src/HOL/Codatatype/Tools/bnf_fp_sugar.ML
author blanchet
Mon, 17 Sep 2012 21:13:30 +0200
changeset 50444 64ac3471005a
parent 50442 b017e1dbc77c
child 50449 433dc7e028c8
permissions -rw-r--r--
cleaner way of dealing with the set functions of sums and products
     1 (*  Title:      HOL/Codatatype/Tools/bnf_fp_sugar.ML
     2     Author:     Jasmin Blanchette, TU Muenchen
     3     Copyright   2012
     4 
     5 Sugared datatype and codatatype constructions.
     6 *)
     7 
     8 signature BNF_FP_SUGAR =
     9 sig
    10   val datatyp: bool ->
    11     (mixfix list -> (string * sort) list option -> binding list -> typ list * typ list list ->
    12       BNF_Def.BNF list -> local_theory ->
    13       (term list * term list * term list * term list * thm * thm list * thm list * thm list *
    14          thm list * thm list) * local_theory) ->
    15     bool * ((((typ * sort) list * binding) * mixfix) * ((((binding * binding) *
    16       (binding * typ) list) * (binding * term) list) * mixfix) list) list ->
    17     local_theory -> local_theory
    18   val parse_datatype_cmd: bool ->
    19     (mixfix list -> (string * sort) list option -> binding list -> typ list * typ list list ->
    20       BNF_Def.BNF list -> local_theory ->
    21       (term list * term list * term list * term list * thm * thm list * thm list * thm list *
    22          thm list * thm list) * local_theory) ->
    23     (local_theory -> local_theory) parser
    24 end;
    25 
    26 structure BNF_FP_Sugar : BNF_FP_SUGAR =
    27 struct
    28 
    29 open BNF_Util
    30 open BNF_Wrap
    31 open BNF_Def
    32 open BNF_FP_Util
    33 open BNF_FP_Sugar_Tactics
    34 
    35 val simp_attrs = @{attributes [simp]};
    36 
    37 fun split_list10 xs =
    38   (map #1 xs, map #2 xs, map #3 xs, map #4 xs, map #5 xs, map #6 xs, map #7 xs, map #8 xs,
    39    map #9 xs, map #10 xs);
    40 
    41 fun resort_tfree S (TFree (s, _)) = TFree (s, S);
    42 
    43 fun typ_subst inst (T as Type (s, Ts)) =
    44     (case AList.lookup (op =) inst T of
    45       NONE => Type (s, map (typ_subst inst) Ts)
    46     | SOME T' => T')
    47   | typ_subst inst T = the_default T (AList.lookup (op =) inst T);
    48 
    49 val lists_bmoc = fold (fn xs => fn t => Term.list_comb (t, xs));
    50 
    51 fun mk_tupled_fun x f xs = HOLogic.tupled_lambda x (Term.list_comb (f, xs));
    52 fun mk_uncurried_fun f xs = mk_tupled_fun (HOLogic.mk_tuple xs) f xs;
    53 fun mk_uncurried2_fun f xss =
    54   mk_tupled_fun (HOLogic.mk_tuple (map HOLogic.mk_tuple xss)) f (flat xss);
    55 
    56 fun tick v f = Term.lambda v (HOLogic.mk_prod (v, f $ v));
    57 
    58 fun tack z_name (c, v) f =
    59   let val z = Free (z_name, mk_sumT (fastype_of v, fastype_of c)) in
    60     Term.lambda z (mk_sum_case (Term.lambda v v, Term.lambda c (f $ c)) $ z)
    61   end;
    62 
    63 fun cannot_merge_types () = error "Mutually recursive types must have the same type parameters";
    64 
    65 fun merge_type_arg T T' = if T = T' then T else cannot_merge_types ();
    66 
    67 fun merge_type_args (As, As') =
    68   if length As = length As' then map2 merge_type_arg As As' else cannot_merge_types ();
    69 
    70 fun type_args_constrained_of (((cAs, _), _), _) = cAs;
    71 fun type_binding_of (((_, b), _), _) = b;
    72 fun mixfix_of ((_, mx), _) = mx;
    73 fun ctr_specs_of (_, ctr_specs) = ctr_specs;
    74 
    75 fun disc_of ((((disc, _), _), _), _) = disc;
    76 fun ctr_of ((((_, ctr), _), _), _) = ctr;
    77 fun args_of (((_, args), _), _) = args;
    78 fun defaults_of ((_, ds), _) = ds;
    79 fun ctr_mixfix_of (_, mx) = mx;
    80 
    81 fun define_datatype prepare_constraint prepare_typ prepare_term lfp construct (no_dests, specs)
    82     no_defs_lthy0 =
    83   let
    84     (* TODO: sanity checks on arguments *)
    85 
    86     val _ = if not lfp andalso no_dests then error "Cannot define destructor-less codatatypes"
