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 Packages ( checkForPackageConflicts, mkHomeModules )
30 import HsSyn ( HsModule(..), HsExtCore(..), HsGroup(..), LHsDecl,
31 SpliceDecl(..), HsBind(..), LHsBinds,
32 emptyRdrGroup, emptyRnGroup, appendGroups, plusHsValBinds,
33 nlHsApp, nlHsVar, pprLHsBinds )
34 import RdrHsSyn ( findSplice )
36 import PrelNames ( runMainIOName, rootMainKey, rOOT_MAIN, mAIN,
38 import RdrName ( RdrName, mkRdrUnqual, emptyGlobalRdrEnv )
39 import TcHsSyn ( zonkTopDecls )
40 import TcExpr ( tcInferRho )
42 import TcType ( tidyTopType, tcEqType, mkTyVarTys, substTyWith )
43 import Inst ( showLIE )
44 import InstEnv ( extendInstEnvList, Instance, pprInstances, instanceDFunId )
45 import TcBinds ( tcTopBinds, tcHsBootSigs )
46 import TcDefaults ( tcDefaults )
47 import TcEnv ( tcExtendGlobalValEnv, iDFunId )
48 import TcRules ( tcRules )
49 import TcForeign ( tcForeignImports, tcForeignExports )
50 import TcInstDcls ( tcInstDecls1, tcInstDecls2 )
51 import TcIface ( tcExtCoreBindings, tcHiBootIface )
52 import TcSimplify ( tcSimplifyTop )
53 import TcTyClsDecls ( tcTyAndClassDecls )
54 import LoadIface ( loadOrphanModules )
55 import RnNames ( importsFromLocalDecls, rnImports, rnExports,
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 )
65 import Module ( Module, ModuleEnv, moduleEnvElts, elemModuleEnv )
66 import OccName ( mkVarOccFS )
67 import Name ( Name, NamedThing(..), isExternalName, getSrcLoc, isWiredInName,
70 import TyCon ( tyConHasGenerics, isSynTyCon, synTyConDefn, tyConKind )
71 import SrcLoc ( srcLocSpan, Located(..), noLoc )
72 import DriverPhases ( HscSource(..), isHsBoot )
73 import HscTypes ( ModGuts(..), ModDetails(..), emptyModDetails,
74 HscEnv(..), ExternalPackageState(..),
75 IsBootInterface, noDependencies,
76 Deprecs( NoDeprecs ), plusDeprecs,
77 ForeignStubs(NoStubs), TyThing(..),
78 TypeEnv, lookupTypeEnv, hptInstances,
79 extendTypeEnvWithIds, typeEnvIds, typeEnvTyCons, typeEnvElts,
85 import HsSyn ( HsStmtContext(..), Stmt(..), HsExpr(..),
86 HsLocalBinds(..), HsValBinds(..),
87 LStmt, LHsExpr, LHsType, mkMatch, emptyLocalBinds,
88 collectLStmtsBinders, collectLStmtBinders, nlVarPat,
89 mkFunBind, placeHolderType, noSyntaxExpr )
90 import RdrName ( GlobalRdrElt(..), globalRdrEnvElts,
91 unQualOK, lookupLocalRdrEnv, extendLocalRdrEnv )
92 import RnSource ( addTcgDUs )
93 import TcHsSyn ( mkHsDictLet, zonkTopLExpr, zonkTopBndrs )
94 import TcHsType ( kcHsType )
95 import TcMType ( zonkTcType, zonkQuantifiedTyVar )
96 import TcMatches ( tcStmts, tcDoStmt )
97 import TcSimplify ( tcSimplifyInteractive, tcSimplifyInfer )
98 import TcType ( Type, mkForAllTys, mkFunTys, mkTyConApp, tyVarsOfType, isTauTy,
99 isUnLiftedType, tyClsNamesOfDFunHead, tyClsNamesOfType, isUnitTy )
100 import TcEnv ( tcLookupTyCon, tcLookupId, tcLookupGlobal )
101 import RnTypes ( rnLHsType )
102 import Inst ( tcGetInstEnvs )
103 import InstEnv ( classInstances, instEnvElts )
104 import RnExpr ( rnStmts, rnLExpr )
105 import LoadIface ( loadSrcInterface, loadSysInterface )
106 import IfaceEnv ( ifaceExportNames )
107 import Module ( moduleSetElts, mkModuleSet )
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 )
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 Maybes ( MaybeErr(..) )
130 import Util ( sortLe )
131 import Bag ( unionBags, snocBag, emptyBag, unitBag, unionManyBags )
133 import Maybe ( isJust )
138 %************************************************************************
140 Typecheck and rename a module
142 %************************************************************************
148 -> Bool -- True <=> save renamed syntax
149 -> Located (HsModule RdrName)
150 -> IO (Messages, Maybe TcGblEnv)
152 tcRnModule hsc_env hsc_src save_rn_decls
153 (L loc (HsModule maybe_mod export_ies
154 import_decls local_decls mod_deprec))
155 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
157 let { this_mod = case maybe_mod of
158 Nothing -> mAIN -- 'module M where' is omitted
159 Just (L _ mod) -> mod } ; -- The normal case
161 initTc hsc_env hsc_src this_mod $
164 -- Deal with imports; sets tcg_rdr_env, tcg_imports
165 (rdr_env, imports) <- rnImports import_decls ;
167 let { dep_mods :: ModuleEnv (Module, IsBootInterface)
168 ; dep_mods = imp_dep_mods imports
170 -- We want instance declarations from all home-package
171 -- modules below this one, including boot modules, except
