X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcClassDcl.lhs;h=4890ec95d22ce7548e09f9618453b1edcc695925;hb=79011516105291b58324ce71a87f6bb26a131090;hp=9fb530de5959f5fa6279759f1d9ea94b058fa826;hpb=202ac08f3e2afde0620e889cc81a95b2fd0ad9e1;p=ghc-hetmet.git diff --git a/compiler/typecheck/TcClassDcl.lhs b/compiler/typecheck/TcClassDcl.lhs index 9fb530d..4890ec9 100644 --- a/compiler/typecheck/TcClassDcl.lhs +++ b/compiler/typecheck/TcClassDcl.lhs @@ -1,70 +1,68 @@ % +% (c) The University of Glasgow 2006 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % -\section[TcClassDcl]{Typechecking class declarations} + +Typechecking class declarations \begin{code} +{-# OPTIONS -w #-} +-- The above warning supression flag is a temporary kludge. +-- While working on this module you are encouraged to remove it and fix +-- any warnings in the module. See +-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings +-- for details + module TcClassDcl ( tcClassSigs, tcClassDecl2, getGenericInstances, MethodSpec, tcMethodBind, mkMethodBind, - tcAddDeclCtxt, badMethodErr + tcAddDeclCtxt, badMethodErr, badATErr, omittedATWarn ) where #include "HsVersions.h" import HsSyn -import RnHsSyn ( maybeGenericMatch, extractHsTyVars ) -import RnExpr ( rnLExpr ) -import RnEnv ( lookupTopBndrRn, lookupImportedName ) -import Inst ( instToId, newDictBndr, newDictBndrs, newMethod, getOverlapFlag ) -import InstEnv ( mkLocalInstance ) -import TcEnv ( tcLookupLocatedClass, - tcExtendTyVarEnv, tcExtendIdEnv, - InstInfo(..), pprInstInfoDetails, - simpleInstInfoTyCon, simpleInstInfoTy, - InstBindings(..), newDFunName - ) -import TcBinds ( TcPragFun, tcMonoBinds, tcPrags, mkPragFun, TcSigInfo(..), - TcSigFun, mkTcSigFun ) -import TcHsType ( tcHsKindedType, tcHsSigType ) -import TcSimplify ( tcSimplifyCheck ) -import TcUnify ( checkSigTyVars, sigCtxt ) -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 - ) +import RnHsSyn +import RnExpr +import RnEnv +import Inst +import InstEnv +import TcEnv +import TcBinds +import TcHsType +import TcSimplify +import TcUnify +import TcMType +import TcType import TcRnMonad -import Generics ( mkGenericRhs, validGenericInstanceType ) -import PrelInfo ( nO_METHOD_BINDING_ERROR_ID ) -import Class ( classTyVars, classBigSig, - Class, ClassOpItem, DefMeth (..) ) -import TyCon ( TyCon, tyConName, tyConHasGenerics ) -import Type ( substTyWith ) -import MkId ( mkDefaultMethodId, mkDictFunId ) -import Id ( Id, idType, idName, mkUserLocal ) -import Name ( Name, NamedThing(..) ) -import NameEnv ( NameEnv, lookupNameEnv, mkNameEnv ) -import NameSet ( nameSetToList ) -import OccName ( reportIfUnused, mkDefaultMethodOcc ) -import RdrName ( RdrName, mkDerivedRdrName ) +import Generics +import PrelInfo +import Class +import TyCon +import Type +import MkId +import Id +import Name +import NameEnv +import NameSet +import OccName +import RdrName import Outputable -import PrelNames ( genericTyConNames ) +import PrelNames import DynFlags -import ErrUtils ( dumpIfSet_dyn ) -import Util ( count, lengthIs, isSingleton, lengthExceeds ) -import Unique ( Uniquable(..) ) -import ListSetOps ( equivClassesByUniq, minusList ) -import SrcLoc ( Located(..), srcSpanStart, unLoc, noLoc ) -import Maybes ( seqMaybe, isJust, mapCatMaybes ) -import List ( partition ) -import BasicTypes ( RecFlag(..), Boxity(..) ) +import ErrUtils +import Util +import Unique +import ListSetOps +import SrcLoc +import Maybes +import List +import BasicTypes import Bag import FastString -\end{code} +import Control.Monad +\end{code} Dictionary handling @@ -116,7 +114,7 @@ type TcMethInfo = (Name, DefMeth, Type) -- A temporary intermediate, to communic -- between tcClassSigs and buildClass tcClassSigs clas sigs def_methods = do { dm_env <- checkDefaultBinds clas op_names def_methods - ; mappM (tcClassSig dm_env) op_sigs } + ; mapM (tcClassSig dm_env) op_sigs } where op_sigs = [sig | sig@(L _ (TypeSig _ _)) <- sigs] op_names = [n | sig@(L _ (TypeSig (L _ n) _)) <- op_sigs] @@ -139,7 +137,7 @@ checkDefaultBind clas ops (FunBind {fun_id = L _ op, fun_matches = MatchGroup ma -- Check that all the defns ar generic, or none are ; checkTc (all_generic || none_generic) (mixedGenericErr op) - ; returnM (op, all_generic) + ; return (op, all_generic) } where n_generic = count (isJust . maybeGenericMatch) matches @@ -158,7 +156,7 @@ tcClassSig dm_env (L loc (TypeSig (L _ op_name) op_hs_ty)) Nothing -> NoDefMeth Just False -> DefMeth Just True -> GenDefMeth - ; returnM (op_name, dm, op_ty) } + ; return (op_name, dm, op_ty) } \end{code} @@ -232,9 +230,9 @@ tcClassDecl2 :: LTyClDecl Name -- The class declaration tcClassDecl2 (L loc (ClassDecl {tcdLName = class_name, tcdSigs = sigs, tcdMeths = default_binds})) - = recoverM (returnM (emptyLHsBinds, [])) $ - setSrcSpan loc $ - tcLookupLocatedClass class_name `thenM` \ clas -> + = recoverM (return (emptyLHsBinds, [])) $ + setSrcSpan loc $ do + clas <- tcLookupLocatedClass class_name -- We make a separate binding for each default method. -- At one time I used a single AbsBinds for all of them, thus @@ -261,9 +259,9 @@ tcClassDecl2 (L loc (ClassDecl {tcdLName = class_name, tcdSigs = sigs, -- default method for every class op, regardless of whether or not -- the programmer supplied an explicit default decl for the class. -- (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 (listToBag defm_binds, concat dm_ids_s) + + (defm_binds, dm_ids_s) <- mapAndUnzipM tc_dm dm_sel_ids + return (listToBag defm_binds, concat dm_ids_s) tcDefMeth origin clas tyvars binds_in sig_fn prag_fn sel_id = do { dm_name <- lookupTopBndrRn (mkDefMethRdrName sel_id) @@ -282,7 +280,7 @@ tcDefMeth origin clas tyvars binds_in sig_fn prag_fn sel_id -- Check the context { dict_binds <- tcSimplifyCheck - (ptext SLIT("class") <+> ppr clas) + loc tyvars [this_dict] insts_needed @@ -303,7 +301,7 @@ tcDefMeth origin clas tyvars binds_in sig_fn prag_fn sel_id [instToId this_dict] [(tyvars, local_dm_id, dm_inst_id, prags)] (dict_binds `unionBags` defm_bind) - ; returnM (noLoc full_bind, [local_dm_id]) }} + ; return (noLoc full_bind, [local_dm_id]) }} mkDefMethRdrName :: Id -> RdrName mkDefMethRdrName sel_id = mkDerivedRdrName (idName sel_id) mkDefaultMethodOcc @@ -343,7 +341,7 @@ tcMethodBind tcMethodBind inst_tyvars inst_theta avail_insts sig_fn prag_fn (sel_id, meth_id, meth_bind) - = recoverM (returnM emptyLHsBinds) $ + = recoverM (return emptyLHsBinds) $ do -- 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 @@ -355,13 +353,13 @@ tcMethodBind inst_tyvars inst_theta avail_insts sig_fn prag_fn let sel_name = idName sel_id meth_sig_fn meth_name = ASSERT( meth_name == idName meth_id ) sig_fn sel_name -- The meth_bind metions the meth_name, but sig_fn is indexed by sel_name - in - tcExtendTyVarEnv inst_tyvars ( - tcExtendIdEnv [meth_id] $ -- In scope for tcInstSig - addErrCtxt (methodCtxt sel_id) $ - getLIE $ - tcMonoBinds [meth_bind] meth_sig_fn Recursive - ) `thenM` \ ((meth_bind, mono_bind_infos), meth_lie) -> + + ((meth_bind, mono_bind_infos), meth_lie) + <- tcExtendTyVarEnv inst_tyvars $ + tcExtendIdEnv [meth_id] $ -- In scope for tcInstSig + addErrCtxt (methodCtxt