X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcInstDcls.lhs;h=ba57563806500a6094a0432f507c10db4fb1794f;hb=15cb792d18b1094e98c035dca6ecec5dad516056;hp=6ff97e36af653ab014f2f60de7ea2d79c2758286;hpb=d937e740b0c861a40243a83ac119de76775bd880;p=ghc-hetmet.git diff --git a/compiler/typecheck/TcInstDcls.lhs b/compiler/typecheck/TcInstDcls.lhs index 6ff97e3..ba57563 100644 --- a/compiler/typecheck/TcInstDcls.lhs +++ b/compiler/typecheck/TcInstDcls.lhs @@ -14,9 +14,9 @@ import TcClassDcl ( tcMethodBind, mkMethodBind, badMethodErr, tcClassDecl2, getGenericInstances ) import TcRnMonad import TcMType ( tcSkolSigType, checkValidInstance, checkValidInstHead ) -import TcType ( mkClassPred, tcSplitSigmaTy, tcSplitDFunHead, mkTyVarTys, - SkolemInfo(InstSkol), tcSplitDFunTy ) -import Inst ( tcInstClassOp, newDicts, instToId, showLIE, +import TcType ( mkClassPred, tcSplitSigmaTy, tcSplitDFunHead, + SkolemInfo(InstSkol), tcSplitDFunTy, mkFunTy ) +import Inst ( newDictBndr, newDictBndrs, instToId, showLIE, getOverlapFlag, tcExtendLocalInstEnv ) import InstEnv ( mkLocalInstance, instanceDFunId ) import TcDeriv ( tcDeriving ) @@ -25,11 +25,15 @@ import TcEnv ( InstInfo(..), InstBindings(..), ) import TcHsType ( kcHsSigType, tcHsKindedType ) import TcUnify ( checkSigTyVars ) -import TcSimplify ( tcSimplifyCheck, tcSimplifySuperClasses ) -import Type ( zipOpenTvSubst, substTheta, substTys ) -import DataCon ( classDataCon ) +import TcSimplify ( tcSimplifySuperClasses ) +import Type ( zipOpenTvSubst, substTheta, mkTyConApp, mkTyVarTy ) +import Coercion ( mkAppCoercion, mkAppsCoercion ) +import TyCon ( TyCon, newTyConCo ) +import DataCon ( classDataCon, dataConTyCon, dataConInstArgTys ) import Class ( classBigSig ) -import Var ( Id, idName, idType ) +import Var ( TyVar, Id, idName, idType ) +import Id ( mkSysLocal ) +import UniqSupply ( uniqsFromSupply, splitUniqSupply ) import MkId ( mkDictFunId ) import Name ( Name, getSrcLoc ) import Maybe ( catMaybes ) @@ -305,7 +309,7 @@ First comes the easy case of a non-local instance decl. tcInstDecl2 :: InstInfo -> TcM (LHsBinds Id) -- Returns a binding for the dfun --- +------------------------ -- Derived newtype instances -- -- We need to make a copy of the dictionary we are deriving from @@ -330,74 +334,66 @@ tcInstDecl2 (InstInfo { iSpec = ispec, rigid_info = InstSkol dfun_id origin = SigOrigin rigid_info inst_ty = idType dfun_id - maybe_co_con = newTyConCo tycon + ; inst_loc <- getInstLoc origin ; (tvs, theta, inst_head) <- tcSkolSigType rigid_info inst_ty - ; dicts <- newDicts origin theta - ; uniqs <- newUniqueSupply - ; let (rep_dict_id:sc_dict_ids) = map instToId dicts - -- (Here, wee are relying on the order of dictionary + ; dicts <- newDictBndrs inst_loc theta + ; uniqs <- newUniqueSupply + ; let (cls, cls_inst_tys) = tcSplitDFunHead inst_head + ; this_dict <- newDictBndr inst_loc (mkClassPred cls rep_tys) + ; let (rep_dict_id:sc_dict_ids) + | null dicts = [instToId this_dict] + | otherwise = map instToId dicts + + -- (Here, we are relying on the order of dictionary -- arguments built by NewTypeDerived in TcDeriv.) - wrap_fn = CoTyLams tvs <.> CoLams dict_ids + wrap_fn = mkCoTyLams tvs <.