X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcTyDecls.lhs;h=9ab566143ce0c0f6580414efdbebcb4a2f145b32;hb=c4786b4eb8481d3dbda8ba49f675e6d1958d6d18;hp=2281538175eb1037f0312aeb41c85299d9323175;hpb=710e207487929c4a5977b5ee3bc6e539091953db;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcTyDecls.lhs b/ghc/compiler/typecheck/TcTyDecls.lhs index 2281538..9ab5661 100644 --- a/ghc/compiler/typecheck/TcTyDecls.lhs +++ b/ghc/compiler/typecheck/TcTyDecls.lhs @@ -4,48 +4,35 @@ \section[TcTyDecls]{Typecheck type declarations} \begin{code} -module TcTyDecls ( - tcTyDecl1, - kcConDetails, - mkImplicitDataBinds, mkNewTyConRep - ) where +module TcTyDecls ( tcTyDecl1, kcConDetails ) where #include "HsVersions.h" -import HsSyn ( MonoBinds(..), - TyClDecl(..), ConDecl(..), ConDetails(..), BangType(..), - getBangType +import HsSyn ( TyClDecl(..), ConDecl(..), ConDetails(..), + getBangType, getBangStrictness, conDetailsTys ) import RnHsSyn ( RenamedTyClDecl, RenamedConDecl, RenamedContext ) -import TcHsSyn ( TcMonoBinds, idsToMonoBinds ) -import BasicTypes ( NewOrData(..) ) +import BasicTypes ( NewOrData(..), RecFlag, isRec ) -import TcMonoType ( tcHsType, tcHsSigType, tcHsBoxedSigType, tcHsTyVars, tcClassContext, - kcHsContext, kcHsSigType +import TcMonoType ( tcHsRecType, tcHsTyVars, tcRecTheta, + kcHsContext, kcHsSigType, kcHsLiftedSigType ) -import TcEnv ( tcExtendTyVarEnv, tcLookupTy, tcLookupValueByKey, TyThing(..), TyThingDetails(..) ) +import TcEnv ( tcExtendTyVarEnv, + tcLookupTyCon, tcLookupRecId, + TyThingDetails(..), RecTcEnv + ) +import TcType ( tcEqType, tyVarsOfTypes, tyVarsOfPred, Type, ThetaType ) import TcMonad -import Class ( ClassContext ) -import DataCon ( DataCon, mkDataCon, - dataConFieldLabels, dataConId, dataConWrapId, - markedStrict, notMarkedStrict, markedUnboxed, dataConRepType - ) +import DataCon ( DataCon, mkDataCon, dataConFieldLabels ) import MkId ( mkDataConId, mkDataConWrapId, mkRecordSelId ) import FieldLabel -import Var ( Id, TyVar ) -import Name ( Name, isLocallyDefined, NamedThing(..) ) +import Var ( TyVar ) +import Name ( Name, NamedThing(..) ) import Outputable -import TyCon ( TyCon, isSynTyCon, isNewTyCon, - tyConDataConsIfAvailable, tyConTyVars, tyConGenIds - ) -import Type ( tyVarsOfTypes, splitFunTy, applyTys, - mkTyConApp, mkTyVarTys, mkForAllTys, - splitAlgTyConApp_maybe, Type - ) -import TysWiredIn ( unitTy ) +import TyCon ( TyCon, tyConTyVars ) import VarSet ( intersectVarSet, isEmptyVarSet ) -import PrelNames ( unpackCStringIdKey, unpackCStringUtf8IdKey ) +import PrelNames ( unpackCStringName, unpackCStringUtf8Name ) import ListSetOps ( equivClasses ) \end{code} @@ -56,12 +43,12 @@ import ListSetOps ( equivClasses ) %************************************************************************ \begin{code} -tcTyDecl1 :: RenamedTyClDecl -> TcM s (Name, TyThingDetails) -tcTyDecl1 (TySynonym tycon_name tyvar_names rhs src_loc) - = tcLookupTy tycon_name `thenNF_Tc` \ (ATyCon tycon) -> +tcTyDecl1 :: RecFlag -> RecTcEnv -> RenamedTyClDecl -> TcM (Name, TyThingDetails) +tcTyDecl1 is_rec unf_env (TySynonym {tcdName = tycon_name, tcdSynRhs = rhs}) + = tcLookupTyCon tycon_name `thenNF_Tc` \ tycon -> tcExtendTyVarEnv (tyConTyVars tycon) $ - tcHsType rhs `thenTc` \ rhs_ty -> - -- Note tcHsType not tcHsSigType; we allow type synonyms + tcHsRecType is_rec rhs `thenTc` \ rhs_ty -> + -- Note tcHsRecType not tcHsRecSigType; we allow type synonyms -- that aren't types; e.g. type List = [] -- -- If the RHS mentions tyvars that aren't in scope, we'll @@ -75,46 +62,22 @@ tcTyDecl1 (TySynonym tycon_name tyvar_names rhs src_loc) returnTc (tycon_name, SynTyDetails rhs_ty) -tcTyDecl1 (TyData new_or_data context tycon_name _ con_decls _ derivings _ src_loc name1 name2) - = tcLookupTy tycon_name `thenNF_Tc` \ (ATyCon tycon) -> +tcTyDecl1 is_rec unf_env (TyData {tcdND = new_or_data, tcdCtxt = context, + tcdName = tycon_name, tcdCons = con_decls}) + = tcLookupTyCon tycon_name `thenNF_Tc` \ tycon -> let tyvars = tyConTyVars tycon in tcExtendTyVarEnv tyvars $ -- Typecheck the pieces - tcClassContext context `thenTc` \ ctxt -> - tc_derivs derivings `thenTc` \ derived_classes -> - mapTc (tcConDecl new_or_data tycon tyvars ctxt) con_decls `thenTc` \ data_cons -> + tcRecTheta is_rec context `thenTc` \ ctxt -> + mapTc (tcConDecl is_rec new_or_data tycon tyvars ctxt) con_decls `thenTc` \ data_cons -> + tcRecordSelectors is_rec unf_env tycon data_cons `thenTc` \ sel_ids -> + returnTc (tycon_name, DataTyDetails ctxt data_cons sel_ids) - returnTc (tycon_name, DataTyDetails ctxt data_cons derived_classes) - where - tc_derivs Nothing = returnTc [] - tc_derivs (Just ds) = mapTc tc_deriv ds - - tc_deriv name = tcLookupTy name `thenTc` \ (AClass clas) -> - returnTc clas -\end{code} - -\begin{code} -mkNewTyConRep :: TyCon -> Type --- Find the representation type for this newtype TyCon --- The trick is to to deal correctly with recursive newtypes --- such as newtype T = MkT T - -mkNewTyConRep tc - = mkForAllTys tvs (loop [] (mkTyConApp tc (mkTyVarTys tvs))) - where - tvs = tyConTyVars tc - loop tcs ty = case splitAlgTyConApp_maybe ty of { - Nothing -> ty ; - Just (tc, tys, data_cons) | not (isNewTyCon tc) -> ty - | tc `elem` tcs -> unitTy - | otherwise -> - - case splitFunTy (applyTys (dataConRepType (head data_cons)) tys) of - (rep_ty, _) -> loop (tc:tcs) rep_ty - } +tcTyDecl1 is_rec unf_env (ForeignType {tcdName = tycon_name}) + = returnTc (tycon_name, ForeignTyDetails) \end{code} @@ -125,42 +88,35 @@ mkNewTyConRep tc %************************************************************************ \begin{code} -kcConDetails :: RenamedContext -> ConDetails Name -> TcM s () -kcConDetails ex_ctxt details +kcConDetails :: NewOrData -> RenamedContext -> ConDetails Name -> TcM () +kcConDetails new_or_data ex_ctxt details = kcHsContext ex_ctxt `thenTc_` - kc_con_details details + mapTc_ kc_sig_type (conDetailsTys details) where - kc_con_details (VanillaCon btys) = mapTc_ kc_bty btys - kc_con_details (InfixCon bty1 bty2) = mapTc_ kc_bty [bty1,bty2] - kc_con_details (RecCon flds) = mapTc_ kc_field flds - - kc_field (_, bty) = kc_bty bty + kc_sig_type = case new_or_data of + DataType -> kcHsSigType + NewType -> kcHsLiftedSigType + -- Can't allow an unlifted type here, because we're effectively + -- going to remove the constructor while coercing it to a lifted type. - kc_bty bty = kcHsSigType (getBangType bty) -tcConDecl :: NewOrData -> TyCon -> [TyVar] -> ClassContext -> RenamedConDecl -> TcM s DataCon +tcConDecl :: RecFlag -> NewOrData -> TyCon -> [TyVar] -> ThetaType -> RenamedConDecl -> TcM DataCon -tcConDecl new_or_data tycon tyvars ctxt (ConDecl name wkr_name ex_tvs ex_ctxt details