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 )
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, mkTyVarTys, substTyWith )
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 TcSimplify ( tcSimplifyTop )
52 import TcTyClsDecls ( tcTyAndClassDecls )
53 import LoadIface ( loadOrphanModules )
54 import RnNames ( importsFromLocalDecls, rnImports, rnExports,
55 mkRdrEnvAndImports, mkExportNameSet,
56 reportUnusedNames, reportDeprecations )
57 import RnEnv ( lookupSrcOcc_maybe )
58 import RnSource ( rnSrcDecls, rnTyClDecls, checkModDeprec )
59 import PprCore ( pprRules, pprCoreBindings )
60 import CoreSyn ( CoreRule, bindersOfBinds )
61 import DataCon ( dataConWrapId )
62 import ErrUtils ( Messages, mkDumpDoc, showPass )
63 import Id ( Id, mkExportedLocalId, isLocalId, idName, idType )
66 import UniqFM ( elemUFM, eltsUFM )
67 import OccName ( mkVarOccFS, plusOccEnv )
68 import Name ( Name, NamedThing(..), isExternalName, getSrcLoc, isWiredInName,
71 import TyCon ( tyConHasGenerics, isSynTyCon, synTyConDefn, tyConKind )
72 import SrcLoc ( srcLocSpan, Located(..), noLoc )
73 import DriverPhases ( HscSource(..), isHsBoot )
74 import HscTypes ( ModGuts(..), ModDetails(..), emptyModDetails,
75 HscEnv(..), ExternalPackageState(..),
76 IsBootInterface, noDependencies,
77 Deprecs( NoDeprecs ), plusDeprecs,
78 ForeignStubs(NoStubs), TyThing(..),
79 TypeEnv, lookupTypeEnv, hptInstances,
80 extendTypeEnvWithIds, typeEnvIds, typeEnvTyCons, typeEnvElts,
86 import HsSyn ( HsStmtContext(..), Stmt(..), HsExpr(..),
87 HsLocalBinds(..), HsValBinds(..),
88 LStmt, LHsExpr, LHsType, mkMatch, emptyLocalBinds,
89 collectLStmtsBinders, collectLStmtBinders, nlVarPat,
90 mkFunBind, placeHolderType, noSyntaxExpr )
91 import RdrName ( GlobalRdrElt(..), globalRdrEnvElts,
92 unQualOK, lookupLocalRdrEnv, extendLocalRdrEnv )
93 import RnSource ( addTcgDUs )
94 import TcHsSyn ( mkHsDictLet, zonkTopLExpr, zonkTopBndrs )
95 import TcHsType ( kcHsType )
96 import TcMType ( zonkTcType, zonkQuantifiedTyVar )
97 import TcMatches ( tcStmts, tcDoStmt )
98 import TcSimplify ( tcSimplifyInteractive, tcSimplifyInfer )
99 import TcType ( Type, mkForAllTys, mkFunTys, mkTyConApp, tyVarsOfType, isTauTy,
100 isUnLiftedType, tyClsNamesOfDFunHead, tyClsNamesOfType, isUnitTy )
101 import TcEnv ( tcLookupTyCon, tcLookupId, tcLookupGlobal )
102 import RnTypes ( rnLHsType )
103 import Inst ( tcGetInstEnvs )
104 import InstEnv ( classInstances, instEnvElts )
105 import RnExpr ( rnStmts, rnLExpr )
106 import LoadIface ( loadSysInterface )
107 import IfaceEnv ( ifaceExportNames )
108 import RnEnv ( lookupOccRn, dataTcOccs, lookupFixityRn )
109 import Id ( setIdType )
110 import MkId ( unsafeCoerceId )
111 import TyCon ( tyConName )
112 import TysWiredIn ( mkListTy, unitTy )
113 import IdInfo ( GlobalIdDetails(..) )
115 import Var ( globaliseId )
116 import Name ( nameOccName, nameModule, isBuiltInSyntax, isInternalName )
117 import OccName ( isTcOcc )
118 import NameEnv ( delListFromNameEnv )
119 import PrelNames ( iNTERACTIVE, ioTyConName, printName, itName,
120 bindIOName, thenIOName, returnIOName )
121 import HscTypes ( InteractiveContext(..),
122 ModIface(..), icPrintUnqual,
124 import BasicTypes ( Fixity, RecFlag(..) )
125 import SrcLoc ( unLoc )
128 import FastString ( mkFastString )
129 import Util ( sortLe )
130 import Bag ( unionBags, snocBag, emptyBag, unitBag, unionManyBags )
132 import Data.Maybe ( isJust, isNothing )
137 %************************************************************************
139 Typecheck and rename a module
141 %************************************************************************
147 -> Bool -- True <=> save renamed syntax
148 -> Located (HsModule RdrName)
149 -> IO (Messages, Maybe TcGblEnv)
151 tcRnModule hsc_env hsc_src save_rn_syntax
152 (L loc (HsModule maybe_mod export_ies
153 import_decls local_decls mod_deprec))
154 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
156 let { this_pkg = thisPackage (hsc_dflags hsc_env) ;
157 this_mod = case maybe_mod of
158 Nothing -> mAIN -- 'module M where' is omitted
159 Just (L _ mod) -> mkModule this_pkg mod } ;
162 initTc hsc_env hsc_src this_mod $
165 -- Deal with imports;
166 rn_imports <- rnImports import_decls ;
167 (rdr_env, imports) <- mkRdrEnvAndImports rn_imports ;
169 let { dep_mods :: ModuleNameEnv (ModuleName, IsBootInterface)
170 ; dep_mods = imp_dep_mods imports
172 -- We want instance declarations from all home-package
173 -- modules below this one, including boot modules, except
174 -- ourselves. The 'except ourselves' is so that we don't
175 -- get the instances from this module's hs-boot file
176 ; want_instances :: ModuleName -> Bool
177 ; want_instances mod = mod `elemUFM` dep_mods
178 && mod /= moduleName this_mod
179 ; home_insts = hptInstances hsc_env want_instances
182 -- Record boot-file info in the EPS, so that it's
183 -- visible to loadHiBootInterface in tcRnSrcDecls,
184 -- and any other incrementally-performed imports
