2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[TcModule]{Typechecking a whole module}
9 mkExportEnv, getModuleContents, tcRnStmt,
10 tcRnGetInfo, tcRnExpr, tcRnType,
17 #include "HsVersions.h"
21 import {-# SOURCE #-} TcSplice ( tcSpliceDecls )
24 import CmdLineOpts ( DynFlag(..), opt_PprStyle_Debug, dopt )
25 import Packages ( moduleToPackageConfig, mkPackageId, package,
27 import DriverState ( v_MainModIs, v_MainFunIs )
28 import HsSyn ( HsModule(..), HsExtCore(..), HsGroup(..), LHsDecl, SpliceDecl(..), HsBind(..),
29 nlHsApp, nlHsVar, pprLHsBinds )
30 import RdrHsSyn ( findSplice )
32 import PrelNames ( runMainIOName, rootMainName, mAIN,
34 import RdrName ( RdrName, mkRdrUnqual, emptyGlobalRdrEnv,
36 import TcHsSyn ( zonkTopDecls )
37 import TcExpr ( tcInferRho )
39 import TcType ( tidyTopType, tcEqType, mkTyVarTys, substTyWith )
40 import Inst ( showLIE )
41 import InstEnv ( extendInstEnvList )
42 import TcBinds ( tcTopBinds, tcHsBootSigs )
43 import TcDefaults ( tcDefaults )
44 import TcEnv ( tcExtendGlobalValEnv )
45 import TcRules ( tcRules )
46 import TcForeign ( tcForeignImports, tcForeignExports )
47 import TcInstDcls ( tcInstDecls1, tcInstDecls2 )
48 import TcIface ( tcExtCoreBindings )
49 import TcSimplify ( tcSimplifyTop )
50 import TcTyClsDecls ( tcTyAndClassDecls )
51 import LoadIface ( loadOrphanModules, loadHiBootInterface )
52 import RnNames ( importsFromLocalDecls, rnImports, exportsFromAvail,
53 reportUnusedNames, reportDeprecations )
54 import RnEnv ( lookupSrcOcc_maybe )
55 import RnSource ( rnSrcDecls, rnTyClDecls, checkModDeprec )
56 import PprCore ( pprIdRules, pprCoreBindings )
57 import CoreSyn ( IdCoreRule, bindersOfBinds )
58 import DataCon ( dataConWrapId )
59 import ErrUtils ( Messages, mkDumpDoc, showPass )
60 import Id ( mkExportedLocalId, isLocalId, idName, idType )
62 import VarEnv ( varEnvElts )
63 import Module ( Module, ModuleEnv, mkModule, moduleEnvElts, lookupModuleEnv )
64 import OccName ( mkVarOcc )
65 import Name ( Name, isExternalName, getSrcLoc, getOccName, isWiredInName )
67 import TyCon ( tyConHasGenerics, isSynTyCon, getSynTyConDefn, tyConKind )
68 import SrcLoc ( srcLocSpan, Located(..), noLoc )
69 import DriverPhases ( HscSource(..), isHsBoot )
70 import HscTypes ( ModGuts(..), HscEnv(..), ExternalPackageState(..),
71 GhciMode(..), IsBootInterface, noDependencies,
72 Deprecs( NoDeprecs ), plusDeprecs,
73 ForeignStubs(NoStubs), TyThing(..),
74 TypeEnv, lookupTypeEnv, hptInstances, lookupType,
75 extendTypeEnvWithIds, typeEnvIds, typeEnvTyCons,
81 import HsSyn ( HsStmtContext(..), Stmt(..), HsExpr(..), HsBindGroup(..),
82 LStmt, LHsExpr, LHsType, mkMatchGroup,
83 collectStmtsBinders, mkSimpleMatch,
84 nlLetStmt, nlExprStmt, nlBindStmt, nlResultStmt, nlVarPat )
85 import RdrName ( GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
86 Provenance(..), ImportSpec(..),
87 lookupLocalRdrEnv, extendLocalRdrEnv )
88 import RnSource ( addTcgDUs )
89 import TcHsSyn ( mkHsLet, zonkTopLExpr, zonkTopBndrs )
90 import TcHsType ( kcHsType )
91 import TcExpr ( tcCheckRho )
92 import TcIface ( loadImportedInsts )
93 import TcMType ( zonkTcType, zonkQuantifiedTyVar )
94 import TcUnify ( unifyTyConApp )
95 import TcMatches ( tcStmtsAndThen, TcStmtCtxt(..) )
96 import TcSimplify ( tcSimplifyInteractive, tcSimplifyInfer )
97 import TcType ( Type, mkForAllTys, mkFunTys, mkTyConApp, tyVarsOfType,
98 isUnLiftedType, tyClsNamesOfDFunHead )
99 import TcEnv ( tcLookupTyCon, tcLookupId, tcLookupGlobal )
100 import RnTypes ( rnLHsType )
101 import Inst ( tcStdSyntaxName, tcGetInstEnvs )
102 import InstEnv ( classInstances, instEnvElts )
103 import RnExpr ( rnStmts, rnLExpr )
104 import RnNames ( exportsToAvails )
105 import LoadIface ( loadSrcInterface, ifaceInstGates )
106 import IfaceSyn ( IfaceDecl(..), IfaceClassOp(..), IfaceConDecl(..),
107 IfaceExtName(..), IfaceConDecls(..), IfaceInst(..),
108 tyThingToIfaceDecl, dfunToIfaceInst )
109 import IfaceType ( IfaceTyCon(..), interactiveExtNameFun, isLocalIfaceExtName )
110 import IfaceEnv ( lookupOrig )
111 import RnEnv ( lookupOccRn, dataTcOccs, lookupFixityRn )
112 import Id ( Id, isImplicitId, setIdType, globalIdDetails )
113 import MkId ( unsafeCoerceId )
114 import DataCon ( dataConTyCon )
115 import TyCon ( tyConName )
116 import TysWiredIn ( mkListTy, unitTy )
117 import IdInfo ( GlobalIdDetails(..) )
118 import SrcLoc ( interactiveSrcLoc, unLoc )
120 import Var ( globaliseId )
121 import Name ( nameOccName )
122 import NameEnv ( delListFromNameEnv )
123 import PrelNames ( iNTERACTIVE, ioTyConName, printName, monadNames, itName, returnIOName )
124 import HscTypes ( InteractiveContext(..), HomeModInfo(..), typeEnvElts, typeEnvClasses,
125 availNames, availName, ModIface(..), icPrintUnqual,
126 ModDetails(..), Dependencies(..) )
127 import BasicTypes ( RecFlag(..), Fixity )
128 import Bag ( unitBag )
129 import ListSetOps ( removeDups )
130 import Panic ( ghcError, GhcException(..) )
131 import SrcLoc ( SrcLoc )
134 import FastString ( mkFastString )
135 import Util ( sortLe )
136 import Bag ( unionBags, snocBag )
138 import Maybe ( isJust )
143 %************************************************************************