sel_id) $ + getLIE $ + tcMonoBinds [meth_bind] meth_sig_fn Recursive -- Now do context reduction. We simplify wrt both the local tyvars -- and the ones of the class/instance decl, so that there is @@ -373,29 +371,27 @@ tcMethodBind inst_tyvars inst_theta avail_insts sig_fn prag_fn let [(_, Just sig, local_meth_id)] = mono_bind_infos - in + loc = sig_loc sig - addErrCtxtM (sigCtxt sel_id inst_tyvars inst_theta (idType meth_id)) $ - newDictBndrs (sig_loc sig) (sig_theta sig) `thenM` \ meth_dicts -> - let + addErrCtxtM (sigCtxt sel_id inst_tyvars inst_theta (idType meth_id)) $ do + meth_dicts <- newDictBndrs loc (sig_theta sig) + let meth_tvs = sig_tvs sig all_tyvars = meth_tvs ++ inst_tyvars all_insts = avail_insts ++ meth_dicts - 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_` + lie_binds <- tcSimplifyCheck loc all_tyvars all_insts meth_lie - tcPrags meth_id (prag_fn sel_name) `thenM` \ prags -> - let + checkSigTyVars all_tyvars + + prags <- tcPrags meth_id (prag_fn sel_name) + let poly_meth_bind = noLoc $ AbsBinds meth_tvs (map instToId meth_dicts) [(meth_tvs, meth_id, local_meth_id, prags)] (lie_binds `unionBags` meth_bind) - in - returnM (unitBag poly_meth_bind) + + return (unitBag poly_meth_bind) mkMethodBind :: InstOrigin @@ -407,23 +403,23 @@ mkMethodBind :: InstOrigin -- Find the binding for the specified method, or make -- up a suitable default method if it isn't there -mkMethodBind origin clas inst_tys meth_binds (sel_id, dm_info) - = mkMethId origin clas sel_id inst_tys `thenM` \ (mb_inst, meth_id) -> +mkMethodBind origin clas inst_tys meth_binds (sel_id, dm_info) = do + (mb_inst, meth_id) <- mkMethId origin clas sel_id inst_tys let meth_name = idName meth_id - in + -- Figure out what method binding to use -- If the user suppplied one, use it, else construct a default one - 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 -> - -- Not infix decl - returnM (noLoc $ mkFunBind (noLoc meth_name) [mkSimpleMatch [] rhs]) - ) `thenM` \ meth_bind -> + loc <- getSrcSpanM + meth_bind + <- case find_bind (idName sel_id) meth_name meth_binds of + Just user_bind -> return user_bind + Nothing -> do + rhs <- mkDefMethRhs origin clas inst_tys sel_id loc dm_info + -- Not infix decl + return (noLoc $ mkFunBind (noLoc meth_name) [mkSimpleMatch [] rhs]) - returnM (mb_inst, (sel_id, meth_id, meth_bind)) + return (mb_inst, (sel_id, meth_id, meth_bind)) mkMethId :: InstOrigin -> Class -> Id -> [TcType] -- Selector, and instance types @@ -436,7 +432,7 @@ mkMethId origin clas sel_id inst_tys rho_ty = ASSERT( length tyvars == length inst_tys ) substTyWith tyvars inst_tys rho (preds,tau) = tcSplitPhiTy rho_ty - first_pred = head preds + first_pred = ASSERT( not (null preds)) head preds in -- The first predicate should be of form (C a b) -- where C is the class in question @@ -444,12 +440,12 @@ mkMethId origin clas sel_id inst_tys case getClassPredTys_maybe first_pred of { Just (clas1,tys) -> clas == clas1 ; Nothing -> False } ) - if isSingleton preds then + if isSingleton preds then do -- If it's the only one, make a 'method' - getInstLoc origin `thenM` \ inst_loc -> - newMethod inst_loc sel_id inst_tys `thenM` \ meth_inst -> - returnM (Just meth_inst, instToId meth_inst) - else + inst_loc <- getInstLoc origin + meth_inst <- newMethod inst_loc sel_id inst_tys + return (Just meth_inst, instToId meth_inst) + else do -- If it's not the only one we need to be careful -- For example, given 'op' defined thus: -- class Foo a where @@ -459,34 +455,33 @@ mkMethId origin clas sel_id inst_tys -- That is, the class-op's context