172 -- ourselves. The 'except ourselves' is so that we don't
173 -- get the instances from this module's hs-boot file
174 ; want_instances :: Module -> Bool
175 ; want_instances mod = mod `elemModuleEnv` dep_mods
177 ; home_insts = hptInstances hsc_env want_instances
180 -- Record boot-file info in the EPS, so that it's
181 -- visible to loadHiBootInterface in tcRnSrcDecls,
182 -- and any other incrementally-performed imports
183 updateEps_ (\eps -> eps { eps_is_boot = dep_mods }) ;
185 checkConflicts imports this_mod $ do {
187 -- Update the gbl env
189 gbl { tcg_rdr_env = rdr_env,
190 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
191 tcg_imports = tcg_imports gbl `plusImportAvails` imports,
192 tcg_rn_decls = if save_rn_decls then
198 traceRn (text "rn1" <+> ppr (imp_dep_mods imports)) ;
199 -- Fail if there are any errors so far
200 -- The error printing (if needed) takes advantage
201 -- of the tcg_env we have now set
204 -- Load any orphan-module interfaces, so that
205 -- their rules and instance decls will be found
206 loadOrphanModules (imp_orphs imports) ;
208 traceRn (text "rn1a") ;
209 -- Rename and type check the declarations
210 tcg_env <- if isHsBoot hsc_src then
211 tcRnHsBootDecls local_decls
213 tcRnSrcDecls local_decls ;
214 setGblEnv tcg_env $ do {
216 traceRn (text "rn3") ;
218 -- Report the use of any deprecated things
219 -- We do this before processsing the export list so
220 -- that we don't bleat about re-exporting a deprecated
221 -- thing (especially via 'module Foo' export item)
222 -- Only uses in the body of the module are complained about
223 reportDeprecations tcg_env ;
225 -- Process the export list
226 exports <- rnExports (isJust maybe_mod) export_ies ;
228 -- Check whether the entire module is deprecated
229 -- This happens only once per module
230 let { mod_deprecs = checkModDeprec mod_deprec } ;
232 -- Add exports and deprecations to envt
233 let { final_env = tcg_env { tcg_exports = exports,
234 tcg_dus = tcg_dus tcg_env `plusDU` usesOnly exports,
235 tcg_deprecs = tcg_deprecs tcg_env `plusDeprecs`
237 -- A module deprecation over-rides the earlier ones
240 -- Report unused names
241 reportUnusedNames export_ies final_env ;
243 -- Dump output and return
249 -- The program is not allowed to contain two modules with the same
250 -- name, and we check for that here. It could happen if the home package
251 -- contains a module that is also present in an external package, for example.
252 checkConflicts imports this_mod and_then = do
255 dep_mods = this_mod : map fst (moduleEnvElts (imp_dep_mods imports))
256 -- don't forget to include the current module!
258 mb_dep_pkgs = checkForPackageConflicts
259 dflags dep_mods (imp_dep_pkgs imports)
265 updGblEnv (\gbl -> gbl{ tcg_home_mods = mkHomeModules dep_mods })
270 %************************************************************************
272 Type-checking external-core modules
274 %************************************************************************
277 tcRnExtCore :: HscEnv
279 -> IO (Messages, Maybe ModGuts)
280 -- Nothing => some error occurred
282 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
283 -- The decls are IfaceDecls; all names are original names
284 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
286 initTc hsc_env ExtCoreFile this_mod $ do {
288 let { ldecls = map noLoc decls } ;
290 -- Deal with the type declarations; first bring their stuff
291 -- into scope, then rname them, then type check them
292 tcg_env <- importsFromLocalDecls (mkFakeGroup ldecls) ;
294 setGblEnv tcg_env $ do {
296 rn_decls <- rnTyClDecls ldecls ;
299 -- Dump trace of renaming part
300 rnDump (ppr rn_decls) ;
302 -- Typecheck them all together so that
303 -- any mutually recursive types are done right
304 tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails rn_decls) ;
305 -- Make the new type env available to stuff slurped from interface files
307 setGblEnv tcg_env $ do {
309 -- Now the core bindings
310 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
314 bndrs = bindersOfBinds core_binds ;
315 my_exports = mkNameSet (map idName bndrs) ;
316 -- ToDo: export the data types also?
318 final_type_env = extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
320 mod_guts = ModGuts { mg_module = this_mod,
322 mg_usages = [], -- ToDo: compute usage
323 mg_dir_imps = [], -- ??
324 mg_deps = noDependencies, -- ??
325 mg_home_mods = mkHomeModules [], -- ?? wrong!!
