyRnGroup, appendGroups, plusHsValBinds,
32 nlHsApp, nlHsVar, pprLHsBinds, HaddockModInfo(..) )
33 import RdrHsSyn ( findSplice )
35 import PrelNames ( runMainIOName, rootMainKey, rOOT_MAIN, mAIN,
37 import RdrName ( RdrName, mkRdrUnqual, emptyGlobalRdrEnv )
38 import TcHsSyn ( zonkTopDecls )
39 import TcExpr ( tcInferRho )
41 import TcType ( tidyTopType, tcEqType )
42 import Inst ( showLIE )
43 import InstEnv ( extendInstEnvList, Instance, pprInstances, instanceDFunId )
44 import TcBinds ( tcTopBinds, tcHsBootSigs )
45 import TcDefaults ( tcDefaults )
46 import TcEnv ( tcExtendGlobalValEnv, iDFunId )
47 import TcRules ( tcRules )
48 import TcForeign ( tcForeignImports, tcForeignExports )
49 import TcInstDcls ( tcInstDecls1, tcInstDecls2 )
50 import TcIface ( tcExtCoreBindings, tcHiBootIface )
51 import MkIface ( tyThingToIfaceDecl )
52 import IfaceSyn ( checkBootDecl, IfaceExtName(..) )
53 import TcSimplify ( tcSimplifyTop )
54 import TcTyClsDecls ( tcTyAndClassDecls )
55 import LoadIface ( loadOrphanModules )
56 import RnNames ( importsFromLocalDecls, rnImports, rnExports,
57 mkRdrEnvAndImports, mkExportNameSet,
58 reportUnusedNames, reportDeprecations )
59 import RnEnv ( lookupSrcOcc_maybe )
60 import RnSource ( rnSrcDecls, rnTyClDecls, checkModDeprec )
61 import RnHsDoc ( rnMbHsDoc )
62 import PprCore ( pprRules, pprCoreBindings )
63 import CoreSyn ( CoreRule, bindersOfBinds )
64 import ErrUtils ( Messages, mkDumpDoc, showPass )
65 import Id ( Id, mkExportedLocalId, isLocalId, idName, idType )
68 import UniqFM ( elemUFM, eltsUFM )
69 import OccName ( mkVarOccFS, plusOccEnv )
70 import Name ( Name, NamedThing(..), isExternalName, getSrcLoc, isWiredInName,
71 nameModule, nameOccName, isImplicitName, mkExternalName )
73 import TyCon ( tyConHasGenerics )
74 import SrcLoc ( srcLocSpan, Located(..), noLoc )
75 import DriverPhases ( HscSource(..), isHsBoot )
76 import HscTypes ( ModGuts(..), ModDetails(..), emptyModDetails,
77 HscEnv(..), ExternalPackageState(..),
78 IsBootInterface, noDependencies,
79 Deprecs( NoDeprecs ), plusDeprecs,
80 ForeignStubs(NoStubs),
81 TypeEnv, lookupTypeEnv, hptInstances,
82 extendTypeEnvWithIds, typeEnvIds, typeEnvTyCons, typeEnvElts,
88 import HsSyn ( HsStmtContext(..), Stmt(..), HsExpr(..),
89 HsLocalBinds(..), HsValBinds(..),
90 LStmt, LHsExpr, LHsType, mkMatch, emptyLocalBinds,
91 collectLStmtsBinders, collectLStmtBinders, nlVarPat,
92 mkFunBind, placeHolderType, noSyntaxExpr, nlHsTyApp )
93 import RdrName ( GlobalRdrElt(..), globalRdrEnvElts,
94 unQualOK, lookupLocalRdrEnv, extendLocalRdrEnv )
95 import RnSource ( addTcgDUs )
96 import TcHsSyn ( mkHsDictLet, zonkTopLExpr, zonkTopBndrs )
97 import TcHsType ( kcHsType )
98 import TcMType ( zonkTcType, zonkQuantifiedTyVar )
99 import TcMatches ( tcStmts, tcDoStmt )
100 import TcSimplify ( tcSimplifyInteractive, tcSimplifyInfer )
101 import TcGadt ( emptyRefinement )
102 import TcType ( Type, mkForAllTys, mkFunTys, mkTyConApp, tyVarsOfType, isTauTy,
103 isUnLiftedType, tyClsNamesOfDFunHead, tyClsNamesOfType, isUnitTy )
104 import TcEnv ( tcLookupTyCon, tcLookupId, tcLookupGlobal )
105 import TypeRep ( TyThing(..) )
106 import RnTypes ( rnLHsType )
107 import Inst ( tcGetInstEnvs )
108 import InstEnv ( classInstances, instEnvElts )
109 import RnExpr ( rnStmts, rnLExpr )
110 import LoadIface ( loadSysInterface )
111 import IfaceEnv ( ifaceExportNames )
112 import RnEnv ( lookupOccRn, dataTcOccs, lookupFixityRn )
113 import Id ( setIdType )
114 import MkId ( unsafeCoerceId )
115 import TyCon ( tyConName )
116 import TysWiredIn ( mkListTy, unitTy )
117 import IdInfo ( GlobalIdDetails(..) )
118 import {- Kind parts of -} Type ( Kind )
119 import Var ( globaliseId )
120 import Name ( isBuiltInSyntax, isInternalName )
121 import OccName ( isTcOcc )
122 import NameEnv ( delListFromNameEnv )
123 import PrelNames ( iNTERACTIVE, ioTyConName, printName, itName,
124 bindIOName, thenIOName, returnIOName )
125 import HscTypes ( InteractiveContext(..),
126 ModIface(..), icPrintUnqual,
128 import BasicTypes ( Fixity, RecFlag(..) )
129 import SrcLoc ( unLoc )
130 import Data.Maybe ( isNothing )
133 import FastString ( mkFastString )
134 import Util ( sortLe )
135 import Bag ( unionBags, snocBag, emptyBag, unitBag, unionManyBags )
137 import Data.Maybe ( isJust )
142 %************************************************************************
144 Typecheck and rename a module
146 %************************************************************************
152 -> Bool -- True <=> save renamed syntax
153 -> Located (HsModule RdrName)
154 -> IO (Messages, Maybe TcGblEnv)
156 tcRnModule hsc_env hsc_src save_rn_syntax
157 (L loc (HsModule maybe_mod export_ies
158 import_decls local_decls mod_deprec _ module_info maybe_doc))
159 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
