X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcTyClsDecls.lhs;h=ffa03fed6e7509b6d60f1d3edc27b72d1184f55c;hb=fb38b8bab2b531ca7ac4ea28ad5b259a00e3759b;hp=ddccb2f11f212aa661bebc2b6a5aff15f2cf6d7d;hpb=275dde6de685153db621b11f2f404aa78d9183e2;p=ghc-hetmet.git diff --git a/compiler/typecheck/TcTyClsDecls.lhs b/compiler/typecheck/TcTyClsDecls.lhs index ddccb2f..ffa03fe 100644 --- a/compiler/typecheck/TcTyClsDecls.lhs +++ b/compiler/typecheck/TcTyClsDecls.lhs @@ -12,12 +12,11 @@ module TcTyClsDecls ( import HsSyn ( TyClDecl(..), HsConDetails(..), HsTyVarBndr(..), ConDecl(..), Sig(..), NewOrData(..), ResType(..), - tyClDeclTyVars, isSynDecl, isClassDecl, isIdxTyDecl, + 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 ) + 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} @@ -212,12 +216,20 @@ 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 +260,15 @@ 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 +277,15 @@ 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 +293,19 @@ 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 @@ -309,18 +327,18 @@ 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 (Just t_typats))) + tycon t_tvs)) k_cons ; 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 - False h98_syntax (Just family) + 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 -- further instance might not introduce a new recursive @@ -329,8 +347,7 @@ tcIdxTyInstDecl1 (decl@TyData {tcdND = new_or_data, tcdLName = L loc tc_name, }) -- construct result - -- !!!TODO: missing eq axiom - ; return (Nothing, Just (ATyCon tycon)) + ; return $ Just (ATyCon tycon) }} where h98_syntax = case cons of -- All constructors have same shape @@ -352,10 +369,8 @@ 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 @@ -616,12 +631,12 @@ 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 - ; return [ATyCon (buildSynTyCon tc_name tvs' (OpenSynTyCon kind))] + ; return [ATyCon $ buildSynTyCon tc_name tvs' (OpenSynTyCon kind)] } -- kind signature for an indexed data type @@ -634,7 +649,7 @@ 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 @@ -679,7 +694,7 @@ tcTyClDecl1 calc_isrec ; tycon <- fixM (\ tycon -> do { data_cons <- mappM (addLocM (tcConDecl unbox_strict new_or_data - tycon final_tvs Nothing)) + tycon final_tvs)) cons ; tc_rhs <- if null cons && is_boot -- In a hs-boot file, empty cons means @@ -708,7 +723,7 @@ tcTyClDecl1 calc_isrec { ctxt' <- tcHsKindedContext ctxt ; fds' <- mappM (addLocM tc_fundep) fundeps ; atss <- mappM (addLocM (tcTyClDecl1 (const Recursive))) ats - ; let ats' = 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 @@ -728,6 +743,19 @@ tcTyClDecl1 calc_isrec ; tvs2' <- mappM tcLookupTyVar tvs2 ; ; return (tvs1', tvs2') } + -- 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}) @@ -737,11 +765,10 @@ tcTyClDecl1 calc_isrec tcConDecl :: Bool -- True <=> -funbox-strict_fields -> NewOrData -> TyCon -> [TyVar] - -> Maybe [Type] -- Just ts <=> type patterns of instance type -> ConDecl Name -> TcM DataCon -tcConDecl unbox_strict NewType tycon tc_tvs mb_typats -- Newtypes +tcConDecl unbox_strict NewType tycon tc_tvs -- Newtypes (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 @@ -751,8 +778,7 @@ tcConDecl unbox_strict NewType tycon tc_tvs mb_typats -- Newtypes tc_tvs [] -- No existentials [] [] -- No equalities, predicates [arg_ty'] - tycon - mb_typats} + tycon } -- Check that a newtype has no existential stuff ; checkTc (null ex_tvs && null (unLoc ex_ctxt)) (newtypeExError name) @@ -765,12 +791,13 @@ tcConDecl unbox_strict NewType tycon tc_tvs mb_typats -- Newtypes -- Check that the constructor has exactly one field } -tcConDecl unbox_strict DataType tycon tc_tvs mb_typats -- Data types +tcConDecl unbox_strict DataType tycon tc_tvs -- Data types (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 @@ -778,8 +805,7 @@ tcConDecl unbox_strict DataType tycon tc_tvs mb_typats -- Data types (argStrictness unbox_strict tycon bangs arg_tys) (map unLoc field_lbls) univ_tvs ex_tvs eq_preds ctxt' arg_tys - data_tc - mb_typats} + data_tc } -- NB: we put data_tc, the type constructor gotten from the -- constructor type signature into the data constructor; -- that way checkValidDataCon can complain if it's wrong. @@ -798,7 +824,7 @@ 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 @@ -818,8 +844,8 @@ 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, @@ -836,7 +862,19 @@ 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] -> [TcType] -> [StrictnessMark] @@ -1157,7 +1195,16 @@ 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"),