X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcDeriv.lhs;h=dd422ae1ff5ea46c36891fc1b0b673fa3475c7e8;hb=a6c7e7dc8d0c5626ea29c71c3fc957d33064697b;hp=39f6968df40f6efa179640b67266f52e8b789964;hpb=26741ec416bae2c502ef00a2ba0e79050a32cb67;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcDeriv.lhs b/ghc/compiler/typecheck/TcDeriv.lhs index 39f6968..dd422ae 100644 --- a/ghc/compiler/typecheck/TcDeriv.lhs +++ b/ghc/compiler/typecheck/TcDeriv.lhs @@ -12,56 +12,62 @@ module TcDeriv ( tcDeriving ) where IMP_Ubiq() -import HsSyn ( FixityDecl, Sig, HsBinds(..), Bind(..), MonoBinds(..), +import HsSyn ( HsDecl, FixityDecl, Fixity, InstDecl, + Sig, HsBinds(..), MonoBinds(..), GRHSsAndBinds, Match, HsExpr, HsLit, InPat, - ArithSeqInfo, Fake, MonoType ) + ArithSeqInfo, Fake, HsType, + collectMonoBinders + ) import HsPragmas ( InstancePragmas(..) ) -import RnHsSyn ( mkRnName, RnName(..), RenamedHsBinds(..), RenamedFixityDecl(..) ) -import TcHsSyn ( TcIdOcc ) +import RdrHsSyn ( RdrName, SYN_IE(RdrNameMonoBinds) ) +import RnHsSyn ( SYN_IE(RenamedHsBinds), SYN_IE(RenamedMonoBinds), SYN_IE(RenamedFixityDecl) ) import TcMonad -import Inst ( InstanceMapper(..) ) +import Inst ( SYN_IE(InstanceMapper) ) import TcEnv ( getEnv_TyCons, tcLookupClassByKey ) +import SpecEnv ( SpecEnv ) import TcKind ( TcKind ) import TcGenDeriv -- Deriv stuff import TcInstUtil ( InstInfo(..), mkInstanceRelatedIds, buildInstanceEnvs ) import TcSimplify ( tcSimplifyThetas ) +import TcType ( TcIdOcc ) -import RnMonad -import RnUtils ( SYN_IE(RnEnv), extendGlobalRnEnv ) -import RnBinds ( rnMethodBinds, rnTopBinds ) +import RnBinds ( rnMethodBinds, rnTopMonoBinds ) +import RnEnv ( newDfunName, bindLocatedLocalsRn ) +import RnMonad ( SYN_IE(RnM), RnDown, GDown, SDown, RnNameSupply(..), + setNameSupplyRn, renameSourceCode, thenRn, mapRn, returnRn ) -import Bag ( emptyBag{-ToDo:rm-}, Bag, isEmptyBag, unionBags, listToBag ) -import Class ( classKey, needsDataDeclCtxtClassKeys, GenClass ) -import ErrUtils ( pprBagOfErrors, addErrLoc, SYN_IE(Error) ) +import Bag ( Bag, emptyBag, isEmptyBag, unionBags, listToBag ) +import Class ( classKey, GenClass, SYN_IE(Class) ) +import ErrUtils ( addErrLoc, SYN_IE(Error) ) import Id ( dataConArgTys, isNullaryDataCon, mkDictFunId ) +import PrelInfo ( needsDataDeclCtxtClassKeys ) import Maybes ( maybeToBool ) -import Name ( isLocallyDefined, getSrcLoc, - mkTopLevName, origName, mkImplicitName, ExportFlag(..), - RdrName(..), Name{--O only-} +import Name ( isLocallyDefined, getSrcLoc, ExportFlag(..), Provenance, + Name{--O only-}, SYN_IE(Module), NamedThing(..) ) -import Outputable ( Outputable(..){-instances e.g., (,)-} ) +import Outputable ( PprStyle(..), Outputable(..){-instances e.g., (,)-} ) import PprType ( GenType, GenTyVar, GenClass, TyCon ) -import PprStyle ( PprStyle(..) ) -import Pretty ( ppAbove, ppAboves, ppCat, ppBesides, ppStr, ppHang, SYN_IE(Pretty) ) -import Pretty--ToDo:rm -import FiniteMap--ToDo:rm +import Pretty ( ($$), vcat, hsep, hcat, parens, empty, (<+>), + ptext, char, hang, Doc ) import SrcLoc ( mkGeneratedSrcLoc, SrcLoc ) import TyCon ( tyConTyVars, tyConDataCons, tyConDerivings, - tyConTheta, maybeTyConSingleCon, - isEnumerationTyCon, isDataTyCon, TyCon + tyConTheta, maybeTyConSingleCon, isDataTyCon, + isEnumerationTyCon, isAlgTyCon, TyCon ) import Type ( GenType(..), SYN_IE(TauType), mkTyVarTys, applyTyCon, mkSigmaTy, mkDictTy, isPrimType, instantiateTy, getAppDataTyCon, getAppTyCon ) import TysPrim ( voidTy ) -import TyVar ( GenTyVar ) +import TyVar ( GenTyVar, SYN_IE(TyVar) ) import UniqFM ( emptyUFM ) import Unique -- Keys stuff +import Bag ( bagToList ) import Util ( zipWithEqual, zipEqual, sortLt, removeDups, assoc, - thenCmp, cmpList, panic, pprPanic, pprPanic#, - assertPanic, pprTrace{-ToDo:rm-} + thenCmp, cmpList, panic, panic#, pprPanic, pprPanic#, + Ord3(..), assertPanic-- , pprTrace{-ToDo:rm-} + ) \end{code} @@ -193,24 +199,24 @@ context to the instance decl. The "offending classes" are \begin{code} tcDeriving :: Module -- name of module under scrutiny - -> RnEnv -- for "renaming" bits of generated code + -> RnNameSupply -- for "renaming" bits of generated code -> Bag InstInfo -- What we already know about instances - -> [RenamedFixityDecl] -- Fixity info; used by Read and Show -> TcM s (Bag InstInfo, -- The generated "instance decls". RenamedHsBinds, -- Extra generated bindings - PprStyle -> Pretty) -- Printable derived instance decls; + PprStyle -> Doc) -- Printable derived instance decls; -- for debugging via -ddump-derivings. -tcDeriving modname rn_env inst_decl_infos_in fixities - = -- Fish the "deriving"-related information out of the TcEnv +tcDeriving modname rn_name_supply inst_decl_infos_in + = recoverTc (returnTc (emptyBag, EmptyBinds, \_ -> empty)) $ + + -- Fish the "deriving"-related information out of the TcEnv -- and make the necessary "equations". - makeDerivEqns `thenTc` \ eqns -> + makeDerivEqns `thenTc` \ eqns -> -- Take the equation list and solve it, to deliver a list of -- solutions, a.k.a. the contexts for the instance decls -- required for the corresponding equations. - solveDerivEqns inst_decl_infos_in eqns - `thenTc` \ new_inst_infos -> + solveDerivEqns inst_decl_infos_in eqns `thenTc` \ new_inst_infos -> -- Now augment the InstInfos, adding in the rather boring -- actual-code-to-do-the-methods binds. We may also need to @@ -218,28 +224,47 @@ tcDeriving modname rn_env inst_decl_infos_in fixities -- "con2tag" and/or "tag2con" functions. We do these -- separately. - gen_taggery_Names new_inst_infos `thenTc` \ nm_alist_etc -> - gen_tag_n_con_binds rn_env nm_alist_etc - `thenTc` \ (extra_binds, deriver_rn_env) -> + gen_taggery_Names new_inst_infos `thenTc` \ nm_alist_etc -> + - mapTc (gen_inst_info modname fixities deriver_rn_env) new_inst_infos - `thenTc` \ really_new_inst_infos -> let - ddump_deriv = ddump_deriving really_new_inst_infos extra_binds + extra_mbind_list = map gen_tag_n_con_monobind nm_alist_etc + extra_mbinds = foldr AndMonoBinds EmptyMonoBinds extra_mbind_list + method_binds_s = map gen_bind new_inst_infos + mbinders = bagToList (collectMonoBinders extra_mbinds) + + -- Rename to get RenamedBinds. + -- The only tricky bit is that the extra_binds must scope over the + -- method bindings for the instances. + (dfun_names_w_method_binds, rn_extra_binds) + = renameSourceCode modname rn_name_supply ( + bindLocatedLocalsRn (\_ -> ptext (SLIT("deriving"))) mbinders $ \ _ -> + rnTopMonoBinds extra_mbinds [] `thenRn` \ rn_extra_binds -> + mapRn rn_one method_binds_s `thenRn` \ dfun_names_w_method_binds -> + returnRn (dfun_names_w_method_binds, rn_extra_binds) + ) + rn_one meth_binds = newDfunName Nothing mkGeneratedSrcLoc `thenRn` \ dfun_name -> + rnMethodBinds meth_binds `thenRn` \ rn_meth_binds -> + returnRn (dfun_name, rn_meth_binds) + + really_new_inst_infos = map (gen_inst_info modname) + (new_inst_infos `zip` dfun_names_w_method_binds) + + ddump_deriv = ddump_deriving really_new_inst_infos rn_extra_binds in --pprTrace "derived:\n" (ddump_deriv PprDebug) $ returnTc (listToBag really_new_inst_infos, - extra_binds, + rn_extra_binds, ddump_deriv) where - ddump_deriving :: [InstInfo] -> RenamedHsBinds -> (PprStyle -> Pretty) + ddump_deriving :: [InstInfo] -> RenamedHsBinds -> (PprStyle -> Doc) ddump_deriving inst_infos extra_binds sty - = ppAboves ((map pp_info inst_infos) ++ [ppr sty extra_binds]) + = vcat ((map pp_info inst_infos) ++ [ppr sty extra_binds]) where - pp_info (InstInfo clas tvs ty inst_decl_theta _ _ _ mbinds _ _ _ _) - = ppAbove (ppr sty (mkSigmaTy tvs inst_decl_theta (mkDictTy clas ty))) + pp_info (InstInfo clas tvs ty inst_decl_theta _ _ mbinds _ _) + = ($$) (ppr sty (mkSigmaTy tvs inst_decl_theta (mkDictTy clas ty))) (ppr sty mbinds) \end{code} @@ -270,17 +295,21 @@ makeDerivEqns :: TcM s [DerivEqn] makeDerivEqns = tcGetEnv `thenNF_Tc` \ env -> - tcLookupClassByKey evalClassKey `thenNF_Tc` \ eval_clas -> let - tycons = filter isDataTyCon (getEnv_TyCons env) - -- ToDo: what about newtypes??? - think_about_deriving = need_deriving eval_clas tycons + local_data_tycons = filter (\tc -> isLocallyDefined tc && isAlgTyCon tc) + (getEnv_TyCons env) in - mapTc chk_out think_about_deriving `thenTc_` + if null local_data_tycons then + -- Bale out now; evalClass may not be loaded if there aren't any + returnTc [] + else + tcLookupClassByKey evalClassKey `thenNF_Tc` \ eval_clas -> let - (derive_these, _) = removeDups cmp_deriv think_about_deriving - eqns = map mk_eqn derive_these + think_about_deriving = need_deriving eval_clas local_data_tycons + (derive_these, _) = removeDups cmp_deriv think_about_deriving + eqns = map mk_eqn derive_these in + mapTc chk_out think_about_deriving `thenTc_` returnTc eqns where ------------------------------------------------------------------ @@ -312,20 +341,24 @@ makeDerivEqns is_enumeration = isEnumerationTyCon tycon is_single_con = maybeToBool (maybeTyConSingleCon tycon) - chk_clas clas_uniq clas_str cond + single_nullary_why = SLIT("one constructor data type or type with all nullary constructors expected") + nullary_why = SLIT("data type with all nullary constructors expected") + + chk_clas clas_uniq clas_str clas_why cond = if (clas_uniq == clas_key) - then checkTc cond (derivingThingErr clas_str tycon) + then checkTc cond (derivingThingErr clas_str clas_why tycon) else returnTc () in -- Are things OK for deriving Enum (if appropriate)? - chk_clas enumClassKey "Enum" is_enumeration `thenTc_` + chk_clas enumClassKey (SLIT("Enum")) nullary_why is_enumeration `thenTc_` -- Are things OK for deriving Bounded (if appropriate)? - chk_clas boundedClassKey "Bounded" - (is_enumeration || is_single_con) `thenTc_` + chk_clas boundedClassKey (SLIT("Bounded")) single_nullary_why + (is_enumeration || is_single_con) `thenTc_` -- Are things