X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcClassDcl.lhs;h=14682a295dfce033d00222e85b745e880a692a1b;hb=28a464a75e14cece5db40f2765a29348273ff2d2;hp=b24701dacb897642e412efa7e5ec27fc743767ae;hpb=af5a215172aa3b964ece212f229bfee9f7c6b6b2;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcClassDcl.lhs b/ghc/compiler/typecheck/TcClassDcl.lhs index b24701d..14682a2 100644 --- a/ghc/compiler/typecheck/TcClassDcl.lhs +++ b/ghc/compiler/typecheck/TcClassDcl.lhs @@ -13,24 +13,24 @@ module TcClassDcl ( tcClassSigs, tcClassDecl2, #include "HsVersions.h" import HsSyn -import BasicTypes ( RecFlag(..) ) import RnHsSyn ( maybeGenericMatch, extractHsTyVars ) import RnExpr ( rnLExpr ) import RnEnv ( lookupTopBndrRn, lookupImportedName ) - -import Inst ( Inst, InstOrigin(..), instToId, newDicts, newMethod ) -import TcEnv ( tcLookupLocatedClass, tcExtendLocalValEnv2, - tcExtendTyVarEnv2, +import Inst ( instToId, newDicts, newDictsAtLoc, newMethod, getOverlapFlag ) +import InstEnv ( mkLocalInstance ) +import TcEnv ( tcLookupLocatedClass, + tcExtendTyVarEnv, tcExtendIdEnv, InstInfo(..), pprInstInfoDetails, simpleInstInfoTyCon, simpleInstInfoTy, InstBindings(..), newDFunName ) -import TcBinds ( tcMonoBinds, tcSpecSigs ) -import TcHsType ( TcSigInfo(..), mkTcSig, tcHsKindedType, tcHsSigType ) -import TcSimplify ( tcSimplifyCheck, bindInstsOfLocalFuns ) +import TcBinds ( TcPragFun, tcMonoBinds, tcPrags, mkPragFun, TcSigInfo(..) ) +import TcHsType ( tcHsKindedType, tcHsSigType ) +import TcSimplify ( tcSimplifyCheck ) import TcUnify ( checkSigTyVars, sigCtxt ) -import TcMType ( tcInstTyVars, UserTypeCtxt( GenPatCtxt ) ) -import TcType ( Type, TyVarDetails(..), TcType, TcThetaType, TcTyVar, +import TcMType ( tcSkolSigTyVars ) +import TcType ( Type, SkolemInfo(ClsSkol, InstSkol), UserTypeCtxt( GenPatCtxt ), + TcType, TcThetaType, TcTyVar, mkTyVarTys, mkClassPred, tcSplitSigmaTy, tcSplitFunTys, tcIsTyVarTy, tcSplitTyConApp_maybe, tcSplitForAllTys, tcSplitPhiTy, getClassPredTys_maybe, mkPhiTy, mkTyVarTy @@ -41,19 +41,17 @@ import PrelInfo ( nO_METHOD_BINDING_ERROR_ID ) import Class ( classTyVars, classBigSig, Class, ClassOpItem, DefMeth (..) ) import TyCon ( TyCon, tyConName, tyConHasGenerics ) -import Subst ( substTyWith ) +import Type ( substTyWith ) import MkId ( mkDefaultMethodId, mkDictFunId ) -import Id ( Id, idType, idName, mkUserLocal, setInlinePragma ) +import Id ( Id, idType, idName, mkUserLocal ) import Name ( Name, NamedThing(..) ) import NameEnv ( NameEnv, lookupNameEnv, mkNameEnv ) -import NameSet ( emptyNameSet, unitNameSet, nameSetToList ) +import NameSet ( nameSetToList ) import OccName ( reportIfUnused, mkDefaultMethodOcc ) import RdrName ( RdrName, mkDerivedRdrName ) import Outputable -import Var ( TyVar ) import PrelNames ( genericTyConNames ) -import CmdLineOpts -import UnicodeUtil ( stringToUtf8 ) +import DynFlags import ErrUtils ( dumpIfSet_dyn ) import Util ( count, lengthIs, isSingleton, lengthExceeds ) import Unique ( Uniquable(..) ) @@ -61,6 +59,7 @@ import ListSetOps ( equivClassesByUniq, minusList ) import SrcLoc ( Located(..), srcSpanStart, unLoc, noLoc ) import Maybes ( seqMaybe, isJust, mapCatMaybes ) import List ( partition ) +import BasicTypes ( RecFlag(..), Boxity(..) ) import Bag import FastString \end{code} @@ -118,8 +117,8 @@ tcClassSigs clas sigs def_methods = do { dm_env <- checkDefaultBinds clas op_names def_methods ; mappM (tcClassSig dm_env) op_sigs } where - op_sigs = [sig | sig@(L _ (Sig _ _)) <- sigs] - op_names = [n | sig@(L _ (Sig (L _ n) _)) <- op_sigs] + op_sigs = [sig | sig@(L _ (TypeSig _ _)) <- sigs] + op_names = [n | sig@(L _ (TypeSig (L _ n) _)) <- op_sigs] checkDefaultBinds :: Name -> [Name] -> LHsBinds Name -> TcM (NameEnv Bool) @@ -132,7 +131,7 @@ checkDefaultBinds clas ops binds = do dm_infos <- mapM (addLocM (checkDefaultBind clas ops)) (bagToList binds) return (mkNameEnv dm_infos) -checkDefaultBind clas ops (FunBind (L _ op) _ matches) +checkDefaultBind clas ops (FunBind {fun_id = L _ op, fun_matches = MatchGroup matches _ }) = do { -- Check that the op is from this class checkTc (op `elem` ops) (badMethodErr clas op) @@ -151,8 +150,8 @@ tcClassSig :: NameEnv Bool -- Info about default methods; -> LSig Name -> TcM TcMethInfo -tcClassSig dm_env (L loc (Sig (L _ op_name) op_hs_ty)) - = addSrcSpan loc $ do +tcClassSig dm_env (L loc (TypeSig (L _ op_name) op_hs_ty)) + = setSrcSpan loc $ do { op_ty <- tcHsKindedType op_hs_ty -- Class tyvars already in scope ; let dm = case lookupNameEnv dm_env op_name of Nothing -> NoDefMeth @@ -232,8 +231,8 @@ tcClassDecl2 :: LTyClDecl Name -- The class declaration tcClassDecl2 (L loc (ClassDecl {tcdLName = class_name, tcdSigs = sigs, tcdMeths = default_binds})) - = recoverM (returnM (emptyBag, [])) $ - addSrcSpan loc $ + = recoverM (returnM (emptyLHsBinds, [])) $ + setSrcSpan loc $ tcLookupLocatedClass class_name `thenM` \ clas -> -- We make a separate binding for each default method. @@ -246,8 +245,8 @@ tcClassDecl2 (L loc (ClassDecl {tcdLName = class_name, tcdSigs = sigs, -- default methods. Better to make separate AbsBinds for each let (tyvars, _, _, op_items) = classBigSig clas - prags = filter (isPragSig.unLoc) sigs - tc_dm = tcDefMeth clas tyvars default_binds prags + prag_fn = mkPragFun sigs + tc_dm = tcDefMeth clas tyvars default_binds prag_fn dm_sel_ids = [sel_id | (sel_id, DefMeth) <- op_items] -- Generate code for polymorphic default methods only @@ -260,44 +259,47 @@ tcClassDecl2 (L loc (ClassDecl {tcdLName = class_name, tcdSigs = sigs, mapAndUnzipM tc_dm dm_sel_ids `thenM` \ (defm_binds, dm_ids_s) -> returnM (listToBag defm_binds, concat dm_ids_s) -tcDefMeth clas tyvars binds_in prags sel_id - = lookupTopBndrRn (mkDefMethRdrName sel_id) `thenM` \ dm_name -> - tcInstTyVars ClsTv tyvars `thenM` \ (clas_tyvars, inst_tys, _) -> - let - dm_ty = idType sel_id -- Same as dict selector! - theta = [mkClassPred clas inst_tys] - local_dm_id = mkDefaultMethodId dm_name dm_ty - xtve = tyvars `zip` clas_tyvars - origin = ClassDeclOrigin - in - mkMethodBind origin clas inst_tys - binds_in (sel_id, DefMeth) `thenM` \ (_, meth_info) -> - newDicts origin theta `thenM` \ [this_dict] -> - getLIE (tcMethodBind xtve clas_tyvars theta - [this_dict] prags meth_info) `thenM` \ (defm_bind, insts_needed) -> +tcDefMeth clas tyvars binds_in prag_fn sel_id + = do { dm_name <- lookupTopBndrRn (mkDefMethRdrName sel_id) + ; let rigid_info = ClsSkol clas + clas_tyvars = tcSkolSigTyVars rigid_info tyvars + inst_tys = mkTyVarTys clas_tyvars + dm_ty = idType sel_id -- Same as dict selector! + theta = [mkClassPred clas inst_tys] + local_dm_id = mkDefaultMethodId dm_name dm_ty + origin = SigOrigin rigid_info + + ; (_, meth_info) <- mkMethodBind origin clas inst_tys binds_in (sel_id, DefMeth) + ; [this_dict] <- newDicts origin theta + ; (defm_bind, insts_needed) <- getLIE (tcMethodBind clas_tyvars theta + [this_dict] prag_fn meth_info) - addErrCtxt (defltMethCtxt clas) $ + ; addErrCtxt (defltMethCtxt clas) $ do -- Check the context - tcSimplifyCheck - (ptext SLIT("class") <+> ppr clas) - clas_tyvars - [this_dict] - insts_needed `thenM` \ dict_binds -> + { dict_binds <- tcSimplifyCheck + (ptext SLIT("class") <+> ppr clas) + clas_tyvars + [this_dict] + insts_needed -- Simplification can do unification - checkSigTyVars clas_tyvars `thenM` \ clas_tyvars' -> + ; checkSigTyVars clas_tyvars - let - (_,dm_inst_id,_) = meth_info - full_bind = AbsBinds - clas_tyvars' - [instToId this_dict] - [(clas_tyvars', local_dm_id, dm_inst_id)] - emptyNameSet -- No inlines (yet) - (dict_binds `unionBags` defm_bind) - in - returnM (noLoc full_bind, [local_dm_id]) + -- Inline pragmas + -- We'll have an inline pragma on the local binding, made by tcMethodBind + -- but that's not enough; we want one on the global default method too + -- Specialisations, on the other hand, belong on the thing inside only, I think + ; let (_,dm_inst_id,_) = meth_info + sel_name = idName sel_id + inline_prags = filter isInlineLSig (prag_fn sel_name) + ; prags <- tcPrags dm_inst_id inline_prags + + ; let full_bind = AbsBinds clas_tyvars + [instToId this_dict] + [(clas_tyvars, local_dm_id, dm_inst_id, prags)] + (dict_binds `unionBags` defm_bind) + ; returnM (noLoc full_bind, [local_dm_id]) }} mkDefMethRdrName :: Id -> RdrName mkDefMethRdrName sel_id = mkDerivedRdrName (idName sel_id) mkDefaultMethodOcc @@ -321,22 +323,22 @@ type MethodSpec = (Id, -- Global selector Id LHsBind Name) -- Binding for the method tcMethodBind - :: [(TyVar,TcTyVar)] -- Bindings for type environment - -> [TcTyVar] -- Instantiated type variables for the + :: [TcTyVar] -- Skolemised type variables for the -- enclosing class/instance decl. -- They'll be signature tyvars, and we -- want to check that they don't get bound + -- Also they are scoped, so we bring them into scope -- Always equal the range of the type envt -> TcThetaType -- Available theta; it's just used for the error message -> [Inst] -- Available from context, used to simplify constraints -- from the method body - -> [LSig Name] -- Pragmas (e.g. inline pragmas) + -> TcPragFun -- Pragmas (e.g. inline pragmas) -> MethodSpec -- Details of this method -> TcM (LHsBinds Id) -tcMethodBind xtve inst_tyvars inst_theta avail_insts prags +tcMethodBind inst_tyvars inst_theta avail_insts prag_fn (sel_id, meth_id, meth_bind) - = recoverM (returnM emptyBag) $ + = recoverM (returnM emptyLHsBinds) $ -- If anything fails, recover returning no bindings. -- This is particularly useful when checking the default-method binding of -- a class decl. If we don't recover, we don't add the default method to @@ -344,13 +346,20 @@ tcMethodBind xtve inst_tyvars inst_theta avail_insts prags -- Check the bindings; first adding inst_tyvars to the envt -- so that we don't quantify over them in nested places - mkTcSig meth_id `thenM` \ meth_sig -> - tcExtendTyVarEnv2 xtve ( - addErrCtxt (methodCtxt sel_id) $ - getLIE $ - tcMonoBinds (unitBag meth_bind) [meth_sig] NonRecursive - ) `thenM` \ ((meth_bind,_), meth_lie) -> + + let meth_sig = noLoc (TypeSig (noLoc (idName meth_id)) (noLoc bogus_ty)) + bogus_ty = HsTupleTy Boxed [] -- *Only* used to extract scoped type + -- variables... and there aren't any + lookup_sig name = ASSERT( name == idName meth_id ) + Just meth_sig + in + tcExtendTyVarEnv inst_tyvars ( + tcExtendIdEnv [meth_id] $ -- In scope for tcInstSig + addErrCtxt (methodCtxt sel_id) $ + getLIE $ + tcMonoBinds [meth_bind] lookup_sig Recursive + ) `thenM` \ ((meth_bind, mono_bind_infos), meth_lie) -> -- Now do context reduction. We simplify wrt both the local tyvars -- and the ones of the class/instance decl, so that there is @@ -360,59 +369,32 @@ tcMethodBind xtve inst_tyvars inst_theta avail_insts prags -- -- We do this for each method independently to localise error messages - let - TySigInfo { sig_poly_id = meth_id, sig_tvs = meth_tvs, - sig_theta = meth_theta, sig_mono_id = local_meth_id } = meth_sig - in - addErrCtxtM (sigCtxt sel_id inst_tyvars inst_theta (idType meth_id)) $ - newDicts SignatureOrigin meth_theta `thenM` \ meth_dicts -> - let + let + [(_, Just sig, local_meth_id)] = mono_bind_infos + in + + addErrCtxtM (sigCtxt sel_id inst_tyvars inst_theta (idType meth_id)) $ + newDictsAtLoc (sig_loc sig) (sig_theta sig) `thenM` \ meth_dicts -> + let + meth_tvs = sig_tvs sig all_tyvars = meth_tvs ++ inst_tyvars all_insts = avail_insts ++ meth_dicts - in - tcSimplifyCheck + sel_name = idName sel_id + in + tcSimplifyCheck (ptext SLIT("class or instance method") <+> quotes (ppr sel_id)) all_tyvars all_insts meth_lie `thenM` \ lie_binds -> - checkSigTyVars all_tyvars `thenM` \ all_tyvars' -> + checkSigTyVars all_tyvars `thenM_` - let - sel_name = idName sel_id - inline_prags = [ (is_inl, phase) - | L _ (InlineSig is_inl (L _ name) phase) <- prags, - name == sel_name ] - spec_prags = [ prag - | prag@(L _ (SpecSig (L _ name) _)) <- prags, - name == sel_name] - - -- Attach inline pragmas as appropriate - (final_meth_id, inlines) - | ((is_inline, phase) : _) <- inline_prags - = (meth_id `setInlinePragma` phase, - if is_inline then unitNameSet (idName meth_id) else emptyNameSet) - | otherwise - = (meth_id, emptyNameSet) - - meth_tvs' = take (length meth_tvs) all_tyvars' - poly_meth_bind = noLoc $ AbsBinds meth_tvs' + tcPrags meth_id (prag_fn sel_name) `thenM` \ prags -> + let + poly_meth_bind = noLoc $ AbsBinds meth_tvs (map instToId meth_dicts) - [(meth_tvs', final_meth_id, local_meth_id)] - inlines + [(meth_tvs, meth_id, local_meth_id, prags)] (lie_binds `unionBags` meth_bind) - - in - -- Deal with specialisation pragmas - -- The sel_name is what appears in the pragma - tcExtendLocalValEnv2 [(sel_name, final_meth_id)] ( - getLIE (tcSpecSigs spec_prags) `thenM` \ (spec_binds1, prag_lie) -> - - -- The prag_lie for a SPECIALISE pragma will mention the function itself, - -- so we have to simplify them away right now lest they float outwards! - bindInstsOfLocalFuns prag_lie [final_meth_id] `thenM` \ spec_binds2 -> - returnM (spec_binds1 `unionBags` spec_binds2) - ) `thenM` \ spec_binds -> - - returnM (poly_meth_bind `consBag` spec_binds) + in + returnM (unitBag poly_meth_bind) mkMethodBind :: InstOrigin @@ -437,8 +419,7 @@ mkMethodBind origin clas inst_tys meth_binds (sel_id, dm_info) Nothing -> mkDefMethRhs origin clas inst_tys sel_id loc dm_info `thenM` \ rhs -> -- Not infix decl - returnM (noLoc $ FunBind (noLoc meth_name) False - [mkSimpleMatch [] rhs placeHolderType]) + returnM (noLoc $ mkFunBind (noLoc meth_name) [mkSimpleMatch [] rhs]) ) `thenM` \ meth_bind -> returnM (mb_inst, (sel_id, meth_id, meth_bind)) @@ -464,8 +445,8 @@ mkMethId origin clas sel_id inst_tys ) if isSingleton preds then -- If it's the only one, make a 'method' - getInstLoc origin `thenM` \ inst_loc -> - newMethod inst_loc