185 updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
187 -- Update the gbl env
189 gbl { tcg_rdr_env = plusOccEnv (tcg_rdr_env gbl) rdr_env,
190 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
191 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
192 tcg_rn_imports = if save_rn_syntax then
196 tcg_rn_decls = if save_rn_syntax then
202 traceRn (text "rn1" <+> ppr (imp_dep_mods imports)) ;
203 -- Fail if there are any errors so far
204 -- The error printing (if needed) takes advantage
205 -- of the tcg_env we have now set
208 -- Load any orphan-module interfaces, so that
209 -- their rules and instance decls will be found
210 loadOrphanModules (imp_orphs imports) ;
212 traceRn (text "rn1a") ;
213 -- Rename and type check the declarations
214 tcg_env <- if isHsBoot hsc_src then
215 tcRnHsBootDecls local_decls
217 tcRnSrcDecls local_decls ;
218 setGblEnv tcg_env $ do {
220 traceRn (text "rn3") ;
222 -- Report the use of any deprecated things
223 -- We do this before processsing the export list so
224 -- that we don't bleat about re-exporting a deprecated
225 -- thing (especially via 'module Foo' export item)
226 -- Only uses in the body of the module are complained about
227 reportDeprecations (hsc_dflags hsc_env) tcg_env ;
229 -- Process the export list
230 rn_exports <- rnExports export_ies ;
231 let { liftM2' fn a b = do a' <- a; b' <- b; return (fn a' b') } ;
232 exports <- mkExportNameSet (isJust maybe_mod) (liftM2' (,) rn_exports export_ies) ;
234 -- Check whether the entire module is deprecated
235 -- This happens only once per module
236 let { mod_deprecs = checkModDeprec mod_deprec } ;
238 -- Add exports and deprecations to envt
239 let { final_env = tcg_env { tcg_exports = exports,
240 tcg_rn_exports = if save_rn_syntax then
243 tcg_dus = tcg_dus tcg_env `plusDU` usesOnly exports,
244 tcg_deprecs = tcg_deprecs tcg_env `plusDeprecs`
246 -- A module deprecation over-rides the earlier ones
249 -- Report unused names
250 reportUnusedNames export_ies final_env ;
252 -- Dump output and return
259 %************************************************************************
261 Type-checking external-core modules
263 %************************************************************************
266 tcRnExtCore :: HscEnv
268 -> IO (Messages, Maybe ModGuts)
269 -- Nothing => some error occurred
271 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
272 -- The decls are IfaceDecls; all names are original names
273 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
275 initTc hsc_env ExtCoreFile this_mod $ do {
277 let { ldecls = map noLoc decls } ;
279 -- Deal with the type declarations; first bring their stuff
280 -- into scope, then rname them, then type check them
281 tcg_env <- importsFromLocalDecls (mkFakeGroup ldecls) ;
283 setGblEnv tcg_env $ do {
285 rn_decls <- rnTyClDecls ldecls ;
288 -- Dump trace of renaming part
289 rnDump (ppr rn_decls) ;
291 -- Typecheck them all together so that
292 -- any mutually recursive types are done right
293 tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails rn_decls) ;
294 -- Make the new type env available to stuff slurped from interface files
296 setGblEnv tcg_env $ do {
298 -- Now the core bindings
299 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
303 bndrs = bindersOfBinds core_binds ;
304 my_exports = mkNameSet (map idName bndrs) ;
305 -- ToDo: export the data types also?
307 final_type_env = extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
309 mod_guts = ModGuts { mg_module = this_mod,
311 mg_usages = [], -- ToDo: compute usage
312 mg_dir_imps = [], -- ??
313 mg_deps = noDependencies, -- ??
314 mg_exports = my_exports,
315 mg_types = final_type_env,
316 mg_insts = tcg_insts tcg_env,
318 mg_binds = core_binds,
321 mg_rdr_env = emptyGlobalRdrEnv,
322 mg_fix_env = emptyFixityEnv,
323 mg_deprecs = NoDeprecs,
327 tcCoreDump mod_guts ;
332 mkFakeGroup decls -- Rather clumsy; lots of unused fields
333 = emptyRdrGroup { hs_tyclds = decls }
337 %************************************************************************
339 Type-checking the top level of a module
341 %************************************************************************
344 tcRnSrcDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
345 -- Returns the variables free in the decls
346 -- Reason: solely to report unused imports and bindings
348 = do { -- Load the hi-boot interface for this module, if any
349 -- We do this now so that the boot_names can be passed
350 -- to tcTyAndClassDecls, because the boot_names are
351 -- automatically considered to be loop breakers
353 boot_iface <- tcHiBootIface mod ;
355 -- Do all the declarations
356 (tc_envs, lie) <- getLIE (tc_rn_src_decls boot_iface decls) ;
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
361 -- restriction, and no subsequent decl instantiates its
362 -- type. (Usually, ambiguous type variables are resolved
363 -- during the generalisation step.)