161 let { this_pkg = thisPackage (hsc_dflags hsc_env) ;
162 this_mod = case maybe_mod of
163 Nothing -> mAIN -- 'module M where' is omitted
164 Just (L _ mod) -> mkModule this_pkg mod } ;
167 initTc hsc_env hsc_src this_mod $
170 -- Deal with imports;
171 rn_imports <- rnImports import_decls ;
172 (rdr_env, imports) <- mkRdrEnvAndImports rn_imports ;
174 let { dep_mods :: ModuleNameEnv (ModuleName, IsBootInterface)
175 ; dep_mods = imp_dep_mods imports
177 -- We want instance declarations from all home-package
178 -- modules below this one, including boot modules, except
179 -- ourselves. The 'except ourselves' is so that we don't
180 -- get the instances from this module's hs-boot file
181 ; want_instances :: ModuleName -> Bool
182 ; want_instances mod = mod `elemUFM` dep_mods
183 && mod /= moduleName this_mod
184 ; home_insts = hptInstances hsc_env want_instances
187 -- Record boot-file info in the EPS, so that it's
188 -- visible to loadHiBootInterface in tcRnSrcDecls,
189 -- and any other incrementally-performed imports
190 updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
192 -- Update the gbl env
194 gbl { tcg_rdr_env = plusOccEnv (tcg_rdr_env gbl) rdr_env,
195 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
196 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
197 tcg_rn_imports = if save_rn_syntax then
201 tcg_rn_decls = if save_rn_syntax then
207 traceRn (text "rn1" <+> ppr (imp_dep_mods imports)) ;
208 -- Fail if there are any errors so far
209 -- The error printing (if needed) takes advantage
210 -- of the tcg_env we have now set
213 -- Load any orphan-module interfaces, so that
214 -- their rules and instance decls will be found
215 loadOrphanModules (imp_orphs imports) ;
217 traceRn (text "rn1a") ;
218 -- Rename and type check the declarations
219 tcg_env <- if isHsBoot hsc_src then
220 tcRnHsBootDecls local_decls
222 tcRnSrcDecls local_decls ;
223 setGblEnv tcg_env $ do {
225 traceRn (text "rn3") ;
227 -- Report the use of any deprecated things
228 -- We do this before processsing the export list so
229 -- that we don't bleat about re-exporting a deprecated
230 -- thing (especially via 'module Foo' export item)
231 -- Only uses in the body of the module are complained about
232 reportDeprecations (hsc_dflags hsc_env) tcg_env ;
234 -- Process the export list
235 rn_exports <- rnExports export_ies ;
237 -- Rename the Haddock documentation header
238 rn_module_doc <- rnMbHsDoc maybe_doc ;
240 -- Rename the Haddock module info
241 rn_description <- rnMbHsDoc (hmi_description module_info) ;
242 let { rn_module_info = module_info { hmi_description = rn_description } } ;
244 let { liftM2' fn a b = do a' <- a; b' <- b; return (fn a' b') } ;
245 exports <- mkExportNameSet (isJust maybe_mod)
246 (liftM2' (,) rn_exports export_ies) ;
248 -- Check whether the entire module is deprecated
249 -- This happens only once per module
250 let { mod_deprecs = checkModDeprec mod_deprec } ;
252 -- Add exports and deprecations to envt
253 let { final_env = tcg_env { tcg_exports = exports,
254 tcg_rn_exports = if save_rn_syntax then
257 tcg_dus = tcg_dus tcg_env `plusDU` usesOnly exports,
258 tcg_deprecs = tcg_deprecs tcg_env `plusDeprecs`
260 tcg_doc = rn_module_doc,
261 tcg_hmi = rn_module_info
263 -- A module deprecation over-rides the earlier ones
266 -- Report unused names
267 reportUnusedNames export_ies final_env ;
269 -- Dump output and return
276 %************************************************************************
278 Type-checking external-core modules
280 %************************************************************************
283 tcRnExtCore :: HscEnv
285 -> IO (Messages, Maybe ModGuts)
286 -- Nothing => some error occurred
288 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
289 -- The decls are IfaceDecls; all names are original names
290 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
292 initTc hsc_env ExtCoreFile this_mod $ do {
294 let { ldecls = map noLoc decls } ;
296 -- Deal with the type declarations; first bring their stuff
297 -- into scope, then rname them, then type check them
298 tcg_env <- importsFromLocalDecls (mkFakeGroup ldecls) ;
300 setGblEnv tcg_env $ do {
302 rn_decls <- rnTyClDecls ldecls ;
305 -- Dump trace of renaming part
306 rnDump (ppr rn_decls) ;
308 -- Typecheck them all together so that
309 -- any mutually recursive types are done right
310 tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails rn_decls) ;
311 -- Make the new type env available to stuff slurped from interface files
313 setGblEnv tcg_env $ do {
315 -- Now the core bindings
316 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
320 bndrs = bindersOfBinds core_binds ;
321 my_exports = mkNameSet (map idName bndrs) ;
322 -- ToDo: export the data types also?