    87       else ();
    88 
    89     val nn = length specs;
    90     val fp_bs = map type_binding_of specs;
    91     val fp_common_name = mk_common_name fp_bs;
    92 
    93     fun prepare_type_arg (ty, c) =
    94       let val TFree (s, _) = prepare_typ no_defs_lthy0 ty in
    95         TFree (s, prepare_constraint no_defs_lthy0 c)
    96       end;
    97 
    98     val Ass0 = map (map prepare_type_arg o type_args_constrained_of) specs;
    99     val unsorted_Ass0 = map (map (resort_tfree HOLogic.typeS)) Ass0;
   100     val unsorted_As = Library.foldr1 merge_type_args unsorted_Ass0;
   101 
   102     val ((Bs, Cs), no_defs_lthy) =
   103       no_defs_lthy0
   104       |> fold (Variable.declare_typ o resort_tfree dummyS) unsorted_As
   105       |> mk_TFrees nn
   106       ||>> mk_TFrees nn;
   107 
   108     (* TODO: cleaner handling of fake contexts, without "background_theory" *)
   109     (*the "perhaps o try" below helps gracefully handles the case where the new type is defined in a
   110       locale and shadows an existing global type*)
   111     val fake_thy =
   112       Theory.copy #> fold (fn spec => perhaps (try (Sign.add_type no_defs_lthy
   113         (type_binding_of spec, length (type_args_constrained_of spec), mixfix_of spec)))) specs;
   114     val fake_lthy = Proof_Context.background_theory fake_thy no_defs_lthy;
   115 
   116     fun mk_fake_T b =
   117       Type (fst (Term.dest_Type (Proof_Context.read_type_name fake_lthy true (Binding.name_of b))),
   118         unsorted_As);
   119 
   120     val fake_Ts = map mk_fake_T fp_bs;
   121 
   122     val mixfixes = map mixfix_of specs;
   123 
   124     val _ = (case duplicates Binding.eq_name fp_bs of [] => ()
   125       | b :: _ => error ("Duplicate type name declaration " ^ quote (Binding.name_of b)));
   126 
   127     val ctr_specss = map ctr_specs_of specs;
   128 
   129     val disc_bindingss = map (map disc_of) ctr_specss;
   130     val ctr_bindingss =
   131       map2 (fn fp_b => map (Binding.qualify false (Binding.name_of fp_b) o ctr_of))
   132         fp_bs ctr_specss;
   133     val ctr_argsss = map (map args_of) ctr_specss;
   134     val ctr_mixfixess = map (map ctr_mixfix_of) ctr_specss;
   135 
   136     val sel_bindingsss = map (map (map fst)) ctr_argsss;
   137     val fake_ctr_Tsss0 = map (map (map (prepare_typ fake_lthy o snd))) ctr_argsss;
   138     val raw_sel_defaultsss = map (map defaults_of) ctr_specss;
   139 
   140     val (As :: _) :: fake_ctr_Tsss =
   141       burrow (burrow (Syntax.check_typs fake_lthy)) (Ass0 :: fake_ctr_Tsss0);
   142 
   143     val _ = (case duplicates (op =) unsorted_As of [] => ()
   144       | A :: _ => error ("Duplicate type parameter " ^
   145           quote (Syntax.string_of_typ no_defs_lthy A)));
   146 
   147     val rhs_As' = fold (fold (fold Term.add_tfreesT)) fake_ctr_Tsss [];
   148     val _ = (case subtract (op =) (map dest_TFree As) rhs_As' of
   149         [] => ()
   150       | A' :: _ => error ("Extra type variable on right-hand side: " ^
   151           quote (Syntax.string_of_typ no_defs_lthy (TFree A'))));
   152 
   153     fun eq_fpT (T as Type (s, Us)) (Type (s', Us')) =
   154         s = s' andalso (Us = Us' orelse error ("Illegal occurrence of recursive type " ^
   155           quote (Syntax.string_of_typ fake_lthy T)))
   156       | eq_fpT _ _ = false;
   157 
   158     fun freeze_fp (T as Type (s, Us)) =
   159         (case find_index (eq_fpT T) fake_Ts of ~1 => Type (s, map freeze_fp Us) | j => nth Bs j)
   160       | freeze_fp T = T;
   161 
   162     val ctr_TsssBs = map (map (map freeze_fp)) fake_ctr_Tsss;
   163     val ctr_sum_prod_TsBs = map (mk_sumTN_balanced o map HOLogic.mk_tupleT) ctr_TsssBs;
   164 
   165     val fp_eqs =
   166       map dest_TFree Bs ~~ map (Term.typ_subst_atomic (As ~~ unsorted_As)) ctr_sum_prod_TsBs;
