X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcTyDecls.lhs;h=bde665527a38cb7682abcf8eed73238b575dd50c;hb=d68887047bcfb9021151f768fe1a22df2d3fbe1e;hp=1a3c2c3e63712e1e7e87ffdb13811a15237b7d14;hpb=266fadd93461d4317967df08cd641e965cd8769a;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcTyDecls.lhs b/ghc/compiler/typecheck/TcTyDecls.lhs index 1a3c2c3..bde6655 100644 --- a/ghc/compiler/typecheck/TcTyDecls.lhs +++ b/ghc/compiler/typecheck/TcTyDecls.lhs @@ -5,100 +5,45 @@ \begin{code} module TcTyDecls ( - tcTyDecl, kcTyDecl, - tcConDecl, - mkDataBinds + tcTyDecl1, kcConDetails, mkNewTyConRep ) where #include "HsVersions.h" -import HsSyn ( MonoBinds(..), - TyClDecl(..), ConDecl(..), ConDetails(..), BangType(..), - andMonoBindList +import HsSyn ( TyClDecl(..), ConDecl(..), ConDetails(..), BangType(..), + getBangType, conDetailsTys ) -import RnHsSyn ( RenamedTyClDecl, RenamedConDecl ) -import TcHsSyn ( TcMonoBinds ) -import BasicTypes ( RecFlag(..), NewOrData(..) ) +import RnHsSyn ( RenamedTyClDecl, RenamedConDecl, RenamedContext ) +import BasicTypes ( NewOrData(..), RecFlag, isRec ) -import TcMonoType ( tcExtendTopTyVarScope, tcExtendTyVarScope, - tcHsTypeKind, tcHsType, tcHsTopType, tcHsTopBoxedType, - tcContext, tcHsTopTypeKind +import TcMonoType ( tcHsRecType, tcHsTyVars, tcRecTheta, + kcHsContext, kcHsSigType, kcHsLiftedSigType + ) +import TcEnv ( tcExtendTyVarEnv, + tcLookupTyCon, tcLookupRecId, + TyThingDetails(..), RecTcEnv ) -import TcType ( zonkTcTyVarToTyVar, zonkTcClassConstraints ) -import TcEnv ( tcLookupTy, TcTyThing(..) ) import TcMonad -import TcUnify ( unifyKind ) -import Class ( Class ) -import DataCon ( DataCon, dataConSig, mkDataCon, isNullaryDataCon, - dataConFieldLabels, dataConId, - markedStrict, notMarkedStrict, markedUnboxed +import DataCon ( DataCon, mkDataCon, dataConFieldLabels, markedStrict, + notMarkedStrict, markedUnboxed, dataConRepType ) -import MkId ( mkDataConId, mkRecordSelId, mkNewTySelId ) -import Id ( getIdUnfolding ) -import CoreUnfold ( unfoldingTemplate ) +import MkId ( mkDataConId, mkDataConWrapId, mkRecordSelId ) import FieldLabel -import Var ( Id, TyVar ) -import Name ( Name, isLocallyDefined, OccName, NamedThing(..), nameUnique ) +import Var ( TyVar ) +import Name ( Name, NamedThing(..) ) import Outputable -import TyCon ( TyCon, ArgVrcs, mkSynTyCon, mkAlgTyCon, isAlgTyCon, - isSynTyCon, tyConDataCons, isNewTyCon - ) -import Type ( getTyVar, tyVarsOfTypes, - mkTyConApp, mkTyVarTys, mkForAllTys, mkFunTy, - mkTyVarTy, - mkArrowKind, mkArrowKinds, boxedTypeKind, - isUnboxedType, Type, ThetaType, classesOfPreds +import TyCon ( TyCon, isNewTyCon, tyConTyVars ) +import Type ( tyVarsOfTypes, tyVarsOfPred, splitFunTy, applyTys, + mkTyConApp, mkTyVarTys, mkForAllTys, + splitAlgTyConApp_maybe, Type, ThetaType ) -import Var ( tyVarKind ) +import TysWiredIn ( unitTy ) import VarSet ( intersectVarSet, isEmptyVarSet ) -import Util ( equivClasses ) -import FiniteMap ( FiniteMap, lookupWithDefaultFM ) -\end{code} - -%************************************************************************ -%* * -\subsection{Kind checking} -%* * -%************************************************************************ - -\begin{code} -kcTyDecl :: RenamedTyClDecl -> TcM s () - -kcTyDecl (TySynonym name tyvar_names rhs src_loc) - = tcLookupTy name `thenNF_Tc` \ (kind, _, _) -> - tcExtendTopTyVarScope kind tyvar_names $ \ _ result_kind -> - tcHsTypeKind rhs `thenTc` \ (rhs_kind, _) -> - unifyKind result_kind rhs_kind - -kcTyDecl (TyData _ context tycon_name tyvar_names con_decls _ _ src_loc) - = tcLookupTy tycon_name `thenNF_Tc` \ (kind, _, _) -> - tcExtendTopTyVarScope kind tyvar_names $ \ result_kind _ -> - tcContext context `thenTc_` - mapTc kcConDecl con_decls `thenTc_` - returnTc () - -kcConDecl (ConDecl _ ex_tvs ex_ctxt details loc) - = tcAddSrcLoc loc ( - tcExtendTyVarScope ex_tvs ( \ tyvars -> - tcContext ex_ctxt `thenTc_` - kc_con details `thenTc_` - returnTc () - )) - where - kc_con (VanillaCon btys) = mapTc kc_bty btys `thenTc_` returnTc () - kc_con (InfixCon bty1 bty2) = mapTc kc_bty [bty1,bty2] `thenTc_` returnTc () - kc_con (NewCon ty _) = tcHsType ty `thenTc_` returnTc () - kc_con (RecCon flds) = mapTc kc_field flds `thenTc_` returnTc () - - kc_bty (Banged ty) = tcHsType ty - kc_bty (Unbanged ty) = tcHsType ty - kc_bty (Unpacked ty) = tcHsType ty - - kc_field (_, bty) = kc_bty bty +import PrelNames ( unpackCStringName, unpackCStringUtf8Name ) +import ListSetOps ( equivClasses ) \end{code} - %************************************************************************ %* * \subsection{Type checking} @@ -106,133 +51,127 @@ kcConDecl (ConDecl _ ex_tvs ex_ctxt details loc) %************************************************************************ \begin{code} -tcTyDecl :: RecFlag -> FiniteMap Name ArgVrcs -> RenamedTyClDecl -> TcM s TyCon - -tcTyDecl is_rec rec_vrcs (TySynonym tycon_name tyvar_names rhs src_loc) - = tcLookupTy tycon_name `thenNF_Tc` \ (tycon_kind, Just arity, _) -> - tcExtendTopTyVarScope tycon_kind tyvar_names $ \ tyvars _ -> - tcHsTopTypeKind rhs `thenTc` \ (_, rhs_ty) -> +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) $ + 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 + -- quantify over them: + -- e.g. type T = a->a + -- will become type T = forall a. a->a + -- + -- With gla-exts that's right, but for H98 we should complain. + -- We can now do that here without falling into + -- a black hole, we still do it in rnDecl (TySynonym case) + + returnTc (tycon_name, SynTyDetails rhs_ty) + +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 - -- Construct the tycon - argvrcs = lookupWithDefaultFM rec_vrcs (pprPanic "tcTyDecl: argvrcs:" $ ppr tycon_name) - tycon_name - tycon = mkSynTyCon tycon_name tycon_kind arity tyvars rhs_ty argvrcs + tyvars = tyConTyVars tycon in - returnTc tycon - - -tcTyDecl is_rec rec_vrcs (TyData data_or_new context tycon_name tyvar_names con_decls derivings pragmas src_loc) - = -- Lookup the pieces - tcLookupTy tycon_name `thenNF_Tc` \ (tycon_kind, _, ATyCon rec_tycon) -> - tcExtendTopTyVarScope tycon_kind tyvar_names $ \ tyvars _ -> + tcExtendTyVarEnv tyvars $ -- Typecheck the pieces - tcContext context `thenTc` \ ctxt -> - let ctxt' = classesOfPreds ctxt in - mapTc (tcConDecl rec_tycon tyvars ctxt') con_decls `thenTc` \ data_cons -> - tc_derivs derivings `thenTc` \ derived_classes -> + 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) +\end{code} - let - -- Construct the tycon - real_data_or_new = case data_or_new of - NewType -> NewType - DataType | all isNullaryDataCon data_cons -> EnumType - | otherwise -> DataType - - argvrcs = lookupWithDefaultFM rec_vrcs (pprPanic "tcTyDecl: argvrcs:" $ ppr tycon_name) - tycon_name - - tycon = mkAlgTyCon tycon_name tycon_kind tyvars ctxt' argvrcs - data_cons - derived_classes - Nothing -- Not a dictionary - real_data_or_new is_rec - in - returnTc tycon - where - tc_derivs Nothing = returnTc [] - tc_derivs (Just ds) = mapTc tc_deriv ds +\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 - tc_deriv name = tcLookupTy name `thenTc` \ (_, _, AClass clas) -> - returnTc clas +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 + } \end{code} %************************************************************************ %* * -\subsection{Type check constructors} +\subsection{Kind and type check constructors} %* * %************************************************************************ \begin{code} -tcConDecl :: TyCon -> [TyVar] -> [(Class,[Type])] -> RenamedConDecl -> TcM s DataCon - -tcConDecl tycon tyvars ctxt (ConDecl name ex_tvs ex_ctxt details src_loc) - = tcAddSrcLoc src_loc $ - tcExtendTyVarScope ex_tvs $ \ ex_tyvars -> - tcContext ex_ctxt `thenTc` \ ex_theta -> - let ex_ctxt' = classesOfPreds ex_theta in - tc_con_decl_help tycon tyvars ctxt name ex_tyvars ex_ctxt' details - -tc_con_decl_help tycon tyvars ctxt name ex_tyvars ex_theta details - = case details of - VanillaCon btys -> tc_datacon btys - InfixCon bty1 bty2 -> tc_datacon [bty1,bty2] - NewCon ty mb_f -> tc_newcon ty mb_f - RecCon fields -> tc_rec_con fields +kcConDetails :: NewOrData -> RenamedContext -> ConDetails Name -> TcM () +kcConDetails new_or_data ex_ctxt details + = kcHsContext ex_ctxt `thenTc_` + mapTc_ kc_sig_type (conDetailsTys details) + where + 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. + + +tcConDecl :: RecFlag -> NewOrData -> TyCon -> [TyVar] -> ThetaType -> RenamedConDecl -> TcM DataCon + +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_datacon btys + tc_datacon ex_tyvars ex_theta btys = let - arg_stricts = map get_strictness btys - tys = map get_pty btys + arg_stricts = map getBangStrictness btys + tys = map getBangType btys in - mapTc tcHsTopType tys `thenTc` \ arg_tys -> - mk_data_con arg_stricts arg_tys [] + mapTc (tcHsRecType is_rec) tys `thenTc` \ arg_tys -> + mk_data_con ex_tyvars ex_theta arg_stricts arg_tys [] - tc_newcon ty mb_f - = tcHsTopBoxedType ty `thenTc` \ arg_ty -> - -- can't allow an unboxed type here, because we're effectively - -- going to remove the constructor while coercing it to a boxed type. - let - field_label = - case mb_f of - Nothing -> [] - Just f -> [mkFieldLabel (getName f) arg_ty (head allFieldLabelTags)] - in - mk_data_con [notMarkedStrict] [arg_ty] field_label - - tc_rec_con fields - = checkTc (null ex_tyvars) (exRecConErr name) `thenTc_` - mapTc tc_field fields `thenTc` \ field_label_infos_s -> + tc_rec_con ex_tyvars ex_theta fields + = checkTc (null ex_tyvars) (exRecConErr name) `thenTc_` + mapTc tc_field (fields `zip` allFieldLabelTags) `thenTc` \ field_labels_s -> let - field_label_infos = concat field_label_infos_s - arg_stricts = [strict | (_, _, strict) <- field_label_infos] - arg_tys = [ty | (_, ty, _) <- field_label_infos] - - field_labels = [ mkFieldLabel (getName name) ty tag - | ((name, ty, _), tag) <- field_label_infos `zip` allFieldLabelTags ] + 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 + ] in - mk_data_con arg_stricts arg_tys field_labels - - tc_field (field_label_names, bty) - = tcHsTopType (get_pty bty) `thenTc` \ field_ty -> - returnTc [(name, field_ty, get_strictness bty) | name <- field_label_names] - - mk_data_con arg_stricts arg_tys fields - = -- Now we've checked all the