324 final_type_env = extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
326 mod_guts = ModGuts { mg_module = this_mod,
328 mg_usages = [], -- ToDo: compute usage
329 mg_dir_imps = [], -- ??
330 mg_deps = noDependencies, -- ??
331 mg_exports = my_exports,
332 mg_types = final_type_env,
333 mg_insts = tcg_insts tcg_env,
335 mg_binds = core_binds,
338 mg_rdr_env = emptyGlobalRdrEnv,
339 mg_fix_env = emptyFixityEnv,
340 mg_deprecs = NoDeprecs,
344 tcCoreDump mod_guts ;
349 mkFakeGroup decls -- Rather clumsy; lots of unused fields
350 = emptyRdrGroup { hs_tyclds = decls }
354 %************************************************************************
356 Type-checking the top level of a module
358 %************************************************************************
361 tcRnSrcDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
362 -- Returns the variables free in the decls
363 -- Reason: solely to report unused imports and bindings
365 = do { -- Load the hi-boot interface for this module, if any
366 -- We do this now so that the boot_names can be passed
367 -- to tcTyAndClassDecls, because the boot_names are
368 -- automatically considered to be loop breakers
370 boot_iface <- tcHiBootIface mod ;
372 -- Do all the declarations
373 (tc_envs, lie) <- getLIE (tc_rn_src_decls boot_iface decls) ;
375 -- tcSimplifyTop deals with constant or ambiguous InstIds.
376 -- How could there be ambiguous ones? They can only arise if a
377 -- top-level decl falls under the monomorphism
378 -- restriction, and no subsequent decl instantiates its
379 -- type. (Usually, ambiguous type variables are resolved
380 -- during the generalisation step.)
381 traceTc (text "Tc8") ;
382 inst_binds <- setEnvs tc_envs (tcSimplifyTop lie) ;
383 -- Setting the global env exposes the instances to tcSimplifyTop
384 -- Setting the local env exposes the local Ids to tcSimplifyTop,
385 -- so that we get better error messages (monomorphism restriction)
387 -- Backsubstitution. This must be done last.
388 -- Even tcSimplifyTop may do some unification.
389 traceTc (text "Tc9") ;
390 let { (tcg_env, _) = tc_envs ;
391 TcGblEnv { tcg_type_env = type_env, tcg_binds = binds,
392 tcg_rules = rules, tcg_fords = fords } = tcg_env } ;
394 (bind_ids, binds', fords', rules') <- zonkTopDecls (binds `unionBags` inst_binds)
397 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
398 ; tcg_env' = tcg_env { tcg_type_env = final_type_env,
401 tcg_fords = fords' } } ;
403 -- Make the new type env available to stuff slurped from interface files
404 writeMutVar (tcg_type_env_var tcg_env) final_type_env ;
406 -- Compare the hi-boot iface (if any) with the real thing
407 dfun_binds <- checkHiBootIface tcg_env' boot_iface ;
409 return (tcg_env' { tcg_binds = tcg_binds tcg_env' `unionBags` dfun_binds })
412 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
413 -- Loops around dealing with each top level inter-splice group
414 -- in turn, until it's dealt with the entire module
415 tc_rn_src_decls boot_details ds
416 = do { let { (first_group, group_tail) = findSplice ds } ;
417 -- If ds is [] we get ([], Nothing)
419 -- Type check the decls up to, but not including, the first splice
420 tc_envs@(tcg_env,tcl_env) <- tcRnGroup boot_details first_group ;
422 -- Bale out if errors; for example, error recovery when checking
423 -- the RHS of 'main' can mean that 'main' is not in the envt for
424 -- the subsequent checkMain test
429 -- If there is no splice, we're nearly done
431 Nothing -> do { -- Last thing: check for `main'
432 tcg_env <- checkMain ;
433 return (tcg_env, tcl_env)
436 -- If there's a splice, we must carry on
437 Just (SpliceDecl splice_expr, rest_ds) -> do {
439 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
442 -- Rename the splice expression, and get its supporting decls
443 (rn_splice_expr, splice_fvs) <- rnLExpr splice_expr ;
444 failIfErrsM ; -- Don't typecheck if renaming failed
445 rnDump (ppr rn_splice_expr) ;
447 -- Execute the splice
448 spliced_decls <- tcSpliceDecls rn_splice_expr ;
450 -- Glue them on the front of the remaining decls and loop
451 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
452 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
457 %************************************************************************
459 Compiling hs-boot source files, and
460 comparing the hi-boot interface with the real thing
462 %************************************************************************
465 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
466 tcRnHsBootDecls decls
467 = do { let { (first_group, group_tail) = findSplice decls }
470 Just stuff -> spliceInHsBootErr stuff
473 -- Rename the declarations
474 ; (tcg_env, rn_group) <- rnTopSrcDecls first_group
475 ; setGblEnv tcg_env $ do {
477 -- Todo: check no foreign decls, no rules, no default decls
479 -- Typecheck type/class decls
480 ; traceTc (text "Tc2")
481 ; let tycl_decls = hs_tyclds rn_group
482 ; tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails tycl_decls)
483 ; setGblEnv tcg_env $ do {
485 -- Typecheck instance decls
486 ; traceTc (text "Tc3")
487 ; (tcg_env, inst_infos, _binds)
488 <- tcInstDecls1 tycl_decls (hs_instds rn_group) (hs_derivds rn_group)
489 ; setGblEnv tcg_env $ do {
491 -- Typecheck value declarations
492 ; traceTc (text "Tc5")
493 ; val_ids <- tcHsBootSigs (hs_valds rn_group)
496 -- No simplification or zonking to do
497 ; traceTc (text "Tc7a")
498 ; gbl_env <- getGblEnv
500 -- Make the final type-env
501 -- Include the dfun_ids so that their type sigs get
502 -- are written into the interface file
503 ; let { type_env0 = tcg_type_env gbl_env
504 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
505 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
506 ; dfun_ids = map iDFunId inst_infos }
507 ; return (gbl_env { tcg_type_env = type_env2 })
510 spliceInHsBootErr (SpliceDecl (L loc _), _)
511 = addErrAt loc (ptext SLIT("Splices are not allowed in hs-boot files"))
514 Once we've typechecked the body of the module, we want to compare what
515 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
518 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM (LHsBinds Id)
519 -- Compare the hi-boot file for this module (if there is one)
520 -- with the type environment we've just come up with
521 -- In the common case where there is no hi-boot file, the list
522 -- of boot_names is empty.
