X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcClassDcl.lhs;h=fbb450a19913ee51773d7aa29feabadd57dc1022;hb=9d7da331989abcd1844e9d03b8d1e4163796fa85;hp=e18982f2fc754de77ef0f8aee7484a38bf3d65e8;hpb=1bade0c9060d3aec4fd4590803d411d54f0ea927;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcClassDcl.lhs b/ghc/compiler/typecheck/TcClassDcl.lhs index e18982f..fbb450a 100644 --- a/ghc/compiler/typecheck/TcClassDcl.lhs +++ b/ghc/compiler/typecheck/TcClassDcl.lhs @@ -12,32 +12,25 @@ module TcClassDcl ( tcClassSigs, tcClassDecl2, #include "HsVersions.h" -import HsSyn ( TyClDecl(..), Sig(..), MonoBinds(..), HsType(..), - HsExpr(..), HsLit(..), Pat(WildPat), HsTyVarBndr(..), - HsExplicitForAll(..), - mkSimpleMatch, andMonoBinds, andMonoBindList, - isPragSig, placeHolderType, mkExplicitHsForAllTy - ) -import BasicTypes ( RecFlag(..), NewOrData(..) ) -import RnHsSyn ( RenamedTyClDecl, RenamedSig, - RenamedClassOpSig, RenamedMonoBinds, - maybeGenericMatch, extractHsTyVars - ) -import RnExpr ( rnExpr ) +import HsSyn +import RnHsSyn ( maybeGenericMatch, extractHsTyVars ) +import RnExpr ( rnLExpr ) import RnEnv ( lookupTopBndrRn, lookupImportedName ) -import TcHsSyn ( TcMonoBinds ) - -import Inst ( Inst, InstOrigin(..), instToId, newDicts, newMethod ) -import TcEnv ( tcLookupClass, tcExtendLocalValEnv2, tcExtendTyVarEnv2, - InstInfo(..), pprInstInfo, simpleInstInfoTyCon, simpleInstInfoTy, +import Inst ( instToId, newDicts, newDictsAtLoc, newMethod, getOverlapFlag ) +import InstEnv ( mkLocalInstance ) +import TcEnv ( tcLookupLocatedClass, + tcExtendTyVarEnv, + 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 ) +import TcHsType ( TcSigInfo(..), tcHsKindedType, tcHsSigType ) +import TcSimplify ( tcSimplifyCheck ) import TcUnify ( checkSigTyVars, sigCtxt ) -import TcMType ( tcInstTyVars, UserTypeCtxt( GenPatCtxt ) ) -import TcType ( Type, TyVarDetails(..), TcType, TcThetaType, TcTyVar, +import TcMType ( tcSkolSigTyVars, UserTypeCtxt( GenPatCtxt ), tcSkolType ) +import TcType ( Type, SkolemInfo(ClsSkol, InstSkol, SigSkol), + TcType, TcThetaType, TcTyVar, mkTyVarTys, mkClassPred, tcSplitSigmaTy, tcSplitFunTys, tcIsTyVarTy, tcSplitTyConApp_maybe, tcSplitForAllTys, tcSplitPhiTy, getClassPredTys_maybe, mkPhiTy, mkTyVarTy @@ -48,26 +41,26 @@ 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, emptyNameEnv, unitNameEnv, plusNameEnv ) -import NameSet ( emptyNameSet, unitNameSet, nameSetToList ) +import NameEnv ( NameEnv, lookupNameEnv, mkNameEnv ) +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 ErrUtils ( dumpIfSet, dumpIfSet_dyn ) +import DynFlags +import ErrUtils ( dumpIfSet_dyn ) import Util ( count, lengthIs, isSingleton, lengthExceeds ) import Unique ( Uniquable(..) ) import ListSetOps ( equivClassesByUniq, minusList ) -import SrcLoc ( SrcLoc ) +import SrcLoc ( Located(..), srcSpanStart, unLoc, noLoc ) import Maybes ( seqMaybe, isJust, mapCatMaybes ) import List ( partition ) +import BasicTypes ( RecFlag(..) ) +import Bag import FastString \end{code} @@ -114,8 +107,8 @@ Death to "ExpandingDicts". \begin{code} tcClassSigs :: Name -- Name of the class - -> [RenamedClassOpSig] - -> RenamedMonoBinds + -> [LSig Name] + -> LHsBinds Name -> TcM [TcMethInfo] type TcMethInfo = (Name, DefMeth, Type) -- A temporary intermediate, to communicate @@ -124,35 +117,28 @@ 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@(Sig n _ _) <- sigs] - op_names = [n | sig@(Sig