src_loc) - = tcAddSrcLoc src_loc $ - tcHsTyVars ex_tvs (kcConDetails ex_ctxt details) $ \ ex_tyvars -> - tcClassContext ex_ctxt `thenTc` \ ex_theta -> +tcConDecl is_rec new_or_data tycon tyvars ctxt (ConDecl name wkr_name ex_tvs ex_ctxt details src_loc) + = tcAddSrcLoc src_loc $ + tcHsTyVars ex_tvs (kcConDetails new_or_data ex_ctxt details) $ \ ex_tyvars -> + tcRecTheta is_rec ex_ctxt `thenTc` \ ex_theta -> case details of VanillaCon btys -> tc_datacon ex_tyvars ex_theta btys InfixCon bty1 bty2 -> tc_datacon ex_tyvars ex_theta [bty1,bty2] RecCon fields -> tc_rec_con ex_tyvars ex_theta fields where - tc_sig_type = case new_or_data of - DataType -> tcHsSigType - NewType -> tcHsBoxedSigType - -- Can't allow an unboxed type here, because we're effectively - -- going to remove the constructor while coercing it to a boxed type. - tc_datacon ex_tyvars ex_theta btys = let arg_stricts = map getBangStrictness btys tys = map getBangType btys in - mapTc tc_sig_type tys `thenTc` \ arg_tys -> + mapTc (tcHsRecType is_rec) tys `thenTc` \ arg_tys -> mk_data_con ex_tyvars ex_theta arg_stricts arg_tys [] tc_rec_con ex_tyvars ex_theta fields @@ -169,15 +125,15 @@ tcConDecl new_or_data tycon tyvars ctxt (ConDecl name wkr_name ex_tvs ex_ctxt de let field_labels = concat field_labels_s arg_stricts = [str | (ns, bty) <- fields, - let str = getBangStrictness bty, - n <- ns -- One for each. E.g x,y,z :: !Int + let str = getBangStrictness bty, + n <- ns -- One for each. E.g x,y,z :: !Int ] in mk_data_con ex_tyvars ex_theta arg_stricts (map fieldLabelType field_labels) field_labels tc_field ((field_label_names, bty), tag) - = tc_sig_type (getBangType bty) `thenTc` \ field_ty -> + = tcHsRecType is_rec (getBangType bty) `thenTc` \ field_ty -> returnTc [mkFieldLabel (getName name) tycon field_ty tag | name <- field_label_names] mk_data_con ex_tyvars ex_theta arg_stricts arg_tys fields @@ -199,85 +155,64 @@ thinContext arg_tys ctxt = filter in_arg_tys ctxt where arg_tyvars = tyVarsOfTypes arg_tys - in_arg_tys (clas,tys) = not $ isEmptyVarSet $ - tyVarsOfTypes tys `intersectVarSet` arg_tyvars - -getBangStrictness (Banged _) = markedStrict -getBangStrictness (Unbanged _) = notMarkedStrict -getBangStrictness (Unpacked _) = markedUnboxed + in_arg_tys pred = not $ isEmptyVarSet $ + tyVarsOfPred pred `intersectVarSet` arg_tyvars \end{code} - %************************************************************************ %* * -\subsection{Generating constructor/selector bindings for data declarations} +\subsection{Record selectors} %* * %************************************************************************ \begin{code} -mkImplicitDataBinds :: [TyCon] -> TcM s ([Id], TcMonoBinds) -mkImplicitDataBinds [] = returnTc ([], EmptyMonoBinds) -mkImplicitDataBinds (tycon : tycons) - | isSynTyCon tycon = mkImplicitDataBinds tycons - | otherwise = mkImplicitDataBinds_one tycon `thenTc` \ (ids1, b1) -> - mkImplicitDataBinds tycons `thenTc` \ (ids2, b2) -> - returnTc (ids1++ids2, b1 `AndMonoBinds` b2) - -mkImplicitDataBinds_one tycon - = mapTc (mkRecordSelector tycon) groups `thenTc` \ sel_ids -> - let - unf_ids = sel_ids ++ data_con_wrapper_ids ++ gen_ids - all_ids = map dataConId data_cons ++ unf_ids - - -- For the locally-defined things - -- we need to turn the unfoldings inside the selector Ids into bindings, - -- and build bindigns