524 -- The bindings we return give bindings for the dfuns defined in the
525 -- hs-boot file, such as $fbEqT = $fEqT
528 (TcGblEnv { tcg_insts = local_insts, tcg_type_env = local_type_env })
529 (ModDetails { md_insts = boot_insts, md_types = boot_type_env })
530 = do { traceTc (text "checkHiBootIface" <+> (ppr boot_type_env $$ ppr boot_insts)) ;
531 ; mapM_ check_one (typeEnvElts boot_type_env)
532 ; dfun_binds <- mapM check_inst boot_insts
533 ; return (unionManyBags dfun_binds) }
538 | Just real_thing <- lookupTypeEnv local_type_env name
539 = do { let boot_decl = tyThingToIfaceDecl ext_nm boot_thing
540 real_decl = tyThingToIfaceDecl ext_nm real_thing
541 ; checkTc (checkBootDecl boot_decl real_decl)
542 (bootMisMatch boot_thing boot_decl real_decl) }
543 -- The easiest way to check compatibility is to convert to
544 -- iface syntax, where we already have good comparison functions
546 = addErrTc (missingBootThing boot_thing)
548 name = getName boot_thing
550 ext_nm name = ExtPkg (nameModule name) (nameOccName name)
551 -- Just enough to compare; no versions etc needed
553 no_check name = isWiredInName name -- No checking for wired-in names. In particular,
554 -- 'error' is handled by a rather gross hack
555 -- (see comments in GHC.Err.hs-boot)
556 || name `elem` dfun_names
557 || isImplicitName name -- Has a parent, which we'll check
559 dfun_names = map getName boot_insts
562 = case [dfun | inst <- local_insts,
563 let dfun = instanceDFunId inst,
564 idType dfun `tcEqType` boot_inst_ty ] of
565 [] -> do { addErrTc (instMisMatch boot_inst); return emptyBag }
566 (dfun:_) -> return (unitBag $ noLoc $ VarBind local_boot_dfun (nlHsVar dfun))
568 boot_dfun = instanceDFunId boot_inst
569 boot_inst_ty = idType boot_dfun
570 local_boot_dfun = mkExportedLocalId (idName boot_dfun) boot_inst_ty
573 missingBootThing thing
574 = ppr thing <+> ptext SLIT("is defined in the hs-boot file, but not in the module")
575 bootMisMatch thing boot_decl real_decl
576 = vcat [ppr thing <+> ptext SLIT("has conflicting definitions in the module and its hs-boot file"),
577 ptext SLIT("Decl") <+> ppr real_decl,
578 ptext SLIT("Boot file:") <+> ppr boot_decl]
581 2 (ptext SLIT("is defined in the hs-boot file, but not in the module"))
585 %************************************************************************
587 Type-checking the top level of a module
589 %************************************************************************
591 tcRnGroup takes a bunch of top-level source-code declarations, and
593 * gets supporting declarations from interface files
596 * and augments the TcGblEnv with the results
598 In Template Haskell it may be called repeatedly for each group of
599 declarations. It expects there to be an incoming TcGblEnv in the
600 monad; it augments it and returns the new TcGblEnv.
603 tcRnGroup :: ModDetails -> HsGroup RdrName -> TcM (TcGblEnv, TcLclEnv)
604 -- Returns the variables free in the decls, for unused-binding reporting
605 tcRnGroup boot_details decls
606 = do { -- Rename the declarations
607 (tcg_env, rn_decls) <- rnTopSrcDecls decls ;
608 setGblEnv tcg_env $ do {
610 -- Typecheck the declarations
611 tcTopSrcDecls boot_details rn_decls
614 ------------------------------------------------
615 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
617 = do { -- Bring top level binders into scope
618 tcg_env <- importsFromLocalDecls group ;
619 setGblEnv tcg_env $ do {
621 failIfErrsM ; -- No point in continuing if (say) we have duplicate declarations
623 -- Rename the source decls
624 (tcg_env, rn_decls) <- rnSrcDecls group ;
627 -- save the renamed syntax, if we want it
629 | Just grp <- tcg_rn_decls tcg_env
630 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
634 -- Dump trace of renaming part
635 rnDump (ppr rn_decls) ;
637 return (tcg_env', rn_decls)
640 ------------------------------------------------
641 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
642 tcTopSrcDecls boot_details
643 (HsGroup { hs_tyclds = tycl_decls,
644 hs_instds = inst_decls,
645 hs_derivds = deriv_decls,
646 hs_fords = foreign_decls,
647 hs_defds = default_decls,
648 hs_ruleds = rule_decls,
649 hs_valds = val_binds })
650 = do { -- Type-check the type and class decls, and all imported decls
651 -- The latter come in via tycl_decls
652 traceTc (text "Tc2") ;
654 tcg_env <- checkNoErrs (tcTyAndClassDecls boot_details tycl_decls) ;
655 -- tcTyAndClassDecls recovers internally, but if anything gave rise to
656 -- an error we'd better stop now, to avoid a cascade
658 -- Make these type and class decls available to stuff slurped from interface files
659 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
662 setGblEnv tcg_env $ do {
663 -- Source-language instances, including derivings,
664 -- and import the supporting declarations
665 traceTc (text "Tc3") ;
666 (tcg_env, inst_infos, deriv_binds)
667 <- tcInstDecls1 tycl_decls inst_decls deriv_decls;
668 setGblEnv tcg_env $ do {
670 -- Foreign import declarations next. No zonking necessary
671 -- here; we can tuck them straight into the global environment.