   167 
   168     val (pre_bnfs, ((unfs0, flds0, fp_iters0, fp_recs0, fp_induct, unf_flds, fld_unfs, fld_injects,
   169         fp_iter_thms, fp_rec_thms), lthy)) =
   170       fp_bnf construct fp_bs mixfixes (map dest_TFree unsorted_As) fp_eqs no_defs_lthy0;
   171 
   172     fun add_nesty_bnf_names Us =
   173       let
   174         fun add (Type (s, Ts)) ss =
   175             let val (needs, ss') = fold_map add Ts ss in
   176               if exists I needs then (true, insert (op =) s ss') else (false, ss')
   177             end
   178           | add T ss = (member (op =) Us T, ss);
   179       in snd oo add end;
   180 
   181     fun nesty_bnfs Us =
   182       map_filter (bnf_of lthy) (fold (fold (fold (add_nesty_bnf_names Us))) ctr_TsssBs []);
   183 
   184     val nesting_bnfs = nesty_bnfs As;
   185     val nested_bnfs = nesty_bnfs Bs;
   186 
   187     val timer = time (Timer.startRealTimer ());
   188 
   189     fun mk_unf_or_fld get_T Ts t =
   190       let val Type (_, Ts0) = get_T (fastype_of t) in
   191         Term.subst_atomic_types (Ts0 ~~ Ts) t
   192       end;
   193 
   194     val mk_unf = mk_unf_or_fld domain_type;
   195     val mk_fld = mk_unf_or_fld range_type;
   196 
   197     val unfs = map (mk_unf As) unfs0;
   198     val flds = map (mk_fld As) flds0;
   199 
   200     val fpTs = map (domain_type o fastype_of) unfs;
   201 
   202     val exists_fp_subtype = exists_subtype (member (op =) fpTs);
   203 
   204     val ctr_Tsss = map (map (map (Term.typ_subst_atomic (Bs ~~ fpTs)))) ctr_TsssBs;
   205     val ns = map length ctr_Tsss;
   206     val kss = map (fn n => 1 upto n) ns;
   207     val mss = map (map length) ctr_Tsss;
   208     val Css = map2 replicate ns Cs;
   209 
   210     fun mk_iter_like Ts Us t =
   211       let
   212         val (bindings, body) = strip_type (fastype_of t);
   213         val (f_Us, prebody) = split_last bindings;
   214         val Type (_, Ts0) = if lfp then prebody else body;
   215         val Us0 = distinct (op =) (map (if lfp then body_type else domain_type) f_Us);
   216       in
   217         Term.subst_atomic_types (Ts0 @ Us0 ~~ Ts @ Us) t
   218       end;
   219 
   220     val fp_iters as fp_iter1 :: _ = map (mk_iter_like As Cs) fp_iters0;
   221     val fp_recs as fp_rec1 :: _ = map (mk_iter_like As Cs) fp_recs0;
   222 
   223     val fp_iter_fun_Ts = fst (split_last (binder_types (fastype_of fp_iter1)));
   224     val fp_rec_fun_Ts = fst (split_last (binder_types (fastype_of fp_rec1)));
   225 
   226     val ((iter_only as (gss, _, _), rec_only as (hss, _, _)),
   227          (zs, cs, cpss, coiter_only as ((pgss, crgsss), _), corec_only as ((phss, cshsss), _))) =
   228       if lfp then
   229         let
   230           val y_Tsss =
   231             map3 (fn n => fn ms => map2 dest_tupleT ms o dest_sumTN_balanced n o domain_type)
   232               ns mss fp_iter_fun_Ts;
   233           val g_Tss = map2 (map2 (curry (op --->))) y_Tsss Css;
   234 
   235           val ((gss, ysss), _) =
   236             lthy
   237             |> mk_Freess "f" g_Tss
   238             ||>> mk_Freesss "x" y_Tsss;
   239           val yssss = map (map (map single)) ysss;
   240 
   241           fun dest_rec_prodT (T as Type (@{type_name prod}, Us as [_, U])) =
   242               if member (op =) Cs U then Us else [T]
   243             | dest_rec_prodT T = [T];
   244 
   245           val z_Tssss =
   246             map3 (fn n => fn ms => map2 (map dest_rec_prodT oo dest_tupleT) ms o
   247               dest_sumTN_balanced n o domain_type) ns mss fp_rec_fun_Ts;
   248           val h_Tss = map2 (map2 (fold_rev (curry (op --->)))) z_Tssss Css;
   249 
   250           val hss = map2 (map2 retype_free) h_Tss gss;
   251           val zssss_hd = map2 (map2 (map2 (retype_free o hd))) z_Tssss ysss;
   252           val (zssss_tl, _) =
   253             lthy