OK for deriving Ix (if appropriate)? - chk_clas ixClassKey "Ix.Ix" (is_enumeration || is_single_con) + chk_clas ixClassKey (SLIT("Ix.Ix")) single_nullary_why + (is_enumeration || is_single_con) ------------------------------------------------------------------ cmp_deriv :: (Class, TyCon) -> (Class, TyCon) -> TAG_ @@ -400,45 +433,50 @@ solveDerivEqns inst_decl_infos_in orig_eqns initial_solutions :: [DerivSoln] initial_solutions = [ [] | _ <- orig_eqns ] + ------------------------------------------------------------------ -- iterateDeriv calculates the next batch of solutions, -- compares it with the current one; finishes if they are the -- same, otherwise recurses with the new solutions. - + -- It fails if any iteration fails iterateDeriv :: [DerivSoln] ->TcM s [InstInfo] - iterateDeriv current_solns + = checkNoErrsTc (iterateOnce current_solns) `thenTc` \ (new_inst_infos, new_solns) -> + if (current_solns `eq_solns` new_solns) then + returnTc new_inst_infos + else + iterateDeriv new_solns + + ------------------------------------------------------------------ + iterateOnce current_solns = -- Extend the inst info from the explicit instance decls -- with the current set of solutions, giving a add_solns inst_decl_infos_in orig_eqns current_solns `thenTc` \ (new_inst_infos, inst_mapper) -> let - class_to_inst_env cls = fst (inst_mapper cls) + class_to_inst_env cls = inst_mapper cls in -- Simplify each RHS - listTc [ tcSimplifyThetas class_to_inst_env [{-Nothing "given"-}] deriv_rhs - | (_,_,_,deriv_rhs) <- orig_eqns ] `thenTc` \ next_solns -> + listTc [ tcAddErrCtxt (derivCtxt tc) $ + tcSimplifyThetas class_to_inst_env [{-Nothing "given"-}] deriv_rhs + | (_,tc,_,deriv_rhs) <- orig_eqns ] `thenTc` \ next_solns -> -- Canonicalise the solutions, so they compare nicely let canonicalised_next_solns - = [ sortLt lt_rhs next_soln | next_soln <- next_solns ] in - - if (current_solns `eq_solns` canonicalised_next_solns) then - returnTc new_inst_infos - else - iterateDeriv canonicalised_next_solns + = [ sortLt lt_rhs next_soln | next_soln <- next_solns ] + in + returnTc (new_inst_infos, canonicalised_next_solns) - where - ------------------------------------------------------------------ - lt_rhs r1 r2 = case cmp_rhs r1 r2 of { LT_ -> True; _ -> False } - eq_solns s1 s2 = case cmp_solns s1 s2 of { EQ_ -> True; _ -> False } - cmp_solns s1 s2 = cmpList (cmpList cmp_rhs) s1 s2 - cmp_rhs (c1, TyVarTy tv1) (c2, TyVarTy tv2) + ------------------------------------------------------------------ + lt_rhs r1 r2 = case cmp_rhs r1 r2 of { LT_ -> True; _ -> False } + eq_solns s1 s2 = case cmp_solns s1 s2 of { EQ_ -> True; _ -> False } + cmp_solns s1 s2 = cmpList (cmpList cmp_rhs) s1 s2 + cmp_rhs (c1, TyVarTy tv1) (c2, TyVarTy tv2) = (tv1 `cmp` tv2) `thenCmp` (c1 `cmp` c2) #ifdef DEBUG - cmp_rhs other_1 other_2 - = pprPanic# "tcDeriv:cmp_rhs:" (ppCat [ppr PprDebug other_1, ppr PprDebug other_2]) + cmp_rhs other_1 other_2 + = panic# "tcDeriv:cmp_rhs:" --(hsep [ppr PprDebug other_1, ppr PprDebug other_2]) #endif \end{code} @@ -452,7 +490,16 @@ add_solns :: Bag InstInfo -- The global, non-derived ones -- because we need the LHS info for addClassInstance. add_solns inst_infos_in eqns solns - = buildInstanceEnvs all_inst_infos `thenTc` \ inst_mapper -> + +-- ------------------ +-- OLD: checkErrsTc above now deals with this +-- = discardErrsTc (buildInstanceEnvs all_inst_infos `thenTc` \ inst_mapper -> + -- We do the discard-errs so that we don't get repeated error messages + -- about duplicate instances. + -- They'll appear later, when we do the top-level buildInstanceEnvs. +-- ------------------ + + = buildInstanceEnvs all_inst_infos `thenTc` \ inst_mapper -> returnTc (new_inst_infos, inst_mapper) where new_inst_infos = zipWithEqual "add_solns" mk_deriv_inst_info eqns solns @@ -466,14 +513,12 @@ add_solns inst_infos_in eqns solns dummy_dfun_id - (my_panic "const_meth_ids") - (my_panic "binds") (my_panic "from_here") - (my_panic "modname") mkGeneratedSrcLoc + (my_panic "binds") (getSrcLoc tycon) (my_panic "upragmas") where dummy_dfun_id - = mkDictFunId bottom bottom bottom dummy_dfun_ty - bottom bottom bottom bottom + = mkDictFunId (getName tycon) dummy_dfun_ty bottom bottom + -- The name is getSrcLoc'd in an error message where bottom = panic "dummy_dfun_id" @@ -489,7 +534,7 @@ add_solns inst_infos_in eqns solns -- We can't leave it as a panic because to get the theta part we -- have to run down the type! - my_panic str = pprPanic ("add_soln:"++str) (ppCat [ppChar ':', ppr PprDebug clas, ppr PprDebug tycon]) + my_panic str = panic "add_soln" -- pprPanic ("add_soln:"++str) (hsep [char ':', ppr PprDebug clas, ppr PprDebug tycon]) \end{code} %************************************************************************ @@ -555,142 +600,65 @@ the renamer. What a great hack! \end{itemize} \begin{code} -gen_inst_info :: Module -- Module name - -> [RenamedFixityDecl] -- all known fixities; - -- may be needed for Text - -> RnEnv -- lookup stuff for names we may use - -> InstInfo -- the main stuff to work on - -> TcM s InstInfo -- the gen'd (filled-in) "instance decl" - -gen_inst_info modname fixities deriver_rn_env - (InstInfo clas tyvars ty inst_decl_theta _ _ _ _ _ _ locn _) +-- Generate the method bindings for the required instance +gen_bind :: InstInfo -> RdrNameMonoBinds +gen_bind (InstInfo clas _ ty _ _ _ _ _ _) + | not from_here + = EmptyMonoBinds + | otherwise + = assoc "gen_inst_info:bad derived class" + [(eqClassKey, gen_Eq_binds) + ,(ordClassKey, gen_Ord_binds) + ,(enumClassKey, gen_Enum_binds) + ,(evalClassKey, gen_Eval_binds) + ,(boundedClassKey, gen_Bounded_binds) + ,(showClassKey, gen_Show_binds) + ,(readClassKey, gen_Read_binds) + ,(ixClassKey, gen_Ix_binds) + ] + (classKey clas) + tycon + where + from_here = isLocallyDefined tycon + (tycon,_,_) = getAppDataTyCon ty + + +gen_inst_info :: Module -- Module name + -> (InstInfo, (Name, RenamedMonoBinds)) -- the main stuff to work on + -> InstInfo -- the gen'd (filled-in) "instance decl" + +gen_inst_info modname + (InstInfo clas tyvars ty inst_decl_theta _ _ _ locn _, (dfun_name, meth_binds)) = -- Generate the various instance-related Ids - mkInstanceRelatedIds - True {-from_here-} locn modname - NoInstancePragmas - clas tyvars ty - inst_decl_theta - [{-no user pragmas-}] - `thenTc` \ (dfun_id, dfun_theta, const_meth_ids) -> - - -- Generate the bindings for the new instance declaration, - -- rename it, and check for errors - let - (tycon,_,_) = --pprTrace "gen_inst_info:ty" (ppCat[ppr PprDebug