364 traceTc (text "Tc8") ;
365 inst_binds <- setEnvs tc_envs (tcSimplifyTop lie) ;
366 -- Setting the global env exposes the instances to tcSimplifyTop
367 -- Setting the local env exposes the local Ids to tcSimplifyTop,
368 -- so that we get better error messages (monomorphism restriction)
370 -- Backsubstitution. This must be done last.
371 -- Even tcSimplifyTop may do some unification.
372 traceTc (text "Tc9") ;
373 let { (tcg_env, _) = tc_envs ;
374 TcGblEnv { tcg_type_env = type_env, tcg_binds = binds,
375 tcg_rules = rules, tcg_fords = fords } = tcg_env } ;
378 (bind_ids, binds', fords', rules') <- zonkTopDecls (binds `unionBags` inst_binds)
381 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
382 ; tcg_env' = tcg_env { tcg_type_env = final_type_env,
385 tcg_fords = fords' } } ;
387 -- Make the new type env available to stuff slurped from interface files
388 writeMutVar (tcg_type_env_var tcg_env) final_type_env ;
390 -- Compare the hi-boot iface (if any) with the real thing
391 dfun_binds <- checkHiBootIface tcg_env' boot_iface ;
393 return (tcg_env' { tcg_binds = tcg_binds tcg_env' `unionBags` dfun_binds })
396 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
397 -- Loops around dealing with each top level inter-splice group
398 -- in turn, until it's dealt with the entire module
399 tc_rn_src_decls boot_details ds
400 = do { let { (first_group, group_tail) = findSplice ds } ;
401 -- If ds is [] we get ([], Nothing)
403 -- Type check the decls up to, but not including, the first splice
404 tc_envs@(tcg_env,tcl_env) <- tcRnGroup boot_details first_group ;
406 -- Bale out if errors; for example, error recovery when checking
407 -- the RHS of 'main' can mean that 'main' is not in the envt for
408 -- the subsequent checkMain test
413 -- If there is no splice, we're nearly done
415 Nothing -> do { -- Last thing: check for `main'
416 tcg_env <- checkMain ;
417 return (tcg_env, tcl_env)
420 -- If there's a splice, we must carry on
421 Just (SpliceDecl splice_expr, rest_ds) -> do {
423 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
426 -- Rename the splice expression, and get its supporting decls
427 (rn_splice_expr, splice_fvs) <- rnLExpr splice_expr ;
428 failIfErrsM ; -- Don't typecheck if renaming failed
430 -- Execute the splice
431 spliced_decls <- tcSpliceDecls rn_splice_expr ;
433 -- Glue them on the front of the remaining decls and loop
434 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
435 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
440 %************************************************************************
442 Compiling hs-boot source files, and
443 comparing the hi-boot interface with the real thing
445 %************************************************************************
448 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
449 tcRnHsBootDecls decls
450 = do { let { (first_group, group_tail) = findSplice decls }
453 Just stuff -> spliceInHsBootErr stuff
456 -- Rename the declarations
457 ; (tcg_env, rn_group) <- rnTopSrcDecls first_group
458 ; setGblEnv tcg_env $ do {
460 -- Todo: check no foreign decls, no rules, no default decls
462 -- Typecheck type/class decls
463 ; traceTc (text "Tc2")
464 ; let tycl_decls = hs_tyclds rn_group
465 ; tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails tycl_decls)
466 ; setGblEnv tcg_env $ do {
468 -- Typecheck instance decls
469 ; traceTc (text "Tc3")
470 ; (tcg_env, inst_infos, _binds) <- tcInstDecls1 tycl_decls (hs_instds rn_group)
471 ; setGblEnv tcg_env $ do {
473 -- Typecheck value declarations
474 ; traceTc (text "Tc5")
475 ; val_ids <- tcHsBootSigs (hs_valds rn_group)
478 -- No simplification or zonking to do
479 ; traceTc (text "Tc7a")
480 ; gbl_env <- getGblEnv
482 -- Make the final type-env
483 -- Include the dfun_ids so that their type sigs get
484 -- are written into the interface file
485 ; let { type_env0 = tcg_type_env gbl_env
486 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
487 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
488 ; dfun_ids = map iDFunId inst_infos }
489 ; return (gbl_env { tcg_type_env = type_env2 })
492 spliceInHsBootErr (SpliceDecl (L loc _), _)
493 = addErrAt loc (ptext SLIT("Splices are not allowed in hs-boot files"))
496 Once we've typechecked the body of the module, we want to compare what
497 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
500 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM (LHsBinds Id)
501 -- Compare the hi-boot file for this module (if there is one)
502 -- with the type environment we've just come up with
503 -- In the common case where there is no hi-boot file, the list
504 -- of boot_names is empty.