sel_id inst_tys preds tau `thenM` \ meth_inst -> + getInstLoc origin `thenM` \ inst_loc -> + newMethod inst_loc sel_id inst_tys `thenM` \ meth_inst -> returnM (Just meth_inst, instToId meth_inst) else -- If it's not the only one we need to be careful @@ -506,9 +487,9 @@ mkDefMethRhs origin clas inst_tys sel_id loc NoDefMeth (omittedMethodWarn sel_id) `thenM_` returnM error_rhs where - error_rhs = noLoc $ HsLam (mkSimpleMatch wild_pats simple_rhs placeHolderType) + error_rhs = noLoc $ HsLam (mkMatchGroup [mkSimpleMatch wild_pats simple_rhs]) simple_rhs = nlHsApp (nlHsVar (getName nO_METHOD_BINDING_ERROR_ID)) - (nlHsLit (HsStringPrim (mkFastString (stringToUtf8 error_msg)))) + (nlHsLit (HsStringPrim (mkFastString error_msg))) error_msg = showSDoc (hcat [ppr loc, text "|", ppr sel_id ]) -- When the type is of form t1 -> t2 -> t3 @@ -529,7 +510,7 @@ mkDefMethRhs origin clas inst_tys sel_id loc NoDefMeth -- Need two splits because the selector can have a type like -- forall a. Foo a => forall b. Eq b => ... (arg_tys, _) = tcSplitFunTys tau2 - wild_pats = [wildPat | ty <- arg_tys] + wild_pats = [nlWildPat | ty <- arg_tys] mkDefMethRhs origin clas inst_tys sel_id loc GenDefMeth = -- A generic default method @@ -566,8 +547,8 @@ mkDefMethRhs origin clas inst_tys sel_id loc GenDefMeth other -> Nothing other -> Nothing -isInstDecl InstanceDeclOrigin = True -isInstDecl ClassDeclOrigin = False +isInstDecl (SigOrigin (InstSkol _)) = True +isInstDecl (SigOrigin (ClsSkol _)) = False \end{code} @@ -577,8 +558,8 @@ isInstDecl ClassDeclOrigin = False find_bind sel_name meth_name binds = foldlBag seqMaybe Nothing (mapBag f binds) where - f (L loc1 (FunBind (L loc2 op_name) fix matches)) | op_name == sel_name - = Just (L loc1 (FunBind (L loc2 meth_name) fix matches)) + f (L loc1 bind@(FunBind { fun_id = L loc2 op_name })) | op_name == sel_name + = Just (L loc1 (bind { fun_id = L loc2 meth_name })) f _other = Nothing \end{code} @@ -678,10 +659,10 @@ getGenericBinds :: LHsBinds Name -> [(HsType Name, LHsBind Name)] -- them in finite map indexed by the type parameter in the definition. getGenericBinds binds = concat (map getGenericBind (bagToList binds)) -getGenericBind (L loc (FunBind id infixop matches)) +getGenericBind (L loc bind@(FunBind { fun_matches = MatchGroup matches ty })) = groupWith wrap (mapCatMaybes maybeGenericMatch matches) where - wrap ms = L loc (FunBind id infixop ms) + wrap ms = L loc (bind { fun_matches = MatchGroup ms ty }) getGenericBind _ = [] @@ -733,13 +714,14 @@ mkGenericInstance clas (hs_ty, binds) -- Make the dictionary function. getSrcSpanM `thenM` \ span -> + getOverlapFlag `thenM` \ overlap_flag -> newDFunName clas [inst_ty] (srcSpanStart span) `thenM` \ dfun_name -> let inst_theta = [mkClassPred clas [mkTyVarTy tv] | tv <- tyvars] dfun_id = mkDictFunId dfun_name tyvars inst_theta clas [inst_ty] + ispec = mkLocalInstance dfun_id overlap_flag in - - returnM (InstInfo { iDFunId = dfun_id, iBinds = VanillaInst binds [] }) + returnM (InstInfo { iSpec = ispec, iBinds = VanillaInst binds [] }) \end{code} @@ -801,7 +783,7 @@ dupGenericInsts tc_inst_infos ptext SLIT("All the type patterns for a generic type constructor must be identical") ] where - ppr_inst_ty (tc,inst) = ppr tc <+> ppr (simpleInstInfoTy inst) + ppr_inst_ty (_,inst) = ppr (simpleInstInfoTy inst) mixedGenericErr op = ptext SLIT("Can't mix generic and non-generic equations for class method") <+> quotes (ppr op)