X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcModule.lhs;h=e21730a3beaee91ef9ccaafa57f492e87da83265;hb=29e5b129c2e95d8890048f5dd27711c351db8e7e;hp=c1681411e9f7035b8e982e130e6383f497bda343;hpb=5a3d687acb70ecc03991c3a4f47f940eb2866a63;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcModule.lhs b/ghc/compiler/typecheck/TcModule.lhs index c168141..e21730a 100644 --- a/ghc/compiler/typecheck/TcModule.lhs +++ b/ghc/compiler/typecheck/TcModule.lhs @@ -1,328 +1,314 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[TcModule]{Typechecking a whole module} \begin{code} -#include "HsVersions.h" - module TcModule ( typecheckModule, - SYN_IE(TcResults), - SYN_IE(TcResultBinds), - SYN_IE(TcSpecialiseRequests), - SYN_IE(TcDDumpDeriv) + TcResults(..) ) where -IMP_Ubiq(){-uitous-} +#include "HsVersions.h" -import HsSyn ( HsDecl(..), HsModule(..), HsBinds(..), HsExpr, MonoBinds, - TyDecl, SpecDataSig, ClassDecl, InstDecl, IfaceSig, - SpecInstSig, DefaultDecl, Sig, Fake, InPat, - SYN_IE(RecFlag), nonRecursive, - FixityDecl, IE, ImportDecl +import CmdLineOpts ( opt_D_dump_tc, opt_D_dump_types, opt_PprStyle_Debug ) +import HsSyn ( HsModule(..), HsBinds(..), MonoBinds(..), HsDecl(..) ) +import HsTypes ( toHsType ) +import RnHsSyn ( RenamedHsModule ) +import TcHsSyn ( TcMonoBinds, TypecheckedMonoBinds, + TypecheckedForeignDecl, TypecheckedRuleDecl, + zonkTopBinds, zonkForeignExports, zonkRules ) -import RnHsSyn ( SYN_IE(RenamedHsModule), RenamedFixityDecl(..) ) -import TcHsSyn ( SYN_IE(TypecheckedHsBinds), SYN_IE(TypecheckedHsExpr), - SYN_IE(TypecheckedDictBinds), - TcIdOcc(..), zonkBinds ) import TcMonad -import Inst ( Inst, plusLIE ) -import TcBinds ( tcBindsAndThen ) -import TcClassDcl ( tcClassDecls2 ) +import Inst ( Inst, emptyLIE, plusLIE ) +import TcBinds ( tcTopBindsAndThen ) +import TcClassDcl ( tcClassDecls2, mkImplicitClassBinds ) import TcDefaults ( tcDefaults ) -import TcEnv ( tcExtendGlobalValEnv, getEnv_LocalIds, - getEnv_TyCons, getEnv_Classes, tcLookupLocalValue, - tcLookupLocalValueByKey, tcLookupTyCon, - tcLookupGlobalValueByKeyMaybe ) -import SpecEnv ( SpecEnv ) +import TcEnv ( tcExtendGlobalValEnv, tcExtendTypeEnv, + getEnvTyCons, getEnvClasses, tcLookupValueByKeyMaybe, + explicitLookupValueByKey, tcSetValueEnv, + initEnv, + ValueEnv, TcTyThing(..) + ) import TcExpr ( tcId ) +import TcRules ( tcRules ) +import TcForeign ( tcForeignImports, tcForeignExports ) import TcIfaceSig ( tcInterfaceSigs ) import TcInstDcls ( tcInstDecls1, tcInstDecls2 ) -import TcInstUtil ( buildInstanceEnvs, InstInfo ) +import TcInstUtil ( buildInstanceEnvs, classDataCon, InstInfo ) import TcSimplify ( tcSimplifyTop ) -import TcTyClsDecls ( tcTyAndClassDecls1 ) -import TcTyDecls ( mkDataBinds ) -import TcType ( SYN_IE(TcType), tcInstType ) -import TcKind ( TcKind ) - -import RnMonad ( RnNameSupply(..) ) -import Bag ( listToBag ) -import ErrUtils ( SYN_IE(Warning), SYN_IE(Error) ) -import Id ( idType, GenId, SYN_IE(IdEnv), nullIdEnv ) -import Maybes ( catMaybes, MaybeErr ) -import Name ( Name, isLocallyDefined, pprModule ) -import Pretty -import TyCon ( TyCon, isSynTyCon ) -import Class ( GenClass, SYN_IE(Class), classGlobalIds ) -import Type ( applyTyCon, mkSynTy, SYN_IE(Type) ) -import PprType ( GenType, GenTyVar ) +import TcTyClsDecls ( tcTyAndClassDecls ) +import TcTyDecls ( mkImplicitDataBinds ) +import TcType ( TcType, typeToTcType, + TcKind, kindToTcKind, + newTyVarTy + ) + +import RnMonad ( RnNameSupply, FixityEnv ) +import Bag ( isEmptyBag ) +import ErrUtils ( Message, printErrorsAndWarnings, dumpIfSet ) +import Id ( Id, idType, idName ) +import Module ( pprModuleName ) +import OccName ( isSysOcc ) +import Name ( Name, nameUnique, nameOccName, isLocallyDefined, + toRdrName, nameEnvElts, NamedThing(..) + ) +import TyCon ( TyCon, tyConKind ) +import Class ( Class, classSelIds, classTyCon ) +import Type ( mkTyConApp, mkForAllTy, + boxedTypeKind, getTyVar, Type ) import TysWiredIn ( unitTy ) -import PrelMods ( gHC_MAIN, mAIN ) -import PrelInfo ( main_NAME, mainPrimIO_NAME, ioTyCon_NAME, primIoTyCon_NAME ) -import TyVar ( GenTyVar, SYN_IE(TyVarEnv), nullTyVarEnv ) -import Unify ( unifyTauTy ) -import UniqFM ( lookupUFM_Directly, lookupWithDefaultUFM_Directly, - filterUFM, eltsUFM ) -import Unique ( Unique ) +import PrelInfo ( mAIN_Name ) +import TcUnify ( unifyTauTy ) +import Unique ( Unique, mainKey ) import UniqSupply ( UniqSupply ) +import Maybes ( maybeToBool ) import Util import Bag ( Bag, isEmptyBag ) +import Outputable -import FiniteMap ( emptyFM, FiniteMap ) - -import Outputable ( Outputable(..), PprStyle ) - -tycon_specs = emptyFM +import IOExts \end{code} Outside-world interface: \begin{code} + -- Convenient type synonyms first: -type TcResults - = (TcResultBinds, - [TyCon], [Class], - Bag InstInfo, -- Instance declaration information - TcSpecialiseRequests, - TcDDumpDeriv) - -type TcResultBinds - = (TypecheckedHsBinds, -- record selector binds - TypecheckedHsBinds, -- binds from class decls; does NOT - -- include default-methods bindings - TypecheckedHsBinds, -- binds from instance decls; INCLUDES - -- class default-methods binds - TypecheckedHsBinds, -- binds from value decls - - TypecheckedHsBinds) -- constant instance binds - -type TcSpecialiseRequests - = FiniteMap TyCon [(Bool, [Maybe Type])] - -- source tycon specialisation requests - -type TcDDumpDeriv - = PprStyle -> Doc +data TcResults + = TcResults { + tc_binds :: TypecheckedMonoBinds, + tc_tycons :: [TyCon], + tc_classes :: [Class], + tc_insts :: Bag InstInfo, -- Instance declaration information + tc_fords :: [TypecheckedForeignDecl], -- Foreign import & exports. + tc_rules :: [TypecheckedRuleDecl], -- Transformation rules + tc_env :: ValueEnv + } --------------- typecheckModule :: UniqSupply -> RnNameSupply + -> FixityEnv -> RenamedHsModule - -> MaybeErr - (TcResults, -- if all goes well... - Bag Warning) -- (we can still get warnings) - (Bag Error, -- if we had errors... - Bag Warning) - -typecheckModule us rn_name_supply mod - = initTc us (tcModule rn_name_supply mod) + -> IO (Maybe TcResults) + +typecheckModule us rn_name_supply fixity_env mod + = initTc us initEnv (tcModule rn_name_supply fixity_env mod) >>= \ (maybe_result, warns, errs) -> + + printErrorsAndWarnings errs warns >> + + (case maybe_result of + Nothing -> return () + Just results -> dumpIfSet opt_D_dump_types "Type signatures" (dump_sigs results) >> + dumpIfSet opt_D_dump_tc "Typechecked" (dump_tc results) + ) >> + + return (if isEmptyBag errs then + maybe_result + else + Nothing) + +dump_tc results + = ppr (tc_binds results) $$ pp_rules (tc_rules