X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcTyClsDecls.lhs;h=eee2041d19c624db82b7480629342cf4f989a355;hb=49c98d143c382a1341e1046f5ca00819a25691ba;hp=09349197cf5d7e2412bd482055094c3e77a5ecd4;hpb=feb584b7ffd49827ff2b6e716965cfdcd344570e;p=ghc-hetmet.git diff --git a/compiler/typecheck/TcTyClsDecls.lhs b/compiler/typecheck/TcTyClsDecls.lhs index 0934919..eee2041 100644 --- a/compiler/typecheck/TcTyClsDecls.lhs +++ b/compiler/typecheck/TcTyClsDecls.lhs @@ -11,13 +11,12 @@ module TcTyClsDecls ( #include "HsVersions.h" import HsSyn ( TyClDecl(..), HsConDetails(..), HsTyVarBndr(..), - ConDecl(..), Sig(..), NewOrData(..), ResType(..), - tyClDeclTyVars, isSynDecl, isClassDecl, isIdxTyDecl, + ConDecl(..), HsRecField(..), Sig(..), NewOrData(..), ResType(..), + tyClDeclTyVars, isSynDecl, isIdxTyDecl, isKindSigDecl, hsConArgs, LTyClDecl, tcdName, - hsTyVarName, LHsTyVarBndr, LHsType, HsType(..), - mkHsAppTy + hsTyVarName, LHsTyVarBndr, LHsType ) -import HsTypes ( HsBang(..), getBangStrictness ) +import HsTypes ( HsBang(..), getBangStrictness, hsLTyVarNames ) import BasicTypes ( RecFlag(..), StrictnessMark(..) ) import HscTypes ( implicitTyThings, ModDetails ) import BuildTyCl ( buildClass, buildAlgTyCon, buildSynTyCon, buildDataCon, @@ -25,8 +24,9 @@ import BuildTyCl ( buildClass, buildAlgTyCon, buildSynTyCon, buildDataCon, import TcRnMonad import TcEnv ( TyThing(..), tcLookupLocated, tcLookupLocatedGlobal, - tcExtendGlobalEnv, tcExtendKindEnv, tcExtendKindEnvTvs, - tcExtendRecEnv, tcLookupTyVar, InstInfo ) + tcExtendGlobalEnv, tcExtendKindEnv, + tcExtendKindEnvTvs, newFamInstTyConName, + tcExtendRecEnv, tcLookupTyVar, tcLookupLocatedTyCon ) import TcTyDecls ( calcRecFlags, calcClassCycles, calcSynCycles ) import TcClassDcl ( tcClassSigs, tcAddDeclCtxt ) import TcHsType ( kcHsTyVars, kcHsLiftedSigType, kcHsType, @@ -37,10 +37,11 @@ import TcMType ( newKindVar, checkValidTheta, checkValidType, -- checkFreeness, UserTypeCtxt(..), SourceTyCtxt(..) ) import TcType ( TcKind, TcType, Type, tyVarsOfType, mkPhiTy, - mkArrowKind, liftedTypeKind, mkTyVarTys, - tcSplitSigmaTy, tcEqTypes, tcGetTyVar_maybe ) -import Type ( PredType(..), splitTyConApp_maybe, mkTyVarTy, - newTyConInstRhs, isLiftedTypeKind, Kind + mkArrowKind, liftedTypeKind, + tcSplitSigmaTy, tcGetTyVar_maybe ) +import Type ( splitTyConApp_maybe, + newTyConInstRhs, isLiftedTypeKind, Kind, + splitKindFunTys, mkArrowKinds -- pprParendType, pprThetaArrow ) import Generics ( validGenericMethodType, canDoGenerics ) @@ -49,27 +50,30 @@ import TyCon ( TyCon, AlgTyConRhs( AbstractTyCon, OpenDataTyCon, OpenNewTyCon ), SynTyConRhs( OpenSynTyCon, SynonymTyCon ), tyConDataCons, mkForeignTyCon, isProductTyCon, - isRecursiveTyCon, isOpenTyCon, + isRecursiveTyCon, tyConStupidTheta, synTyConRhs, isSynTyCon, tyConName, - isNewTyCon, tyConKind, makeTyConAssoc, isAssocTyCon ) + isNewTyCon, isDataTyCon, tyConKind, + setTyConArgPoss ) import DataCon ( DataCon, dataConUserType, dataConName, dataConFieldLabels, dataConTyCon, dataConAllTyVars, dataConFieldType, dataConResTys ) -import Var ( TyVar, idType, idName ) +import Var ( TyVar, idType, idName, tyVarName, setTyVarName ) import VarSet ( elemVarSet, mkVarSet ) -import Name ( Name, getSrcLoc ) +import Name ( Name, getSrcLoc, tidyNameOcc, getOccName ) +import OccName ( initTidyOccEnv, tidyOccName ) import Outputable -import Maybe ( isJust, fromJust, isNothing ) +import Maybe ( isJust, fromJust, isNothing, catMaybes ) import Maybes ( expectJust ) +import Monad ( unless ) import Unify ( tcMatchTys, tcMatchTyX ) -import Util ( zipLazy, isSingleton, notNull, sortLe ) -import List ( partition ) -import SrcLoc ( Located(..), unLoc, getLoc, srcLocSpan ) +import Util ( zipLazy, isSingleton, notNull, sortLe, mapAccumL ) +import List ( partition, elemIndex ) +import SrcLoc ( Located(..), unLoc, getLoc, srcLocSpan, + srcSpanStart ) import ListSetOps ( equivClasses, minusList ) -import List ( delete ) import Digraph ( SCC(..) ) import DynFlags ( DynFlag( Opt_GlasgowExts, Opt_Generics, - Opt_UnboxStrictFields ) ) + Opt_UnboxStrictFields, Opt_IndexedTypes ) ) \end{code} @@ -192,6 +196,7 @@ tcTyAndClassDecls boot_details allDecls ; let { -- Calculate rec-flag ; calc_rec = calcRecFlags boot_details rec_alg_tyclss ; tc_decl = addLocM (tcTyClDecl calc_rec) } + -- Type-check the type synonyms, and extend the envt ; syn_tycons <- tcSynDecls kc_syn_decls ; tcExtendGlobalEnv syn_tycons $ do @@ -212,12 +217,20 @@ tcTyAndClassDecls boot_details allDecls -- Add the implicit things; -- we want them in the environment because -- they may be mentioned in interface files + -- NB: All associated types and their implicit things will be added a + -- second time here. This doesn't matter as the definitions are + -- the same. ; let { implicit_things = concatMap implicitTyThings alg_tyclss } ; traceTc ((text "Adding" <+> ppr alg_tyclss) $$ (text "and" <+> ppr implicit_things)) ; tcExtendGlobalEnv implicit_things getGblEnv }} where + -- Pull associated types out of class declarations, to tie them into the + -- knot above. + -- NB: We put them in the same place in the list as `tcTyClDecl' will + -- eventually put the matching `TyThing's. That's crucial; otherwise, + -- the two argument lists of `mkGlobalThings' don't match up. addATs decl@(L _ (ClassDecl {tcdATs = ats})) = decl : ats addATs decl = [decl] @@ -248,16 +261,15 @@ they share a lot of kinding and type checking code with ordinary algebraic data types (and GADTs). \begin{code} -tcIdxTyInstDecl :: LTyClDecl Name - -> TcM (Maybe InstInfo, Maybe TyThing) -- Nothing if error +tcIdxTyInstDecl :: LTyClDecl Name -> TcM (Maybe TyThing) -- Nothing if error tcIdxTyInstDecl (L loc decl) = -- Prime error recovery, set source location - recoverM (returnM (Nothing, Nothing)) $ + recoverM (returnM Nothing) $ setSrcSpan loc $ tcAddDeclCtxt decl $ - do { -- indexed data types require -fglasgow-exts and can't be in an + do { -- indexed data types require -findexed-types and can't be in an -- hs-boot file - ; gla_exts <- doptM Opt_GlasgowExts + ; gla_exts <- doptM Opt_IndexedTypes ; is_boot <- tcIsHsBoot -- Are we compiling an hs-boot file? ; checkTc gla_exts $ badIdxTyDecl (tcdLName decl) ; checkTc (not is_boot) $ badBootTyIdxDeclErr @@ -266,12 +278,15 @@ tcIdxTyInstDecl (L loc decl) ; tcIdxTyInstDecl1 decl } -tcIdxTyInstDecl1 :: TyClDecl Name - -> TcM (Maybe InstInfo, Maybe TyThing) -- Nothing if error +tcIdxTyInstDecl1 :: TyClDecl Name -> TcM (Maybe TyThing) -- Nothing if error tcIdxTyInstDecl1 (decl@TySynonym {}) - = kcIdxTyPats decl $ \k_tvs k_typats resKind _ -> - do { -- (1) kind check the right hand side of the type equation + = kcIdxTyPats decl $ \k_tvs k_typats resKind family -> + do { -- check that the family declaration is for a synonym + unless (isSynTyCon family) $ + addErr (wrongKindOfFamily family) + + ; -- (1) kind check the right hand side of the type equation ; k_rhs <- kcCheckHsType (tcdSynRhs decl) resKind -- (2) type check type equation @@ -279,15 +294,19 @@ tcIdxTyInstDecl1 (decl@TySynonym {}) ; t_typats <- mappM tcHsKindedType k_typats ; t_rhs <- tcHsKindedType k_rhs - -- construct type rewrite rule -- !!!of the form: forall t_tvs. (tcdLName decl) t_typats = t_rhs - ; return (Nothing, Nothing) -- !!!TODO: need InstInfo for eq axioms + ; return Nothing -- !!!TODO: need TyThing for indexed synonym }} tcIdxTyInstDecl1 (decl@TyData {tcdND = new_or_data, tcdLName = L loc tc_name, tcdCons = cons}) = kcIdxTyPats decl $ \k_tvs k_typats resKind family -> - do { -- (1) kind check the data declaration as usual + do { -- check that the family declaration is for the right kind + unless (new_or_data == NewType && isNewTyCon family || + new_or_data == DataType && isDataTyCon family) $ + addErr (wrongKindOfFamily family) + + ; -- (1) kind check the data declaration as usual ; k_decl <- kcDataDecl decl k_tvs ; let k_ctxt = tcdCtxt k_decl k_cons = tcdCons k_decl @@ -309,6 +328,7 @@ tcIdxTyInstDecl1 (decl@TyData {tcdND = new_or_data, tcdLName = L loc tc_name, ; t_typats <- mappM tcHsKindedType k_typats ; stupid_theta <- tcHsKindedContext k_ctxt + ; rep_tc_name <- newFamInstTyConName tc_name (srcSpanStart loc) ; tycon <- fixM (\ tycon -> do { data_cons <- mappM (addLocM (tcConDecl unbox_strict new_or_data tycon t_tvs)) @@ -316,10 +336,9 @@ tcIdxTyInstDecl1 (decl@TyData {tcdND = new_or_data, tcdLName = L loc tc_name, ; tc_rhs <- case new_or_data of DataType -> return (mkDataTyConRhs data_cons) - NewType -> - ASSERT( isSingleton data_cons ) - mkNewTyConRhs tc_name tycon (head data_cons) - ; buildAlgTyCon tc_name t_tvs stupid_theta tc_rhs Recursive + NewType -> ASSERT( isSingleton data_cons ) + mkNewTyConRhs tc_name tycon (head data_cons) + ; buildAlgTyCon rep_tc_name t_tvs stupid_theta tc_rhs Recursive False h98_syntax (Just (family, t_typats)) -- We always assume that indexed types are recursive. Why? -- (1) Due to their open nature, we can never be sure that a @@ -329,7 +348,7 @@ tcIdxTyInstDecl1 (decl@TyData {tcdND = new_or_data, tcdLName = L loc tc_name, }) -- construct result - ; return (Nothing, Just (ATyCon tycon)) + ; return $ Just (ATyCon tycon) }} where h98_syntax = case cons of -- All constructors have same shape @@ -351,10 +370,8 @@ kcIdxTyPats :: TyClDecl Name -> TcM a kcIdxTyPats decl thing_inside = kcHsTyVars (tcdTyVars decl) $ \tvs -> - do { tc_ty_thing <- tcLookupLocated (tcdLName decl) - ; let { family = case