506 -- The bindings we return give bindings for the dfuns defined in the
507 -- hs-boot file, such as $fbEqT = $fEqT
510 (TcGblEnv { tcg_insts = local_insts, tcg_type_env = local_type_env })
511 (ModDetails { md_insts = boot_insts, md_types = boot_type_env })
512 = do { mapM_ check_one (typeEnvElts boot_type_env)
513 ; dfun_binds <- mapM check_inst boot_insts
514 ; return (unionManyBags dfun_binds) }
520 = case lookupTypeEnv local_type_env name of
521 Nothing -> addErrTc (missingBootThing boot_thing)
522 Just real_thing -> check_thing boot_thing real_thing
524 name = getName boot_thing
526 no_check name = isWiredInName name -- No checking for wired-in names. In particular,
527 -- 'error' is handled by a rather gross hack
528 -- (see comments in GHC.Err.hs-boot)
529 || name `elem` dfun_names
530 dfun_names = map getName boot_insts
533 = case [dfun | inst <- local_insts,
534 let dfun = instanceDFunId inst,
535 idType dfun `tcEqType` boot_inst_ty ] of
536 [] -> do { addErrTc (instMisMatch boot_inst); return emptyBag }
537 (dfun:_) -> return (unitBag $ noLoc $ VarBind local_boot_dfun (nlHsVar dfun))
539 boot_dfun = instanceDFunId boot_inst
540 boot_inst_ty = idType boot_dfun
541 local_boot_dfun = mkExportedLocalId (idName boot_dfun) boot_inst_ty
544 check_thing (ATyCon boot_tc) (ATyCon real_tc)
545 | isSynTyCon boot_tc && isSynTyCon real_tc,
546 defn1 `tcEqType` substTyWith tvs2 (mkTyVarTys tvs1) defn2
549 | tyConKind boot_tc == tyConKind real_tc
552 (tvs1, defn1) = synTyConDefn boot_tc
553 (tvs2, defn2) = synTyConDefn boot_tc
555 check_thing (AnId boot_id) (AnId real_id)
556 | idType boot_id `tcEqType` idType real_id
559 check_thing (ADataCon dc1) (ADataCon dc2)
560 | idType (dataConWrapId dc1) `tcEqType` idType (dataConWrapId dc2)
563 -- Can't declare a class in a hi-boot file
565 check_thing boot_thing real_thing -- Default case; failure
566 = addErrAt (srcLocSpan (getSrcLoc real_thing))
567 (bootMisMatch real_thing)
570 missingBootThing thing
571 = ppr thing <+> ptext SLIT("is defined in the hs-boot file, but not in the module")
573 = ppr thing <+> ptext SLIT("has conflicting definitions in the module and its hs-boot file")
576 2 (ptext SLIT("is defined in the hs-boot file, but not in the module"))
580 %************************************************************************
582 Type-checking the top level of a module
584 %************************************************************************
586 tcRnGroup takes a bunch of top-level source-code declarations, and
588 * gets supporting declarations from interface files
591 * and augments the TcGblEnv with the results
593 In Template Haskell it may be called repeatedly for each group of
594 declarations. It expects there to be an incoming TcGblEnv in the
595 monad; it augments it and returns the new TcGblEnv.
598 tcRnGroup :: ModDetails -> HsGroup RdrName -> TcM (TcGblEnv, TcLclEnv)
599 -- Returns the variables free in the decls, for unused-binding reporting
600 tcRnGroup boot_details decls
601 = do { -- Rename the declarations
602 (tcg_env, rn_decls) <- rnTopSrcDecls decls ;
603 setGblEnv tcg_env $ do {
605 -- Typecheck the declarations
606 tcTopSrcDecls boot_details rn_decls
609 ------------------------------------------------
610 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
612 = do { -- Bring top level binders into scope
613 tcg_env <- importsFromLocalDecls group ;
614 setGblEnv tcg_env $ do {
616 failIfErrsM ; -- No point in continuing if (say) we have duplicate declarations
618 -- Rename the source decls
619 (tcg_env, rn_decls) <- rnSrcDecls group ;
622 -- save the renamed syntax, if we want it
624 | Just grp <- tcg_rn_decls tcg_env
625 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
629 -- Dump trace of renaming part
630 rnDump (ppr rn_decls) ;
632 return (tcg_env', rn_decls)
635 ------------------------------------------------
636 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
637 tcTopSrcDecls boot_details
638 (HsGroup { hs_tyclds = tycl_decls,
639 hs_instds = inst_decls,
640 hs_fords = foreign_decls,
641 hs_defds = default_decls,
642 hs_ruleds = rule_decls,
643 hs_valds = val_binds })
644 = do { -- Type-check the type and class decls, and all imported decls
645 -- The latter come in via tycl_decls
646 traceTc (text "Tc2") ;
648 tcg_env <- checkNoErrs (tcTyAndClassDecls boot_details tycl_decls) ;
649 -- tcTyAndClassDecls recovers internally, but if anything gave rise to
650 -- an error we'd better stop now, to avoid a cascade
652 -- Make these type and class decls available to stuff slurped from interface files
653 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
656 setGblEnv tcg_env $ do {
657 -- Source-language instances, including derivings,
658 -- and import the supporting declarations
659 traceTc (text "Tc3") ;
660 (tcg_env, inst_infos, deriv_binds) <- tcInstDecls1 tycl_decls inst_decls ;
661 setGblEnv tcg_env $ do {
663 -- Foreign import declarations next. No zonking necessary
664 -- here; we can tuck them straight into the global environment.