   254             |> mk_Freessss "y" (map (map (map tl)) z_Tssss);
   255           val zssss = map2 (map2 (map2 cons)) zssss_hd zssss_tl;
   256         in
   257           (((gss, g_Tss, yssss), (hss, h_Tss, zssss)),
   258            ([], [], [], (([], []), ([], [])), (([], []), ([], []))))
   259         end
   260       else
   261         let
   262           (*avoid "'a itself" arguments in coiterators and corecursors*)
   263           val mss' =  map (fn [0] => [1] | ms => ms) mss;
   264 
   265           val p_Tss = map2 (fn n => replicate (Int.max (0, n - 1)) o mk_predT) ns Cs;
   266 
   267           fun zip_predss_getterss qss fss = maps (op @) (qss ~~ fss);
   268 
   269           fun zip_preds_predsss_gettersss [] [qss] [fss] = zip_predss_getterss qss fss
   270             | zip_preds_predsss_gettersss (p :: ps) (qss :: qsss) (fss :: fsss) =
   271               p :: zip_predss_getterss qss fss @ zip_preds_predsss_gettersss ps qsss fsss;
   272 
   273           fun mk_types maybe_dest_sumT fun_Ts =
   274             let
   275               val f_sum_prod_Ts = map range_type fun_Ts;
   276               val f_prod_Tss = map2 dest_sumTN_balanced ns f_sum_prod_Ts;
   277               val f_Tssss =
   278                 map3 (fn C => map2 (map (map (curry (op -->) C) o maybe_dest_sumT) oo dest_tupleT))
   279                   Cs mss' f_prod_Tss;
   280               val q_Tssss =
   281                 map (map (map (fn [_] => [] | [_, C] => [mk_predT (domain_type C)]))) f_Tssss;
   282               val pf_Tss = map3 zip_preds_predsss_gettersss p_Tss q_Tssss f_Tssss;
   283             in (q_Tssss, f_sum_prod_Ts, f_Tssss, pf_Tss) end;
   284 
   285           val (r_Tssss, g_sum_prod_Ts, g_Tssss, pg_Tss) = mk_types single fp_iter_fun_Ts;
   286 
   287           val ((((Free (z, _), cs), pss), gssss), _) =
   288             lthy
   289             |> yield_singleton (mk_Frees "z") dummyT
   290             ||>> mk_Frees "a" Cs
   291             ||>> mk_Freess "p" p_Tss
   292             ||>> mk_Freessss "g" g_Tssss;
   293           val rssss = map (map (map (fn [] => []))) r_Tssss;
   294 
   295           fun dest_corec_sumT (T as Type (@{type_name sum}, Us as [_, U])) =
   296               if member (op =) Cs U then Us else [T]
   297             | dest_corec_sumT T = [T];
   298 
   299           val (s_Tssss, h_sum_prod_Ts, h_Tssss, ph_Tss) = mk_types dest_corec_sumT fp_rec_fun_Ts;
   300 
   301           val hssss_hd = map2 (map2 (map2 (fn T :: _ => fn [g] => retype_free T g))) h_Tssss gssss;
   302           val ((sssss, hssss_tl), _) =
   303             lthy
   304             |> mk_Freessss "q" s_Tssss
   305             ||>> mk_Freessss "h" (map (map (map tl)) h_Tssss);
   306           val hssss = map2 (map2 (map2 cons)) hssss_hd hssss_tl;
   307 
   308           val cpss = map2 (fn c => map (fn p => p $ c)) cs pss;
   309 
   310           fun mk_preds_getters_join [] [cf] = cf
   311             | mk_preds_getters_join [cq] [cf, cf'] =
   312               mk_If cq (mk_Inl (fastype_of cf') cf) (mk_Inr (fastype_of cf) cf');
   313 
   314           fun mk_terms qssss fssss =
   315             let
   316               val pfss = map3 zip_preds_predsss_gettersss pss qssss fssss;
   317               val cqssss = map2 (fn c => map (map (map (fn f => f $ c)))) cs qssss;
   318               val cfssss = map2 (fn c => map (map (map (fn f => f $ c)))) cs fssss;
   319               val cqfsss = map2 (map2 (map2 mk_preds_getters_join)) cqssss cfssss;
   320             in (pfss, cqfsss) end;
   321         in
   322           ((([], [], []), ([], [], [])),
   323            ([z], cs, cpss, (mk_terms rssss gssss, (g_sum_prod_Ts, pg_Tss)),
   324             (mk_terms sssss hssss, (h_sum_prod_Ts, ph_Tss))))
   325         end;
   326 
   327     fun define_ctrs_case_for_type ((((((((((((((((((fp_b, fpT), C), fld), unf), fp_iter), fp_rec),