> mkCoLams (rep_dict_id:sc_dict_ids) - coerced_rep_dict = mkHsCoerce co_fn (HsVar rep_dict_id) + coerced_rep_dict = mkHsCoerce (co_fn tvs cls_tycon) (HsVar rep_dict_id) - body | null sc_dicts = coerced_rep_dict - | otherwise = HsCase coerced_rep_dict $ - MatchGroup [the_match] inst_head - the_match = mkSimpleMatch [the_pat] the_rhs - op_ids = zipWith (mkSysLocal FSLIT("op")) - (uniqsFromSupply uniqs) op_tys - the_pat = ConPatOut { pat_con = cls_data_con, pat_tvs = [], - pat_dicts = map (WildPat . idType) sc_dict_ids, - pat_binds = emptyDictBinds, - pat_args = PrefixCon (map VarPat op_ids), - pat_ty = } - the_rhs = mkHsApps (dataConWrapId cls_data_con) types sc_dict_ids (map HsVar op_ids) - - ; return (unitBag (VarBind dfun_id (mkHsCoerce wrap_fn body))) } - where - co_fn :: ExprCoFn - co_fn | Just co_con <- newTyConCo tycon - = ExprCoFn (mkAppCoercion (mkAppsCoercion tycon rep_tys) - (mkTyConApp co_con tvs)) - | otherwise - = idCoerecion + body | null sc_dict_ids = coerced_rep_dict + | otherwise = HsCase (noLoc coerced_rep_dict) $ + MatchGroup [the_match] (mkFunTy in_dict_ty inst_head) + in_dict_ty = mkTyConApp cls_tycon cls_inst_tys -tcMethods origin clas inst_tyvars' dfun_theta' inst_tys' - avail_insts op_items (NewTypeDerived rep_tys) - = getInstLoc origin `thenM` \ inst_loc -> - mapAndUnzip3M (do_one inst_loc) op_items `thenM` \ (meth_ids, meth_binds, rhs_insts) -> - - tcSimplifyCheck - (ptext SLIT("newtype derived instance")) - inst_tyvars' avail_insts rhs_insts `thenM` \ lie_binds -> + the_match = mkSimpleMatch [noLoc the_pat] the_rhs + the_rhs = mkHsConApp cls_data_con cls_inst_tys (map HsVar (sc_dict_ids ++ op_ids)) - -- I don't think we have to do the checkSigTyVars thing - - returnM (meth_ids, lie_binds `unionBags` listToBag meth_binds) + (uniqs1, uniqs2) = splitUniqSupply uniqs + op_ids = zipWith (mkSysLocal FSLIT("op")) + (uniqsFromSupply uniqs1) op_tys + + dict_ids = zipWith (mkSysLocal FSLIT("dict")) + (uniqsFromSupply uniqs2) (map idType sc_dict_ids) + + the_pat = ConPatOut { pat_con = noLoc cls_data_con, pat_tvs = [], + pat_dicts = dict_ids, + pat_binds = emptyLHsBinds, + pat_args = PrefixCon (map nlVarPat op_ids), + pat_ty = in_dict_ty} + + cls_data_con = classDataCon cls + cls_tycon = dataConTyCon cls_data_con + cls_arg_tys = dataConInstArgTys cls_data_con cls_inst_tys + + n_dict_args = if length dicts == 0 then 0 else length dicts - 1 + op_tys = drop n_dict_args cls_arg_tys + + dict = mkHsCoerce wrap_fn body + ; return (unitBag (noLoc $ VarBind dfun_id (noLoc dict))) } where - do_one inst_loc (sel_id, _) - = -- The binding is like "op @ NewTy = op @ RepTy" - -- Make the *binder*, like in mkMethodBind - tcInstClassOp inst_loc sel_id inst_tys' `thenM` \ meth_inst -> - - -- Make the *occurrence on the rhs* - tcInstClassOp inst_loc sel_id rep_tys' `thenM` \ rhs_inst -> - let - meth_id = instToId meth_inst - in - return (meth_id, noLoc (VarBind meth_id (nlHsVar (instToId rhs_inst))), rhs_inst) - - -- Instantiate rep_tys with the relevant type variables - -- This looks a bit odd, because inst_tyvars' are the skolemised version - -- of the type variables in the instance declaration; but rep_tys doesn't - -- have the skolemised version, so we substitute them in here - rep_tys' = substTys subst rep_tys - subst = zipOpenTvSubst inst_tyvars' (mkTyVarTys inst_tyvars') - + co_fn :: [TyVar] -> TyCon -> ExprCoFn + co_fn tvs cls_tycon | Just co_con <- newTyConCo tycon + = ExprCoFn (mkAppCoercion -- (mkAppsCoercion + (mkTyConApp cls_tycon []) + -- rep_tys) + (mkTyConApp co_con (map mkTyVarTy tvs))) + | otherwise + = idCoercion +------------------------ +-- Ordinary instances tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = VanillaInst monobinds uprags }) = let @@ -424,9 +420,11 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = VanillaInst monobinds uprags }) origin = SigOrigin rigid_info in -- Create dictionary Ids from the specified instance contexts. - newDicts InstScOrigin sc_theta' `thenM` \ sc_dicts -> - newDicts origin dfun_theta' `thenM` \ dfun_arg_dicts -> - newDicts origin [mkClassPred clas inst_tys'] `thenM` \ [this_dict] -> + getInstLoc InstScOrigin `thenM` \ sc_loc -> + newDictBndrs sc_loc sc_theta' `thenM` \ sc_dicts -> + getInstLoc origin `thenM` \ inst_loc -> + newDictBndrs inst_loc dfun_theta' `thenM` \ dfun_arg_dicts -> + newDictBndr inst_loc (mkClassPred clas inst_tys') `thenM` \ this_dict -> -- Default-method Ids may be mentioned in synthesised RHSs, -- but they'll already be in the environment. @@ -451,7 +449,7 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = VanillaInst monobinds uprags }) checkSigTyVars inst_tyvars' `thenM_` -- Deal with 'SPECIALISE instance' pragmas - tcPrags dfun_id (filter isSpecInstLSig prags) `thenM` \ prags -> + tcPrags dfun_id (filter isSpecInstLSig uprags) `thenM` \ prags -> -- Create the result bindings let @@ -551,44 +549,6 @@ tcMethods origin clas inst_tyvars' dfun_theta' inst_tys' mapM tc_method_bind meth_infos `thenM` \ meth_binds_s -> returnM (meth_ids, unionManyBags meth_binds_s) -v v v v v v v -************* - - --- Derived newtype instances -tcMethods origin clas inst_tyvars' dfun_theta' inst_tys' - avail_insts op_items (NewTypeDerived maybe_co rep_tys) - = getInstLoc origin `thenM` \ inst_loc -> - mapAndUnzip3M (do_one inst_loc) op_items `thenM` \ (meth_ids, meth_binds, rhs_insts) -> - - tcSimplifyCheck - (ptext SLIT("newtype derived instance")) - inst_tyvars' avail_insts rhs_insts `thenM` \ lie_binds -> - - -- I don't think we have to do the checkSigTyVars thing - - returnM (meth_ids, lie_binds `unionBags` listToBag meth_binds) - - where - do_one inst_loc (sel_id, _) - = -- The binding is like "op @ NewTy = op @ RepTy" - -- Make the *binder*, like in mkMethodBind - tcInstClassOp inst_loc sel_id inst_tys' `thenM` \ meth_inst -> - - -- Make the *occurrence on the rhs* - tcInstClassOp inst_loc sel_id rep_tys' `thenM` \ rhs_inst -> - let - meth_id = instToId meth_inst - in - return (meth_id, noLoc (VarBind meth_id (nlHsVar (instToId rhs_inst))), rhs_inst) - - -- Instantiate rep_tys with the relevant type variables - -- This looks a bit odd, because inst_tyvars' are the skolemised version - -- of the type variables in the instance declaration; but rep_tys doesn't - -- have the skolemised version, so we substitute them in here - rep_tys' = substTys subst rep_tys - subst = zipOpenTvSubst inst_tyvars' (mkTyVarTys inst_tyvars') -^ ^ ^ ^ ^ ^ ^ \end{code}