145 Typecheck and rename a module
147 %************************************************************************
153 -> Located (HsModule RdrName)
154 -> IO (Messages, Maybe TcGblEnv)
156 tcRnModule hsc_env hsc_src (L loc (HsModule maybe_mod export_ies
157 import_decls local_decls mod_deprec))
158 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
160 let { this_mod = case maybe_mod of
161 Nothing -> mAIN -- 'module M where' is omitted
162 Just (L _ mod) -> mod } ; -- The normal case
164 initTc hsc_env hsc_src this_mod $
167 checkForPackageModule (hsc_dflags hsc_env) this_mod;
169 -- Deal with imports; sets tcg_rdr_env, tcg_imports
170 (rdr_env, imports) <- rnImports import_decls ;
172 let { dep_mods :: ModuleEnv (Module, IsBootInterface)
173 ; dep_mods = imp_dep_mods imports
175 ; is_dep_mod :: Module -> Bool
176 ; is_dep_mod mod = case lookupModuleEnv dep_mods mod of
178 Just (_, is_boot) -> not is_boot
179 ; home_insts = hptInstances hsc_env is_dep_mod
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 = rdr_env,
190 tcg_inst_env = extendInstEnvList (tcg_inst_env gbl) home_insts,
191 tcg_imports = tcg_imports gbl `plusImportAvails` imports })
194 traceRn (text "rn1" <+> ppr (imp_dep_mods imports)) ;
195 -- Fail if there are any errors so far
196 -- The error printing (if needed) takes advantage
197 -- of the tcg_env we have now set
200 -- Load any orphan-module interfaces, so that
201 -- their rules and instance decls will be found
202 loadOrphanModules (imp_orphs imports) ;
204 traceRn (text "rn1a") ;
205 -- Rename and type check the declarations
206 tcg_env <- if isHsBoot hsc_src then
207 tcRnHsBootDecls local_decls
209 tcRnSrcDecls local_decls ;
210 setGblEnv tcg_env $ do {
212 traceRn (text "rn3") ;
214 -- Report the use of any deprecated things
215 -- We do this before processsing the export list so
216 -- that we don't bleat about re-exporting a deprecated
217 -- thing (especially via 'module Foo' export item)
218 -- Only uses in the body of the module are complained about
219 reportDeprecations tcg_env ;
221 -- Process the export list
222 exports <- exportsFromAvail (isJust maybe_mod) export_ies ;
224 -- Check whether the entire module is deprecated
225 -- This happens only once per module
226 let { mod_deprecs = checkModDeprec mod_deprec } ;
228 -- Add exports and deprecations to envt
229 let { final_env = tcg_env { tcg_exports = exports,
230 tcg_dus = tcg_dus tcg_env `plusDU` usesOnly exports,
231 tcg_deprecs = tcg_deprecs tcg_env `plusDeprecs`
233 -- A module deprecation over-rides the earlier ones
236 -- Report unused names
237 reportUnusedNames export_ies final_env ;
239 -- Dump output and return
244 -- This is really a sanity check that the user has given -package-name
245 -- if necessary. -package-name is only necessary when the package database
246 -- already contains the current package, because then we can't tell
247 -- whether a given module is in the current package or not, without knowing
248 -- the name of the current package.
249 checkForPackageModule dflags this_mod
250 | not (isHomeModule dflags this_mod),
251 Just (pkg,_) <- moduleToPackageConfig dflags this_mod =
253 ppr_pkg = ppr (mkPackageId (package pkg))
255 addErr (ptext SLIT("Module") <+> quotes (ppr this_mod) <+>
256 ptext SLIT("is a member of package") <+> ppr_pkg <> char '.' $$
257 ptext SLIT("To compile this module, please use -ignore-package") <+> ppr_pkg <> char '.')
258 | otherwise = return ()
262 %************************************************************************
264 Type-checking external-core modules
266 %************************************************************************
269 tcRnExtCore :: HscEnv
271 -> IO (Messages, Maybe ModGuts)
272 -- Nothing => some error occurred
274 tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds)
275 -- The decls are IfaceDecls; all names are original names
276 = do { showPass (hsc_dflags hsc_env) "Renamer/typechecker" ;
278 initTc hsc_env ExtCoreFile this_mod $ do {
280 let { ldecls = map noLoc decls } ;
282 -- Deal with the type declarations; first bring their stuff
283 -- into scope, then rname them, then type check them
284 (rdr_env, imports) <- importsFromLocalDecls (mkFakeGroup ldecls) ;
286 updGblEnv (\gbl -> gbl { tcg_rdr_env = rdr_env `plusGlobalRdrEnv` tcg_rdr_env gbl,
287 tcg_imports = imports `plusImportAvails` tcg_imports gbl })
290 rn_decls <- rnTyClDecls ldecls ;
293 -- Dump trace of renaming part
294 rnDump (ppr rn_decls) ;
296 -- Typecheck them all together so that
297 -- any mutually recursive types are done right
298 tcg_env <- checkNoErrs (tcTyAndClassDecls [{- no boot names -}] rn_decls) ;
299 -- Make the new type env available to stuff slurped from interface files
301 setGblEnv tcg_env $ do {
303 -- Now the core bindings
304 core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
308 bndrs = bindersOfBinds core_binds ;
309 my_exports = mkNameSet (map idName bndrs) ;
310 -- ToDo: export the data types also?
312 final_type_env = extendTypeEnvWithIds (tcg_type_env tcg_env) bndrs ;
314 mod_guts = ModGuts { mg_module = this_mod,
316 mg_usages = [], -- ToDo: compute usage
317 mg_dir_imps = [], -- ??
318 mg_deps = noDependencies, -- ??