672 traceTc (text "Tc4") ;
673 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
674 tcExtendGlobalValEnv fi_ids $ do {
676 -- Default declarations
677 traceTc (text "Tc4a") ;
678 default_tys <- tcDefaults default_decls ;
679 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
681 -- Value declarations next
682 -- We also typecheck any extra binds that came out
683 -- of the "deriving" process (deriv_binds)
684 traceTc (text "Tc5") ;
685 (tc_val_binds, tcl_env) <- tcTopBinds (val_binds `plusHsValBinds` deriv_binds) ;
686 setLclTypeEnv tcl_env $ do {
688 -- Second pass over class and instance declarations,
689 traceTc (text "Tc6") ;
690 (inst_binds, tcl_env) <- tcInstDecls2 tycl_decls inst_infos ;
691 showLIE (text "after instDecls2") ;
694 -- They need to be zonked, so we return them
695 traceTc (text "Tc7") ;
696 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
699 rules <- tcRules rule_decls ;
702 traceTc (text "Tc7a") ;
703 tcg_env <- getGblEnv ;
704 let { all_binds = tc_val_binds `unionBags`
705 inst_binds `unionBags`
708 -- Extend the GblEnv with the (as yet un-zonked)
709 -- bindings, rules, foreign decls
710 tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds,
711 tcg_rules = tcg_rules tcg_env ++ rules,
712 tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
713 return (tcg_env', tcl_env)
718 %************************************************************************
722 %************************************************************************
725 checkMain :: TcM TcGblEnv
726 -- If we are in module Main, check that 'main' is defined.
728 = do { ghc_mode <- getGhcMode ;
729 tcg_env <- getGblEnv ;
731 let { main_mod = mainModIs dflags ;
732 main_fn = case mainFunIs dflags of {
733 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn)) ;
734 Nothing -> main_RDR_Unqual } } ;
736 check_main ghc_mode tcg_env main_mod main_fn
740 check_main ghc_mode tcg_env main_mod main_fn
742 = traceTc (text "checkMain not" <+> ppr main_mod <+> ppr mod) >>
746 = addErrCtxt mainCtxt $
747 do { mb_main <- lookupSrcOcc_maybe main_fn
748 -- Check that 'main' is in scope
749 -- It might be imported from another module!
751 Nothing -> do { traceTc (text "checkMain fail" <+> ppr main_mod <+> ppr main_fn)
755 { traceTc (text "checkMain found" <+> ppr main_mod <+> ppr main_fn)
756 ; let { rhs = nlHsApp (nlHsVar runMainIOName) (nlHsVar main_name) }
757 -- :Main.main :: IO () = runMainIO main
759 ; (main_expr, ty) <- setSrcSpan (srcLocSpan (getSrcLoc main_name)) $
762 -- The function that the RTS invokes is always :Main.main,
763 -- which we call root_main_id.
764 -- (Because GHC allows the user to have a module not called
765 -- Main as the main module, we can't rely on the main function
766 -- being called "Main.main". That's why root_main_id has a fixed
768 -- We also make root_main_id an implicit Id, by making main_name
769 -- its parent (hence (Just main_name)). That has the effect
770 -- of preventing its type and unfolding from getting out into
771 -- the interface file. Otherwise we can end up with two defns
772 -- for 'main' in the interface file!
774 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
775 (mkVarOccFS FSLIT("main"))
776 (Just main_name) (getSrcLoc main_name)
777 ; root_main_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
791 complain_no_main | ghc_mode == Interactive = return ()
792 | otherwise = failWithTc noMainMsg
793 -- In interactive mode, don't worry about the absence of 'main'
794 -- In other modes, fail altogether, so that we don't go on
795 -- and complain a second time when processing the export list.
797 mainCtxt = ptext SLIT("When checking the type of the main function") <+> quotes (ppr main_fn)
798 noMainMsg = ptext SLIT("The main function") <+> quotes (ppr main_fn)
799 <+> ptext SLIT("is not defined in module") <+> quotes (ppr main_mod)
802 %*********************************************************
806 %*********************************************************
810 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
811 setInteractiveContext hsc_env icxt thing_inside
813 -- Initialise the tcg_inst_env with instances
814 -- from all home modules. This mimics the more selective
815 -- call to hptInstances in tcRnModule
816 dfuns = hptInstances hsc_env (\mod -> True)
818 updGblEnv (\env -> env {
819 tcg_rdr_env = ic_rn_gbl_env icxt,
820 tcg_type_env = ic_type_env icxt,
821 tcg_inst_env = extendInstEnvList (tcg_inst_env env) dfuns }) $
823 updLclEnv (\env -> env { tcl_rdr = ic_rn_local_env icxt }) $
825 do { traceTc (text "setIC" <+> ppr (ic_type_env icxt))
832 -> InteractiveContext
834 -> IO (Maybe (InteractiveContext, [Name], LHsExpr Id))
835 -- The returned [Name] is the same as the input except for
836 -- ExprStmt, in which case the returned [Name] is [itName]
838 -- The returned TypecheckedHsExpr is of type IO [ () ],
839 -- a list of the bound values, coerced to ().