for the constructor wrappers - binds | isLocallyDefined tycon = idsToMonoBinds unf_ids - | otherwise = EmptyMonoBinds - in - returnTc (all_ids, binds) +tcRecordSelectors is_rec unf_env tycon data_cons + -- Omit the check that the fields have consistent types if + -- the group is recursive; TcTyClsDecls.tcGroup will repeat + -- with NonRecursive once we have tied the knot + | isRec is_rec = returnTc sel_ids + | otherwise = mapTc check groups `thenTc_` + returnTc sel_ids where - data_cons = tyConDataConsIfAvailable tycon - -- Abstract types mean we don't bring the - -- data cons into scope, which should be fine - gen_ids = tyConGenIds tycon - data_con_wrapper_ids = map dataConWrapId data_cons - - fields = [ (con, field) | con <- data_cons, - field <- dataConFieldLabels con - ] + fields = [ field | con <- data_cons + , field <- dataConFieldLabels con ] -- groups is list of fields that share a common name - groups = equivClasses cmp_name fields - cmp_name (_, field1) (_, field2) - = fieldLabelName field1 `compare` fieldLabelName field2 + groups = equivClasses cmp_name fields + cmp_name field1 field2 = fieldLabelName field1 `compare` fieldLabelName field2 + + sel_ids = [ mkRecordSelId tycon field unpack_id unpackUtf8_id + | (field : _) <- groups ] + + check fields@(first_field_label : other_fields) + -- These fields all have the same name, but are from + -- different constructors in the data type + = -- Check that all the fields in the group have the same type + -- NB: this check assumes that all the constructors of a given + -- data type use the same type variables + checkTc (all (tcEqType field_ty) other_tys) (fieldTypeMisMatch field_name) + where + field_ty = fieldLabelType first_field_label + field_name = fieldLabelName first_field_label + other_tys = map fieldLabelType other_fields + + unpack_id = tcLookupRecId unf_env unpackCStringName + unpackUtf8_id = tcLookupRecId unf_env unpackCStringUtf8Name \end{code} -\begin{code} -mkRecordSelector tycon fields@((first_con, first_field_label) : other_fields) - -- These fields all have the same name, but are from - -- different constructors in the data type - -- Check that all the fields in the group have the same type - -- This check assumes that all the constructors of a given - -- data type use the same type variables - = checkTc (all (== field_ty) other_tys) - (fieldTypeMisMatch field_name) `thenTc_` - tcLookupValueByKey unpackCStringIdKey `thenTc` \ unpack_id -> - tcLookupValueByKey unpackCStringUtf8IdKey `thenTc` \ unpackUtf8_id -> - returnTc (mkRecordSelId tycon first_field_label unpack_id unpackUtf8_id) - where - field_ty = fieldLabelType first_field_label - field_name = fieldLabelName first_field_label - other_tys = [fieldLabelType fl | (_, fl) <- other_fields] -\end{code} -Errors and contexts -~~~~~~~~~~~~~~~~~~~ +%************************************************************************ +%* * +\subsection{Errors and contexts} +%* * +%************************************************************************ + + \begin{code} fieldTypeMisMatch field_name - = sep [ptext SLIT("Declared types differ for field"), quotes (ppr field_name)] + = sep [ptext SLIT("Different constructors give different types for field"), quotes (ppr field_name)] exRecConErr name = ptext SLIT("Can't combine named fields with locally-quantified type variables")