319 mg_exports = my_exports,
320 mg_types = final_type_env,
321 mg_insts = tcg_insts tcg_env,
323 mg_binds = core_binds,
326 mg_rdr_env = emptyGlobalRdrEnv,
327 mg_fix_env = emptyFixityEnv,
328 mg_deprecs = NoDeprecs,
332 tcCoreDump mod_guts ;
337 mkFakeGroup decls -- Rather clumsy; lots of unused fields
338 = HsGroup { hs_tyclds = decls, -- This is the one we want
339 hs_valds = [], hs_fords = [],
340 hs_instds = [], hs_fixds = [], hs_depds = [],
341 hs_ruleds = [], hs_defds = [] }
345 %************************************************************************
347 Type-checking the top level of a module
349 %************************************************************************
352 tcRnSrcDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
353 -- Returns the variables free in the decls
354 -- Reason: solely to report unused imports and bindings
356 = do { -- Load the hi-boot interface for this module, if any
357 -- We do this now so that the boot_names can be passed
358 -- to tcTyAndClassDecls, because the boot_names are
359 -- automatically considered to be loop breakers
360 boot_names <- loadHiBootInterface ;
362 -- Do all the declarations
363 (tc_envs, lie) <- getLIE (tc_rn_src_decls boot_names decls) ;
365 -- tcSimplifyTop deals with constant or ambiguous InstIds.
366 -- How could there be ambiguous ones? They can only arise if a
367 -- top-level decl falls under the monomorphism
368 -- restriction, and no subsequent decl instantiates its
369 -- type. (Usually, ambiguous type variables are resolved
370 -- during the generalisation step.)
371 traceTc (text "Tc8") ;
372 inst_binds <- setEnvs tc_envs (tcSimplifyTop lie) ;
373 -- Setting the global env exposes the instances to tcSimplifyTop
374 -- Setting the local env exposes the local Ids to tcSimplifyTop,
375 -- so that we get better error messages (monomorphism restriction)
377 -- Backsubstitution. This must be done last.
378 -- Even tcSimplifyTop may do some unification.
379 traceTc (text "Tc9") ;
380 let { (tcg_env, _) = tc_envs ;
381 TcGblEnv { tcg_type_env = type_env, tcg_binds = binds,
382 tcg_rules = rules, tcg_fords = fords } = tcg_env } ;
384 (bind_ids, binds', fords', rules') <- zonkTopDecls (binds `unionBags` inst_binds)
387 let { final_type_env = extendTypeEnvWithIds type_env bind_ids } ;
389 -- Compre the hi-boot iface (if any) with the real thing
390 checkHiBootIface final_type_env boot_names ;
392 -- Make the new type env available to stuff slurped from interface files
393 writeMutVar (tcg_type_env_var tcg_env) final_type_env ;
395 return (tcg_env { tcg_type_env = final_type_env,
396 tcg_binds = binds', tcg_rules = rules', tcg_fords = fords' })
399 tc_rn_src_decls :: [Name] -> [LHsDecl RdrName] -> TcM (TcGblEnv, TcLclEnv)
400 -- Loops around dealing with each top level inter-splice group
401 -- in turn, until it's dealt with the entire module
402 tc_rn_src_decls boot_names ds
403 = do { let { (first_group, group_tail) = findSplice ds } ;
404 -- If ds is [] we get ([], Nothing)
406 -- Type check the decls up to, but not including, the first splice
407 tc_envs@(tcg_env,tcl_env) <- tcRnGroup boot_names first_group ;
409 -- Bale out if errors; for example, error recovery when checking
410 -- the RHS of 'main' can mean that 'main' is not in the envt for
411 -- the subsequent checkMain test
416 -- If there is no splice, we're nearly done
418 Nothing -> do { -- Last thing: check for `main'
419 tcg_env <- checkMain ;
420 return (tcg_env, tcl_env)
423 -- If there's a splice, we must carry on
424 Just (SpliceDecl splice_expr, rest_ds) -> do {
426 failWithTc (text "Can't do a top-level splice; need a bootstrapped compiler")
429 -- Rename the splice expression, and get its supporting decls
430 (rn_splice_expr, splice_fvs) <- rnLExpr splice_expr ;
431 failIfErrsM ; -- Don't typecheck if renaming failed
433 -- Execute the splice
434 spliced_decls <- tcSpliceDecls rn_splice_expr ;
436 -- Glue them on the front of the remaining decls and loop
437 setGblEnv (tcg_env `addTcgDUs` usesOnly splice_fvs) $
438 tc_rn_src_decls boot_names (spliced_decls ++ rest_ds)
443 %************************************************************************
445 Compiling hs-boot source files, and
446 comparing the hi-boot interface with the real thing
448 %************************************************************************
451 tcRnHsBootDecls :: [LHsDecl RdrName] -> TcM TcGblEnv
452 tcRnHsBootDecls decls
453 = do { let { (first_group, group_tail) = findSplice decls }
456 Just stuff -> spliceInHsBootErr stuff
459 -- Rename the declarations
460 ; (tcg_env, rn_group) <- rnTopSrcDecls first_group
461 ; setGblEnv tcg_env $ do {
463 -- Todo: check no foreign decls, no rules, no default decls
465 -- Typecheck type/class decls
466 ; traceTc (text "Tc2")
467 ; let tycl_decls = hs_tyclds rn_group
468 ; tcg_env <- checkNoErrs (tcTyAndClassDecls [{- no boot_names -}] tycl_decls)
469 ; setGblEnv tcg_env $ do {
471 -- Typecheck instance decls
472 ; traceTc (text "Tc3")
473 ; (tcg_env, inst_infos, _binds) <- tcInstDecls1 tycl_decls (hs_instds rn_group)
474 ; setGblEnv tcg_env $ do {
476 -- Typecheck value declarations
477 ; traceTc (text "Tc5")
478 ; (tc_val_binds, lcl_env) <- tcHsBootSigs (hs_valds rn_group)
481 -- No simplification or zonking to do
482 ; traceTc (text "Tc7a")
483 ; gbl_env <- getGblEnv
485 ; let { new_ids = [ id | ATcId id _ _ <- varEnvElts (tcl_env lcl_env) ]
486 ; final_type_env = extendTypeEnvWithIds (tcg_type_env gbl_env) new_ids }
488 ; return (gbl_env { tcg_type_env = final_type_env })
491 spliceInHsBootErr (SpliceDecl (L loc _), _)
492 = addErrAt loc (ptext SLIT("Splices are not allowed in hs-boot files"))
495 In both one-shot mode and GHCi mode, hi-boot interfaces are demand-loaded
496 into the External Package Table. Once we've typechecked the body of the
497 module, we want to compare what we've found (gathered in a TypeEnv) with
498 the hi-boot stuff in the EPT. We do so here, using the export list of
499 the hi-boot interface as our checklist.