results) + +dump_sigs results -- Print type signatures + = -- Convert to HsType so that we get source-language style printing + -- And sort by RdrName + vcat $ map ppr_sig $ sortLt lt_sig $ + [(toRdrName id, toHsType (idType id)) | id <- nameEnvElts (tc_env results), + want_sig id + ] + where + lt_sig (n1,_) (n2,_) = n1 < n2 + ppr_sig (n,t) = ppr n <+> dcolon <+> ppr t + + want_sig id | opt_PprStyle_Debug = True + | otherwise = isLocallyDefined n && not (isSysOcc (nameOccName n)) + where + n = idName id + +pp_rules [] = empty +pp_rules rs = vcat [ptext SLIT("{-# RULES"), + nest 4 (vcat (map ppr rs)), + ptext SLIT("#-}")] \end{code} The internal monster: \begin{code} tcModule :: RnNameSupply -- for renaming derivings + -> FixityEnv -- needed for Show/Read derivings. -> RenamedHsModule -- input -> TcM s TcResults -- output -tcModule rn_name_supply - (HsModule mod_name verion exports imports fixities decls src_loc) +tcModule rn_name_supply fixities + (HsModule mod_name _ _ _ decls _ src_loc) = tcAddSrcLoc src_loc $ -- record where we're starting - -- Tie the knot for inteface-file value declaration signatures - -- This info is only used inside the knot for type-checking the - -- pragmas, which is done lazily [ie failure just drops the pragma + fixTc (\ ~(unf_env ,_) -> + -- unf_env is used for type-checking interface pragmas + -- which is done lazily [ie failure just drops the pragma -- without having any global-failure effect]. - - -- trace "tc1" $ - - fixTc (\ ~(_, _, _, _, _, _, sig_ids) -> - - -- trace "tc2" $ - tcExtendGlobalValEnv sig_ids ( - - -- The knot for instance information. This isn't used at all - -- till we type-check value declarations - fixTc ( \ ~(rec_inst_mapper, _, _, _, _) -> - - -- Type-check the type and class decls - -- trace "tcTyAndClassDecls:" $ - tcTyAndClassDecls1 rec_inst_mapper decls `thenTc` \ env -> - - -- trace "tc3" $ - -- Typecheck the instance decls, includes deriving - tcSetEnv env ( - -- trace "tcInstDecls:" $ - tcInstDecls1 decls mod_name rn_name_supply - ) `thenTc` \ (inst_info, deriv_binds, ddump_deriv) -> - - -- trace "tc4" $ - buildInstanceEnvs inst_info `thenTc` \ inst_mapper -> - - returnTc (inst_mapper, env, inst_info, deriv_binds, ddump_deriv) - - ) `thenTc` \ (_, env, inst_info, deriv_binds, ddump_deriv) -> - - -- trace "tc5" $ - tcSetEnv env ( - - -- Default declarations - tcDefaults decls `thenTc` \ defaulting_tys -> - tcSetDefaultTys defaulting_tys ( -- for the iface sigs... - - -- Create any necessary record selector Ids and their bindings - -- "Necessary" includes data and newtype declarations - let - tycons = getEnv_TyCons env - classes = getEnv_Classes env - in - mkDataBinds tycons `thenTc` \ (data_ids, data_binds) -> - - -- Extend the global value environment with - -- a) constructors - -- b) record selectors - -- c) class op selectors - -- d) default-method ids - tcExtendGlobalValEnv data_ids $ - tcExtendGlobalValEnv (concat (map classGlobalIds classes)) $ - - -- Interface type signatures - -- We tie a knot so that the Ids read out of interfaces are in scope - -- when we read their pragmas. - -- What we rely on is that pragmas are typechecked lazily; if - -- any type errors are found (ie there's an inconsistency) - -- we silently discard the pragma - tcInterfaceSigs decls `thenTc` \ sig_ids -> - tcGetEnv `thenNF_Tc` \ env -> - -- trace "tc6" $ - - returnTc (env, inst_info, data_binds, deriv_binds, ddump_deriv, defaulting_tys, sig_ids) - - )))) `thenTc` \ (env, inst_info, data_binds, deriv_binds, ddump_deriv, defaulting_tys, _) -> - - -- trace "tc7" $ - tcSetEnv env ( -- to the end... - tcSetDefaultTys defaulting_tys ( -- ditto + -- + -- unf_env is also used to get the pragam info + -- for imported dfuns and default methods + + -- The knot for instance information. This isn't used at all + -- till we type-check value declarations + fixTc ( \ ~(rec_inst_mapper, _, _, _) -> + + -- Type-check the type and class decls + tcTyAndClassDecls unf_env rec_inst_mapper decls `thenTc` \ env -> + + -- Typecheck the instance decls, includes deriving + tcSetEnv env ( + tcInstDecls1 unf_env decls mod_name fixities rn_name_supply + ) `thenTc` \ (inst_info, deriv_binds) -> + + buildInstanceEnvs inst_info `thenNF_Tc` \ inst_mapper -> + + returnTc (inst_mapper, env, inst_info, deriv_binds) + + -- End of inner fix loop + ) `thenTc` \ (_, env, inst_info, deriv_binds) -> + + tcSetEnv env ( + let + tycons = getEnvTyCons env + classes = getEnvClasses env + local_tycons = filter isLocallyDefined tycons + local_classes = filter isLocallyDefined classes + in + + -- Default declarations + tcDefaults decls `thenTc` \ defaulting_tys -> + tcSetDefaultTys defaulting_tys $ + + -- Extend the TyCon envt with the tycons corresponding to + -- the classes. + -- They are mentioned in types in interface files. + tcExtendTypeEnv [ (getName tycon, (kindToTcKind (tyConKind tycon), ADataTyCon tycon)) + | clas <- classes, + let tycon = classTyCon clas + ] $ + + -- Interface type signatures + -- We tie a knot so that the Ids read out of interfaces are in scope + -- when we read their pragmas. + -- What we rely on is that pragmas are typechecked lazily; if + -- any type errors are found (ie there's an inconsistency) + -- we silently discard the pragma + -- We must do this before mkImplicitDataBinds (which comes next), since + -- the latter looks up unpackCStringId, for example, which is usually + -- imported + tcInterfaceSigs unf_env decls `thenTc` \ sig_ids -> + tcExtendGlobalValEnv sig_ids $ + + -- Create any necessary record selector Ids and their bindings + -- "Necessary" includes data and newtype declarations + -- We don't create bindings for dictionary constructors; + -- they are always fully applied, and the bindings are just there + -- to support partial applications + mkImplicitDataBinds tycons `thenTc` \ (data_ids, imp_data_binds) -> + mkImplicitClassBinds classes `thenNF_Tc` \ (cls_ids, imp_cls_binds) -> + + -- Extend the global value environment with + -- (a) constructors + -- (b) record selectors + -- (c) class op selectors + -- (d) default-method ids... where? I can't see where these are + -- put into the envt, and I'm worried that the zonking phase + -- will find they aren't there and complain. + tcExtendGlobalValEnv data_ids $ + tcExtendGlobalValEnv cls_ids $ + + -- foreign import declarations next. + tcForeignImports decls `thenTc` \ (fo_ids, foi_decls) -> + tcExtendGlobalValEnv fo_ids $ -- Value declarations next. -- We also typecheck any extra binds that came out of the "deriving" process - -- trace "tcBinds:" $ - tcBindsAndThen - (\ binds1 (binds2, thing) -> (binds1 `ThenBinds` binds2, thing)) - (get_val_decls decls `ThenBinds` deriv_binds) - ( -- Second pass over instance declarations, + tcTopBindsAndThen + (\ is_rec binds1 (binds2, thing) -> (binds1 `AndMonoBinds` binds2, thing)) + (get_val_decls decls `ThenBinds` deriv_binds) + ( tcGetEnv `thenNF_Tc` \ env -> + tcGetUnique `thenNF_Tc` \ uniq -> + returnTc ((EmptyMonoBinds, env), emptyLIE) + ) `thenTc` \ ((val_binds, final_env), lie_valdecls) -> + tcSetEnv final_env $ + + -- foreign export declarations next. + tcForeignExports decls `thenTc` \ (lie_fodecls, foe_binds, foe_decls) -> + + -- Second pass over class and instance declarations, -- to compile the bindings themselves. - -- trace "tc8" $ - tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) -> - tcClassDecls2 decls `thenNF_Tc` \ (lie_clasdecls, cls_binds) -> - tcCheckMainSig mod_name `thenTc_` - tcGetEnv `thenNF_Tc` \ env -> - returnTc ( (EmptyBinds, (inst_binds, cls_binds, env)), - lie_instdecls `plusLIE` lie_clasdecls - ) - ) + tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) -> + tcClassDecls2 decls `thenNF_Tc` \ (lie_clasdecls, cls_dm_binds) -> + tcRules decls `thenNF_Tc` \ (lie_rules, rules) -> - `thenTc` \ ((val_binds, (inst_binds, cls_binds, final_env)), lie_alldecls) -> - - -- Deal with constant or ambiguous InstIds. How could - -- there be ambiguous ones? They can only arise if a - -- top-level decl falls under the monomorphism - -- restriction, and no subsequent decl instantiates its - -- type. (Usually, ambiguous type variables are resolved - -- during the generalisation step.) - -- trace "tc9" $ - tcSimplifyTop lie_alldecls `thenTc` \ const_insts -> + -- Deal with constant or ambiguous InstIds. How could + -- there be ambiguous ones? They can only arise if a + -- top-level decl falls under the monomorphism + -- restriction, and no subsequent decl instantiates its + -- type. (Usually, ambiguous type variables are resolved + -- during the generalisation step.) + let + lie_alldecls = lie_valdecls `plusLIE` + lie_instdecls `plusLIE` + lie_clasdecls `plusLIE` + lie_fodecls `plusLIE` + lie_rules + in + tcSimplifyTop lie_alldecls `thenTc` \ const_inst_binds -> + + -- Check that Main defines main + (if mod_name == mAIN_Name then + tcLookupValueByKeyMaybe mainKey `thenNF_Tc` \ maybe_main -> + checkTc (maybeToBool maybe_main) noMainErr + else + returnTc () + ) `thenTc_` + + -- Backsubstitution. This must be done last. + -- Even tcSimplifyTop may do some unification. + let + all_binds = imp_data_binds `AndMonoBinds` + imp_cls_binds `AndMonoBinds` + val_binds `AndMonoBinds` + inst_binds `AndMonoBinds` + cls_dm_binds `AndMonoBinds` + const_inst_binds `AndMonoBinds` + foe_binds + in + zonkTopBinds all_binds `thenNF_Tc` \ (all_binds', really_final_env) -> + tcSetValueEnv really_final_env $ + zonkForeignExports foe_decls `thenNF_Tc` \ foe_decls' -> + zonkRules rules `thenNF_Tc` \ rules' -> + + returnTc (really_final_env, + (TcResults { tc_binds = all_binds', + tc_tycons = local_tycons, + tc_classes = local_classes, + tc_insts = inst_info, + tc_fords = foi_decls ++ foe_decls', + tc_rules = rules', + tc_env = really_final_env + })) + ) - -- Backsubstitution. Monomorphic top-level decls may have - -- been instantiated by subsequent decls, and the final - -- simplification