X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcInstDcls.lhs;h=c04f4a2e40d22572c6550d3d52528a42b480b7b0;hb=1f4bc1f36380776c68431dbc3b5fa41dd6d2182e;hp=1bc70992c391a0bf25d159535de405589de0dd95;hpb=b7a8d2059f982599d31d14395c6628a049ec5179;p=ghc-hetmet.git diff --git a/compiler/typecheck/TcInstDcls.lhs b/compiler/typecheck/TcInstDcls.lhs index 1bc7099..c04f4a2 100644 --- a/compiler/typecheck/TcInstDcls.lhs +++ b/compiler/typecheck/TcInstDcls.lhs @@ -21,7 +21,6 @@ import FamInst import FamInstEnv import TcDeriv import TcEnv -import RnEnv ( lookupGlobalOccRn ) import RnSource ( addTcgDUs ) import TcHsType import TcUnify @@ -33,6 +32,7 @@ import DataCon import Class import Var import CoreUnfold ( mkDFunUnfolding ) +import CoreSyn ( Expr(Var) ) import Id import MkId import Name @@ -314,16 +314,16 @@ tcInstDecls1 tycl_decls inst_decls deriv_decls -- round) -- (1) Do class and family instance declarations - ; let { idxty_decls = filter (isFamInstDecl . unLoc) tycl_decls } + ; idx_tycons <- mapAndRecoverM (tcFamInstDecl TopLevel) $ + filter (isFamInstDecl . unLoc) tycl_decls ; local_info_tycons <- mapAndRecoverM tcLocalInstDecl1 inst_decls - ; idx_tycons <- mapAndRecoverM tcIdxTyInstDeclTL idxty_decls ; let { (local_info, at_tycons_s) = unzip local_info_tycons ; at_idx_tycons = concat at_tycons_s ++ idx_tycons ; clas_decls = filter (isClassDecl.unLoc) tycl_decls ; implicit_things = concatMap implicitTyThings at_idx_tycons - ; aux_binds = mkAuxBinds at_idx_tycons + ; aux_binds = mkRecSelBinds at_idx_tycons } -- (2) Add the tycons of indexed types and their implicit @@ -335,9 +335,9 @@ tcInstDecls1 tycl_decls inst_decls deriv_decls -- Next, construct the instance environment so far, consisting -- of - -- a) local instance decls - -- b) generic instances - -- c) local family instance decls + -- (a) local instance decls + -- (b) generic instances + -- (c) local family instance decls ; addInsts local_info $ addInsts generic_inst_info $ addFamInsts at_idx_tycons $ do { @@ -357,27 +357,6 @@ tcInstDecls1 tycl_decls inst_decls deriv_decls generic_inst_info ++ deriv_inst_info ++ local_info, aux_binds `plusHsValBinds` deriv_binds) }}} - where - -- Make sure that toplevel type instance are not for associated types. - -- !!!TODO: Need to perform this check for the TyThing of type functions, - -- too. - tcIdxTyInstDeclTL ldecl@(L loc decl) = - do { tything <- tcFamInstDecl ldecl - ; setSrcSpan loc $ - when (isAssocFamily tything) $ - addErr $ assocInClassErr (tcdName decl) - ; return tything - } - isAssocFamily (ATyCon tycon) = - case tyConFamInst_maybe tycon of - Nothing -> panic "isAssocFamily: no family?!?" - Just (fam, _) -> isTyConAssoc fam - isAssocFamily _ = panic "isAssocFamily: no tycon?!?" - -assocInClassErr :: Name -> SDoc -assocInClassErr name = - ptext (sLit "Associated type") <+> quotes (ppr name) <+> - ptext (sLit "must be inside a class instance") addInsts :: [InstInfo Name] -> TcM a -> TcM a addInsts infos thing_inside @@ -414,7 +393,8 @@ tcLocalInstDecl1 (L loc (InstDecl poly_ty binds uprags ats)) -- Next, process any associated types. ; idx_tycons <- recoverM (return []) $ - do { idx_tycons <- checkNoErrs $ mapAndRecoverM tcFamInstDecl ats + do { idx_tycons <- checkNoErrs $ + mapAndRecoverM (tcFamInstDecl NotTopLevel) ats ; checkValidAndMissingATs clas (tyvars, inst_tys) (zip ats idx_tycons) ; return idx_tycons } @@ -541,7 +521,7 @@ tcLocalInstDecl1 (L loc (InstDecl poly_ty binds uprags ats)) \begin{code} tcInstDecls2 :: [LTyClDecl Name] -> [InstInfo Name] - -> TcM (LHsBinds Id, TcLclEnv) + -> TcM (LHsBinds Id) -- (a) From each class declaration, -- generate any default-method bindings -- (b) From each instance decl @@ -550,18 +530,18 @@ tcInstDecls2 :: [LTyClDecl Name] -> [InstInfo Name] tcInstDecls2 tycl_decls inst_decls = do { -- (a) Default methods from class decls let class_decls = filter (isClassDecl . unLoc) tycl_decls - ; (dm_ids_s, dm_binds_s) <- mapAndUnzipM tcClassDecl2 class_decls + ; dm_binds_s <- mapM tcClassDecl2 class_decls + ; let dm_binds = unionManyBags dm_binds_s - ; tcExtendIdEnv (concat dm_ids_s) $ do - -- (b) instance declarations - { inst_binds_s <- mapM tcInstDecl2 inst_decls + ; let dm_ids = collectHsBindsBinders dm_binds + -- Add the default method Ids (again) + -- See Note [Default methods and instances] + ; inst_binds_s <- tcExtendIdEnv dm_ids $ + mapM tcInstDecl2 inst_decls -- Done - ; let binds = unionManyBags dm_binds_s `unionBags` - unionManyBags inst_binds_s - ; tcl_env <- getLclEnv -- Default method Ids in here - ; return (binds, tcl_env) } } + ; return (dm_binds `unionBags` unionManyBags inst_binds_s) } tcInstDecl2 :: InstInfo Name -> TcM (LHsBinds Id) tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = ibinds }) @@ -574,6 +554,18 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = ibinds }) loc = getSrcSpan dfun_id \end{code} +See Note [Default methods and instances] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The default method Ids are already in the type environment (see Note +[Default method Ids and Template Haskell] in TcTyClsDcls), BUT they +don't have their InlinePragmas yet. Usually that would not matter, +because the simplifier propagates information from binding site to +use. But, unusually, when compiling instance decls we *copy* the +INLINE pragma from the default method to the method for that +particular operation (see Note [INLINE and default methods] below). + +So right here in tcInstDecl2 we must re-extend the type envt with +the default method Ids replete with their INLINE pragmas. Urk. \begin{code} tc_inst_decl2 :: Id -> InstBindings Name -> TcM (LHsBinds Id) @@ -705,9 +697,9 @@ tc_inst_decl2 dfun_id (NewTypeDerived coi _) -- Ordinary instances tc_inst_decl2 dfun_id (VanillaInst monobinds uprags standalone_deriv) - = do { let rigid_info = InstSkol - inst_ty = idType dfun_id - loc = getSrcSpan dfun_id + = do { let rigid_info = InstSkol + inst_ty = idType dfun_id + loc = getSrcSpan dfun_id -- Instantiate the instance decl with skolem constants ; (inst_tyvars', dfun_theta', inst_head') <- tcSkolSigType rigid_info inst_ty @@ -774,7 +766,8 @@ tc_inst_decl2 dfun_id (VanillaInst monobinds uprags standalone_deriv) ; let dict_constr = classDataCon clas this_dict_id = instToId this_dict dict_bind = mkVarBind this_dict_id dict_rhs - dict_rhs = foldl mk_app inst_constr (sc_ids ++ meth_ids) + dict_rhs = foldl mk_app inst_constr sc_meth_ids + sc_meth_ids = sc_ids ++ meth_ids inst_constr = L loc $ wrapId (mkWpTyApps inst_tys') (dataConWrapId dict_constr) -- We don't produce a binding for the dict_constr; instead we @@ -792,7 +785,7 @@ tc_inst_decl2 dfun_id (VanillaInst monobinds uprags standalone_deriv) -- See Note [ClassOp/DFun selection] -- See also note [Single-method classes] dfun_id_w_fun = dfun_id - `setIdUnfolding` mkDFunUnfolding dict_constr (sc_ids ++ meth_ids) + `setIdUnfolding` mkDFunUnfolding inst_ty (map Var sc_meth_ids) `setInlinePragma` dfunInlinePragma main_bind = AbsBinds @@ -1004,13 +997,14 @@ tcInstanceMethod loc standalone_deriv clas tyvars dfun_dicts inst_tys = add_meth_ctxt rn_bind $ do { (meth_id1, spec_prags) <- tcPrags NonRecursive False True meth_id (prag_fn sel_name) - ; tcInstanceMethodBody (instLoc this_dict) + ; bind <- tcInstanceMethodBody (instLoc this_dict) tyvars dfun_dicts ([this_dict], this_dict_bind) meth_id1 local_meth_id meth_sig_fn (SpecPrags (spec_inst_prags ++ spec_prags)) - rn_bind } + rn_bind + ; return (meth_id1, bind) } -------------- tc_default :: DefMeth -> TcM (Id, LHsBind Id) @@ -1026,7 +1020,7 @@ tcInstanceMethod loc standalone_deriv clas tyvars dfun_dicts inst_tys = do { meth_bind <- mkGenericDefMethBind clas inst_tys sel_id local_meth_name ; tc_body meth_bind } - tc_default DefMeth -- An polymorphic default method + tc_default (DefMeth dm_name) -- An polymorphic default method = do { -- Build the typechecked version directly, -- without calling typecheck_method; -- see Note [Default methods in instances] @@ -1034,8 +1028,7 @@ tcInstanceMethod loc standalone_deriv clas tyvars dfun_dicts inst_tys -- in $dm inst_tys this -- The 'let' is necessary only because HsSyn doesn't allow -- you to apply a function to a dictionary *expression*. - dm_name <- lookupGlobalOccRn (mkDefMethRdrName sel_name) - -- Might not be imported, but will be an OrigName + ; dm_id <- tcLookupId dm_name ; let dm_inline_prag = idInlinePragma dm_id rhs = HsWrap (WpApp (instToId this_dict) <.> mkWpTyApps inst_tys) $