326 mg_exports = my_exports,
327 mg_types = final_type_env,
328 mg_insts = tcg_insts tcg_env,
330 mg_binds = core_binds,
333 mg_rdr_env = emptyGlobalRdrEnv,
334 mg_fix_env = emptyFixityEnv,
335 mg_deprecs = NoDeprecs,
339 tcCoreDump mod_guts ;
344 mkFakeGroup decls -- Rather clumsy; lots of unused fields
345 = emptyRdrGroup { hs_tyclds = decls }
349 %************************************************************************
351 Type-checking the top level of a module
353 %************************************************************************
356 tcRnSrcDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
357 -- Returns the variables free in the decls
358 -- Reason: solely to report unused imports and bindings
360 = do { -- Load the hi-boot interface for this module, if any
361 -- We do this now so that the boot_names can be passed
362 -- to tcTyAndClassDecls, because the boot_names are
363 -- automatically considered to be loop breakers
365 boot_iface <- tcHiBootIface mod ;
367 -- Do all the declarations
368 (tc_envs, lie) <- getLIE (tc_rn_src_decls boot_iface decls) ;
370 -- tcSimplifyTop deals with constant or ambiguous InstIds.
371 -- How could there be ambiguous ones? They can only arise if a
372 -- top-level decl falls under the monomorphism
373 -- restriction, and no subsequent decl instantiates its
374 -- type. (Usually, ambiguous type variables are resolved
375 -- during the generalisation step.)
376 traceTc (text "Tc8") ;
377 inst_binds <- setEnvs tc_envs (tcSimplifyTop lie) ;
378 -- Setting the global env exposes the instances to tcSimplifyTop
379 -- Setting the local env exposes the local Ids to tcSimplifyTop,
380 -- so that we get better error messages (monomorphism restriction)
382 -- Backsubstitution. This must be done last.
383 -- Even tcSimplifyTop may do some unification.
384 traceTc (text "Tc9") ;
385 let { (tcg_env, _) = tc_envs ;
386 TcGblEnv { tcg_type_env = type_env, tcg_binds = binds,
387 tcg_rules = rules, tcg_fords = fords } = tcg_env } ;
390 (bind_ids, binds', fords', rules') <- zonkTopDecls (binds `unionBags` inst_binds)
393 let { final_type_env = extendTypeEnvWithIds type_env bind_ids
394 ; tcg_env' = tcg_env { tcg_type_env = final_type_env,
397 tcg_fords = fords' } } ;
399 -- Make the new type env available to stuff slurped from interface files
400 writeMutVar (tcg_type_env_var tcg_env) final_type_env ;
402 -- Compare the hi-boot iface (if any) with the real thing
403 dfun_binds <- checkHiBootIface tcg_env' boot_iface ;
405 return (tcg_env' { tcg_binds = tcg_binds tcg_env' `unionBags` dfun_binds })
408 tc_rn_src_decls :: ModDetails -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
409 -- Loops around dealing with each top level inter-splice group
410 -- in turn, until it's dealt with the entire module
411 tc_rn_src_decls boot_details ds
412 = do { let { (first_group, group_tail) = findSplice ds } ;
413 -- If ds is [] we get ([], Nothing)
415 -- Type check the decls up to, but not including, the first splice
416 tc_envs@(tcg_env,tcl_env) <- tcRnGroup boot_details first_group ;
418 -- Bale out if errors; for example, error recovery when checking
419 -- the RHS of 'main' can mean that 'main' is not in the envt for
420 -- the subsequent checkMain test
425 -- If there is no splice, we're nearly done
427 Nothing -> do { -- Last thing: check for `main'
428 tcg_env <- checkMain ;
429 return (tcg_env, tcl_env)
432 -- If there's a splice, we must carry on
433 Just (SpliceDecl splice_expr, rest_ds) -> do {
435 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
438 -- Rename the splice expression, and get its supporting decls
439 (rn_splice_expr, splice_fvs) <- rnLExpr splice_expr ;
440 failIfErrsM ; -- Don't typecheck if renaming failed
442 -- Execute the splice
443 spliced_decls <- tcSpliceDecls rn_splice_expr ;
445 -- Glue them on the front of the remaining decls and loop
446 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
447 tc_rn_src_decls boot_details (spliced_decls ++ rest_ds)
452 %************************************************************************
454 Compiling hs-boot source files, and
455 comparing the hi-boot interface with the real thing
457 %************************************************************************
460 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
461 tcRnHsBootDecls decls
462 = do { let { (first_group, group_tail) = findSplice decls }
465 Just stuff -> spliceInHsBootErr stuff
468 -- Rename the declarations
469 ; (tcg_env, rn_group) <- rnTopSrcDecls first_group
470 ; setGblEnv tcg_env $ do {
472 -- Todo: check no foreign decls, no rules, no default decls
474 -- Typecheck type/class decls
475 ; traceTc (text "Tc2")
476 ; let tycl_decls = hs_tyclds rn_group
477 ; tcg_env <- checkNoErrs (tcTyAndClassDecls emptyModDetails tycl_decls)
478 ; setGblEnv tcg_env $ do {
480 -- Typecheck instance decls
481 ; traceTc (text "Tc3")
482 ; (tcg_env, inst_infos, _binds) <- tcInstDecls1 tycl_decls (hs_instds rn_group)
483 ; setGblEnv tcg_env $ do {
485 -- Typecheck value declarations
486 ; traceTc (text "Tc5")
487 ; val_ids <- tcHsBootSigs (hs_valds rn_group)
490 -- No simplification or zonking to do
491 ; traceTc (text "Tc7a")
492 ; gbl_env <- getGblEnv
494 -- Make the final type-env
495 -- Include the dfun_ids so that their type sigs get
496 -- are written into the interface file
497 ; let { type_env0 = tcg_type_env gbl_env
498 ; type_env1 = extendTypeEnvWithIds type_env0 val_ids
499 ; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
500 ; dfun_ids = map iDFunId inst_infos }
501 ; return (gbl_env { tcg_type_env = type_env2 })
504 spliceInHsBootErr (SpliceDecl (L loc _), _)
505 = addErrAt loc (ptext SLIT("Splices are not allowed in hs-boot files"))
508 Once we've typechecked the body of the module, we want to compare what
509 we've found (gathered in a TypeEnv) with the hi-boot details (if any).