tc_ty_thing of - AGlobal (ATyCon family) -> family - ; (kinds, resKind) = splitKindFunTys (tyConKind family) + do { family <- tcLookupLocatedTyCon (tcdLName decl) + ; let { (kinds, resKind) = splitKindFunTys (tyConKind family) ; hs_typats = fromJust $ tcdTyPats decl } -- we may not have more parameters than the kind indicates @@ -556,14 +573,15 @@ kcDataDecl decl@(TyData {tcdND = new_or_data, tcdCtxt = ctxt, tcdCons = cons}) ; cons' <- mappM (wrapLocM kc_con_decl) cons ; return (decl {tcdTyVars = tvs, tcdCtxt = ctxt', tcdCons = cons'}) } where - kc_con_decl (ConDecl name expl ex_tvs ex_ctxt details res) = do + -- doc comments are typechecked to Nothing here + kc_con_decl (ConDecl name expl ex_tvs ex_ctxt details res _) = do kcHsTyVars ex_tvs $ \ex_tvs' -> do ex_ctxt' <- kcHsContext ex_ctxt details' <- kc_con_details details res' <- case res of ResTyH98 -> return ResTyH98 ResTyGADT ty -> do { ty' <- kcHsSigType ty; return (ResTyGADT ty') } - return (ConDecl name expl ex_tvs' ex_ctxt' details' res') + return (ConDecl name expl ex_tvs' ex_ctxt' details' res' Nothing) kc_con_details (PrefixCon btys) = do { btys' <- mappM kc_larg_ty btys ; return (PrefixCon btys') } @@ -572,7 +590,7 @@ kcDataDecl decl@(TyData {tcdND = new_or_data, tcdCtxt = ctxt, tcdCons = cons}) kc_con_details (RecCon fields) = do { fields' <- mappM kc_field fields; return (RecCon fields') } - kc_field (fld, bty) = do { bty' <- kc_larg_ty bty ; return (fld, bty') } + kc_field (HsRecField fld bty d) = do { bty' <- kc_larg_ty bty ; return (HsRecField fld bty' d) } kc_larg_ty bty = case new_or_data of DataType -> kcHsSigType bty @@ -615,7 +633,7 @@ tcTyClDecl1 _calc_isrec (TyFunction {tcdLName = L _ tc_name, tcdTyVars = tvs, tcdKind = kind}) = tcTyVarBndrs tvs $ \ tvs' -> do { traceTc (text "type family: " <+> ppr tc_name) - ; gla_exts <- doptM Opt_GlasgowExts + ; gla_exts <- doptM Opt_IndexedTypes -- Check that we don't use kind signatures without Glasgow extensions ; checkTc gla_exts $ badSigTyDecl tc_name @@ -633,7 +651,7 @@ tcTyClDecl1 _calc_isrec ; let final_tvs = tvs' ++ extra_tvs -- we may not need these ; checkTc (null . unLoc $ ctxt) $ badKindSigCtxt tc_name - ; gla_exts <- doptM Opt_GlasgowExts + ; gla_exts <- doptM Opt_IndexedTypes -- Check that we don't use kind signatures without Glasgow extensions ; checkTc gla_exts $ badSigTyDecl tc_name @@ -707,7 +725,7 @@ tcTyClDecl1 calc_isrec { ctxt' <- tcHsKindedContext ctxt ; fds' <- mappM (addLocM tc_fundep) fundeps ; atss <- mappM (addLocM (tcTyClDecl1 (const Recursive))) ats - ; let ats' = map makeTyThingAssoc . concat $ atss + ; let ats' = zipWith setTyThingPoss atss (map (tcdTyVars . unLoc) ats) ; sig_stuff <- tcClassSigs class_name sigs meths ; clas <- fixM (\ clas -> let -- This little knot is just so we can get @@ -726,9 +744,20 @@ tcTyClDecl1 calc_isrec tc_fundep (tvs1, tvs2) = do { tvs1' <- mappM tcLookupTyVar tvs1 ; ; tvs2' <- mappM tcLookupTyVar tvs2 ; ; return (tvs1', tvs2') } - makeTyThingAssoc (ATyCon tycon) = ATyCon (makeTyConAssoc tycon) - makeTyThingAssoc _ = panic "makeTyThingAssoc" + -- For each AT argument compute the position of the