841 tcRnStmt hsc_env ictxt rdr_stmt
842 = initTcPrintErrors hsc_env iNTERACTIVE $
843 setInteractiveContext hsc_env ictxt $ do {
845 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
846 (([rn_stmt], _), fvs) <- rnStmts DoExpr [rdr_stmt] (return ((), emptyFVs)) ;
847 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
850 -- The real work is done here
851 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
852 zonked_expr <- zonkTopLExpr tc_expr ;
853 zonked_ids <- zonkTopBndrs bound_ids ;
855 -- None of the Ids should be of unboxed type, because we
856 -- cast them all to HValues in the end!
857 mappM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
859 traceTc (text "tcs 1") ;
860 let { -- (a) Make all the bound ids "global" ids, now that
861 -- they're notionally top-level bindings. This is
862 -- important: otherwise when we come to compile an expression
863 -- using these ids later, the byte code generator will consider
864 -- the occurrences to be free rather than global.
866 -- (b) Tidy their types; this is important, because :info may
867 -- ask to look at them, and :info expects the things it looks
868 -- up to have tidy types
869 global_ids = map globaliseAndTidy zonked_ids ;
871 -- Update the interactive context
872 rn_env = ic_rn_local_env ictxt ;
873 type_env = ic_type_env ictxt ;
875 bound_names = map idName global_ids ;
876 new_rn_env = extendLocalRdrEnv rn_env bound_names ;
878 -- Remove any shadowed bindings from the type_env;
879 -- they are inaccessible but might, I suppose, cause
880 -- a space leak if we leave them there
881 shadowed = [ n | name <- bound_names,
882 let rdr_name = mkRdrUnqual (nameOccName name),
883 Just n <- [lookupLocalRdrEnv rn_env rdr_name] ] ;
885 filtered_type_env = delListFromNameEnv type_env shadowed ;
886 new_type_env = extendTypeEnvWithIds filtered_type_env global_ids ;
888 new_ic = ictxt { ic_rn_local_env = new_rn_env,
889 ic_type_env = new_type_env }
892 dumpOptTcRn Opt_D_dump_tc
893 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
894 text "Typechecked expr" <+> ppr zonked_expr]) ;
896 returnM (new_ic, bound_names, zonked_expr)
899 bad_unboxed id = addErr (sep [ptext SLIT("GHCi can't bind a variable of unlifted type:"),
900 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
902 globaliseAndTidy :: Id -> Id
904 -- Give the Id a Global Name, and tidy its type
905 = setIdType (globaliseId VanillaGlobal id) tidy_type
907 tidy_type = tidyTopType (idType id)
910 Here is the grand plan, implemented in tcUserStmt
912 What you type The IO [HValue] that hscStmt returns
913 ------------- ------------------------------------
914 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
917 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
920 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
921 [NB: result not printed] bindings: [it]
923 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
924 result showable) bindings: [it]
926 expr (of non-IO type,
927 result not showable) ==> error
931 ---------------------------
932 type PlanResult = ([Id], LHsExpr Id)
933 type Plan = TcM PlanResult
935 runPlans :: [Plan] -> TcM PlanResult
936 -- Try the plans in order. If one fails (by raising an exn), try the next.
937 -- If one succeeds, take it.
938 runPlans [] = panic "runPlans"
940 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
943 mkPlan :: LStmt Name -> TcM PlanResult
944 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
945 = do { uniq <- newUnique -- is treated very specially
946 ; let fresh_it = itName uniq
947 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
948 matches = [mkMatch [] expr emptyLocalBinds]
949 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
950 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
951 (HsVar bindIOName) noSyntaxExpr
952 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
953 (HsVar thenIOName) placeHolderType
956 -- [it <- e; print it] but not if it::()
958 -- [let it = e; print it]
959 ; runPlans [ -- Plan A
960 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
961 ; it_ty <- zonkTcType (idType it_id)
962 ; ifM (isUnitTy it_ty) failM
965 -- Plan B; a naked bind statment
966 tcGhciStmts [bind_stmt],
968 -- Plan C; check that the let-binding is typeable all by itself.
969 -- If not, fail; if so, try to print it.
970 -- The two-step process avoids getting two errors: one from
971 -- the expression itself, and one from the 'print it' part
972 -- This two-step story is very clunky, alas
973 do { checkNoErrs (tcGhciStmts [let_stmt])
974 --- checkNoErrs defeats the error recovery of let-bindings
975 ; tcGhciStmts [let_stmt, print_it] }
978 mkPlan stmt@(L loc (BindStmt {}))
979 | [L _ v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
980 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
981 (HsVar thenIOName) placeHolderType
983 ; print_bind_result <- doptM Opt_PrintBindResult
984 ; let print_plan = do
985 { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
986 ; v_ty <- zonkTcType (idType v_id)
987 ; ifM (isUnitTy v_ty || not (isTauTy v_ty)) failM
991 -- [stmt; print v] but not if v::()
993 ; runPlans ((if print_bind_result then [print_plan] else []) ++
994 [tcGhciStmts [stmt]])
1000 ---------------------------
1001 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
1003 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
1004 ret_id <- tcLookupId returnIOName ; -- return @ IO
1006 io_ty = mkTyConApp ioTyCon [] ;
1007 ret_ty = mkListTy unitTy ;
1008 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
1009 tc_io_stmts stmts = tcStmts DoExpr (tcDoStmt io_ty) stmts
1010 (emptyRefinement, io_ret_ty) ;
1012 names = map unLoc (collectLStmtsBinders stmts) ;
1014 -- mk_return builds the expression
1015 -- returnIO @ [()] [coerce () x, .., coerce () z]
1017 -- Despite the inconvenience of building the type applications etc,
1018 -- this *has* to be done in type-annotated post-typecheck form
1019 -- because we are going to return a list of *polymorphic* values
1020 -- coerced to type (). If we built a *source* stmt
1021 -- return [coerce x, ..., coerce z]
1022 -- then the type checker would instantiate x..z, and we wouldn't
1023 -- get their *polymorphic* values. (And we'd get ambiguity errs
1024 -- if they were overloaded, since they aren't applied to anything.)