512 checkHiBootIface :: TcGblEnv -> ModDetails -> TcM (LHsBinds Id)
513 -- Compare the hi-boot file for this module (if there is one)
514 -- with the type environment we've just come up with
515 -- In the common case where there is no hi-boot file, the list
516 -- of boot_names is empty.
518 -- The bindings we return give bindings for the dfuns defined in the
519 -- hs-boot file, such as $fbEqT = $fEqT
522 (TcGblEnv { tcg_insts = local_insts, tcg_type_env = local_type_env })
523 (ModDetails { md_insts = boot_insts, md_types = boot_type_env })
524 = do { mapM_ check_one (typeEnvElts boot_type_env)
525 ; dfun_binds <- mapM check_inst boot_insts
526 ; return (unionManyBags dfun_binds) }
532 = case lookupTypeEnv local_type_env name of
533 Nothing -> addErrTc (missingBootThing boot_thing)
534 Just real_thing -> check_thing boot_thing real_thing
536 name = getName boot_thing
538 no_check name = isWiredInName name -- No checking for wired-in names. In particular,
539 -- 'error' is handled by a rather gross hack
540 -- (see comments in GHC.Err.hs-boot)
541 || name `elem` dfun_names
542 dfun_names = map getName boot_insts
545 = case [dfun | inst <- local_insts,
546 let dfun = instanceDFunId inst,
547 idType dfun `tcEqType` boot_inst_ty ] of
548 [] -> do { addErrTc (instMisMatch boot_inst); return emptyBag }
549 (dfun:_) -> return (unitBag $ noLoc $ VarBind local_boot_dfun (nlHsVar dfun))
551 boot_dfun = instanceDFunId boot_inst
552 boot_inst_ty = idType boot_dfun
553 local_boot_dfun = mkExportedLocalId (idName boot_dfun) boot_inst_ty
556 check_thing (ATyCon boot_tc) (ATyCon real_tc)
557 | isSynTyCon boot_tc && isSynTyCon real_tc,
558 defn1 `tcEqType` substTyWith tvs2 (mkTyVarTys tvs1) defn2
561 | tyConKind boot_tc == tyConKind real_tc
564 (tvs1, defn1) = synTyConDefn boot_tc
565 (tvs2, defn2) = synTyConDefn boot_tc
567 check_thing (AnId boot_id) (AnId real_id)
568 | idType boot_id `tcEqType` idType real_id
571 check_thing (ADataCon dc1) (ADataCon dc2)
572 | idType (dataConWrapId dc1) `tcEqType` idType (dataConWrapId dc2)
575 -- Can't declare a class in a hi-boot file
577 check_thing boot_thing real_thing -- Default case; failure
578 = addErrAt (srcLocSpan (getSrcLoc real_thing))
579 (bootMisMatch real_thing)
582 missingBootThing thing
583 = ppr thing <+> ptext SLIT("is defined in the hs-boot file, but not in the module")
585 = ppr thing <+> ptext SLIT("has conflicting definitions in the module and its hs-boot file")
588 2 (ptext SLIT("is defined in the hs-boot file, but not in the module"))
592 %************************************************************************
594 Type-checking the top level of a module
596 %************************************************************************
598 tcRnGroup takes a bunch of top-level source-code declarations, and
600 * gets supporting declarations from interface files
603 * and augments the TcGblEnv with the results
605 In Template Haskell it may be called repeatedly for each group of
606 declarations. It expects there to be an incoming TcGblEnv in the
607 monad; it augments it and returns the new TcGblEnv.
610 tcRnGroup :: ModDetails -> HsGroup RdrName -> TcM (TcGblEnv, TcLclEnv)
611 -- Returns the variables free in the decls, for unused-binding reporting
612 tcRnGroup boot_details decls
613 = do { -- Rename the declarations
614 (tcg_env, rn_decls) <- rnTopSrcDecls decls ;
615 setGblEnv tcg_env $ do {
617 -- Typecheck the declarations
618 tcTopSrcDecls boot_details rn_decls
621 ------------------------------------------------
622 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
624 = do { -- Bring top level binders into scope
625 tcg_env <- importsFromLocalDecls group ;
626 setGblEnv tcg_env $ do {
628 failIfErrsM ; -- No point in continuing if (say) we have duplicate declarations
630 -- Rename the source decls
631 (tcg_env, rn_decls) <- rnSrcDecls group ;
634 -- save the renamed syntax, if we want it
636 | Just grp <- tcg_rn_decls tcg_env
637 = tcg_env{ tcg_rn_decls = Just (appendGroups grp rn_decls) }
641 -- Dump trace of renaming part
642 rnDump (ppr rn_decls) ;
644 return (tcg_env', rn_decls)
647 ------------------------------------------------
648 tcTopSrcDecls :: ModDetails -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
649 tcTopSrcDecls boot_details
650 (HsGroup { hs_tyclds = tycl_decls,
651 hs_instds = inst_decls,
652 hs_fords = foreign_decls,
653 hs_defds = default_decls,
654 hs_ruleds = rule_decls,
655 hs_valds = val_binds })
656 = do { -- Type-check the type and class decls, and all imported decls
657 -- The latter come in via tycl_decls
658 traceTc (text "Tc2") ;
660 tcg_env <- checkNoErrs (tcTyAndClassDecls boot_details tycl_decls) ;
661 -- tcTyAndClassDecls recovers internally, but if anything gave rise to
662 -- an error we'd better stop now, to avoid a cascade
664 -- Make these type and class decls available to stuff slurped from interface files
665 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
668 setGblEnv tcg_env $ do {
669 -- Source-language instances, including derivings,
670 -- and import the supporting declarations
671 traceTc (text "Tc3") ;
672 (tcg_env, inst_infos, deriv_binds) <- tcInstDecls1 tycl_decls inst_decls ;
673 setGblEnv tcg_env $ do {
675 -- Foreign import declarations next. No zonking necessary
676 -- here; we can tuck them straight into the global environment.
