X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcTyDecls.lhs;h=0ed2fef7421f5bf540b62757d5643918b01fb143;hb=711e4d7a4d65472a3a1fb35bcad8e1c9a109c728;hp=83a4c96732fdc6e93592cf0ec6617d3e272ff21e;hpb=6c381e873e222417d9a67aeec77b9555eca7b7a8;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcTyDecls.lhs b/ghc/compiler/typecheck/TcTyDecls.lhs index 83a4c96..0ed2fef 100644 --- a/ghc/compiler/typecheck/TcTyDecls.lhs +++ b/ghc/compiler/typecheck/TcTyDecls.lhs @@ -1,211 +1,241 @@ % -% (c) The AQUA Project, Glasgow University, 1996 +% (c) The AQUA Project, Glasgow University, 1996-1998 % \section[TcTyDecls]{Typecheck type declarations} \begin{code} -#include "HsVersions.h" - -module TcTyDecls ( - tcTyDecl, - tcConDecl - ) where - -import Ubiq{-uitous-} +module TcTyDecls ( tcTyDecl, checkValidTyCon, kcConDetails ) where -import HsSyn ( TyDecl(..), ConDecl(..), BangType(..), MonoType ) -import RnHsSyn ( RenamedTyDecl(..), RenamedConDecl(..) ) +#include "HsVersions.h" -import TcMonoType ( tcMonoTypeKind, tcMonoType, tcContext ) -import TcEnv ( tcLookupTyCon, tcLookupTyVar, tcLookupClass ) +import HsSyn ( TyClDecl(..), ConDecl(..), ConDetails(..), + getBangType, getBangStrictness, conDetailsTys + ) +import RnHsSyn ( RenamedTyClDecl, RenamedConDecl, RenamedContext ) +import BasicTypes ( NewOrData(..) ) + +import TcMonoType ( tcHsTyVars, tcHsTheta, tcHsType, + kcHsContext, kcHsSigType, kcHsLiftedSigType + ) +import TcEnv ( tcExtendTyVarEnv, + tcLookupTyCon, tcLookupRecId, + TyThingDetails(..), RecTcEnv + ) +import TcType ( tcEqType, tyVarsOfTypes, tyVarsOfPred, ThetaType ) +import TcMType ( checkValidType, UserTypeCtxt(..), checkValidTheta, SourceTyCtxt(..) ) import TcMonad -import TcKind ( TcKind, unifyKind, mkTcArrowKind, mkTcTypeKind ) - -import Id ( mkDataCon, StrictnessMark(..) ) -import Kind ( Kind, mkArrowKind, mkBoxedTypeKind ) -import SpecEnv ( SpecEnv(..), nullSpecEnv ) -import Name ( getNameFullName, Name(..) ) -import Pretty -import TyCon ( TyCon, ConsVisible(..), NewOrData(..), mkSynTyCon, mkDataTyCon ) -import Type ( getTypeKind ) -import TyVar ( getTyVarKind ) -import Util ( panic ) +import DataCon ( DataCon, mkDataCon, dataConFieldLabels, dataConWrapId, dataConName ) +import MkId ( mkDataConId, mkDataConWrapId, mkRecordSelId ) +import FieldLabel +import Var ( TyVar, idType ) +import Name ( Name, NamedThing(..) ) +import Outputable +import TyCon ( TyCon, DataConDetails(..), visibleDataCons, + tyConName, tyConTheta, getSynTyConDefn, + tyConTyVars, tyConDataCons, isSynTyCon ) +import VarSet ( intersectVarSet, isEmptyVarSet ) +import PrelNames ( unpackCStringName, unpackCStringUtf8Name ) +import ListSetOps ( equivClasses ) +import List ( nubBy ) \end{code} -\begin{code} -tcTyDecl :: RenamedTyDecl -> TcM s TyCon -\end{code} - -Type synonym decls -~~~~~~~~~~~~~~~~~~ +%************************************************************************ +%* * +\subsection{Type checking} +%* * +%************************************************************************ \begin{code} -tcTyDecl (TySynonym tycon_name tyvar_names rhs src_loc) - = tcAddSrcLoc src_loc $ - tcAddErrCtxt (tySynCtxt tycon_name) $ - - -- Look up the pieces - tcLookupTyCon tycon_name `thenNF_Tc` \ (tycon_kind, rec_tycon) -> - mapAndUnzipNF_Tc tcLookupTyVar tyvar_names `thenNF_Tc` \ (tyvar_kinds, rec_tyvars) -> - - -- Look at the rhs - tcMonoTypeKind rhs `thenTc` \ (rhs_kind, rhs_ty) -> - - -- Unify tycon kind with (k1->...