1025 mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty])
1026 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1027 mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
1031 -- OK, we're ready to typecheck the stmts
1032 traceTc (text "tcs 2") ;
1033 ((tc_stmts, ids), lie) <- getLIE $ tc_io_stmts stmts $ \ _ ->
1034 mappM tcLookupId names ;
1035 -- Look up the names right in the middle,
1036 -- where they will all be in scope
1038 -- Simplify the context
1039 const_binds <- checkNoErrs (tcSimplifyInteractive lie) ;
1040 -- checkNoErrs ensures that the plan fails if context redn fails
1042 return (ids, mkHsDictLet const_binds $
1043 noLoc (HsDo DoExpr tc_stmts (mk_return ids) io_ret_ty))
1048 tcRnExpr just finds the type of an expression
1052 -> InteractiveContext
1055 tcRnExpr hsc_env ictxt rdr_expr
1056 = initTcPrintErrors hsc_env iNTERACTIVE $
1057 setInteractiveContext hsc_env ictxt $ do {
1059 (rn_expr, fvs) <- rnLExpr rdr_expr ;
1062 -- Now typecheck the expression;
1063 -- it might have a rank-2 type (e.g. :t runST)
1064 ((tc_expr, res_ty), lie) <- getLIE (tcInferRho rn_expr) ;
1065 ((qtvs, _, dict_ids), lie_top) <- getLIE (tcSimplifyInfer smpl_doc (tyVarsOfType res_ty) lie) ;
1066 tcSimplifyInteractive lie_top ;
1067 qtvs' <- mappM zonkQuantifiedTyVar qtvs ;
1069 let { all_expr_ty = mkForAllTys qtvs' $
1070 mkFunTys (map idType dict_ids) $
1072 zonkTcType all_expr_ty
1075 smpl_doc = ptext SLIT("main expression")
1078 tcRnType just finds the kind of a type
1082 -> InteractiveContext
1085 tcRnType hsc_env ictxt rdr_type
1086 = initTcPrintErrors hsc_env iNTERACTIVE $
1087 setInteractiveContext hsc_env ictxt $ do {
1089 rn_type <- rnLHsType doc rdr_type ;
1092 -- Now kind-check the type
1093 (ty', kind) <- kcHsType rn_type ;
1097 doc = ptext SLIT("In GHCi input")
1103 %************************************************************************
1105 More GHCi stuff, to do with browsing and getting info
1107 %************************************************************************
1111 -- ASSUMES that the module is either in the HomePackageTable or is
1112 -- a package module with an interface on disk. If neither of these is
1113 -- true, then the result will be an error indicating the interface
1114 -- could not be found.
1115 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe NameSet)
1116 getModuleExports hsc_env mod
1117 = initTc hsc_env HsSrcFile iNTERACTIVE (tcGetModuleExports mod)
1119 tcGetModuleExports :: Module -> TcM NameSet
1120 tcGetModuleExports mod = do
1121 let doc = ptext SLIT("context for compiling statements")
1122 iface <- initIfaceTcRn $ loadSysInterface doc mod
1123 loadOrphanModules (dep_orphs (mi_deps iface))
1124 -- Load any orphan-module interfaces,
1125 -- so their instances are visible
1126 ifaceExportNames (mi_exports iface)
1128 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Maybe [Name])
1129 tcRnLookupRdrName hsc_env rdr_name
1130 = initTcPrintErrors hsc_env iNTERACTIVE $
1131 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1132 lookup_rdr_name rdr_name
1134 lookup_rdr_name rdr_name = do {
1135 -- If the identifier is a constructor (begins with an
1136 -- upper-case letter), then we need to consider both
1137 -- constructor and type class identifiers.
1138 let { rdr_names = dataTcOccs rdr_name } ;
1140 -- results :: [Either Messages Name]
1141 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1143 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1144 -- The successful lookups will be (Just name)
1145 let { (warns_s, good_names) = unzip [ (msgs, name)
1146 | (msgs, Just name) <- results] ;
1147 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1149 -- Fail if nothing good happened, else add warnings
1150 if null good_names then
1151 -- No lookup succeeded, so
1152 -- pick the first error message and report it
1153 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1154 -- while the other is "X is not in scope",
1155 -- we definitely want the former; but we might pick the latter
1156 do { addMessages (head errs_s) ; failM }
1157 else -- Add deprecation warnings
1158 mapM_ addMessages warns_s ;
1164 tcRnLookupName :: HscEnv -> Name -> IO (Maybe TyThing)
1165 tcRnLookupName hsc_env name
1166 = initTcPrintErrors hsc_env iNTERACTIVE $
1167 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1171 tcRnGetInfo :: HscEnv
1173 -> IO (Maybe (TyThing, Fixity, [Instance]))
1175 -- Used to implemnent :info in GHCi
1177 -- Look up a RdrName and return all the TyThings it might be
1178 -- A capitalised RdrName is given to us in the DataName namespace,
1179 -- but we want to treat it as *both* a data constructor
1180 -- *and* as a type or class constructor;
1181 -- hence the call to dataTcOccs, and we return up to two results
1182 tcRnGetInfo hsc_env name
1183 = initTcPrintErrors hsc_env iNTERACTIVE $
1184 let ictxt = hsc_IC hsc_env in
1185 setInteractiveContext hsc_env ictxt $ do
1187 -- Load the interface for all unqualified types and classes
1188 -- That way we will find all the instance declarations
1189 -- (Packages have not orphan modules, and we assume that
1190 -- in the home package all relevant modules are loaded.)