n _ _) <- op_sigs] + op_sigs = [sig | sig@(L _ (TypeSig _ _)) <- sigs] + op_names = [n | sig@(L _ (TypeSig (L _ n) _)) <- op_sigs] - -checkDefaultBinds :: Name -> [Name] -> RenamedMonoBinds - -> TcM (NameEnv Bool) + +checkDefaultBinds :: Name -> [Name] -> LHsBinds Name -> TcM (NameEnv Bool) -- Check default bindings -- a) must be for a class op for this class -- b) must be all generic or all non-generic -- and return a mapping from class-op to Bool -- where True <=> it's a generic default method +checkDefaultBinds clas ops binds + = do dm_infos <- mapM (addLocM (checkDefaultBind clas ops)) (bagToList binds) + return (mkNameEnv dm_infos) -checkDefaultBinds clas ops EmptyMonoBinds - = returnM emptyNameEnv - -checkDefaultBinds clas ops (AndMonoBinds b1 b2) - = do { dm_info1 <- checkDefaultBinds clas ops b1 - ; dm_info2 <- checkDefaultBinds clas ops b2 - ; returnM (dm_info1 `plusNameEnv` dm_info2) } - -checkDefaultBinds clas ops (FunMonoBind op _ matches loc) - = addSrcLoc loc $ do - { -- Check that the op is from this class +checkDefaultBind clas ops (FunBind (L _ op) _ (MatchGroup matches _) _) + = do { -- Check that the op is from this class checkTc (op `elem` ops) (badMethodErr clas op) -- Check that all the defns ar generic, or none are ; checkTc (all_generic || none_generic) (mixedGenericErr op) - ; returnM (unitNameEnv op all_generic) + ; returnM (op, all_generic) } where n_generic = count (isJust . maybeGenericMatch) matches @@ -161,11 +147,11 @@ checkDefaultBinds clas ops (FunMonoBind op _ matches loc) tcClassSig :: NameEnv Bool -- Info about default methods; - -> RenamedClassOpSig + -> LSig Name -> TcM TcMethInfo -tcClassSig dm_env (Sig op_name op_hs_ty src_loc) - = addSrcLoc src_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 @@ -240,14 +226,14 @@ dfun.Foo.List (generic default methods have by now turned into instance declarations) \begin{code} -tcClassDecl2 :: RenamedTyClDecl -- The class declaration - -> TcM (TcMonoBinds, [Id]) +tcClassDecl2 :: LTyClDecl Name -- The class declaration + -> TcM (LHsBinds Id, [Id]) -tcClassDecl2 (ClassDecl {tcdName = class_name, tcdSigs = sigs, - tcdMeths = default_binds, tcdLoc = src_loc}) - = recoverM (returnM (EmptyMonoBinds, [])) $ - addSrcLoc src_loc $ - tcLookupClass class_name `thenM` \ clas -> +tcClassDecl2 (L loc (ClassDecl {tcdLName = class_name, tcdSigs = sigs, + tcdMeths = default_binds})) + = recoverM (returnM (emptyLHsBinds, [])) $ + setSrcSpan loc $ + tcLookupLocatedClass class_name `thenM` \ clas -> -- We make a separate binding for each default method. -- At one time I used a single AbsBinds for all of them, thus @@ -259,8 +245,8 @@ tcClassDecl2 (ClassDecl {tcdName = class_name, tcdSigs = sigs, -- default methods. Better to make separate AbsBinds for each let (tyvars, _, _, op_items) = classBigSig clas - prags = filter isPragSig 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 @@ -271,46 +257,44 @@ tcClassDecl2 (ClassDecl {tcdName = class_name, tcdSigs = sigs, -- (If necessary we can fix that, but we don't have a convenient Id to hand.) in mapAndUnzipM tc_dm dm_sel_ids `thenM` \ (defm_binds, dm_ids_s) -> - returnM (andMonoBindList defm_binds, concat 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 `andMonoBinds` defm_bind) - in - returnM (full_bind, [local_dm_id]) + ; let + (_,dm_inst_id,_) = meth_info + full_bind = AbsBinds + clas_tyvars + [instToId