->kn->rhs) - unifyKind tycon_kind - (foldr mkTcArrowKind rhs_kind tyvar_kinds) - `thenTc_` +tcTyDecl :: RecTcEnv -> RenamedTyClDecl -> TcM (Name, TyThingDetails) +tcTyDecl unf_env (TySynonym {tcdName = tycon_name, tcdSynRhs = rhs}) + = tcLookupTyCon tycon_name `thenNF_Tc` \ tycon -> + tcExtendTyVarEnv (tyConTyVars tycon) $ + tcHsType rhs `thenTc` \ rhs_ty -> + returnTc (tycon_name, SynTyDetails rhs_ty) + +tcTyDecl 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 - result_kind, final_tycon_kind :: Kind -- NB not TcKind! - result_kind = getTypeKind rhs_ty - final_tycon_kind = foldr (mkArrowKind . getTyVarKind) result_kind rec_tyvars - - tycon = mkSynTyCon (getItsUnique tycon_name) - (getNameFullName tycon_name) - final_tycon_kind - (length tyvar_names) - rec_tyvars - rhs_ty + tyvars = tyConTyVars tycon in - returnTc tycon -\end{code} - -Algebraic data and newtype decls -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -\begin{code} -tcTyDecl (TyData context tycon_name tyvar_names con_decls derivings pragmas src_loc) - = tcTyDataOrNew DataType context tycon_name tyvar_names con_decls derivings pragmas src_loc - -tcTyDecl (TyNew context tycon_name tyvar_names con_decl derivings pragmas src_loc) - = tcTyDataOrNew NewType context tycon_name tyvar_names con_decl derivings pragmas src_loc - - -tcTyDataOrNew data_or_new context tycon_name tyvar_names con_decls derivings pragmas src_loc - = tcAddSrcLoc src_loc $ - tcAddErrCtxt (tyDataCtxt tycon_name) $ + tcExtendTyVarEnv tyvars $ + tcHsTheta context `thenTc` \ ctxt -> + tcConDecls new_or_data tycon tyvars ctxt con_decls `thenTc` \ data_cons -> + let + sel_ids = mkRecordSelectors unf_env tycon data_cons + in + returnTc (tycon_name, DataTyDetails ctxt data_cons sel_ids) - -- Lookup the pieces - tcLookupTyCon tycon_name `thenNF_Tc` \ (tycon_kind, rec_tycon) -> - mapAndUnzipNF_Tc tcLookupTyVar tyvar_names `thenNF_Tc` \ (tyvar_kinds, rec_tyvars) -> - tc_derivs derivings `thenNF_Tc` \ derived_classes -> +tcTyDecl unf_env (ForeignType {tcdName = tycon_name}) + = returnTc (tycon_name, ForeignTyDetails) - -- Typecheck the context - tcContext context `thenTc` \ ctxt -> - -- Unify tycon kind with (k1->...->kn->Type) - unifyKind tycon_kind - (foldr mkTcArrowKind mkTcTypeKind tyvar_kinds) - `thenTc_` - -- Walk the condecls - mapTc (tcConDecl rec_tycon rec_tyvars ctxt) con_decls - `thenTc` \ con_ids -> - let - -- Construct the tycon - final_tycon_kind :: Kind -- NB not TcKind! - final_tycon_kind = foldr (mkArrowKind . getTyVarKind) mkBoxedTypeKind rec_tyvars - - tycon = mkDataTyCon (getItsUnique tycon_name) - final_tycon_kind - (getNameFullName tycon_name) - rec_tyvars - ctxt - con_ids - derived_classes - ConsVisible -- For now; if constrs are from pragma we are *abstract* - data_or_new - in - returnTc tycon +mkRecordSelectors unf_env tycon data_cons + = -- We'll check later that fields with the same name + -- from different constructors have the same type. + [ mkRecordSelId tycon field unpack_id unpackUtf8_id + | field <- nubBy eq_name fields ] where - tc_derivs Nothing = returnNF_Tc [] - tc_derivs (Just ds) = mapNF_Tc tc_deriv ds + fields = [ field | con <- visibleDataCons data_cons, + field <- dataConFieldLabels con ] + eq_name field1 field2 = fieldLabelName field1 == fieldLabelName field2 - tc_deriv name - = tcLookupClass name `thenNF_Tc` \ (_, clas) -> - returnNF_Tc clas + unpack_id = tcLookupRecId unf_env unpackCStringName + unpackUtf8_id = tcLookupRecId unf_env unpackCStringUtf8Name \end{code} -Constructors -~~~~~~~~~~~~ -\begin{code} -tcConDecl :: TyCon -> [TyVar] -> [(Class,Type)] -> RenamedConDecl -> TcM s Id +%************************************************************************ +%* * +\subsection{Validity check} +%* * +%************************************************************************ -tcConDecl tycon tyvars ctxt (ConDecl name btys src_loc) - = tcAddSrcLoc src_loc $ - let - (stricts, tys) = sep_bangs btys - in - mapTc tcMonoType tys `thenTc` \ arg_tys -> - let - data_con = mkDataCon (getItsUnique name) - (getNameFullName name) - stricts - tyvars - [] -- ToDo: ctxt; limited to tyvars in arg_tys - arg_tys - tycon - -- nullSpecEnv - in - returnTc data_con +checkValidTyCon is called once the mutually-recursive knot has been +tied, so we can look at things freely. -tcConDecl tycon tyvars ctxt (ConOpDecl bty1 op bty2 src_loc) - = tcAddSrcLoc src_loc $ - let - (stricts, tys) = sep_bangs [bty1, bty2] - in - mapTc tcMonoType tys `thenTc` \ arg_tys -> - let - data_con = mkDataCon (getItsUnique op) - (getNameFullName op) - stricts - tyvars - [] -- ToDo: ctxt - arg_tys - tycon - -- nullSpecEnv - in - returnTc