677 traceTc (text "Tc4") ;
678 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
679 tcExtendGlobalValEnv fi_ids $ do {
681 -- Default declarations
682 traceTc (text "Tc4a") ;
683 default_tys <- tcDefaults default_decls ;
684 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
686 -- Value declarations next
687 -- We also typecheck any extra binds that came out
688 -- of the "deriving" process (deriv_binds)
689 traceTc (text "Tc5") ;
690 (tc_val_binds, tcl_env) <- tcTopBinds (val_binds `plusHsValBinds` deriv_binds) ;
691 setLclTypeEnv tcl_env $ do {
693 -- Second pass over class and instance declarations,
694 traceTc (text "Tc6") ;
695 (inst_binds, tcl_env) <- tcInstDecls2 tycl_decls inst_infos ;
696 showLIE (text "after instDecls2") ;
699 -- They need to be zonked, so we return them
700 traceTc (text "Tc7") ;
701 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
704 rules <- tcRules rule_decls ;
707 traceTc (text "Tc7a") ;
708 tcg_env <- getGblEnv ;
709 let { all_binds = tc_val_binds `unionBags`
710 inst_binds `unionBags`
713 -- Extend the GblEnv with the (as yet un-zonked)
714 -- bindings, rules, foreign decls
715 tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds,
716 tcg_rules = tcg_rules tcg_env ++ rules,
717 tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
718 return (tcg_env', tcl_env)
723 %************************************************************************
727 %************************************************************************
730 checkMain :: TcM TcGblEnv
731 -- If we are in module Main, check that 'main' is defined.
733 = do { ghci_mode <- getGhciMode ;
734 tcg_env <- getGblEnv ;
736 let { main_mod = mainModIs dflags ;
737 main_fn = case mainFunIs dflags of {
738 Just fn -> mkRdrUnqual (mkVarOccFS (mkFastString fn)) ;
739 Nothing -> main_RDR_Unqual } } ;
741 check_main ghci_mode tcg_env main_mod main_fn
745 check_main ghci_mode tcg_env main_mod main_fn
747 = traceTc (text "checkMain not" <+> ppr main_mod <+> ppr mod) >>
751 = addErrCtxt mainCtxt $
752 do { mb_main <- lookupSrcOcc_maybe main_fn
753 -- Check that 'main' is in scope
754 -- It might be imported from another module!
756 Nothing -> do { traceTc (text "checkMain fail" <+> ppr main_mod <+> ppr main_fn)
760 { traceTc (text "checkMain found" <+> ppr main_mod <+> ppr main_fn)
761 ; let { rhs = nlHsApp (nlHsVar runMainIOName) (nlHsVar main_name) }
762 -- :Main.main :: IO () = runMainIO main
764 ; (main_expr, ty) <- setSrcSpan (srcLocSpan (getSrcLoc main_name)) $
767 -- The function that the RTS invokes is always :Main.main,
768 -- which we call root_main_id.
769 -- (Because GHC allows the user to have a module not called
770 -- Main as the main module, we can't rely on the main function
771 -- being called "Main.main". That's why root_main_id has a fixed
773 -- We also make root_main_id an implicit Id, by making main_name
774 -- its parent (hence (Just main_name)). That has the effect
775 -- of preventing its type and unfolding from getting out into
776 -- the interface file. Otherwise we can end up with two defns
777 -- for 'main' in the interface file!
779 ; let { root_main_name = mkExternalName rootMainKey rOOT_MAIN
780 (mkVarOccFS FSLIT("main"))
781 (Just main_name) (getSrcLoc main_name)
782 ; root_main_id = mkExportedLocalId root_main_name ty
783 ; main_bind = noLoc (VarBind root_main_id main_expr) }
785 ; return (tcg_env { tcg_binds = tcg_binds tcg_env
787 tcg_dus = tcg_dus tcg_env
788 `plusDU` usesOnly (unitFV main_name)
789 -- Record the use of 'main', so that we don't
790 -- complain about it being defined but not used
794 mod = tcg_mod tcg_env
796 complain_no_main | ghci_mode == Interactive = return ()
797 | otherwise = failWithTc noMainMsg
798 -- In interactive mode, don't worry about the absence of 'main'
799 -- In other modes, fail altogether, so that we don't go on
800 -- and complain a second time when processing the export list.