this_dict] + [(clas_tyvars, local_dm_id, dm_inst_id, [])] + -- No inlines (yet) + (dict_binds `unionBags` defm_bind) + ; returnM (noLoc full_bind, [local_dm_id]) }} mkDefMethRdrName :: Id -> RdrName mkDefMethRdrName sel_id = mkDerivedRdrName (idName sel_id) mkDefaultMethodOcc @@ -331,33 +315,49 @@ tyvar sets. \begin{code} type MethodSpec = (Id, -- Global selector Id Id, -- Local Id (class tyvars instantiated) - RenamedMonoBinds) -- Binding for the method + 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 - -> [RenamedSig] -- Pragmas (e.g. inline pragmas) + -> TcPragFun -- Pragmas (e.g. inline pragmas) -> MethodSpec -- Details of this method - -> TcM TcMonoBinds + -> 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) - = -- Check the bindings; first adding inst_tyvars to the envt + = 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 + -- the type enviroment, and we get a tcLookup failure on $dmeth later. + + -- 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 ( + + let -- Fake up a TcSigInfo to pass to tcMonoBinds + rigid_info = SigSkol (idName meth_id) + in + tcSkolType rigid_info (idType meth_id) `thenM` \ (tyvars', theta', tau') -> + getInstLoc (SigOrigin rigid_info) `thenM` \ loc -> + let meth_sig = TcSigInfo { sig_id = meth_id, sig_tvs = tyvars', sig_scoped = [], + sig_theta = theta', sig_tau = tau', sig_loc = loc } + lookup_sig name = ASSERT( name == idName meth_id ) + Just meth_sig + in + tcExtendTyVarEnv inst_tyvars ( addErrCtxt (methodCtxt sel_id) $ getLIE $ - tcMonoBinds meth_bind [meth_sig] NonRecursive - ) `thenM` \ ((meth_bind,_), meth_lie) -> + 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 @@ -367,63 +367,34 @@ tcMethodBind xtve inst_tyvars inst_theta avail_insts prags -- -- We do this for each method independently to localise error messages - let - TySigInfo meth_id meth_tvs meth_theta _ 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 + addErrCtxtM (sigCtxt sel_id inst_tyvars inst_theta (idType meth_id)) $ + newDictsAtLoc (sig_loc meth_sig) (sig_theta meth_sig) `thenM` \ meth_dicts -> + let + meth_tvs = sig_tvs meth_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) - | InlineSig is_inl name phase _ <- prags, - name == sel_name ] - spec_prags = [ prag - | prag@(SpecSig 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 = AbsBinds meth_tvs' + tcPrags meth_id (prag_fn sel_name) `thenM` \ prags -> + let + [(_,_,local_meth_id)] = mono_bind_infos + poly_meth_bind = noLoc $ AbsBinds meth_tvs (map instToId meth_dicts) - [(meth_tvs', final_meth_id, local_meth_id)] - inlines - (lie_binds `andMonoBinds` 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 `andMonoBinds` spec_binds2) - ) `thenM` \ spec_binds -> - - returnM (poly_meth_bind `andMonoBinds` spec_binds) + [(meth_tvs, meth_id, local_meth_id, prags)] + (lie_binds `unionBags` meth_bind) + in + returnM (unitBag poly_meth_bind) mkMethodBind :: InstOrigin -> Class -> [TcType] -- Class and instance types - -> RenamedMonoBinds -- Method binding (pick the right one from in here) + -> LHsBinds Name -- Method binding (pick the right one from in here) -> ClassOpItem -> TcM (Maybe Inst, -- Method inst MethodSpec) @@ -437,13 +408,16 @@ mkMethodBind origin clas inst_tys meth_binds (sel_id, dm_info) in -- Figure out what method binding to use -- If the user suppplied one, use it, else construct a default one - getSrcLocM `thenM` \ loc -> + getSrcSpanM `thenM` \ loc -> (case find_bind (idName