1191 loadUnqualIfaces ictxt
1193 thing <- tcLookupGlobal name
1194 fixity <- lookupFixityRn name
1195 ispecs <- lookupInsts (icPrintUnqual ictxt) thing
1196 return (thing, fixity, ispecs)
1199 lookupInsts :: PrintUnqualified -> TyThing -> TcM [Instance]
1200 -- Filter the instances by the ones whose tycons (or clases resp)
1201 -- are in scope unqualified. Otherwise we list a whole lot too many!
1202 lookupInsts print_unqual (AClass cls)
1203 = do { inst_envs <- tcGetInstEnvs
1205 | ispec <- classInstances inst_envs cls
1206 , plausibleDFun print_unqual (instanceDFunId ispec) ] }
1208 lookupInsts print_unqual (ATyCon tc)
1209 = do { eps <- getEps -- Load all instances for all classes that are
1210 -- in the type environment (which are all the ones
1211 -- we've seen in any interface file so far)
1212 ; (pkg_ie, home_ie) <- tcGetInstEnvs -- Search all
1214 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1215 , let dfun = instanceDFunId ispec
1217 , plausibleDFun print_unqual dfun ] }
1219 relevant df = tc_name `elemNameSet` tyClsNamesOfDFunHead (idType df)
1220 tc_name = tyConName tc
1222 lookupInsts print_unqual other = return []
1224 plausibleDFun print_unqual dfun -- Dfun involving only names that print unqualified
1225 = all ok (nameSetToList (tyClsNamesOfType (idType dfun)))
1227 ok name | isBuiltInSyntax name = True
1228 | isExternalName name =
1229 isNothing $ fst print_unqual (nameModule name)
1233 loadUnqualIfaces :: InteractiveContext -> TcM ()
1234 -- Load the home module for everything that is in scope unqualified
1235 -- This is so that we can accurately report the instances for
1237 loadUnqualIfaces ictxt
1239 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1241 unqual_mods = [ nameModule name
1242 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1243 let name = gre_name gre,
1244 not (isInternalName name),
1245 isTcOcc (nameOccName name), -- Types and classes only
1246 unQualOK gre ] -- In scope unqualified
1247 doc = ptext SLIT("Need interface for module whose export(s) are in scope unqualified")
1251 %************************************************************************
1255 %************************************************************************
1258 rnDump :: SDoc -> TcRn ()
1259 -- Dump, with a banner, if -ddump-rn
1260 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1262 tcDump :: TcGblEnv -> TcRn ()
1264 = do { dflags <- getDOpts ;
1266 -- Dump short output if -ddump-types or -ddump-tc
1267 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1268 (dumpTcRn short_dump) ;
1270 -- Dump bindings if -ddump-tc
1271 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1274 short_dump = pprTcGblEnv env
1275 full_dump = pprLHsBinds (tcg_binds env)
1276 -- NB: foreign x-d's have undefined's in their types;
1277 -- hence can't show the tc_fords
1280 = do { dflags <- getDOpts ;
1281 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1282 (dumpTcRn (pprModGuts mod_guts)) ;
1284 -- Dump bindings if -ddump-tc
1285 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1287 full_dump = pprCoreBindings (mg_binds mod_guts)
1289 -- It's unpleasant having both pprModGuts and pprModDetails here
1290 pprTcGblEnv :: TcGblEnv -> SDoc
1291 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1292 tcg_insts = dfun_ids,
1294 tcg_imports = imports })
1295 = vcat [ ppr_types dfun_ids type_env
1296 , ppr_insts dfun_ids
1297 , vcat (map ppr rules)
1298 , ppr_gen_tycons (typeEnvTyCons type_env)
1299 , ptext SLIT("Dependent modules:") <+> ppr (eltsUFM (imp_dep_mods imports))
1300 , ptext SLIT("Dependent packages:") <+> ppr (imp_dep_pkgs imports)]
1302 pprModGuts :: ModGuts -> SDoc
1303 pprModGuts (ModGuts { mg_types = type_env,
1305 = vcat [ ppr_types [] type_env,
1309 ppr_types :: [Instance] -> TypeEnv -> SDoc
1310 ppr_types ispecs type_env
1311 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1313 dfun_ids = map instanceDFunId ispecs
1314 ids = [id | id <- typeEnvIds type_env, want_sig id]
1315 want_sig id | opt_PprStyle_Debug = True
1316 | otherwise = isLocalId id &&
1317 isExternalName (idName id) &&
1318 not (id `elem` dfun_ids)
1319 -- isLocalId ignores data constructors, records selectors etc.
1320 -- The isExternalName ignores local dictionary and method bindings
1321 -- that the type checker has invented. Top-level user-defined things
1322 -- have External names.
1324 ppr_insts :: [Instance] -> SDoc
1325 ppr_insts [] = empty
1326 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1328 ppr_sigs :: [Var] -> SDoc
1330 -- Print type signatures; sort by OccName
1331 = vcat (map ppr_sig (sortLe le_sig ids))
1333 le_sig id1 id2 = getOccName id1 <= getOccName id2
1334 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1336 ppr_rules :: [CoreRule] -> SDoc
1337 ppr_rules [] = empty
1338 ppr_rules rs = vcat [ptext SLIT("{-# RULES"),
1339 nest 4 (pprRules rs),
1342 ppr_gen_tycons [] = empty
1343 ppr_gen_tycons tcs = vcat [ptext SLIT("Tycons with generics:"),
1344 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]