   328           fld_unf), unf_fld), fld_inject), n), ks), ms), ctr_bindings), ctr_mixfixes), ctr_Tss),
   329         disc_bindings), sel_bindingss), raw_sel_defaultss) no_defs_lthy =
   330       let
   331         val unfT = domain_type (fastype_of fld);
   332         val ctr_prod_Ts = map HOLogic.mk_tupleT ctr_Tss;
   333         val ctr_sum_prod_T = mk_sumTN_balanced ctr_prod_Ts;
   334         val case_Ts = map (fn Ts => Ts ---> C) ctr_Tss;
   335 
   336         val ((((u, fs), xss), v'), _) =
   337           no_defs_lthy
   338           |> yield_singleton (mk_Frees "u") unfT
   339           ||>> mk_Frees "f" case_Ts
   340           ||>> mk_Freess "x" ctr_Tss
   341           ||>> yield_singleton (Variable.variant_fixes) (Binding.name_of fp_b);
   342 
   343         val v = Free (v', fpT);
   344 
   345         val ctr_rhss =
   346           map2 (fn k => fn xs => fold_rev Term.lambda xs (fld $
   347             mk_InN_balanced ctr_sum_prod_T n (HOLogic.mk_tuple xs) k)) ks xss;
   348 
   349         val case_binding = Binding.suffix_name ("_" ^ caseN) fp_b;
   350 
   351         val case_rhs =
   352           fold_rev Term.lambda (fs @ [v])
   353             (mk_sum_caseN_balanced (map2 mk_uncurried_fun fs xss) $ (unf $ v));
   354 
   355         val ((raw_case :: raw_ctrs, raw_case_def :: raw_ctr_defs), (lthy', lthy)) = no_defs_lthy
   356           |> apfst split_list o fold_map3 (fn b => fn mx => fn rhs =>
   357               Local_Theory.define ((b, mx), ((Thm.def_binding b, []), rhs)) #>> apsnd snd)
   358             (case_binding :: ctr_bindings) (NoSyn :: ctr_mixfixes) (case_rhs :: ctr_rhss)
   359           ||> `Local_Theory.restore;
   360 
   361         val phi = Proof_Context.export_morphism lthy lthy';
   362 
   363         val ctr_defs = map (Morphism.thm phi) raw_ctr_defs;
   364         val case_def = Morphism.thm phi raw_case_def;
   365 
   366         val ctrs0 = map (Morphism.term phi) raw_ctrs;
   367         val casex0 = Morphism.term phi raw_case;
   368 
   369         val ctrs = map (mk_ctr As) ctrs0;
   370 
   371         fun exhaust_tac {context = ctxt, ...} =
   372           let
   373             val fld_iff_unf_thm =
   374               let
   375                 val goal =
   376                   fold_rev Logic.all [u, v]
   377                     (mk_Trueprop_eq (HOLogic.mk_eq (v, fld $ u), HOLogic.mk_eq (unf $ v, u)));
   378               in
   379                 Skip_Proof.prove lthy [] [] goal (fn {context = ctxt, ...} =>
   380                   mk_fld_iff_unf_tac ctxt (map (SOME o certifyT lthy) [unfT, fpT])
   381                     (certify lthy fld) (certify lthy unf) fld_unf unf_fld)
   382                 |> Thm.close_derivation
   383                 |> Morphism.thm phi
   384               end;
   385 
   386             val sumEN_thm' =
   387               Local_Defs.unfold lthy @{thms all_unit_eq}
   388                 (Drule.instantiate' (map (SOME o certifyT lthy) ctr_prod_Ts) []
   389                    (mk_sumEN_balanced n))
   390               |> Morphism.thm phi;
   391           in
   392             mk_exhaust_tac ctxt n ctr_defs fld_iff_unf_thm sumEN_thm'
   393           end;
   394 
   395         val inject_tacss =
   396           map2 (fn 0 => K [] | _ => fn ctr_def => [fn {context = ctxt, ...} =>
   397               mk_inject_tac ctxt ctr_def fld_inject]) ms ctr_defs;
   398 
   399         val half_distinct_tacss =
   400           map (map (fn (def, def') => fn {context = ctxt, ...} =>
   401             mk_half_distinct_tac ctxt fld_inject [def, def'])) (mk_half_pairss ctr_defs);
   402 
   403         val case_tacs =
   404           map3 (fn k => fn m => fn ctr_def => fn {context = ctxt, ...} =>
   405             mk_case_tac ctxt n k m case_def ctr_def unf_fld) ks ms ctr_defs;
   406 
   407         val tacss = [exhaust_tac] :: inject_tacss @ half_distinct_tacss @ [case_tacs];
   408 