502 checkHiBootIface :: TypeEnv -> [Name] -> TcM ()
503 -- Compare the hi-boot file for this module (if there is one)
504 -- with the type environment we've just come up with
505 -- In the common case where there is no hi-boot file, the list
506 -- of boot_names is empty.
507 checkHiBootIface env boot_names
508 = mapM_ (check_one env) boot_names
511 check_one local_env name
512 | isWiredInName name -- No checking for wired-in names. In particular, 'error'
513 = return () -- is handled by a rather gross hack (see comments in GHC.Err.hs-boot)
515 = do { (eps,hpt) <- getEpsAndHpt
517 -- Look up the hi-boot one;
518 -- it should jolly well be there (else GHC bug)
519 ; case lookupType hpt (eps_PTE eps) name of {
520 Nothing -> pprPanic "checkHiBootIface" (ppr name) ;
523 -- Look it up in the local type env
524 -- It should be there, but it's a programmer error if not
525 case lookupTypeEnv local_env name of
526 Nothing -> addErrTc (missingBootThing boot_thing)
527 Just real_thing -> check_thing boot_thing real_thing
531 check_thing (ATyCon boot_tc) (ATyCon real_tc)
532 | isSynTyCon boot_tc && isSynTyCon real_tc,
533 defn1 `tcEqType` substTyWith tvs2 (mkTyVarTys tvs1) defn2
536 | tyConKind boot_tc == tyConKind real_tc
539 (tvs1, defn1) = getSynTyConDefn boot_tc
540 (tvs2, defn2) = getSynTyConDefn boot_tc
542 check_thing (AnId boot_id) (AnId real_id)
543 | idType boot_id `tcEqType` idType real_id
546 check_thing (ADataCon dc1) (ADataCon dc2)
547 | idType (dataConWrapId dc1) `tcEqType` idType (dataConWrapId dc2)
550 -- Can't declare a class in a hi-boot file
552 check_thing boot_thing real_thing -- Default case; failure
553 = addErrAt (srcLocSpan (getSrcLoc real_thing))
554 (bootMisMatch real_thing)
557 missingBootThing thing
558 = ppr thing <+> ptext SLIT("is defined in the hs-boot file, but not in the module")
560 = ppr thing <+> ptext SLIT("has conflicting definitions in the module and its hs-boot file")
564 %************************************************************************
566 Type-checking the top level of a module
568 %************************************************************************
570 tcRnGroup takes a bunch of top-level source-code declarations, and
572 * gets supporting declarations from interface files
575 * and augments the TcGblEnv with the results
577 In Template Haskell it may be called repeatedly for each group of
578 declarations. It expects there to be an incoming TcGblEnv in the
579 monad; it augments it and returns the new TcGblEnv.
582 tcRnGroup :: [Name] -> HsGroup RdrName -> TcM (TcGblEnv, TcLclEnv)
583 -- Returns the variables free in the decls, for unused-binding reporting
584 tcRnGroup boot_names decls
585 = do { -- Rename the declarations
586 (tcg_env, rn_decls) <- rnTopSrcDecls decls ;
587 setGblEnv tcg_env $ do {
589 -- Typecheck the declarations
590 tcTopSrcDecls boot_names rn_decls
593 ------------------------------------------------
594 rnTopSrcDecls :: HsGroup RdrName -> TcM (TcGblEnv, HsGroup Name)
596 = do { -- Bring top level binders into scope
597 (rdr_env, imports) <- importsFromLocalDecls group ;
598 updGblEnv (\gbl -> gbl { tcg_rdr_env = rdr_env `plusGlobalRdrEnv` tcg_rdr_env gbl,
599 tcg_imports = imports `plusImportAvails` tcg_imports gbl })
602 traceRn (ptext SLIT("rnTopSrcDecls") <+> ppr rdr_env) ;
603 failIfErrsM ; -- No point in continuing if (say) we have duplicate declarations
605 -- Rename the source decls
606 (tcg_env, rn_decls) <- rnSrcDecls group ;
609 -- Dump trace of renaming part
610 rnDump (ppr rn_decls) ;
612 return (tcg_env, rn_decls)
615 ------------------------------------------------
616 tcTopSrcDecls :: [Name] -> HsGroup Name -> TcM (TcGblEnv, TcLclEnv)
617 tcTopSrcDecls boot_names
618 (HsGroup { hs_tyclds = tycl_decls,
619 hs_instds = inst_decls,
620 hs_fords = foreign_decls,
621 hs_defds = default_decls,
622 hs_ruleds = rule_decls,
623 hs_valds = val_binds })
624 = do { -- Type-check the type and class decls, and all imported decls
625 -- The latter come in via tycl_decls
626 traceTc (text "Tc2") ;
628 tcg_env <- checkNoErrs (tcTyAndClassDecls boot_names tycl_decls) ;
629 -- tcTyAndClassDecls recovers internally, but if anything gave rise to
630 -- an error we'd better stop now, to avoid a cascade
632 -- Make these type and class decls available to stuff slurped from interface files
633 writeMutVar (tcg_type_env_var tcg_env) (tcg_type_env tcg_env) ;
636 setGblEnv tcg_env $ do {
637 -- Source-language instances, including derivings,
638 -- and import the supporting declarations
639 traceTc (text "Tc3") ;
640 (tcg_env, inst_infos, deriv_binds) <- tcInstDecls1 tycl_decls inst_decls ;
641 setGblEnv tcg_env $ do {
643 -- Foreign import declarations next. No zonking necessary
644 -- here; we can tuck them straight into the global environment.