802 mainCtxt = ptext SLIT("When checking the type of the main function") <+> quotes (ppr main_fn)
803 noMainMsg = ptext SLIT("The main function") <+> quotes (ppr main_fn)
804 <+> ptext SLIT("is not defined in module") <+> quotes (ppr main_mod)
807 %*********************************************************
811 %*********************************************************
815 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
816 setInteractiveContext hsc_env icxt thing_inside
818 -- Initialise the tcg_inst_env with instances
819 -- from all home modules. This mimics the more selective
820 -- call to hptInstances in tcRnModule
821 dfuns = hptInstances hsc_env (\mod -> True)
823 updGblEnv (\env -> env {
824 tcg_rdr_env = ic_rn_gbl_env icxt,
825 tcg_type_env = ic_type_env icxt,
826 tcg_inst_env = extendInstEnvList (tcg_inst_env env) dfuns }) $
828 updLclEnv (\env -> env { tcl_rdr = ic_rn_local_env icxt }) $
830 do { traceTc (text "setIC" <+> ppr (ic_type_env icxt))
837 -> InteractiveContext
839 -> IO (Maybe (InteractiveContext, [Name], LHsExpr Id))
840 -- The returned [Name] is the same as the input except for
841 -- ExprStmt, in which case the returned [Name] is [itName]
843 -- The returned TypecheckedHsExpr is of type IO [ () ],
844 -- a list of the bound values, coerced to ().
846 tcRnStmt hsc_env ictxt rdr_stmt
847 = initTcPrintErrors hsc_env iNTERACTIVE $
848 setInteractiveContext hsc_env ictxt $ do {
850 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
851 (([rn_stmt], _), fvs) <- rnStmts DoExpr [rdr_stmt] (return ((), emptyFVs)) ;
852 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
855 -- The real work is done here
856 (bound_ids, tc_expr) <- mkPlan rn_stmt ;
857 zonked_expr <- zonkTopLExpr tc_expr ;
858 zonked_ids <- zonkTopBndrs bound_ids ;
860 -- None of the Ids should be of unboxed type, because we
861 -- cast them all to HValues in the end!
862 mappM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
864 traceTc (text "tcs 1") ;
865 let { -- (a) Make all the bound ids "global" ids, now that
866 -- they're notionally top-level bindings. This is
867 -- important: otherwise when we come to compile an expression
868 -- using these ids later, the byte code generator will consider
869 -- the occurrences to be free rather than global.
871 -- (b) Tidy their types; this is important, because :info may
872 -- ask to look at them, and :info expects the things it looks
873 -- up to have tidy types
874 global_ids = map globaliseAndTidy zonked_ids ;
876 -- Update the interactive context
877 rn_env = ic_rn_local_env ictxt ;
878 type_env = ic_type_env ictxt ;
880 bound_names = map idName global_ids ;
881 new_rn_env = extendLocalRdrEnv rn_env bound_names ;
883 -- Remove any shadowed bindings from the type_env;
884 -- they are inaccessible but might, I suppose, cause
885 -- a space leak if we leave them there
886 shadowed = [ n | name <- bound_names,
887 let rdr_name = mkRdrUnqual (nameOccName name),
888 Just n <- [lookupLocalRdrEnv rn_env rdr_name] ] ;
890 filtered_type_env = delListFromNameEnv type_env shadowed ;
891 new_type_env = extendTypeEnvWithIds filtered_type_env global_ids ;
893 new_ic = ictxt { ic_rn_local_env = new_rn_env,
894 ic_type_env = new_type_env }
897 dumpOptTcRn Opt_D_dump_tc
898 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
899 text "Typechecked expr" <+> ppr zonked_expr]) ;
901 returnM (new_ic, bound_names, zonked_expr)
904 bad_unboxed id = addErr (sep [ptext SLIT("GHCi can't bind a variable of unlifted type:"),
905 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
907 globaliseAndTidy :: Id -> Id
909 -- Give the Id a Global Name, and tidy its type
910 = setIdType (globaliseId VanillaGlobal id) tidy_type
912 tidy_type = tidyTopType (idType id)
915 Here is the grand plan, implemented in tcUserStmt
917 What you type The IO [HValue] that hscStmt returns
918 ------------- ------------------------------------
919 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
922 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
925 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
926 [NB: result not printed] bindings: [it]
928 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
929 result showable) bindings: [it]
931 expr (of non-IO type,
932 result not showable) ==> error
936 ---------------------------
937 type PlanResult = ([Id], LHsExpr Id)
938 type Plan = TcM PlanResult
940 runPlans :: [Plan] -> TcM PlanResult
941 -- Try the plans in order. If one fails (by raising an exn), try the next.
942 -- If one succeeds, take it.