   409         fun define_iter_rec ((selss0, discIs, sel_thmss), no_defs_lthy) =
   410           let
   411             val fpT_to_C = fpT --> C;
   412 
   413             fun generate_iter_like (suf, fp_iter_like, (fss, f_Tss, xssss)) =
   414               let
   415                 val res_T = fold_rev (curry (op --->)) f_Tss fpT_to_C;
   416                 val binding = Binding.suffix_name ("_" ^ suf) fp_b;
   417                 val spec =
   418                   mk_Trueprop_eq (lists_bmoc fss (Free (Binding.name_of binding, res_T)),
   419                     Term.list_comb (fp_iter_like,
   420                       map2 (mk_sum_caseN_balanced oo map2 mk_uncurried2_fun) fss xssss));
   421               in (binding, spec) end;
   422 
   423             val iter_like_infos =
   424               [(iterN, fp_iter, iter_only),
   425                (recN, fp_rec, rec_only)];
   426 
   427             val (bindings, specs) = map generate_iter_like iter_like_infos |> split_list;
   428 
   429             val ((csts, defs), (lthy', lthy)) = no_defs_lthy
   430               |> apfst split_list o fold_map2 (fn b => fn spec =>
   431                 Specification.definition (SOME (b, NONE, NoSyn), ((Thm.def_binding b, []), spec))
   432                 #>> apsnd snd) bindings specs
   433               ||> `Local_Theory.restore;
   434 
   435             val phi = Proof_Context.export_morphism lthy lthy';
   436 
   437             val [iter_def, rec_def] = map (Morphism.thm phi) defs;
   438 
   439             val [iter, recx] = map (mk_iter_like As Cs o Morphism.term phi) csts;
   440           in
   441             ((ctrs, selss0, iter, recx, xss, ctr_defs, discIs, sel_thmss, iter_def, rec_def), lthy)
   442           end;
   443 
   444         fun define_coiter_corec ((selss0, discIs, sel_thmss), no_defs_lthy) =
   445           let
   446             val B_to_fpT = C --> fpT;
   447 
   448             fun mk_preds_getterss_join c n cps sum_prod_T cqfss =
   449               Term.lambda c (mk_IfN sum_prod_T cps
   450                 (map2 (mk_InN_balanced sum_prod_T n) (map HOLogic.mk_tuple cqfss) (1 upto n)));
   451 
   452             fun generate_coiter_like (suf, fp_iter_like, ((pfss, cqfsss), (f_sum_prod_Ts,
   453                 pf_Tss))) =
   454               let
   455                 val res_T = fold_rev (curry (op --->)) pf_Tss B_to_fpT;
   456                 val binding = Binding.suffix_name ("_" ^ suf) fp_b;
   457                 val spec =
   458                   mk_Trueprop_eq (lists_bmoc pfss (Free (Binding.name_of binding, res_T)),
   459                     Term.list_comb (fp_iter_like,
   460                       map5 mk_preds_getterss_join cs ns cpss f_sum_prod_Ts cqfsss));
   461               in (binding, spec) end;
   462 
   463             val coiter_like_infos =
   464               [(coiterN, fp_iter, coiter_only),
   465                (corecN, fp_rec, corec_only)];
   466 
   467             val (bindings, specs) = map generate_coiter_like coiter_like_infos |> split_list;
   468 
   469             val ((csts, defs), (lthy', lthy)) = no_defs_lthy
   470               |> apfst split_list o fold_map2 (fn b => fn spec =>
   471                 Specification.definition (SOME (b, NONE, NoSyn), ((Thm.def_binding b, []), spec))
   472                 #>> apsnd snd) bindings specs
   473               ||> `Local_Theory.restore;
   474 
   475             val phi = Proof_Context.export_morphism lthy lthy';
   476 
   477             val [coiter_def, corec_def] = map (Morphism.thm phi) defs;
   478 
   479             val [coiter, corec] = map (mk_iter_like As Cs o Morphism.term phi) csts;
   480           in
   481             ((ctrs, selss0, coiter, corec, xss, ctr_defs, discIs, sel_thmss, coiter_def, corec_def),
   482              lthy)
   483           end;
   484 
   485         fun wrap lthy =