645 traceTc (text "Tc4") ;
646 (fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
647 tcExtendGlobalValEnv fi_ids $ do {
649 -- Default declarations
650 traceTc (text "Tc4a") ;
651 default_tys <- tcDefaults default_decls ;
652 updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
654 -- Value declarations next
655 -- We also typecheck any extra binds that came out
656 -- of the "deriving" process (deriv_binds)
657 traceTc (text "Tc5") ;
658 (tc_val_binds, lcl_env) <- tcTopBinds (val_binds ++ deriv_binds) ;
659 setLclTypeEnv lcl_env $ do {
661 -- Second pass over class and instance declarations,
662 traceTc (text "Tc6") ;
663 (tcl_env, inst_binds) <- tcInstDecls2 tycl_decls inst_infos ;
664 showLIE (text "after instDecls2") ;
667 -- They need to be zonked, so we return them
668 traceTc (text "Tc7") ;
669 (foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
672 rules <- tcRules rule_decls ;
675 traceTc (text "Tc7a") ;
676 tcg_env <- getGblEnv ;
677 let { all_binds = tc_val_binds `unionBags`
678 inst_binds `unionBags`
681 -- Extend the GblEnv with the (as yet un-zonked)
682 -- bindings, rules, foreign decls
683 tcg_env' = tcg_env { tcg_binds = tcg_binds tcg_env `unionBags` all_binds,
684 tcg_rules = tcg_rules tcg_env ++ rules,
685 tcg_fords = tcg_fords tcg_env ++ foe_decls ++ fi_decls } } ;
686 return (tcg_env', lcl_env)
691 %************************************************************************
695 %************************************************************************
699 = do { ghci_mode <- getGhciMode ;
700 tcg_env <- getGblEnv ;
702 mb_main_mod <- readMutVar v_MainModIs ;
703 mb_main_fn <- readMutVar v_MainFunIs ;
704 let { main_mod = case mb_main_mod of {
705 Just mod -> mkModule mod ;
707 main_fn = case mb_main_fn of {
708 Just fn -> mkRdrUnqual (mkVarOcc (mkFastString fn)) ;
709 Nothing -> main_RDR_Unqual } } ;
711 check_main ghci_mode tcg_env main_mod main_fn
715 check_main ghci_mode tcg_env main_mod main_fn
716 -- If we are in module Main, check that 'main' is defined.
717 -- It may be imported from another module!
720 -- Blimey: a whole page of code to do this...
725 = addErrCtxt mainCtxt $
726 do { mb_main <- lookupSrcOcc_maybe main_fn
727 -- Check that 'main' is in scope
728 -- It might be imported from another module!
730 Nothing -> do { complain_no_main
733 { let { rhs = nlHsApp (nlHsVar runMainIOName) (nlHsVar main_name) }
734 -- :Main.main :: IO () = runMainIO main
736 ; (main_expr, ty) <- setSrcSpan (srcLocSpan (getSrcLoc main_name)) $
739 ; let { root_main_id = mkExportedLocalId rootMainName ty ;
740 main_bind = noLoc (VarBind root_main_id main_expr) }
742 ; return (tcg_env { tcg_binds = tcg_binds tcg_env
744 tcg_dus = tcg_dus tcg_env
745 `plusDU` usesOnly (unitFV main_name)
746 -- Record the use of 'main', so that we don't
747 -- complain about it being defined but not used
751 mod = tcg_mod tcg_env
753 complain_no_main | ghci_mode == Interactive = return ()
754 | otherwise = failWithTc noMainMsg
755 -- In interactive mode, don't worry about the absence of 'main'
756 -- In other modes, fail altogether, so that we don't go on
757 -- and complain a second time when processing the export list.
759 mainCtxt = ptext SLIT("When checking the type of the main function") <+> quotes (ppr main_fn)
760 noMainMsg = ptext SLIT("The main function") <+> quotes (ppr main_fn)
761 <+> ptext SLIT("is not defined in module") <+> quotes (ppr main_mod)
765 %*********************************************************
769 %*********************************************************
773 setInteractiveContext :: HscEnv -> InteractiveContext -> TcRn a -> TcRn a
774 setInteractiveContext hsc_env icxt thing_inside
776 -- Initialise the tcg_inst_env with instances
777 -- from all home modules. This mimics the more selective
778 -- call to hptInstances in tcRnModule
779 dfuns = hptInstances hsc_env (\mod -> True)
781 updGblEnv (\env -> env {
782 tcg_rdr_env = ic_rn_gbl_env icxt,
783 tcg_type_env = ic_type_env icxt,
784 tcg_inst_env = extendInstEnvList (tcg_inst_env env) dfuns }) $
786 updLclEnv (\env -> env { tcl_rdr = ic_rn_local_env icxt }) $
788 do { traceTc (text "setIC" <+> ppr (ic_type_env icxt))
795 -> InteractiveContext
797 -> IO (Maybe (InteractiveContext, [Name], LHsExpr Id))
798 -- The returned [Name] is the same as the input except for
799 -- ExprStmt, in which case the returned [Name] is [itName]
801 -- The returned TypecheckedHsExpr is of type IO [ () ],
802 -- a list of the bound values, coerced to ().
804 tcRnStmt hsc_env ictxt rdr_stmt
805 = initTcPrintErrors hsc_env iNTERACTIVE $
806 setInteractiveContext hsc_env ictxt $ do {
808 -- Rename; use CmdLineMode because tcRnStmt is only used interactively
809 ([rn_stmt], fvs) <- rnStmts DoExpr [rdr_stmt] ;
810 traceRn (text "tcRnStmt" <+> vcat [ppr rdr_stmt, ppr rn_stmt, ppr fvs]) ;
813 -- The real work is done here
814 (bound_ids, tc_expr) <- tcUserStmt rn_stmt ;
816 traceTc (text "tcs 1") ;
817 let { -- (a) Make all the bound ids "global" ids, now that
818 -- they're notionally top-level bindings. This is
819 -- important: otherwise when we come to compile an expression
820 -- using these ids later, the byte code generator will consider
821 -- the occurrences to be free rather than global.