665 traceTc (text "Tc4") ;
666 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
667 tcExtendGlobalValEnv fi_ids $ do {
669 -- Default declarations
670 traceTc (text "Tc4a") ;
671 default_tys <- tcDefaults default_decls ;
672 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
674 -- Value declarations next
675 -- We also typecheck any extra binds that came out
676 -- of the "deriving" process (deriv_binds)
677 traceTc (text "Tc5") ;
678 (tc_val_binds, tcl_env) <- tcTopBinds (val_binds `plusHsValBinds` deriv_binds) ;
679 setLclTypeEnv tcl_env $ do {
681 -- Second pass over class and instance declarations,
682 traceTc (text "Tc6") ;
683 (inst_binds, tcl_env) <- tcInstDecls2 tycl_decls inst_infos ;
684 showLIE (text "after instDecls2") ;
687 -- They need to be zonked, so we return them
688 traceTc (text "Tc7") ;
689 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
692 rules <- tcRules rule_decls ;
695 traceTc (text "Tc7a") ;
696 tcg_env <- getGblEnv ;
697 let { all_binds = tc_val_binds `unionBags`
698 inst_binds `unionBags`
701 -- Extend the GblEnv with the (as yet un-zonked)
702 -- bindings, rules, foreign decls
703 tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds,
704 tcg_rules = tcg_rules tcg_env ++ rules,
705 tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
706 return (tcg_env', tcl_env)
711 %************************************************************************
715 %************************************************************************
718 checkMain :: TcM TcGblEnv
719 -- If we are in module Main, check that 'main' is defined.
721 = do { ghc_mode <- getGhcMode ;
722 tcg_env <- getGblEnv ;
724 let { main_mod = mainModIs dflags ;
725 main_fn = case mainFunIs dflags of {
726 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn)) ;
727 Nothing -> main_RDR_Unqual } } ;
729 check_main ghc_mode tcg_env main_mod main_fn
733 check_main ghc_mode tcg_env main_mod main_fn
735 = traceTc (text "checkMain not" <+> ppr main_mod <+> ppr mod) >>
739 = addErrCtxt mainCtxt $
740 do { mb_main <- lookupSrcOcc_maybe main_fn
741 -- Check that 'main' is in scope
742 -- It might be imported from another module!
744 Nothing -> do { traceTc (text "checkMain fail" <+> ppr main_mod <+> ppr main_fn)
748 { traceTc (text "checkMain found" <+> ppr main_mod <+> ppr main_fn)
749 ; let { rhs = nlHsApp (nlHsVar runMainIOName) (nlHsVar main_name) }
750 -- :Main.main :: IO () = runMainIO main
752 ; (main_expr, ty) <- setSrcSpan (srcLocSpan (getSrcLoc main_name)) $
755 -- The function that the RTS invokes is always :Main.main,
756 -- which we call root_main_id.
757 -- (Because GHC allows the user to have a module not called
758 -- Main as the main module, we can't rely on the main function
759 -- being called "Main.main". That's why root_main_id has a fixed
761 -- We also make root_main_id an implicit Id, by making main_name
762 -- its parent (hence (Just main_name)). That has the effect
763 -- of preventing its type and unfolding from getting out into
764 -- the interface file. Otherwise we can end up with two defns
765 -- for 'main' in the interface file!
767 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
768 (mkVarOccFS FSLIT("main"))
769 (Just main_name) (getSrcLoc main_name)
770 ; root_main_id = mkExportedLocalId root_main_name ty
771 ; main_bind = noLoc (VarBind root_main_id main_expr) }
773 ; return (tcg_env { tcg_binds = tcg_binds tcg_env
775 tcg_dus = tcg_dus tcg_env
776 `plusDU` usesOnly (unitFV main_name)
777 -- Record the use of 'main', so that we don't
778 -- complain about it being defined but not used
782 mod = tcg_mod tcg_env
784 complain_no_main | ghc_mode == Interactive = return ()
785 | otherwise = failWithTc noMainMsg
786 -- In interactive mode, don't worry about the absence of 'main'
787 -- In other modes, fail altogether, so that we don't go on
788 -- and complain a second time when processing the export list.
790 mainCtxt = ptext SLIT("When checking the type of the main function") <+> quotes (ppr main_fn)
791 noMainMsg = ptext SLIT("The main function") <+> quotes (ppr main_fn)
792 <+> ptext SLIT("is not defined in module") <+> quotes (ppr main_mod)
795 %*********************************************************
799 %*********************************************************
803 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
804 setInteractiveContext hsc_env icxt thing_inside
806 -- Initialise the tcg_inst_env with instances
807 -- from all home modules. This mimics the more selective
808 -- call to hptInstances in tcRnModule
809 dfuns = hptInstances hsc_env (\mod -> True)
811 updGblEnv (\env -> env {
812 tcg_rdr_env = ic_rn_gbl_env icxt,
813 tcg_type_env = ic_type_env icxt,
814 tcg_inst_env = extendInstEnvList (tcg_inst_env env) dfuns }) $
816 updLclEnv (\env -> env { tcl_rdr = ic_rn_local_env icxt }) $
818 do { traceTc (text "setIC" <+> ppr (ic_type_env icxt))
825 -> InteractiveContext
827 -> IO (Maybe (InteractiveContext, [Name], LHsExpr Id))
828 -- The returned [Name] is the same as the input except for
829 -- ExprStmt, in which case the returned [Name] is [itName]
831 -- The returned TypecheckedHsExpr is of type IO [ () ],
832 -- a list of the bound values, coerced to ().
834 tcRnStmt hsc_env ictxt rdr_stmt
835 = initTcPrintErrors hsc_env iNTERACTIVE $
836 setInteractiveContext hsc_env ictxt $ do {
838 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
839 (([rn_stmt], _), fvs) <- rnStmts DoExpr [rdr_stmt] (return ((), emptyFVs)) ;
840 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
843 -- The real work is done here
844 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
845 zonked_expr <- zonkTopLExpr tc_expr ;
846 zonked_ids <- zonkTopBndrs bound_ids ;
848 -- None of the Ids should be of unboxed type, because we
849 -- cast them all to HValues in the end!