clas, ppr PprDebug ty]) $ - getAppDataTyCon ty - - proto_mbinds - = assoc "gen_inst_info:bad derived class" - [(eqClassKey, gen_Eq_binds) - ,(ordClassKey, gen_Ord_binds) - ,(enumClassKey, gen_Enum_binds) - ,(evalClassKey, gen_Eval_binds) - ,(boundedClassKey, gen_Bounded_binds) - ,(showClassKey, gen_Show_binds fixities) - ,(readClassKey, gen_Read_binds fixities) - ,(ixClassKey, gen_Ix_binds) - ] - clas_key $ tycon - in -{- - let - ((qual, unqual, tc_qual, tc_unqual), stack) = deriver_rn_env - in - pprTrace "gen_inst:qual:" (ppCat [ppBesides[ppPStr m,ppChar '.',ppPStr n] | (n,m) <- keysFM qual]) $ - pprTrace "gen_inst:unqual:" (ppCat (map ppPStr (keysFM unqual))) $ - pprTrace "gen_inst:tc_qual:" (ppCat [ppBesides[ppPStr m,ppChar '.',ppPStr n] | (n,m) <- keysFM tc_qual]) $ - pprTrace "gen_inst:tc_unqual:" (ppCat (map ppPStr (keysFM tc_unqual))) $ --} - -- pprTrace "derived binds:" (ppr PprDebug proto_mbinds) $ - - rnMtoTcM deriver_rn_env ( - setExtraRn emptyUFM{-no fixities-} $ - rnMethodBinds clas_Name proto_mbinds - ) `thenNF_Tc` \ (mbinds, errs) -> - - if not (isEmptyBag errs) then - pprPanic "gen_inst_info:renamer errs!\n" - (ppAbove (pprBagOfErrors PprDebug errs) (ppr PprDebug proto_mbinds)) - else - -- All done - let - from_here = isLocallyDefined tycon -- If so, then from here - in - returnTc (InstInfo clas tyvars ty inst_decl_theta - dfun_theta dfun_id const_meth_ids - (if from_here then mbinds else EmptyMonoBinds) - from_here modname locn []) + InstInfo clas tyvars ty inst_decl_theta + dfun_theta dfun_id + meth_binds + locn [] where - clas_key = classKey clas - clas_Name = RnImplicitClass (mkImplicitName clas_key (origName "gen_inst_info" clas)) + (dfun_id, dfun_theta) = mkInstanceRelatedIds + dfun_name + clas tyvars ty + inst_decl_theta + + from_here = isLocallyDefined tycon + (tycon,_,_) = getAppDataTyCon ty \end{code} + %************************************************************************ %* * -\subsection[TcGenDeriv-con2tag-tag2con]{Generating extra binds (@con2tag@ and @tag2con@)} +\subsection[TcDeriv-taggery-Names]{What con2tag/tag2con functions are available?} %* * %************************************************************************ + data Foo ... = ... con2tag_Foo :: Foo ... -> Int# tag2con_Foo :: Int -> Foo ... -- easier if Int, not Int# maxtag_Foo :: Int -- ditto (NB: not unboxed) -\begin{code} -gen_tag_n_con_binds :: RnEnv - -> [(RdrName, TyCon, TagThingWanted)] - -> TcM s (RenamedHsBinds, - RnEnv) -- input one with any new names added - -gen_tag_n_con_binds rn_env nm_alist_etc - = - let - -- We have the renamer's final "name funs" in our hands - -- (they were passed in). So we can handle ProtoNames - -- that refer to anything "out there". But our generated - -- code may also mention "con2tag" (etc.). So we need - -- to augment to "name funs" to include those. - - names_to_add = [ pn | (pn,_,_) <- nm_alist_etc ] - in - tcGetUniques (length names_to_add) `thenNF_Tc` \ uniqs -> - let - pairs_to_add = [ case pn of { Qual pnm pnn -> - (pn, mkRnName (mkTopLevName u (OrigName pnm pnn) mkGeneratedSrcLoc ExportAll [])) } - | (pn,u) <- zipEqual "gen_tag..." names_to_add uniqs ] - - deriver_rn_env - = if null names_to_add - then rn_env else added_rn_env - - (added_rn_env, errs_bag) - = extendGlobalRnEnv rn_env pairs_to_add [{-no tycons-}] - - ---------------- - proto_mbind_list = map gen_tag_n_con_monobind nm_alist_etc - proto_mbinds = foldr AndMonoBinds EmptyMonoBinds proto_mbind_list - in - ASSERT(isEmptyBag errs_bag) - - rnMtoTcM deriver_rn_env ( - setExtraRn emptyUFM{-no fixities-} $ - rnTopBinds (SingleBind (RecBind proto_mbinds)) - ) `thenNF_Tc` \ (binds, errs) -> - - if not (isEmptyBag errs) then - pprPanic "gen_tag_n_con_binds:renamer errs!