823 -- (b) Tidy their types; this is important, because :info may
824 -- ask to look at them, and :info expects the things it looks
825 -- up to have tidy types
826 global_ids = map globaliseAndTidy bound_ids ;
828 -- Update the interactive context
829 rn_env = ic_rn_local_env ictxt ;
830 type_env = ic_type_env ictxt ;
832 bound_names = map idName global_ids ;
833 new_rn_env = extendLocalRdrEnv rn_env bound_names ;
835 -- Remove any shadowed bindings from the type_env;
836 -- they are inaccessible but might, I suppose, cause
837 -- a space leak if we leave them there
838 shadowed = [ n | name <- bound_names,
839 let rdr_name = mkRdrUnqual (nameOccName name),
840 Just n <- [lookupLocalRdrEnv rn_env rdr_name] ] ;
842 filtered_type_env = delListFromNameEnv type_env shadowed ;
843 new_type_env = extendTypeEnvWithIds filtered_type_env global_ids ;
845 new_ic = ictxt { ic_rn_local_env = new_rn_env,
846 ic_type_env = new_type_env }
849 dumpOptTcRn Opt_D_dump_tc
850 (vcat [text "Bound Ids" <+> pprWithCommas ppr global_ids,
851 text "Typechecked expr" <+> ppr tc_expr]) ;
853 returnM (new_ic, bound_names, tc_expr)
856 globaliseAndTidy :: Id -> Id
858 -- Give the Id a Global Name, and tidy its type
859 = setIdType (globaliseId VanillaGlobal id) tidy_type
861 tidy_type = tidyTopType (idType id)
864 Here is the grand plan, implemented in tcUserStmt
866 What you type The IO [HValue] that hscStmt returns
867 ------------- ------------------------------------
868 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
871 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
874 expr (of IO type) ==> expr >>= \ it -> return [coerce HVal it]
875 [NB: result not printed] bindings: [it]
877 expr (of non-IO type, ==> let it = expr in print it >> return [coerce HVal it]
878 result showable) bindings: [it]
880 expr (of non-IO type,
881 result not showable) ==> error
885 ---------------------------
886 tcUserStmt :: LStmt Name -> TcM ([Id], LHsExpr Id)
887 tcUserStmt (L _ (ExprStmt expr _))
888 = newUnique `thenM` \ uniq ->
890 fresh_it = itName uniq
891 the_bind = noLoc $ FunBind (noLoc fresh_it) False
892 (mkMatchGroup [mkSimpleMatch [] expr])
894 tryTcLIE_ (do { -- Try this if the other fails
895 traceTc (text "tcs 1b") ;
897 nlLetStmt [HsBindGroup (unitBag the_bind) [] NonRecursive],
898 nlExprStmt (nlHsApp (nlHsVar printName)
901 (do { -- Try this first
902 traceTc (text "tcs 1a") ;
903 tc_stmts [nlBindStmt (nlVarPat fresh_it) expr] })
905 tcUserStmt stmt = tc_stmts [stmt]
907 ---------------------------
909 = do { ioTyCon <- tcLookupTyCon ioTyConName ;
911 ret_ty = mkListTy unitTy ;
912 io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
914 names = map unLoc (collectStmtsBinders stmts) ;
916 stmt_ctxt = SC { sc_what = DoExpr,
918 sc_body = check_body,
921 infer_rhs rhs = do { (rhs', rhs_ty) <- tcInferRho rhs
922 ; [pat_ty] <- unifyTyConApp ioTyCon rhs_ty
923 ; return (rhs', pat_ty) } ;
924 check_body body = tcCheckRho body io_ret_ty ;
926 -- mk_return builds the expression
927 -- returnIO @ [()] [coerce () x, .., coerce () z]
929 -- Despite the inconvenience of building the type applications etc,
930 -- this *has* to be done in type-annotated post-typecheck form
931 -- because we are going to return a list of *polymorphic* values
932 -- coerced to type (). If we built a *source* stmt
933 -- return [coerce x, ..., coerce z]
934 -- then the type checker would instantiate x..z, and we wouldn't
935 -- get their *polymorphic* values. (And we'd get ambiguity errs
936 -- if they were overloaded, since they aren't applied to anything.)
937 mk_return ret_id ids = nlHsApp (noLoc $ TyApp (nlHsVar ret_id) [ret_ty])
938 (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
939 mk_item id = nlHsApp (noLoc $ TyApp (nlHsVar unsafeCoerceId) [idType id, unitTy])
942 io_ty = mkTyConApp ioTyCon []
945 -- OK, we're ready to typecheck the stmts
946 traceTc (text "tcs 2") ;
947 ((ids, tc_expr), lie) <- getLIE $ do {
948 (ids, tc_stmts) <- tcStmtsAndThen combine stmt_ctxt stmts $
950 -- Look up the names right in the middle,
951 -- where they will all be in scope
952 ids <- mappM tcLookupId names ;
953 ret_id <- tcLookupId returnIOName ; -- return @ IO
954 return (ids, [nlResultStmt (mk_return ret_id ids)]) } ;
956 io_ids <- mappM (tcStdSyntaxName DoOrigin io_ty) monadNames ;
957 return (ids, noLoc (HsDo DoExpr tc_stmts io_ids io_ret_ty))
960 -- Simplify the context right here, so that we fail
961 -- if there aren't enough instances. Notably, when we see
963 -- we use recoverTc_ to try it <- e
964 -- and then let it = e
965 -- It's the simplify step that rejects the first.
966 traceTc (text "tcs 3") ;
967 const_binds <- tcSimplifyInteractive lie ;
969 -- Build result expression and zonk it
970 let { expr = mkHsLet const_binds tc_expr } ;
971 zonked_expr <- zonkTopLExpr expr ;
972 zonked_ids <- zonkTopBndrs ids ;
974 -- None of the Ids should be of unboxed type, because we
975 -- cast them all to HValues in the end!
976 mappM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
978 return (zonked_ids, zonked_expr)
981 combine stmt (ids, stmts) = (ids, stmt:stmts)
982 bad_unboxed id = addErr (sep [ptext SLIT("GHCi can't bind a variable of unlifted type:"),
983 nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
987 tcRnExpr just finds the type of an expression
991 -> InteractiveContext
994 tcRnExpr hsc_env ictxt rdr_expr
995 = initTcPrintErrors hsc_env iNTERACTIVE $
996 setInteractiveContext hsc_env ictxt $ do {
998 (rn_expr, fvs) <- rnLExpr rdr_expr ;
1001 -- Now typecheck the expression;
1002 -- it might have a rank-2 type (e.g. :t runST)
1003 ((tc_expr, res_ty), lie) <- getLIE (tcInferRho rn_expr) ;
1004 ((qtvs, _, dict_ids), lie_top) <- getLIE (tcSimplifyInfer smpl_doc (tyVarsOfType res_ty) lie) ;
1005 tcSimplifyInteractive lie_top ;
1006 qtvs' <- mappM zonkQuantifiedTyVar qtvs ;
1008 let { all_expr_ty = mkForAllTys qtvs' $
1009 mkFunTys (map idType dict_ids) $
1011 zonkTcType all_expr_ty
1014 smpl_doc = ptext SLIT("main expression")
1017 tcRnType just finds the kind of a type
1021 -> InteractiveContext
1024 tcRnType hsc_env ictxt rdr_type
1025 = initTcPrintErrors hsc_env iNTERACTIVE $
1026 setInteractiveContext hsc_env ictxt $ do {