850 mappM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
852 traceTc (text "tcs 1") ;
853 let { -- (a) Make all the bound ids "global" ids, now that
854 -- they're notionally top-level bindings. This is
855 -- important: otherwise when we come to compile an expression
856 -- using these ids later, the byte code generator will consider
857 -- the occurrences to be free rather than global.
859 -- (b) Tidy their types; this is important, because :info may
860 -- ask to look at them, and :info expects the things it looks
861 -- up to have tidy types
862 global_ids = map globaliseAndTidy zonked_ids ;
864 -- Update the interactive context
865 rn_env = ic_rn_local_env ictxt ;
866 type_env = ic_type_env ictxt ;
868 bound_names = map idName global_ids ;
869 new_rn_env = extendLocalRdrEnv rn_env bound_names ;
871 -- Remove any shadowed bindings from the type_env;
872 -- they are inaccessible but might, I suppose, cause
873 -- a space leak if we leave them there
874 shadowed = [ n | name <- bound_names,
875 let rdr_name = mkRdrUnqual (nameOccName name),
876 Just n <- [lookupLocalRdrEnv rn_env rdr_name] ] ;
878 filtered_type_env = delListFromNameEnv type_env shadowed ;
879 new_type_env = extendTypeEnvWithIds filtered_type_env global_ids ;
881 new_ic = ictxt { ic_rn_local_env = new_rn_env,
882 ic_type_env = new_type_env }
885 dumpOptTcRn Opt_D_dump_tc
886 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
887 text "Typechecked expr" <+> ppr zonked_expr]) ;
889 returnM (new_ic, bound_names, zonked_expr)
892 bad_unboxed id = addErr (sep [ptext SLIT("GHCi can't bind a variable of unlifted type:"),
893 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
895 globaliseAndTidy :: Id -> Id
897 -- Give the Id a Global Name, and tidy its type
898 = setIdType (globaliseId VanillaGlobal id) tidy_type
900 tidy_type = tidyTopType (idType id)
903 Here is the grand plan, implemented in tcUserStmt
905 What you type The IO [HValue] that hscStmt returns
906 ------------- ------------------------------------
907 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
910 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
913 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
914 [NB: result not printed] bindings: [it]
916 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
917 result showable) bindings: [it]
919 expr (of non-IO type,
920 result not showable) ==> error
924 ---------------------------
925 type PlanResult = ([Id], LHsExpr Id)
926 type Plan = TcM PlanResult
928 runPlans :: [Plan] -> TcM PlanResult
929 -- Try the plans in order. If one fails (by raising an exn), try the next.
930 -- If one succeeds, take it.
931 runPlans [] = panic "runPlans"
933 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
936 mkPlan :: LStmt Name -> TcM PlanResult
937 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
938 = do { uniq <- newUnique -- is treated very specially
939 ; let fresh_it = itName uniq
940 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
941 matches = [mkMatch [] expr emptyLocalBinds]
942 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
943 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
944 (HsVar bindIOName) noSyntaxExpr
945 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
946 (HsVar thenIOName) placeHolderType
949 -- [it <- e; print it] but not if it::()
951 -- [let it = e; print it]
952 ; runPlans [ -- Plan A
953 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
954 ; it_ty <- zonkTcType (idType it_id)
955 ; ifM (isUnitTy it_ty) failM
958 -- Plan B; a naked bind statment
959 tcGhciStmts [bind_stmt],
961 -- Plan C; check that the let-binding is typeable all by itself.
962 -- If not, fail; if so, try to print it.
963 -- The two-step process avoids getting two errors: one from
964 -- the expression itself, and one from the 'print it' part
965 -- This two-step story is very clunky, alas
966 do { checkNoErrs (tcGhciStmts [let_stmt])
967 --- checkNoErrs defeats the error recovery of let-bindings
968 ; tcGhciStmts [let_stmt, print_it] }
971 mkPlan stmt@(L loc (BindStmt {}))
972 | [L _ v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
973 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
974 (HsVar thenIOName) placeHolderType
976 -- [stmt; print v] but not if v::()
978 ; runPlans [do { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
979 ; v_ty <- zonkTcType (idType v_id)
980 ; ifM (isUnitTy v_ty || not (isTauTy v_ty)) failM
988 ---------------------------
989 tcGhciStmts :: [LStmt Name] -> TcM PlanResult
991 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
992 ret_id <- tcLookupId returnIOName ; -- return @ IO
994 io_ty = mkTyConApp ioTyCon [] ;
995 ret_ty = mkListTy unitTy ;
996 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
998 names = map unLoc (collectLStmtsBinders stmts) ;
1000 -- mk_return builds the expression
1001 -- returnIO @ [()] [coerce () x, .., coerce () z]
1003 -- Despite the inconvenience of building the type applications etc,
1004 -- this *has* to be done in type-annotated post-typecheck form
1005 -- because we are going to return a list of *polymorphic* values
1006 -- coerced to type (). If we built a *source* stmt
1007 -- return [coerce x, ..., coerce z]
1008 -- then the type checker would instantiate x..z, and we wouldn't
1009 -- get their *polymorphic* values. (And we'd get ambiguity errs
1010 -- if they were overloaded, since they aren't applied to anything.)