field types we must - -- zonk the existential tyvars to finish the kind - -- inference on their kinds, and commit them to being - -- immutable type variables. (The top-level tyvars are - -- already fixed, by the preceding kind-inference pass.) - mapNF_Tc zonkTcTyVarToTyVar ex_tyvars `thenNF_Tc` \ ex_tyvars' -> - zonkTcClassConstraints ex_theta `thenNF_Tc` \ ex_theta' -> - let + mk_data_con ex_tyvars ex_theta arg_stricts + (map fieldLabelType field_labels) field_labels + + tc_field ((field_label_names, bty), tag) + = 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 + = let data_con = mkDataCon name arg_stricts fields tyvars (thinContext arg_tys ctxt) - ex_tyvars' ex_theta' + ex_tyvars ex_theta arg_tys - tycon data_con_id - data_con_id = mkDataConId data_con + tycon data_con_id data_con_wrap_id + + data_con_id = mkDataConId wkr_name data_con + data_con_wrap_id = mkDataConWrapId data_con in returnNF_Tc data_con @@ -242,98 +181,68 @@ 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 - -get_strictness (Banged _) = markedStrict -get_strictness (Unbanged _) = notMarkedStrict -get_strictness (Unpacked _) = markedUnboxed - -get_pty (Banged ty) = ty -get_pty (Unbanged ty) = ty -get_pty (Unpacked ty) = ty -\end{code} + in_arg_tys pred = not $ isEmptyVarSet $ + tyVarsOfPred pred `intersectVarSet` arg_tyvars +getBangStrictness (Banged _) = markedStrict +getBangStrictness (Unbanged _) = notMarkedStrict +getBangStrictness (Unpacked _) = markedUnboxed +\end{code} %************************************************************************ %* * -\subsection{Generating constructor/selector bindings for data declarations} +\subsection{Record selectors} %* * %************************************************************************ \begin{code} -mkDataBinds :: [TyCon] -> TcM s ([Id], TcMonoBinds) -mkDataBinds [] = returnTc ([], EmptyMonoBinds) -mkDataBinds (tycon : tycons) - | isSynTyCon tycon = mkDataBinds tycons - | otherwise = mkDataBinds_one tycon `thenTc` \ (ids1, b1) -> - mkDataBinds tycons `thenTc` \ (ids2, b2) -> - returnTc (ids1++ids2, b1 `AndMonoBinds` b2) - -mkDataBinds_one tycon - = mapTc (mkRecordSelector tycon) groups `thenTc` \ sel_ids -> - let - data_ids = map dataConId data_cons ++ sel_ids - - -- For the locally-defined things - -- we need to turn the unfoldings inside the Ids into bindings, - binds | isLocallyDefined tycon - = [ CoreMonoBind data_id (unfoldingTemplate (getIdUnfolding data_id)) - | data_id <- data_ids, isLocallyDefined data_id - ] - | otherwise - = [] - in - returnTc (data_ids, andMonoBindList 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 = tyConDataCons tycon - 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 (== 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_` - returnTc selector_id - where - field_ty = fieldLabelType first_field_label - field_name = fieldLabelName first_field_label - other_tys = [fieldLabelType fl | (_, fl) <- other_fields] - (tyvars, _, _, _, _, _) = dataConSig first_con - data_ty = mkTyConApp tycon (mkTyVarTys tyvars) - -- tyvars of first_con may be free in field_ty - -- Now build the selector - - selector_ty :: Type - selector_ty = mkForAllTys tyvars $ - mkFunTy data_ty $ - field_ty - - selector_id :: Id - selector_id - | isNewTyCon tycon = mkNewTySelId first_field_label selector_ty - | otherwise = mkRecordSelId first_field_label selector_ty -\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")