corresponding class + -- parameter in the class head. This will later serve as a permutation + -- vector when checking the validity of instance declarations. + setTyThingPoss [ATyCon tycon] atTyVars = + let classTyVars = hsLTyVarNames tvs + poss = catMaybes + . map (`elemIndex` classTyVars) + . hsLTyVarNames + $ atTyVars + -- There will be no Nothing, as we already passed renaming + in + ATyCon (setTyConArgPoss tycon poss) + setTyThingPoss _ _ = panic "TcTyClsDecls.setTyThingPoss" tcTyClDecl1 calc_isrec (ForeignType {tcdLName = L _ tc_name, tcdExtName = tc_ext_name}) @@ -742,7 +771,7 @@ tcConDecl :: Bool -- True <=> -funbox-strict_fields -> TcM DataCon tcConDecl unbox_strict NewType tycon tc_tvs -- Newtypes - (ConDecl name _ ex_tvs ex_ctxt details ResTyH98) + (ConDecl name _ ex_tvs ex_ctxt details ResTyH98 _) = do { let tc_datacon field_lbls arg_ty = do { arg_ty' <- tcHsKindedType arg_ty -- No bang on newtype ; buildDataCon (unLoc name) False {- Prefix -} @@ -758,23 +787,24 @@ tcConDecl unbox_strict NewType tycon tc_tvs -- Newtypes ; case details of PrefixCon [arg_ty] -> tc_datacon [] arg_ty - RecCon [(field_lbl, arg_ty)] -> tc_datacon [field_lbl] arg_ty + RecCon [HsRecField field_lbl arg_ty _] -> tc_datacon [field_lbl] arg_ty other -> failWithTc (newtypeFieldErr name (length (hsConArgs details))) -- Check that the constructor has exactly one field } tcConDecl unbox_strict DataType tycon tc_tvs -- Data types - (ConDecl name _ tvs ctxt details res_ty) + (ConDecl name _ tvs ctxt details res_ty _) = tcTyVarBndrs tvs $ \ tvs' -> do { ctxt' <- tcHsKindedContext ctxt ; (univ_tvs, ex_tvs, eq_preds, data_tc) <- tcResultType tycon tc_tvs tvs' res_ty ; let + -- Tiresome: tidy the tyvar binders, since tc_tvs and tvs' may have the same OccNames tc_datacon is_infix field_lbls btys = do { let bangs = map getBangStrictness btys ; arg_tys <- mappM tcHsBangType btys ; buildDataCon (unLoc name) is_infix - (argStrictness unbox_strict tycon bangs arg_tys) + (argStrictness unbox_strict bangs arg_tys) (map unLoc field_lbls) univ_tvs ex_tvs eq_preds ctxt' arg_tys data_tc } @@ -787,7 +817,7 @@ tcConDecl unbox_strict DataType tycon tc_tvs -- Data types InfixCon bty1 bty2 -> tc_datacon True [] [bty1,bty2] RecCon fields -> tc_datacon False field_names btys where - (field_names, btys) = unzip fields + (field_names, btys) = unzip [ (n, t) | HsRecField n t _ <- fields ] } @@ -796,7 +826,7 @@ tcResultType :: TyCon -> [TyVar] -- where MkT :: forall a b c. ... -> ResType Name -> TcM ([TyVar], -- Universal - [TyVar], -- Existential + [TyVar], -- Existential (distinct OccNames from univs) [(TyVar,Type)], -- Equality predicates TyCon) -- TyCon given in the ResTy -- We don't check that the TyCon given in the ResTy is @@ -816,8 +846,8 @@ tcResultType _ tc_tvs dc_tvs (ResTyGADT res_ty) -- ([a,z,c], [x,y], [a:=:(x,y), c:=:z], T) = do { (dc_tycon, res_tys) <- tcLHsConResTy res_ty - -- NB: tc_tvs and dc_tvs are distinct - ; let univ_tvs = choose_univs [] tc_tvs res_tys + + ; let univ_tvs = choose_univs [] tidy_tc_tvs res_tys -- Each univ_tv is either a dc_tv or a tc_tv ex_tvs = dc_tvs `minusList` univ_tvs eq_spec = [ (tv, ty) | (tv,ty) <- univ_tvs `zip` res_tys, @@ -834,13 +864,25 @@ tcResultType _ tc_tvs dc_tvs (ResTyGADT res_ty) | otherwise = tc_tv : choose_univs used tc_tvs res_tys -------------------- + -- NB: tc_tvs and dc_tvs are distinct, but + -- we want them to be *visibly* distinct, both for + -- interface files and general confusion. So rename + -- the tc_tvs, since they are not used yet (no + -- consequential renaming needed) + init_occ_env = initTidyOccEnv (map getOccName dc_tvs) + (_, tidy_tc_tvs) = mapAccumL tidy_one init_occ_env tc_tvs + tidy_one env tv = (env', setTyVarName tv (tidyNameOcc name occ')) + where + name = tyVarName tv + (env', occ') = tidyOccName env (getOccName name) + + ------------------- argStrictness :: Bool -- True <=> -funbox-strict_fields - -> TyCon -> [HsBang] + -> [HsBang] -> [TcType] -> [StrictnessMark] -argStrictness unbox_strict tycon bangs arg_tys +argStrictness unbox_strict bangs arg_tys = ASSERT( length bangs == length arg_tys ) - zipWith (chooseBoxingStrategy unbox_strict tycon) arg_tys bangs + zipWith (chooseBoxingStrategy unbox_strict) arg_tys bangs -- We attempt to unbox/unpack a strict field when either: -- (i) The field is marked '!!', or @@ -848,8 +890,8 @@ argStrictness unbox_strict tycon bangs arg_tys -- -- We have turned off unboxing of newtypes because coercions make unboxing -- and reboxing more complicated -chooseBoxingStrategy :: Bool -> TyCon -> TcType -> HsBang -> StrictnessMark -chooseBoxingStrategy unbox_strict_fields tycon arg_ty bang +chooseBoxingStrategy :: Bool -> TcType -> HsBang -> StrictnessMark +chooseBoxingStrategy unbox_strict_fields arg_ty bang = case bang of HsNoBang -> NotMarkedStrict HsStrict | unbox_strict_fields @@ -862,13 +904,21 @@ chooseBoxingStrategy unbox_strict_fields tycon arg_ty bang can_unbox arg_ty = case splitTyConApp_maybe arg_ty of Nothing -> False Just (arg_tycon, tycon_args) -> - not (isRecursiveTyCon tycon) && + not (isRecursiveTyCon arg_tycon) && -- Note [Recusive unboxing] isProductTyCon arg_tycon && (if isNewTyCon arg_tycon then can_unbox (newTyConInstRhs arg_tycon tycon_args) else True) \end{code} +Note [Recursive unboxing] +~~~~~~~~~~~~~~~~~~~~~~~~~ +Be careful not to try to unbox this! + data T = MkT !T Int +But it's the *argument* type that matters. This is fine: + data S = MkS S !Int +because Int is non-recursive. + %************************************************************************ %* * \subsection{Dependency analysis} @@ -1155,7 +1205,16 @@ tooFewParmsErr tc_name = ptext SLIT("Indexed type instance has too few parameters:") <+> quotes (ppr tc_name) -badBootTyIdxDeclErr = ptext SLIT("Illegal indexed type instance in hs-boot file") +badBootTyIdxDeclErr = + ptext SLIT("Illegal indexed type instance in hs-boot file") + +wrongKindOfFamily family = + ptext SLIT("Wrong category of type instance; declaration was for a") <+> + kindOfFamily + where + kindOfFamily | isSynTyCon family = ptext SLIT("type synonym") + | isDataTyCon family = ptext SLIT("data type") + | isNewTyCon family = ptext SLIT("newtype") emptyConDeclsErr tycon = sep [quotes (ppr tycon) <+> ptext SLIT("has no constructors"),