step may have instantiated some - -- ambiguous types. So, sadly, we need to back-substitute - -- over the whole bunch of bindings. - -- - -- More horrible still, we have to do it in a careful order, so that - -- all the TcIds are in scope when we come across them. - -- - -- These bindings ought really to be bundled together in a huge - -- recursive group, but HsSyn doesn't have recursion among Binds, only - -- among MonoBinds. Sigh again. - zonkBinds nullTyVarEnv nullIdEnv (MonoBind const_insts [] nonRecursive) - `thenNF_Tc` \ (const_insts', ve1) -> - zonkBinds nullTyVarEnv ve1 val_binds `thenNF_Tc` \ (val_binds', ve2) -> - - zonkBinds nullTyVarEnv ve2 data_binds `thenNF_Tc` \ (data_binds', _) -> - zonkBinds nullTyVarEnv ve2 inst_binds `thenNF_Tc` \ (inst_binds', _) -> - zonkBinds nullTyVarEnv ve2 cls_binds `thenNF_Tc` \ (cls_binds', _) -> - - let - localids = getEnv_LocalIds final_env - tycons = getEnv_TyCons final_env - classes = getEnv_Classes final_env - - local_tycons = filter isLocallyDefined tycons - local_classes = filter isLocallyDefined classes - in - -- FINISHED AT LAST - returnTc ( - (data_binds', cls_binds', inst_binds', val_binds', const_insts'), - - local_tycons, local_classes, inst_info, tycon_specs, - - ddump_deriv - ))) + -- End of outer fix loop + ) `thenTc` \ (final_env, stuff) -> + returnTc stuff get_val_decls decls = foldr ThenBinds EmptyBinds [binds | ValD binds <- decls] \end{code} \begin{code} -tcCheckMainSig mod_name - | not is_main && not is_ghc_main - = returnTc () -- A non-main module - - | otherwise - = -- Check that main is defined - tcLookupTyCon tycon_name `thenTc` \ (_,_,tycon) -> - tcLookupLocalValue main_name `thenNF_Tc` \ maybe_main_id -> - case maybe_main_id of { - Nothing -> failTc (noMainErr mod_name main_name); - Just main_id -> - - -- Check that it has the right type (or a more general one) - let - expected_ty | isSynTyCon tycon = mkSynTy tycon [unitTy] - | otherwise = applyTyCon tycon [unitTy] - -- This is bizarre. There ought to be a suitable function in Type.lhs! - in - tcInstType [] expected_ty `thenNF_Tc` \ expected_tau -> - tcId main_name `thenNF_Tc` \ (_, lie, main_tau) -> - tcSetErrCtxt (mainTyCheckCtxt main_name) $ - unifyTauTy expected_tau - main_tau `thenTc_` - checkTc (isEmptyBag lie) (mainTyMisMatch main_name expected_ty (idType main_id)) - } - where - is_main = mod_name == mAIN - is_ghc_main = mod_name == gHC_MAIN - - main_name | is_main = main_NAME - | otherwise = mainPrimIO_NAME - - tycon_name | is_main = ioTyCon_NAME - | otherwise = primIoTyCon_NAME - -mainTyCheckCtxt main_name sty - = hsep [ptext SLIT("When checking that"), ppr sty main_name, ptext SLIT("has the required type")] - -noMainErr mod_name main_name sty - = hsep [ptext SLIT("Module"), pprModule sty mod_name, - ptext SLIT("must include a definition for"), ppr sty main_name] - -mainTyMisMatch :: Name -> Type -> TcType s -> Error -mainTyMisMatch main_name expected actual sty - = hang (hsep [ppr sty main_name, ptext SLIT("has the wrong type")]) - 4 (vcat [ - hsep [ptext SLIT("Expected:"), ppr sty expected], - hsep [ptext SLIT("Inferred:"), ppr sty actual] - ]) +noMainErr + = hsep [ptext SLIT("Module"), quotes (pprModuleName mAIN_Name), + ptext SLIT("must include a definition for"), quotes (ptext SLIT("main"))] \end{code} +