943 runPlans [] = panic "runPlans"
945 runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
948 mkPlan :: LStmt Name -> TcM PlanResult
949 mkPlan (L loc (ExprStmt expr _ _)) -- An expression typed at the prompt
950 = do { uniq <- newUnique -- is treated very specially
951 ; let fresh_it = itName uniq
952 the_bind = L loc $ mkFunBind (L loc fresh_it) matches
953 matches = [mkMatch [] expr emptyLocalBinds]
954 let_stmt = L loc $ LetStmt (HsValBinds (ValBindsOut [(NonRecursive,unitBag the_bind)] []))
955 bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
956 (HsVar bindIOName) noSyntaxExpr
957 print_it = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
958 (HsVar thenIOName) placeHolderType
961 -- [it <- e; print it] but not if it::()
963 -- [let it = e; print it]
964 ; runPlans [ -- Plan A
965 do { stuff@([it_id], _) <- tcGhciStmts [bind_stmt, print_it]
966 ; it_ty <- zonkTcType (idType it_id)
967 ; ifM (isUnitTy it_ty) failM
970 -- Plan B; a naked bind statment
971 tcGhciStmts [bind_stmt],
973 -- Plan C; check that the let-binding is typeable all by itself.
974 -- If not, fail; if so, try to print it.
975 -- The two-step process avoids getting two errors: one from
976 -- the expression itself, and one from the 'print it' part
977 -- This two-step story is very clunky, alas
978 do { checkNoErrs (tcGhciStmts [let_stmt])
979 --- checkNoErrs defeats the error recovery of let-bindings
980 ; tcGhciStmts [let_stmt, print_it] }
983 mkPlan stmt@(L loc (BindStmt {}))
984 | [L _ v] <- collectLStmtBinders stmt -- One binder, for a bind stmt
985 = do { let print_v = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
986 (HsVar thenIOName) placeHolderType
988 -- [stmt; print v] but not if v::()
990 ; runPlans [do { stuff@([v_id], _) <- tcGhciStmts [stmt, print_v]
991 ; v_ty <- zonkTcType (idType v_id)
992 ; ifM (isUnitTy v_ty || not (isTauTy v_ty)) failM
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] ;
1010 names = map unLoc (collectLStmtsBinders stmts) ;
1012 -- mk_return builds the expression
1013 -- returnIO @ [()] [coerce () x, .., coerce () z]
1015 -- Despite the inconvenience of building the type applications etc,
1016 -- this *has* to be done in type-annotated post-typecheck form
1017 -- because we are going to return a list of *polymorphic* values
1018 -- coerced to type (). If we built a *source* stmt
1019 -- return [coerce x, ..., coerce z]
1020 -- then the type checker would instantiate x..z, and we wouldn't
1021 -- get their *polymorphic* values. (And we'd get ambiguity errs
1022 -- if they were overloaded, since they aren't applied to anything.)
1023 mk_return ids = nlHsApp (noLoc $ TyApp (nlHsVar ret_id) [ret_ty])
1024 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
1025 mk_item id = nlHsApp (noLoc $ TyApp (nlHsVar unsafeCoerceId) [idType id, unitTy])
1029 -- OK, we're ready to typecheck the stmts
1030 traceTc (text "tcs 2") ;
1031 ((tc_stmts, ids), lie) <- getLIE $
1032 tcStmts DoExpr (tcDoStmt io_ty) stmts io_ret_ty $ \ _ ->
1033 mappM tcLookupId names ;
1034 -- Look up the names right in the middle,
1035 -- where they will all be in scope
1037 -- Simplify the context
1038 const_binds <- checkNoErrs (tcSimplifyInteractive lie) ;
1039 -- checkNoErrs ensures that the plan fails if context redn fails
1041 return (ids, mkHsDictLet const_binds $
1042 noLoc (HsDo DoExpr tc_stmts (mk_return ids) io_ret_ty))
1047 tcRnExpr just finds the type of an expression
1051 -> InteractiveContext
1054 tcRnExpr hsc_env ictxt rdr_expr
1055 = initTcPrintErrors hsc_env iNTERACTIVE $
1056 setInteractiveContext hsc_env ictxt $ do {
1058 (rn_expr, fvs) <- rnLExpr rdr_expr ;
1061 -- Now typecheck the expression;
1062 -- it might have a rank-2 type (e.g. :t runST)
1063 ((tc_expr, res_ty), lie) <- getLIE (tcInferRho rn_expr) ;
1064 ((qtvs, _, dict_ids), lie_top) <- getLIE (tcSimplifyInfer smpl_doc (tyVarsOfType res_ty) lie) ;
1065 tcSimplifyInteractive lie_top ;
1066 qtvs' <- mappM zonkQuantifiedTyVar qtvs ;
1068 let { all_expr_ty = mkForAllTys qtvs' $
1069 mkFunTys (map idType dict_ids) $
1071 zonkTcType all_expr_ty
1074 smpl_doc = ptext SLIT("main expression")
1077 tcRnType just finds the kind of a type
1081 -> InteractiveContext
1084 tcRnType hsc_env ictxt rdr_type
1085 = initTcPrintErrors hsc_env iNTERACTIVE $
1086 setInteractiveContext hsc_env ictxt $ do {
1088 rn_type <- rnLHsType doc rdr_type ;
1091 -- Now kind-check the type
1092 (ty', kind) <- kcHsType rn_type ;
1096 doc = ptext SLIT("In GHCi input")
1102 %************************************************************************
1104 More GHCi stuff, to do with browsing and getting info
1106 %************************************************************************
1110 -- ASSUMES that the module is either in the HomePackageTable or is
1111 -- a package module with an interface on disk. If neither of these is
1112 -- true, then the result will be an error indicating the interface
1113 -- could not be found.