is still there. -- 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 -> - getSrcSpanM `thenM` \ loc -> + uniq <- newUnique + loc <- getSrcSpanM let real_tau = mkPhiTy (tail preds) tau - meth_id = mkUserLocal (getOccName sel_id) uniq real_tau - (srcSpanStart loc) --TODO - in - returnM (Nothing, meth_id) + meth_id = mkUserLocal (getOccName sel_id) uniq real_tau loc + + return (Nothing, meth_id) -- The user didn't supply a method binding, -- so we have to make up a default binding -- The RHS of a default method depends on the default-method info -mkDefMethRhs origin clas inst_tys sel_id loc DefMeth - = -- An polymorphic default method - lookupImportedName (mkDefMethRdrName sel_id) `thenM` \ dm_name -> +mkDefMethRhs origin clas inst_tys sel_id loc DefMeth = do + -- An polymorphic default method + dm_name <- lookupImportedName (mkDefMethRdrName sel_id) -- Might not be imported, but will be an OrigName - traceRn (text "mkDefMeth" <+> ppr dm_name) `thenM_` - returnM (nlHsVar dm_name) + traceRn (text "mkDefMeth" <+> ppr dm_name) + return (nlHsVar dm_name) -mkDefMethRhs origin clas inst_tys sel_id loc NoDefMeth - = -- No default method +mkDefMethRhs origin clas inst_tys sel_id loc NoDefMeth = do + -- No default method -- Warn only if -fwarn-missing-methods - doptM Opt_WarnMissingMethods `thenM` \ warn -> + warn <- doptM Opt_WarnMissingMethods warnTc (isInstDecl origin && warn && reportIfUnused (getOccName sel_id)) - (omittedMethodWarn sel_id) `thenM_` - returnM error_rhs + (omittedMethodWarn sel_id) + return error_rhs where error_rhs = noLoc $ HsLam (mkMatchGroup [mkSimpleMatch wild_pats simple_rhs]) simple_rhs = nlHsApp (nlHsVar (getName nO_METHOD_BINDING_ERROR_ID)) @@ -526,13 +521,13 @@ mkDefMethRhs origin clas inst_tys sel_id loc GenDefMeth (badGenericInstance sel_id (notGeneric tycon)) ; dflags <- getDOpts - ; ioToTcRn (dumpIfSet_dyn dflags Opt_D_dump_deriv "Filling in method body" + ; liftIO (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 } + ; return rn_rhs } where rhs = mkGenericRhs sel_id clas_tyvar tycon @@ -540,7 +535,7 @@ mkDefMethRhs origin clas inst_tys sel_id loc GenDefMeth -- case we require that the instance decl is for a single-parameter -- type class with type variable arguments: -- instance (...) => C (T a b) - clas_tyvar = head (classTyVars clas) + clas_tyvar = ASSERT (not (null (classTyVars clas))) head (classTyVars clas) Just tycon = maybe_tycon maybe_tycon = case inst_tys of [ty] -> case tcSplitTyConApp_maybe ty of @@ -548,8 +543,8 @@ mkDefMethRhs origin clas inst_tys sel_id loc GenDefMeth other -> Nothing other -> Nothing -isInstDecl (SigOrigin (InstSkol _)) = True -isInstDecl (SigOrigin (ClsSkol _)) = False +isInstDecl (SigOrigin InstSkol) = True +isInstDecl (SigOrigin (ClsSkol _)) = False \end{code} @@ -557,7 +552,7 @@ isInstDecl (SigOrigin (ClsSkol _)) = False -- 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 binds - = foldlBag seqMaybe Nothing (mapBag f binds) + = foldlBag mplus Nothing (mapBag f binds) where 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 })) @@ -598,40 +593,42 @@ gives rise to the instance declarations \begin{code} getGenericInstances :: [LTyClDecl Name] -> TcM [InstInfo] getGenericInstances class_decls - = do { gen_inst_infos <- mappM (addLocM get_generics) class_decls + = do { gen_inst_infos <- mapM (addLocM get_generics) class_decls ; let { gen_inst_info = concat gen_inst_infos } -- Return right away if there is no generic stuff - ; if null gen_inst_info then returnM [] + ; if null gen_inst_info then return [] else do -- Otherwise print it out { dflags <- getDOpts - ; ioToTcRn (dumpIfSet_dyn dflags Opt_D_dump_deriv "Generic instances" - (vcat (map pprInstInfoDetails gen_inst_info))) - ; returnM gen_inst_info }} + ; liftIO (dumpIfSet_dyn dflags Opt_D_dump_deriv "Generic instances" + (vcat (map pprInstInfoDetails gen_inst_info))) + ; return gen_inst_info }} get_generics decl@(ClassDecl {tcdLName = class_name, tcdMeths = def_methods}) | null generic_binds - = returnM [] -- The comon case: no generic default methods + = return [] -- The comon case: no generic default methods | otherwise -- A source class decl with generic default methods - = recoverM (returnM []) $ - tcAddDeclCtxt decl $ - tcLookupLocatedClass class_name `thenM` \ clas -> + = recoverM (return []) $ + tcAddDeclCtxt decl $ do + clas <- tcLookupLocatedClass class_name -- Group by type, and -- make an InstInfo out of each group let groups = groupWith listToBag generic_binds - in - mappM (mkGenericInstance clas) groups `thenM` \ inst_infos -> + + inst_infos <- mapM (mkGenericInstance clas) groups -- Check that there is only one InstInfo for each type constructor -- The main way this can fail is if you write -- f {| a+b |} ... = ... -- f {| x+y |} ... = ... -- Then at this point we'll have an InstInfo for each + -- + -- The class should be unary, which is why simpleInstInfoTyCon should be ok let tc_inst_infos :: [(TyCon, InstInfo)] tc_inst_infos = [(simpleInstInfoTyCon i, i) | i <- inst_infos] @@ -639,16 +636,16 @@ get_generics decl@(ClassDecl {tcdLName = class_name, tcdMeths = def_methods}) bad_groups = [group | group <- equivClassesByUniq get_uniq tc_inst_infos, group `lengthExceeds` 1] get_uniq (tc,_) = getUnique tc - in - mappM (addErrTc . dupGenericInsts) bad_groups `thenM_` + + mapM (addErrTc . dupGenericInsts) bad_groups -- Check that there is an InstInfo for each generic type constructor let missing = genericTyConNames `minusList` [tyConName tc | (tc,_) <- tc_inst_infos] - in - checkTc (null missing) (missingGenericInstances missing) `thenM_` - returnM inst_infos + checkTc (null missing) (missingGenericInstances missing) + + return inst_infos where generic_binds :: [(HsType Name, LHsBind Name)] generic_binds = getGenericBinds def_methods @@ -694,35 +691,35 @@ mkGenericInstance :: Class -> (HsType Name, LHsBinds Name) -> TcM InstInfo -mkGenericInstance clas (hs_ty, binds) +mkGenericInstance clas (hs_ty, binds) = do -- Make a generic instance declaration -- For example: instance (C a, C b) => C (a+b) where { binds } - = -- Extract the universally quantified type variables + -- Extract the universally quantified type variables -- and wrap them as forall'd tyvars, so that kind inference -- works in the standard way let 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 -> + forall_inst_ty <- tcHsSigType GenPatCtxt hs_forall_ty let (tyvars, inst_ty) = tcSplitForAllTys forall_inst_ty - in + checkTc (validGenericInstanceType inst_ty) - (badGenericInstanceType binds) `thenM_` + (badGenericInstanceType binds) -- Make the dictionary function. - getSrcSpanM `thenM` \ span -> - getOverlapFlag `thenM` \ overlap_flag -> - newDFunName clas [inst_ty] (srcSpanStart span) `thenM` \ dfun_name -> + span <- getSrcSpanM + overlap_flag <- getOverlapFlag + dfun_name <- newDFunName clas [inst_ty] span 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 { iSpec = ispec, iBinds = VanillaInst binds [] }) + + return (InstInfo { iSpec = ispec, iBinds = VanillaInst binds [] }) \end{code} @@ -736,60 +733,67 @@ mkGenericInstance clas (hs_ty, binds) tcAddDeclCtxt decl thing_inside = addErrCtxt ctxt thing_inside