   486           let val sel_defaultss = map (map (apsnd (prepare_term lthy))) raw_sel_defaultss in
   487             wrap_datatype tacss (((no_dests, ctrs0), casex0), (disc_bindings, (sel_bindingss,
   488               sel_defaultss))) lthy
   489           end;
   490 
   491         val define_iter_likes = if lfp then define_iter_rec else define_coiter_corec;
   492       in
   493         ((wrap, define_iter_likes), lthy')
   494       end;
   495 
   496     val pre_map_defs = map map_def_of_bnf pre_bnfs;
   497     val pre_set_defss = map set_defs_of_bnf pre_bnfs;
   498     val nested_set_natural's = maps set_natural'_of_bnf nested_bnfs;
   499     val nesting_map_ids = map map_id_of_bnf nesting_bnfs;
   500 
   501     fun mk_map live Ts Us t =
   502       let
   503         val (Type (_, Ts0), Type (_, Us0)) = strip_typeN (live + 1) (fastype_of t) |>> List.last
   504       in
   505         Term.subst_atomic_types (Ts0 @ Us0 ~~ Ts @ Us) t
   506       end;
   507 
   508     fun build_map build_arg (T as Type (s, Ts)) (U as Type (_, Us)) =
   509       let
   510         val bnf = the (bnf_of lthy s);
   511         val live = live_of_bnf bnf;
   512         val mapx = mk_map live Ts Us (map_of_bnf bnf);
   513         val TUs = map dest_funT (fst (strip_typeN live (fastype_of mapx)));
   514         val args = map build_arg TUs;
   515       in Term.list_comb (mapx, args) end;
   516 
   517     fun derive_induct_iter_rec_thms_for_types ((ctrss, _, iters, recs, xsss, ctr_defss, _, _,
   518         iter_defs, rec_defs), lthy) =
   519       let
   520         val (((phis, phis'), vs'), names_lthy) =
   521           lthy
   522           |> mk_Frees' "P" (map mk_predT fpTs)
   523           ||>> Variable.variant_fixes (map Binding.name_of fp_bs);
   524 
   525         val vs = map2 (curry Free) vs' fpTs;
   526 
   527         fun mk_sets_nested bnf =
   528           let
   529             val Type (T_name, Us) = T_of_bnf bnf;
   530             val lives = lives_of_bnf bnf;
   531             val sets = sets_of_bnf bnf;
   532             fun mk_set U =
   533               (case find_index (curry (op =) U) lives of
   534                 ~1 => Term.dummy
   535               | i => nth sets i);
   536           in
   537             (T_name, map mk_set Us)
   538           end;
   539 
   540         val setss_nested = map mk_sets_nested nested_bnfs;
   541 
   542         val (induct_thms, induct_thm) =
   543           let
   544             fun mk_set Ts t =
   545               let val Type (_, Ts0) = domain_type (fastype_of t) in
   546                 Term.subst_atomic_types (Ts0 ~~ Ts) t
   547               end;
   548 
   549             fun mk_raw_prem_prems names_lthy (x as Free (s, T as Type (T_name, Ts0))) =
   550                 (case find_index (curry (op =) T) fpTs of
   551                   ~1 =>
   552                   (case AList.lookup (op =) setss_nested T_name of
   553                     NONE => []
   554                   | SOME raw_sets0 =>
   555                     let
   556                       val (Ts, raw_sets) =
   557                         split_list (filter (exists_fp_subtype o fst) (Ts0 ~~ raw_sets0));
   558                       val sets = map (mk_set Ts0) raw_sets;
   559                       val (ys, names_lthy') = names_lthy |> mk_Frees s Ts;
   560                       val xysets = map (pair x) (ys ~~ sets);
   561                       val ppremss = map (mk_raw_prem_prems names_lthy') ys;
   562                     in
   563                       flat (map2 (map o apfst o cons) xysets ppremss)
   564                     end)
   565                 | i => [([], (i + 1, x))])
   566               | mk_raw_prem_prems _ _ = [];
   567 
   568             fun close_prem_prem xs t =
   569               fold_rev Logic.all (map Free (drop (nn + length xs)
   570                 (rev (Term.add_frees t (map dest_Free xs @ phis'))))) t;
   571 