data_con +\begin{code} +checkValidTyCon :: TyCon -> TcM () +checkValidTyCon tc + | isSynTyCon tc = checkValidType (TySynCtxt name) syn_rhs + | otherwise + = -- Check the context on the data decl + checkValidTheta (DataTyCtxt name) (tyConTheta tc) `thenTc_` + + -- Check arg types of data constructors + mapTc_ check_data_con data_cons `thenTc_` + + -- Check that fields with the same name share a type + mapTc_ check_fields groups -tcConDecl tycon tyvars ctxt (NewConDecl name ty src_loc) - = tcAddSrcLoc src_loc $ - tcMonoType ty `thenTc` \ arg_ty -> - let - data_con = mkDataCon (getItsUnique name) - (getNameFullName name) - [NotMarkedStrict] - tyvars - [] -- ToDo: ctxt - [arg_ty] - tycon - -- nullSpecEnv - in - returnTc data_con + where + name = tyConName tc + (_, syn_rhs) = getSynTyConDefn tc + data_cons = tyConDataCons tc + + fields = [field | con <- data_cons, field <- dataConFieldLabels con] + groups = equivClasses cmp_name fields + cmp_name field1 field2 = fieldLabelName field1 `compare` fieldLabelName field2 + + check_data_con con = checkValidType (ConArgCtxt (dataConName con)) + (idType (dataConWrapId con)) + -- This checks the argument types and + -- the existential context (if any) + + check_fields 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 +\end{code} -tcConDecl tycon tyvars ctxt (RecConDecl con fields src_loc) - = panic "tcConDecls:RecConDecl" -sep_bangs btys - = unzip (map sep_bang btys) - where - sep_bang (Banged ty) = (MarkedStrict, ty) - sep_bang (Unbanged ty) = (NotMarkedStrict, ty) +%************************************************************************ +%* * +\subsection{Kind and type check constructors} +%* * +%************************************************************************ + +\begin{code} +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. + + +tcConDecls :: NewOrData -> TyCon -> [TyVar] -> ThetaType + -> DataConDetails RenamedConDecl -> TcM (DataConDetails DataCon) + +tcConDecls new_or_data tycon tyvars ctxt con_decls + = case con_decls of + Unknown -> returnTc Unknown + HasCons n -> returnTc (HasCons n) + DataCons cs -> mapTc tc_con_decl cs `thenTc` \ data_cons -> + returnTc (DataCons data_cons) + where + tc_con_decl (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 -> + tcHsTheta 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 ex_tyvars ex_theta btys + = mapTc tcHsType (map getBangType btys) `thenTc` \ arg_tys -> + mk_data_con ex_tyvars ex_theta (map getBangStrictness btys) arg_tys [] + + 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_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 ex_tyvars ex_theta arg_stricts + (map fieldLabelType field_labels) field_labels + + tc_field ((field_label_names, bty), tag) + = tcHsType (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 + arg_tys + 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 + +-- The context for a data constructor should be limited to +-- the type variables mentioned in the arg_tys +thinContext arg_tys ctxt + = filter in_arg_tys ctxt + where + arg_tyvars = tyVarsOfTypes arg_tys + in_arg_tys pred = not $ isEmptyVarSet $ + tyVarsOfPred pred `intersectVarSet` arg_tyvars \end{code} +%************************************************************************ +%* * +\subsection{Errors and contexts} +%* * +%************************************************************************ -Errors and contexts -~~~~~~~~~~~~~~~~~~~ -\begin{code} -tySynCtxt tycon_name sty - = ppCat [ppStr "In the type declaration for", ppr sty tycon_name] -tyDataCtxt tycon_name sty - = ppCat [ppStr "In the data declaration for", ppr sty tycon_name] +\begin{code} +fieldTypeMisMatch field_name + = sep [ptext SLIT("Different constructors give different types for field"), quotes (ppr field_name)] -tyNewCtxt tycon_name sty - = ppCat [ppStr "In the newtype declaration for", ppr sty tycon_name] +exRecConErr name + = ptext SLIT("Can't combine named fields with locally-quantified type variables") + $$ + (ptext SLIT("In the declaration of data constructor") <+> ppr name) \end{code}