1028 rn_type <- rnLHsType doc rdr_type ;
1031 -- Now kind-check the type
1032 (ty', kind) <- kcHsType rn_type ;
1036 doc = ptext SLIT("In GHCi input")
1042 %************************************************************************
1044 More GHCi stuff, to do with browsing and getting info
1046 %************************************************************************
1050 mkExportEnv :: HscEnv -> [Module] -- Expose these modules' exports only
1052 mkExportEnv hsc_env exports
1053 = do { mb_envs <- initTcPrintErrors hsc_env iNTERACTIVE $
1054 mappM getModuleExports exports
1056 Just envs -> return (foldr plusGlobalRdrEnv emptyGlobalRdrEnv envs)
1057 Nothing -> return emptyGlobalRdrEnv
1058 -- Some error; initTc will have printed it
1061 getModuleExports :: Module -> TcM GlobalRdrEnv
1062 getModuleExports mod
1063 = do { iface <- load_iface mod
1064 ; loadOrphanModules (dep_orphs (mi_deps iface))
1065 -- Load any orphan-module interfaces,
1066 -- so their instances are visible
1067 ; names <- exportsToAvails (mi_exports iface)
1068 ; let { gres = [ GRE { gre_name = name, gre_prov = vanillaProv mod }
1069 | name <- nameSetToList names ] }
1070 ; returnM (mkGlobalRdrEnv gres) }
1072 vanillaProv :: Module -> Provenance
1073 -- We're building a GlobalRdrEnv as if the user imported
1074 -- all the specified modules into the global interactive module
1075 vanillaProv mod = Imported [ImportSpec mod mod False
1076 (srcLocSpan interactiveSrcLoc)] False
1082 -> InteractiveContext
1083 -> Module -- Module to inspect
1084 -> Bool -- Grab just the exports, or the whole toplev
1085 -> IO (Maybe [IfaceDecl])
1087 getModuleContents hsc_env ictxt mod exports_only
1088 = initTcPrintErrors hsc_env iNTERACTIVE (get_mod_contents exports_only)
1090 get_mod_contents exports_only
1091 | not exports_only -- We want the whole top-level type env
1092 -- so it had better be a home module
1093 = do { hpt <- getHpt
1094 ; case lookupModuleEnv hpt mod of
1095 Just mod_info -> return (map (toIfaceDecl ext_nm) $
1098 md_types (hm_details mod_info))
1099 Nothing -> ghcError (ProgramError (showSDoc (noRdrEnvErr mod)))
1100 -- This is a system error; the module should be in the HPT
1103 | otherwise -- Want the exports only
1104 = do { iface <- load_iface mod
1105 ; mappM get_decl [ (mod,avail) | (mod, avails) <- mi_exports iface
1109 get_decl (mod, avail)
1110 = do { main_name <- lookupOrig mod (availName avail)
1111 ; thing <- tcLookupGlobal main_name
1112 ; return (filter_decl (availNames avail) (toIfaceDecl ext_nm thing)) }
1114 ext_nm = interactiveExtNameFun (icPrintUnqual ictxt)
1116 ---------------------
1117 filter_decl occs decl@(IfaceClass {ifSigs = sigs})
1118 = decl { ifSigs = filter (keep_sig occs) sigs }
1119 filter_decl occs decl@(IfaceData {ifCons = IfDataTyCon th cons})
1120 = decl { ifCons = IfDataTyCon th (filter (keep_con occs) cons) }
1121 filter_decl occs decl@(IfaceData {ifCons = IfNewTyCon con})
1122 | keep_con occs con = decl
1123 | otherwise = decl {ifCons = IfAbstractTyCon} -- Hmm?
1124 filter_decl occs decl
1127 keep_sig occs (IfaceClassOp occ _ _) = occ `elem` occs
1128 keep_con occs con = ifConOcc con `elem` occs
1130 wantToSee (AnId id) = not (isImplicitId id)
1131 wantToSee (ADataCon _) = False -- They'll come via their TyCon
1134 ---------------------
1135 load_iface mod = loadSrcInterface doc mod False {- Not boot iface -}
1137 doc = ptext SLIT("context for compiling statements")
1139 ---------------------
1140 noRdrEnvErr mod = ptext SLIT("No top-level environment available for module")
1141 <+> quotes (ppr mod)
1145 tcRnGetInfo :: HscEnv
1146 -> InteractiveContext
1148 -> IO (Maybe [(IfaceDecl,
1150 [(IfaceInst, SrcLoc)])])
1151 -- Used to implemnent :info in GHCi
1153 -- Look up a RdrName and return all the TyThings it might be
1154 -- A capitalised RdrName is given to us in the DataName namespace,
1155 -- but we want to treat it as *both* a data constructor
1156 -- *and* as a type or class constructor;
1157 -- hence the call to dataTcOccs, and we return up to two results
1158 tcRnGetInfo hsc_env ictxt rdr_name
1159 = initTcPrintErrors hsc_env iNTERACTIVE $
1160 setInteractiveContext hsc_env ictxt $ do {
1162 -- If the identifier is a constructor (begins with an
1163 -- upper-case letter), then we need to consider both
1164 -- constructor and type class identifiers.
1165 let { rdr_names = dataTcOccs rdr_name } ;
1167 -- results :: [(Messages, Maybe Name)]
1168 results <- mapM (tryTc . lookupOccRn) rdr_names ;
1170 traceRn (text "xx" <+> vcat [ppr rdr_names, ppr (map snd results)]);
1171 -- The successful lookups will be (Just name)
1172 let { (warns_s, good_names) = unzip [ (msgs, name)
1173 | (msgs, Just name) <- results] ;
1174 errs_s = [msgs | (msgs, Nothing) <- results] } ;
1176 -- Fail if nothing good happened, else add warnings
1177 if null good_names then
1178 -- No lookup succeeded, so
1179 -- pick the first error message and report it
1180 -- ToDo: If one of the errors is "could be Foo.X or Baz.X",
1181 -- while the other is "X is not in scope",
1182 -- we definitely want the former; but we might pick the latter
1183 do { addMessages (head errs_s) ; failM }
1184 else -- Add deprecation warnings
1185 mapM_ addMessages warns_s ;
1187 -- And lookup up the entities, avoiding duplicates, which arise
1188 -- because constructors and record selectors are represented by
1189 -- their parent declaration
1190 let { do_one name = do { thing <- tcLookupGlobal name
1191 ; fixity <- lookupFixityRn name
1192 ; insts <- lookupInsts ext_nm thing
1193 ; return (toIfaceDecl ext_nm thing, fixity,
1194 getSrcLoc thing, insts) } } ;
1195 -- For the SrcLoc, the 'thing' has better info than
1196 -- the 'name' because getting the former forced the
1197 -- declaration to be loaded into the cache
1199 results <- mapM do_one good_names ;
1200 return (fst (removeDups cmp results))
1203 cmp (d1,_,_,_) (d2,_,_,_) = ifName d1 `compare` ifName d2
1204 ext_nm = interactiveExtNameFun (icPrintUnqual ictxt)
1207 lookupInsts :: (Name -> IfaceExtName) -> TyThing -> TcM [(IfaceInst, SrcLoc)]
1208 -- Filter the instances by the ones whose tycons (or clases resp)
1209 -- are in scope unqualified. Otherwise we list a whole lot too many!