\n" - (ppAbove (pprBagOfErrors PprDebug errs) (ppr PprDebug binds)) - else - returnTc (binds, deriver_rn_env) -\end{code} - -%************************************************************************ -%* * -\subsection[TcDeriv-taggery-Names]{What con2tag/tag2con functions are available?} -%* * -%************************************************************************ We have a @con2tag@ function for a tycon if: \begin{itemize} @@ -717,11 +685,11 @@ gen_taggery_Names :: [InstInfo] TagThingWanted)] gen_taggery_Names inst_infos - = --pprTrace "gen_taggery:\n" (ppAboves [ppCat [ppr PprDebug c, ppr PprDebug t] | (c,t) <- all_CTs]) $ + = --pprTrace "gen_taggery:\n" (vcat [hsep [ppr PprDebug c, ppr PprDebug t] | (c,t) <- all_CTs]) $ foldlTc do_con2tag [] tycons_of_interest `thenTc` \ names_so_far -> foldlTc do_tag2con names_so_far tycons_of_interest where - all_CTs = [ mk_CT c ty | (InstInfo c _ ty _ _ _ _ _ _ _ _ _) <- inst_infos ] + all_CTs = [ mk_CT c ty | (InstInfo c _ ty _ _ _ _ _ _) <- inst_infos ] mk_CT c ty = (c, fst (getAppTyCon ty)) @@ -729,24 +697,25 @@ gen_taggery_Names inst_infos (tycons_of_interest, _) = removeDups cmp all_tycons do_con2tag acc_Names tycon - = if (we_are_deriving eqClassKey tycon + | isDataTyCon tycon && + (we_are_deriving eqClassKey tycon && any isNullaryDataCon (tyConDataCons tycon)) - || (we_are_deriving ordClassKey tycon + || (we_are_deriving ordClassKey tycon && not (maybeToBool (maybeTyConSingleCon tycon))) - || (we_are_deriving enumClassKey tycon) - || (we_are_deriving ixClassKey tycon) - then - returnTc ((con2tag_PN tycon, tycon, GenCon2Tag) + || (we_are_deriving enumClassKey tycon) + || (we_are_deriving ixClassKey tycon) + + = returnTc ((con2tag_RDR tycon, tycon, GenCon2Tag) : acc_Names) - else - returnTc acc_Names + | otherwise + = returnTc acc_Names do_tag2con acc_Names tycon = if (we_are_deriving enumClassKey tycon) || (we_are_deriving ixClassKey tycon) then - returnTc ( (tag2con_PN tycon, tycon, GenTag2Con) - : (maxtag_PN tycon, tycon, GenMaxTag) + returnTc ( (tag2con_RDR tycon, tycon, GenTag2Con) + : (maxtag_RDR tycon, tycon, GenMaxTag) : acc_Names) else returnTc acc_Names @@ -762,9 +731,13 @@ gen_taggery_Names inst_infos \end{code} \begin{code} -derivingThingErr :: String -> TyCon -> Error +derivingThingErr :: FAST_STRING -> FAST_STRING -> TyCon -> Error + +derivingThingErr thing why tycon sty + = hang (hsep [ptext SLIT("Can't make a derived instance of"), ptext thing]) + 0 (hang (hsep [ptext SLIT("for the type"), ppr sty tycon]) + 0 (parens (ptext why))) -derivingThingErr thing tycon sty - = ppHang (ppCat [ppStr "Can't make a derived instance of", ppStr thing]) - 4 (ppBesides [ppStr "for the type `", ppr sty tycon, ppStr "'"]) +derivCtxt tycon sty + = ptext SLIT("When deriving classes for") <+> ppr sty tycon \end{code}