1011 mk_return ids = nlHsApp (noLoc $ TyApp (nlHsVar ret_id) [ret_ty])
1012 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1013 mk_item id = nlHsApp (noLoc $ TyApp (nlHsVar unsafeCoerceId) [idType id, unitTy])
1017 -- OK, we're ready to typecheck the stmts
1018 traceTc (text "tcs 2") ;
1019 ((tc_stmts, ids), lie) <- getLIE $
1020 tcStmts DoExpr (tcDoStmt io_ty) stmts io_ret_ty $ \ _ ->
1021 mappM tcLookupId names ;
1022 -- Look up the names right in the middle,
1023 -- where they will all be in scope
1025 -- Simplify the context
1026 const_binds <- checkNoErrs (tcSimplifyInteractive lie) ;
1027 -- checkNoErrs ensures that the plan fails if context redn fails
1029 return (ids, mkHsDictLet const_binds $
1030 noLoc (HsDo DoExpr tc_stmts (mk_return ids) io_ret_ty))
1035 tcRnExpr just finds the type of an expression
1039 -> InteractiveContext
1042 tcRnExpr hsc_env ictxt rdr_expr
1043 = initTcPrintErrors hsc_env iNTERACTIVE $
1044 setInteractiveContext hsc_env ictxt $ do {
1046 (rn_expr, fvs) <- rnLExpr rdr_expr ;
1049 -- Now typecheck the expression;
1050 -- it might have a rank-2 type (e.g. :t runST)
1051 ((tc_expr, res_ty), lie) <- getLIE (tcInferRho rn_expr) ;
1052 ((qtvs, _, dict_ids), lie_top) <- getLIE (tcSimplifyInfer smpl_doc (tyVarsOfType res_ty) lie) ;
1053 tcSimplifyInteractive lie_top ;
1054 qtvs' <- mappM zonkQuantifiedTyVar qtvs ;
1056 let { all_expr_ty = mkForAllTys qtvs' $
1057 mkFunTys (map idType dict_ids) $
1059 zonkTcType all_expr_ty
1062 smpl_doc = ptext SLIT("main expression")
1065 tcRnType just finds the kind of a type
1069 -> InteractiveContext
1072 tcRnType hsc_env ictxt rdr_type
1073 = initTcPrintErrors hsc_env iNTERACTIVE $
1074 setInteractiveContext hsc_env ictxt $ do {
1076 rn_type <- rnLHsType doc rdr_type ;
1079 -- Now kind-check the type
1080 (ty', kind) <- kcHsType rn_type ;
1084 doc = ptext SLIT("In GHCi input")
1090 %************************************************************************
1092 More GHCi stuff, to do with browsing and getting info
1094 %************************************************************************
1098 -- ASSUMES that the module is either in the HomePackageTable or is
1099 -- a package module with an interface on disk. If neither of these is
1100 -- true, then the result will be an error indicating the interface
1101 -- could not be found.
1102 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe NameSet)
1103 getModuleExports hsc_env mod
1104 = initTc hsc_env HsSrcFile iNTERACTIVE (tcGetModuleExports mod)
1106 tcGetModuleExports :: Module -> TcM NameSet
1107 tcGetModuleExports mod = do
1108 let doc = ptext SLIT("context for compiling statements")
1109 iface <- initIfaceTcRn $ loadSysInterface doc mod
1110 loadOrphanModules (dep_orphs (mi_deps iface))
1111 -- Load any orphan-module interfaces,
1112 -- so their instances are visible
1113 ifaceExportNames (mi_exports iface)
1115 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Maybe [Name])
1116 tcRnLookupRdrName hsc_env rdr_name
1117 = initTcPrintErrors hsc_env iNTERACTIVE $
1118 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1119 lookup_rdr_name rdr_name
1121 lookup_rdr_name rdr_name = do {
1122 -- If the identifier is a constructor (begins with an
1123 -- upper-case letter), then we need to consider both
1124 -- constructor and type class identifiers.
1125 let { rdr_names = dataTcOccs rdr_name } ;
1127 -- results :: [Either Messages Name]
1128 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1130 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1131 -- The successful lookups will be (Just name)
1132 let { (warns_s, good_names) = unzip [ (msgs, name)
1133 | (msgs, Just name) <- results] ;
1134 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1136 -- Fail if nothing good happened, else add warnings
1137 if null good_names then
1138 -- No lookup succeeded, so
1139 -- pick the first error message and report it
1140 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1141 -- while the other is "X is not in scope",
1142 -- we definitely want the former; but we might pick the latter
1143 do { addMessages (head errs_s) ; failM }
1144 else -- Add deprecation warnings
1145 mapM_ addMessages warns_s ;
1151 tcRnLookupName :: HscEnv -> Name -> IO (Maybe TyThing)
1152 tcRnLookupName hsc_env name
1153 = initTcPrintErrors hsc_env iNTERACTIVE $
1154 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1158 tcRnGetInfo :: HscEnv
1160 -> IO (Maybe (TyThing, Fixity, [Instance]))
1162 -- Used to implemnent :info in GHCi
1164 -- Look up a RdrName and return all the TyThings it might be
1165 -- A capitalised RdrName is given to us in the DataName namespace,
1166 -- but we want to treat it as *both* a data constructor
1167 -- *and* as a type or class constructor;
1168 -- hence the call to dataTcOccs, and we return up to two results
1169 tcRnGetInfo hsc_env name
1170 = initTcPrintErrors hsc_env iNTERACTIVE $
1171 let ictxt = hsc_IC hsc_env in
1172 setInteractiveContext hsc_env ictxt $ do
1174 -- Load the interface for all unqualified types and classes
1175 -- That way we will find all the instance declarations
1176 -- (Packages have not orphan modules, and we assume that
1177 -- in the home package all relevant modules are loaded.)