sel_id) meth_name meth_binds of Just user_bind -> returnM user_bind - Nothing -> mkDefMethRhs origin clas inst_tys sel_id loc dm_info `thenM` \ rhs -> - returnM (FunMonoBind meth_name False -- Not infix decl - [mkSimpleMatch [] rhs placeHolderType loc] loc) - ) `thenM` \ meth_bind -> + Nothing -> + mkDefMethRhs origin clas inst_tys sel_id loc dm_info `thenM` \ rhs -> + -- Not infix decl + returnM (noLoc $ FunBind (noLoc meth_name) False + (mkMatchGroup [mkSimpleMatch [] rhs]) + placeHolderNames) + ) `thenM` \ meth_bind -> returnM (mb_inst, (sel_id, meth_id, meth_bind)) @@ -482,10 +456,11 @@ mkMethId origin clas sel_id inst_tys -- BUT: it can't be a Method any more, because it breaks -- INVARIANT 2 of methods. (See the data decl for Inst.) newUnique `thenM` \ uniq -> - getSrcLocM `thenM` \ loc -> + getSrcSpanM `thenM` \ loc -> let real_tau = mkPhiTy (tail preds) tau - meth_id = mkUserLocal (getOccName sel_id) uniq real_tau loc + meth_id = mkUserLocal (getOccName sel_id) uniq real_tau + (srcSpanStart loc) --TODO in returnM (Nothing, meth_id) @@ -497,7 +472,7 @@ mkDefMethRhs origin clas inst_tys sel_id loc DefMeth lookupImportedName (mkDefMethRdrName sel_id) `thenM` \ dm_name -> -- Might not be imported, but will be an OrigName traceRn (text "mkDefMeth" <+> ppr dm_name) `thenM_` - returnM (HsVar dm_name) + returnM (nlHsVar dm_name) mkDefMethRhs origin clas inst_tys sel_id loc NoDefMeth = -- No default method @@ -509,9 +484,9 @@ mkDefMethRhs origin clas inst_tys sel_id loc NoDefMeth (omittedMethodWarn sel_id) `thenM_` returnM error_rhs where - error_rhs = HsLam (mkSimpleMatch wild_pats simple_rhs placeHolderType loc) - simple_rhs = HsApp (HsVar (getName nO_METHOD_BINDING_ERROR_ID)) - (HsLit (HsStringPrim (mkFastString (stringToUtf8 error_msg)))) + error_rhs = noLoc $ HsLam (mkMatchGroup [mkSimpleMatch wild_pats simple_rhs]) + simple_rhs = nlHsApp (nlHsVar (getName nO_METHOD_BINDING_ERROR_ID)) + (nlHsLit (HsStringPrim (mkFastString error_msg))) error_msg = showSDoc (hcat [ppr loc, text "|", ppr sel_id ]) -- When the type is of form t1 -> t2 -> t3 @@ -532,32 +507,31 @@ 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 placeHolderType | ty <- arg_tys] + wild_pats = [nlWildPat | ty <- arg_tys] mkDefMethRhs origin clas inst_tys sel_id loc GenDefMeth - = -- A generic default method - -- If the method is defined generically, we can only do the job if the + = -- A generic default method + -- If the method is defined generically, we can only do the job if the -- instance declaration is for a single-parameter type class with -- a type constructor applied to type arguments in the instance decl -- (checkTc, so False provokes the error) - ASSERT( isInstDecl origin ) -- We never get here from a class decl - - checkTc (isJust maybe_tycon) - (badGenericInstance sel_id (notSimple inst_tys)) `thenM_` - checkTc (tyConHasGenerics tycon) - (badGenericInstance sel_id (notGeneric tycon)) `thenM_` - - ioToTcRn (dumpIfSet opt_PprStyle_Debug "Generic RHS" stuff) `thenM_` - - -- Rename it before returning it - rnExpr rhs `thenM` \ (rn_rhs, _) -> - returnM rn_rhs + ASSERT( isInstDecl origin ) -- We never get here from a class decl + do { checkTc (isJust maybe_tycon) + (badGenericInstance sel_id (notSimple inst_tys)) + ; checkTc (tyConHasGenerics tycon) + (badGenericInstance sel_id (notGeneric tycon)) + + ; dflags <- getDOpts + ; ioToTcRn (dumpIfSet_dyn dflags Opt_D_dump_deriv "Filling in method body" + (vcat [ppr clas <+> ppr inst_tys, + nest 2 (ppr sel_id <+> equals <+> ppr rhs)])) + + -- Rename it before returning it + ; (rn_rhs, _) <- rnLExpr rhs + ; returnM rn_rhs } where rhs = mkGenericRhs sel_id clas_tyvar tycon - stuff = vcat [ppr clas <+> ppr inst_tys, - nest 4 (ppr sel_id <+> equals <+> ppr rhs)] - -- The tycon is only used in the generic case, and in that -- case we require that the instance decl is for a single-parameter -- type class with type variable arguments: @@ -570,19 +544,20 @@ 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} \begin{code} -- The renamer just puts the selector ID as the binder in the method binding -- but we must use the method name; so we substitute it here. Crude but simple. -find_bind sel_name meth_name (FunMonoBind op_name fix matches loc) - | op_name == sel_name = Just (FunMonoBind meth_name fix matches loc) -find_bind sel_name meth_name (AndMonoBinds b1 b2) - = find_bind sel_name meth_name b1 `seqMaybe` find_bind sel_name meth_name b2 -find_bind sel_name meth_name other = Nothing -- Default case +find_bind sel_name meth_name binds + = foldlBag seqMaybe Nothing (mapBag f binds) + where + f (L loc1 (FunBind (L loc2 op_name) fix matches fvs)) | op_name == sel_name + = Just (L loc1 (FunBind (L loc2 meth_name) fix matches fvs)) + f _other = Nothing \end{code} @@ -617,9 +592,9 @@ gives rise to the instance declarations \begin{code} -getGenericInstances :: [RenamedTyClDecl] -> TcM [InstInfo] +getGenericInstances :: [LTyClDecl Name] -> TcM [InstInfo] getGenericInstances class_decls - = do { gen_inst_infos <- mappM get_generics class_decls + = do { gen_inst_infos <- mappM (addLocM get_generics) class_decls ; let { gen_inst_info = concat gen_inst_infos } -- Return right away if there is no generic stuff @@ -629,24 +604,24 @@ getGenericInstances class_decls -- Otherwise print it out { dflags <- getDOpts ; ioToTcRn (dumpIfSet_dyn dflags Opt_D_dump_deriv "Generic instances" - (vcat (map pprInstInfo gen_inst_info))) + (vcat (map pprInstInfoDetails gen_inst_info))) ; returnM gen_inst_info }} -get_generics decl@(ClassDecl {tcdName = class_name, tcdMeths = def_methods, tcdLoc = loc}) +get_generics decl@(ClassDecl {tcdLName = class_name, tcdMeths = def_methods}) | null generic_binds = returnM [] -- The comon case: no generic default methods | otherwise -- A source class decl with generic default methods = recoverM (returnM []) $ tcAddDeclCtxt decl $ - tcLookupClass class_name `thenM` \ clas -> + tcLookupLocatedClass class_name `thenM` \ clas -> -- Group by type, and -- make an InstInfo out of each group let - groups = groupWith andMonoBindList generic_binds + groups = groupWith listToBag generic_binds in - mappM (mkGenericInstance clas loc) groups `thenM` \ inst_infos -> + mappM (mkGenericInstance clas) groups `thenM` \ inst_infos -> -- Check that there is only one InstInfo for each type constructor -- The main way this can fail is if you write @@ -670,24 +645,23 @@ get_generics decl@(ClassDecl {tcdName = class_name, tcdMeths = def_methods, tcdL checkTc (null missing) (missingGenericInstances missing) `thenM_` returnM inst_infos - where - generic_binds :: [(HsType Name, RenamedMonoBinds)] + generic_binds :: [(HsType Name, LHsBind Name)] generic_binds = getGenericBinds def_methods --------------------------------- -getGenericBinds :: RenamedMonoBinds -> [(HsType Name, RenamedMonoBinds)] +getGenericBinds :: LHsBinds Name -> [(HsType Name, LHsBind Name)] -- Takes a group of method bindings, finds the generic ones, and returns -- them in finite map indexed by the type parameter in the definition. +getGenericBinds binds = concat (map getGenericBind (bagToList binds)) -getGenericBinds EmptyMonoBinds = [] -getGenericBinds (AndMonoBinds m1 m2) = getGenericBinds m1 ++ getGenericBinds m2 - -getGenericBinds (FunMonoBind id infixop matches loc) +getGenericBind (L loc (FunBind id infixop (MatchGroup matches ty) fvs)) = groupWith wrap (mapCatMaybes maybeGenericMatch matches) where - wrap ms = FunMonoBind id infixop ms loc + wrap ms = L loc (FunBind id infixop (MatchGroup ms ty) fvs) +getGenericBind _ + = [] groupWith :: ([a] -> b) -> [(HsType Name, a)] -> [(HsType Name, b)] groupWith op [] = [] @@ -697,23 +671,26 @@ groupWith op ((t,v):prs) = (t, op (v:vs)) : groupWith op rest (this,rest) = partition same_t prs same_t (t',v) = t `eqPatType` t' +eqPatLType :: LHsType Name -> LHsType Name -> Bool +eqPatLType t1 t2 = unLoc t1 `eqPatType` unLoc t2 + eqPatType :: HsType Name -> HsType Name -> Bool -- A very simple equality function, only for -- type patterns in generic function definitions. eqPatType (HsTyVar v1) (HsTyVar v2) = v1==v2 -eqPatType (HsAppTy s1 t1) (HsAppTy s2 t2) = s1 `eqPatType` s2 && t2 `eqPatType` t2 -eqPatType (HsOpTy s1 op1 t1) (HsOpTy s2 op2 t2) = s1 `eqPatType` s2 && t2 `eqPatType` t2 && op1 == op2 +eqPatType (HsAppTy s1 t1) (HsAppTy s2 t2) = s1 `eqPatLType` s2 && t2 `eqPatLType` t2 +eqPatType (HsOpTy s1 op1 t1) (HsOpTy s2 op2 t2) = s1 `eqPatLType` s2 && t2 `eqPatLType` t2 && unLoc op1 == unLoc op2 eqPatType (HsNumTy n1) (HsNumTy n2) = n1 == n2 -eqPatType (HsParTy t1) t2 = t1 `eqPatType` t2 -eqPatType t1 (HsParTy t2) = t1 `eqPatType` t2 +eqPatType (HsParTy t1) t2 = unLoc t1 `eqPatType` t2 +eqPatType t1 (HsParTy t2) = t1 `eqPatType` unLoc t2 eqPatType _ _ = False --------------------------------- -mkGenericInstance :: Class -> SrcLoc - -> (HsType Name, RenamedMonoBinds) +mkGenericInstance :: Class + -> (HsType Name, LHsBinds Name) -> TcM InstInfo -mkGenericInstance clas loc (hs_ty, binds) +mkGenericInstance clas (hs_ty, binds) -- Make a generic instance declaration -- For example: instance (C a, C b) => C (a+b) where { binds } @@ -721,8 +698,8 @@ mkGenericInstance clas loc (hs_ty, binds) -- and wrap them as forall'd tyvars, so that kind inference -- works in the standard way let - sig_tvs = map UserTyVar (nameSetToList (extractHsTyVars hs_ty)) - hs_forall_ty = mkExplicitHsForAllTy sig_tvs [] hs_ty + sig_tvs = map (noLoc.UserTyVar) (nameSetToList (extractHsTyVars (noLoc hs_ty))) + hs_forall_ty = noLoc $ mkExplicitHsForAllTy sig_tvs (noLoc []) (noLoc hs_ty) in -- Type-check the instance type, and check its form tcHsSigType GenPatCtxt hs_forall_ty `thenM` \ forall_inst_ty -> @@ -733,13 +710,15 @@ mkGenericInstance clas loc (hs_ty, binds) (badGenericInstanceType binds) `thenM_` -- Make the dictionary function. - newDFunName clas [inst_ty] loc `thenM` \ dfun_name -> + 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} @@ -751,9 +730,7 @@ mkGenericInstance clas loc (hs_ty, binds) \begin{code} tcAddDeclCtxt decl thing_inside - = addSrcLoc (tcdLoc decl) $ - addErrCtxt ctxt $ - thing_inside + = addErrCtxt ctxt thing_inside where thing = case decl of ClassDecl {} -> "class" @@ -803,7 +780,7 @@ 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)