1210 lookupInsts ext_nm (AClass cls)
1211 = do { loadImportedInsts cls [] -- [] means load all instances for cls
1212 ; inst_envs <- tcGetInstEnvs
1213 ; return [ (inst, getSrcLoc dfun)
1214 | (_,_,dfun) <- classInstances inst_envs cls
1215 , let inst = dfunToIfaceInst ext_nm dfun
1216 (_, tycons) = ifaceInstGates (ifInstHead inst)
1217 , all print_tycon_unqual tycons ] }
1219 print_tycon_unqual (IfaceTc nm) = isLocalIfaceExtName nm
1220 print_tycon_unqual other = True -- Int etc
1223 lookupInsts ext_nm (ATyCon tc)
1224 = do { eps <- getEps -- Load all instances for all classes that are
1225 -- in the type environment (which are all the ones
1226 -- we've seen in any interface file so far)
1227 ; mapM_ (\c -> loadImportedInsts c [])
1228 (typeEnvClasses (eps_PTE eps))
1229 ; (pkg_ie, home_ie) <- tcGetInstEnvs -- Search all
1230 ; return [ (inst, getSrcLoc dfun)
1231 | (_, _, dfun) <- instEnvElts home_ie ++ instEnvElts pkg_ie
1233 , let inst = dfunToIfaceInst ext_nm dfun
1234 (cls, _) = ifaceInstGates (ifInstHead inst)
1235 , isLocalIfaceExtName cls ] }
1237 relevant df = tc_name `elemNameSet` tyClsNamesOfDFunHead (idType df)
1238 tc_name = tyConName tc
1240 lookupInsts ext_nm other = return []
1243 toIfaceDecl :: (Name -> IfaceExtName) -> TyThing -> IfaceDecl
1244 toIfaceDecl ext_nm thing
1245 = tyThingToIfaceDecl True -- Discard IdInfo
1246 emptyNameSet -- Show data cons
1247 ext_nm (munge thing)
1249 -- munge transforms a thing to its "parent" thing
1250 munge (ADataCon dc) = ATyCon (dataConTyCon dc)
1251 munge (AnId id) = case globalIdDetails id of
1252 RecordSelId tc lbl -> ATyCon tc
1253 ClassOpId cls -> AClass cls
1255 munge other_thing = other_thing
1259 %************************************************************************
1263 %************************************************************************
1266 rnDump :: SDoc -> TcRn ()
1267 -- Dump, with a banner, if -ddump-rn
1268 rnDump doc = do { dumpOptTcRn Opt_D_dump_rn (mkDumpDoc "Renamer" doc) }
1270 tcDump :: TcGblEnv -> TcRn ()
1272 = do { dflags <- getDOpts ;
1274 -- Dump short output if -ddump-types or -ddump-tc
1275 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1276 (dumpTcRn short_dump) ;
1278 -- Dump bindings if -ddump-tc
1279 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump)
1282 short_dump = pprTcGblEnv env
1283 full_dump = pprLHsBinds (tcg_binds env)
1284 -- NB: foreign x-d's have undefined's in their types;
1285 -- hence can't show the tc_fords
1288 = do { dflags <- getDOpts ;
1289 ifM (dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags)
1290 (dumpTcRn (pprModGuts mod_guts)) ;
1292 -- Dump bindings if -ddump-tc
1293 dumpOptTcRn Opt_D_dump_tc (mkDumpDoc "Typechecker" full_dump) }
1295 full_dump = pprCoreBindings (mg_binds mod_guts)
1297 -- It's unpleasant having both pprModGuts and pprModDetails here
1298 pprTcGblEnv :: TcGblEnv -> SDoc
1299 pprTcGblEnv (TcGblEnv { tcg_type_env = type_env,
1300 tcg_insts = dfun_ids,
1302 tcg_imports = imports })
1303 = vcat [ ppr_types dfun_ids type_env
1304 , ppr_insts dfun_ids
1305 , vcat (map ppr rules)
1306 , ppr_gen_tycons (typeEnvTyCons type_env)
1307 , ptext SLIT("Dependent modules:") <+> ppr (moduleEnvElts (imp_dep_mods imports))
1308 , ptext SLIT("Dependent packages:") <+> ppr (imp_dep_pkgs imports)]
1310 pprModGuts :: ModGuts -> SDoc
1311 pprModGuts (ModGuts { mg_types = type_env,
1313 = vcat [ ppr_types [] type_env,
1317 ppr_types :: [Var] -> TypeEnv -> SDoc
1318 ppr_types dfun_ids type_env
1319 = text "TYPE SIGNATURES" $$ nest 4 (ppr_sigs ids)
1321 ids = [id | id <- typeEnvIds type_env, want_sig id]
1322 want_sig id | opt_PprStyle_Debug = True
1323 | otherwise = isLocalId id &&
1324 isExternalName (idName id) &&
1325 not (id `elem` dfun_ids)
1326 -- isLocalId ignores data constructors, records selectors etc.
1327 -- The isExternalName ignores local dictionary and method bindings
1328 -- that the type checker has invented. Top-level user-defined things
1329 -- have External names.
1331 ppr_insts :: [Var] -> SDoc
1332 ppr_insts [] = empty
1333 ppr_insts dfun_ids = text "INSTANCES" $$ nest 4 (ppr_sigs dfun_ids)
1335 ppr_sigs :: [Var] -> SDoc
1337 -- Print type signatures; sort by OccName
1338 = vcat (map ppr_sig (sortLe le_sig ids))
1340 le_sig id1 id2 = getOccName id1 <= getOccName id2
1341 ppr_sig id = ppr id <+> dcolon <+> ppr (tidyTopType (idType id))
1343 ppr_rules :: [IdCoreRule] -> SDoc
1344 ppr_rules [] = empty
1345 ppr_rules rs = vcat [ptext SLIT("{-# RULES"),
1346 nest 4 (pprIdRules rs),
1349 ppr_gen_tycons [] = empty
1350 ppr_gen_tycons tcs = vcat [ptext SLIT("Tycons with generics:"),
1351 nest 2 (fsep (map ppr (filter tyConHasGenerics tcs)))]