1114 getModuleExports :: HscEnv -> Module -> IO (Messages, Maybe NameSet)
1115 getModuleExports hsc_env mod
1116 = initTc hsc_env HsSrcFile iNTERACTIVE (tcGetModuleExports mod)
1118 tcGetModuleExports :: Module -> TcM NameSet
1119 tcGetModuleExports mod = do
1120 iface <- load_iface mod
1121 loadOrphanModules (dep_orphs (mi_deps iface))
1122 -- Load any orphan-module interfaces,
1123 -- so their instances are visible
1124 ifaceExportNames (mi_exports iface)
1126 load_iface mod = loadSrcInterface doc mod False {- Not boot iface -}
1128 doc = ptext SLIT("context for compiling statements")
1131 tcRnLookupRdrName :: HscEnv -> RdrName -> IO (Maybe [Name])
1132 tcRnLookupRdrName hsc_env rdr_name
1133 = initTcPrintErrors hsc_env iNTERACTIVE $
1134 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1135 lookup_rdr_name rdr_name
1137 lookup_rdr_name rdr_name = do {
1138 -- If the identifier is a constructor (begins with an
1139 -- upper-case letter), then we need to consider both
1140 -- constructor and type class identifiers.
1141 let { rdr_names = dataTcOccs rdr_name } ;
1143 -- results :: [Either Messages Name]
1144 results <- mapM (tryTcErrs . lookupOccRn) rdr_names ;
1146 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1147 -- The successful lookups will be (Just name)
1148 let { (warns_s, good_names) = unzip [ (msgs, name)
1149 | (msgs, Just name) <- results] ;
1150 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1152 -- Fail if nothing good happened, else add warnings
1153 if null good_names then
1154 -- No lookup succeeded, so
1155 -- pick the first error message and report it
1156 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1157 -- while the other is "X is not in scope",
1158 -- we definitely want the former; but we might pick the latter
1159 do { addMessages (head errs_s) ; failM }
1160 else -- Add deprecation warnings
1161 mapM_ addMessages warns_s ;
1167 tcRnLookupName :: HscEnv -> Name -> IO (Maybe TyThing)
1168 tcRnLookupName hsc_env name
1169 = initTcPrintErrors hsc_env iNTERACTIVE $
1170 setInteractiveContext hsc_env (hsc_IC hsc_env) $
1174 tcRnGetInfo :: HscEnv
1176 -> IO (Maybe (TyThing, Fixity, [Instance]))
1178 -- Used to implemnent :info in GHCi
1180 -- Look up a RdrName and return all the TyThings it might be
1181 -- A capitalised RdrName is given to us in the DataName namespace,
1182 -- but we want to treat it as *both* a data constructor
1183 -- *and* as a type or class constructor;
1184 -- hence the call to dataTcOccs, and we return up to two results
1185 tcRnGetInfo hsc_env name
1186 = initTcPrintErrors hsc_env iNTERACTIVE $
1187 let ictxt = hsc_IC hsc_env in
1188 setInteractiveContext hsc_env ictxt $ do
1190 -- Load the interface for all unqualified types and classes
1191 -- That way we will find all the instance declarations
1192 -- (Packages have not orphan modules, and we assume that
1193 -- in the home package all relevant modules are loaded.)
1194 loadUnqualIfaces ictxt
1196 thing <- tcLookupGlobal name
1197 fixity <- lookupFixityRn name
1198 ispecs <- lookupInsts (icPrintUnqual ictxt) thing
1199 return (thing, fixity, ispecs)
1202 lookupInsts :: PrintUnqualified -> TyThing -> TcM [Instance]
1203 -- Filter the instances by the ones whose tycons (or clases resp)
1204 -- are in scope unqualified. Otherwise we list a whole lot too many!
1205 lookupInsts print_unqual (AClass cls)
1206 = do { inst_envs <- tcGetInstEnvs
1208 | ispec <- classInstances inst_envs cls
1209 , plausibleDFun print_unqual (instanceDFunId ispec) ] }
1211 lookupInsts print_unqual (ATyCon tc)
1212 = do { eps <- getEps -- Load all instances for all classes that are
1213 -- in the type environment (which are all the ones
1214 -- we've seen in any interface file so far)
1215 ; (pkg_ie, home_ie) <- tcGetInstEnvs -- Search all
1217 | ispec <- instEnvElts home_ie ++ instEnvElts pkg_ie
1218 , let dfun = instanceDFunId ispec
1220 , plausibleDFun print_unqual dfun ] }
1222 relevant df = tc_name `elemNameSet` tyClsNamesOfDFunHead (idType df)
1223 tc_name = tyConName tc
1225 lookupInsts print_unqual other = return []
1227 plausibleDFun print_unqual dfun -- Dfun involving only names that print unqualified
1228 = all ok (nameSetToList (tyClsNamesOfType (idType dfun)))
1230 ok name | isBuiltInSyntax name = True
1231 | isExternalName name = print_unqual (nameModule name) (nameOccName name)
1234 loadUnqualIfaces :: InteractiveContext -> TcM ()
1235 -- Load the home module for everything that is in scope unqualified
1236 -- This is so that we can accurately report the instances for
1238 loadUnqualIfaces ictxt
1240 mapM_ (loadSysInterface doc) (moduleSetElts (mkModuleSet unqual_mods))
1242 unqual_mods = [ nameModule name
1243 | gre <- globalRdrEnvElts (ic_rn_gbl_env ictxt),
1244 let name = gre_name gre,
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 (moduleEnvElts (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)))]