where - thing = case decl of - ClassDecl {} -> "class" - TySynonym {} -> "type synonym" - TyFunction {} -> "type function signature" - TyData {tcdND = NewType} -> "newtype" ++ maybeSig - TyData {tcdND = DataType} -> "data type" ++ maybeSig + thing | isClassDecl decl = "class" + | isTypeDecl decl = "type synonym" ++ maybeInst + | isDataDecl decl = if tcdND decl == NewType + then "newtype" ++ maybeInst + else "data type" ++ maybeInst + | isFamilyDecl decl = "family" - maybeSig | isKindSigDecl decl = " signature" - | otherwise = "" + maybeInst | isFamInstDecl decl = " instance" + | otherwise = "" - ctxt = hsep [ptext SLIT("In the"), text thing, - ptext SLIT("declaration for"), quotes (ppr (tcdName decl))] + ctxt = hsep [ptext (sLit "In the"), text thing, + ptext (sLit "declaration for"), quotes (ppr (tcdName decl))] defltMethCtxt clas - = ptext SLIT("When checking the default methods for class") <+> quotes (ppr clas) + = ptext (sLit "When checking the default methods for class") <+> quotes (ppr clas) methodCtxt sel_id - = ptext SLIT("In the definition for method") <+> quotes (ppr sel_id) + = ptext (sLit "In the definition for method") <+> quotes (ppr sel_id) badMethodErr clas op - = hsep [ptext SLIT("Class"), quotes (ppr clas), - ptext SLIT("does not have a method"), quotes (ppr op)] + = hsep [ptext (sLit "Class"), quotes (ppr clas), + ptext (sLit "does not have a method"), quotes (ppr op)] + +badATErr clas at + = hsep [ptext (sLit "Class"), quotes (ppr clas), + ptext (sLit "does not have an associated type"), quotes (ppr at)] omittedMethodWarn sel_id - = ptext SLIT("No explicit method nor default method for") <+> quotes (ppr sel_id) + = ptext (sLit "No explicit method nor default method for") <+> quotes (ppr sel_id) + +omittedATWarn at + = ptext (sLit "No explicit AT declaration for") <+> quotes (ppr at) badGenericInstance sel_id because - = sep [ptext SLIT("Can't derive generic code for") <+> quotes (ppr sel_id), + = sep [ptext (sLit "Can't derive generic code for") <+> quotes (ppr sel_id), because] notSimple inst_tys - = vcat [ptext SLIT("because the instance type(s)"), + = vcat [ptext (sLit "because the instance type(s)"), nest 2 (ppr inst_tys), - ptext SLIT("is not a simple type of form (T a b c)")] + ptext (sLit "is not a simple type of form (T a1 ... an)")] notGeneric tycon - = vcat [ptext SLIT("because the instance type constructor") <+> quotes (ppr tycon) <+> - ptext SLIT("was not compiled with -fgenerics")] + = vcat [ptext (sLit "because the instance type constructor") <+> quotes (ppr tycon) <+> + ptext (sLit "was not compiled with -fgenerics")] badGenericInstanceType binds - = vcat [ptext SLIT("Illegal type pattern in the generic bindings"), + = vcat [ptext (sLit "Illegal type pattern in the generic bindings"), nest 4 (ppr binds)] missingGenericInstances missing - = ptext SLIT("Missing type patterns for") <+> pprQuotedList missing + = ptext (sLit "Missing type patterns for") <+> pprQuotedList missing dupGenericInsts tc_inst_infos - = vcat [ptext SLIT("More than one type pattern for a single generic type constructor:"), + = vcat [ptext (sLit "More than one type pattern for a single generic type constructor:"), nest 4 (vcat (map ppr_inst_ty tc_inst_infos)), - ptext SLIT("All the type patterns for a generic type constructor must be identical") + ptext (sLit "All the type patterns for a generic type constructor must be identical") ] where 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) + = ptext (sLit "Can't mix generic and non-generic equations for class method") <+> quotes (ppr op) \end{code}