1178 loadUnqualIfaces ictxt
1180 thing <- tcLookupGlobal name
1181 fixity <- lookupFixityRn name
1182 ispecs <- lookupInsts (icPrintUnqual ictxt) thing
1183 return (thing, fixity, ispecs)
1186 lookupInsts :: PrintUnqualified -> TyThing -> TcM [Instance]
1187 -- Filter the instances by the ones whose tycons (or clases resp)
1188 -- are in scope unqualified. Otherwise we list a whole lot too many!
1189 lookupInsts print_unqual (AClass cls)
1190 = do { inst_envs <- tcGetInstEnvs
1192 | ispec <- classInstances inst_envs cls
1193 , plausibleDFun print_unqual (instanceDFunId ispec) ] }
1195 lookupInsts print_unqual (ATyCon tc)
1196 = do { eps <- getEps -- Load all instances for all classes that are
1197 -- in the type environment (which are all the ones
1198 -- we've seen in any interface file so far)
1199 ; (pkg_ie, home_ie) <- tcGetInstEnvs -- Search all
1201 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1202 , let dfun = instanceDFunId ispec
1204 , plausibleDFun print_unqual dfun ] }
1206 relevant df = tc_name `elemNameSet` tyClsNamesOfDFunHead (idType df)
1207 tc_name = tyConName tc
1209 lookupInsts print_unqual other = return []
1211 plausibleDFun print_unqual dfun -- Dfun involving only names that print unqualified
1212 = all ok (nameSetToList (tyClsNamesOfType (idType dfun)))
1214 ok name | isBuiltInSyntax name = True
1215 | isExternalName name =
1216 isNothing $ fst print_unqual (nameModule name)
1220 loadUnqualIfaces :: InteractiveContext -> TcM ()
1221 -- Load the home module for everything that is in scope unqualified
1222 -- This is so that we can accurately report the instances for
1224 loadUnqualIfaces ictxt
1226 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1228 unqual_mods = [ nameModule name
1229 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1230 let name = gre_name gre,
1231 not (isInternalName name),
1232 isTcOcc (nameOccName name), -- Types and classes only
1233 unQualOK gre ] -- In scope unqualified
1234 doc = ptext SLIT("Need interface for module whose export(s) are in scope unqualified")
1238 %************************************************************************
1242 %************************************************************************
1245 rnDump :: SDoc -> TcRn ()
1246 -- Dump, with a banner, if -ddump-rn
1247 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1249 tcDump :: TcGblEnv -> TcRn ()
1251 = do { dflags <- getDOpts ;
1253 -- Dump short output if -ddump-types or -ddump-tc
1254 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1255 (dumpTcRn short_dump) ;
1257 -- Dump bindings if -ddump-tc
1258 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1261 short_dump = pprTcGblEnv env
1262 full_dump = pprLHsBinds (tcg_binds env)
1263 -- NB: foreign x-d's have undefined's in their types;
1264 -- hence can't show the tc_fords
1267 = do { dflags <- getDOpts ;
1268 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1269 (dumpTcRn (pprModGuts mod_guts)) ;
1271 -- Dump bindings if -ddump-tc
1272 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1274 full_dump = pprCoreBindings (mg_binds mod_guts)
1276 -- It's unpleasant having both pprModGuts and pprModDetails here
1277 pprTcGblEnv :: TcGblEnv -> SDoc
1278 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1279 tcg_insts = dfun_ids,
1281 tcg_imports = imports })
1282 = vcat [ ppr_types dfun_ids type_env
1283 , ppr_insts dfun_ids
1284 , vcat (map ppr rules)
1285 , ppr_gen_tycons (typeEnvTyCons type_env)
1286 , ptext SLIT("Dependent modules:") <+> ppr (eltsUFM (imp_dep_mods imports))
1287 , ptext SLIT("Dependent packages:") <+> ppr (imp_dep_pkgs imports)]
1289 pprModGuts :: ModGuts -> SDoc
1290 pprModGuts (ModGuts { mg_types = type_env,
1292 = vcat [ ppr_types [] type_env,
1296 ppr_types :: [Instance] -> TypeEnv -> SDoc
1297 ppr_types ispecs type_env
1298 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1300 dfun_ids = map instanceDFunId ispecs
1301 ids = [id | id <- typeEnvIds type_env, want_sig id]
1302 want_sig id | opt_PprStyle_Debug = True
1303 | otherwise = isLocalId id &&
1304 isExternalName (idName id) &&
1305 not (id `elem` dfun_ids)
1306 -- isLocalId ignores data constructors, records selectors etc.
1307 -- The isExternalName ignores local dictionary and method bindings
1308 -- that the type checker has invented. Top-level user-defined things
1309 -- have External names.
1311 ppr_insts :: [Instance] -> SDoc
1312 ppr_insts [] = empty
1313 ppr_insts ispecs = text "INSTANCES" $$ nest 2 (pprInstances ispecs)
1315 ppr_sigs :: [Var] -> SDoc
1317 -- Print type signatures; sort by OccName
1318 = vcat (map ppr_sig (sortLe le_sig ids))
1320 le_sig id1 id2 = getOccName id1 <= getOccName id2
1321 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1323 ppr_rules :: [CoreRule] -> SDoc
1324 ppr_rules [] = empty
1325 ppr_rules rs = vcat [ptext SLIT("{-# RULES"),
1326 nest 4 (pprRules rs),
1329 ppr_gen_tycons [] = empty
1330 ppr_gen_tycons tcs = vcat [ptext SLIT("Tycons with generics:"),
1331 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]