   572             fun mk_prem_prem xs (xysets, (j, x)) =
   573               close_prem_prem xs (Logic.list_implies (map (fn (x', (y, set)) =>
   574                   HOLogic.mk_Trueprop (HOLogic.mk_mem (y, set $ x'))) xysets,
   575                 HOLogic.mk_Trueprop (nth phis (j - 1) $ x)));
   576 
   577             fun mk_raw_prem phi ctr ctr_Ts =
   578               let
   579                 val (xs, names_lthy') = names_lthy |> mk_Frees "x" ctr_Ts;
   580                 val pprems = maps (mk_raw_prem_prems names_lthy') xs;
   581               in (xs, pprems, HOLogic.mk_Trueprop (phi $ Term.list_comb (ctr, xs))) end;
   582 
   583             fun mk_prem (xs, raw_pprems, concl) =
   584               fold_rev Logic.all xs (Logic.list_implies (map (mk_prem_prem xs) raw_pprems, concl));
   585 
   586             val raw_premss = map3 (map2 o mk_raw_prem) phis ctrss ctr_Tsss;
   587 
   588             val goal =
   589               Library.foldr (Logic.list_implies o apfst (map mk_prem)) (raw_premss,
   590                 HOLogic.mk_Trueprop (Library.foldr1 HOLogic.mk_conj
   591                   (map2 (curry (op $)) phis vs)));
   592 
   593             val kksss = map (map (map (fst o snd) o #2)) raw_premss;
   594 
   595             val fld_induct' = fp_induct OF (map mk_sumEN_tupled_balanced mss);
   596 
   597             val induct_thm =
   598               Skip_Proof.prove lthy [] [] goal (fn {context = ctxt, ...} =>
   599                 mk_induct_tac ctxt ns mss kksss (flat ctr_defss) fld_induct'
   600                   nested_set_natural's pre_set_defss)
   601               |> singleton (Proof_Context.export names_lthy lthy)
   602           in
   603             `(conj_dests nn) induct_thm
   604           end;
   605 
   606         val (iter_thmss, rec_thmss) =
   607           let
   608             val xctrss = map2 (map2 (curry Term.list_comb)) ctrss xsss;
   609             val giters = map (lists_bmoc gss) iters;
   610             val hrecs = map (lists_bmoc hss) recs;
   611 
   612             fun mk_goal_iter_like fss fiter_like xctr f xs fxs =
   613               fold_rev (fold_rev Logic.all) (xs :: fss)
   614                 (mk_Trueprop_eq (fiter_like $ xctr, Term.list_comb (f, fxs)));
   615 
   616             fun build_call fiter_likes maybe_tick (T, U) =
   617               if T = U then
   618                 id_const T
   619               else
   620                 (case find_index (curry (op =) T) fpTs of
   621                   ~1 => build_map (build_call fiter_likes maybe_tick) T U
   622                 | j => maybe_tick (nth vs j) (nth fiter_likes j));
   623 
   624             fun mk_U maybe_mk_prodT =
   625               typ_subst (map2 (fn fpT => fn C => (fpT, maybe_mk_prodT fpT C)) fpTs Cs);
   626 
   627             fun intr_calls fiter_likes maybe_cons maybe_tick maybe_mk_prodT (x as Free (_, T)) =
   628               if member (op =) fpTs T then
   629                 maybe_cons x [build_call fiter_likes (K I) (T, mk_U (K I) T) $ x]
   630               else if exists_fp_subtype T then
   631                 [build_call fiter_likes maybe_tick (T, mk_U maybe_mk_prodT T) $ x]
   632               else
   633                 [x];
   634 
   635             val gxsss = map (map (maps (intr_calls giters (K I) (K I) (K I)))) xsss;
   636             val hxsss = map (map (maps (intr_calls hrecs cons tick (curry HOLogic.mk_prodT)))) xsss;
   637 
   638             val goal_iterss = map5 (map4 o mk_goal_iter_like gss) giters xctrss gss xsss gxsss;
   639             val goal_recss = map5 (map4 o mk_goal_iter_like hss) hrecs xctrss hss xsss hxsss;
   640 
   641             val iter_tacss =
   642               map2 (map o mk_iter_like_tac pre_map_defs nesting_map_ids iter_defs) fp_iter_thms
   643                 ctr_defss;
   644             val rec_tacss =
   645               map2 (map o mk_iter_like_tac pre_map_defs nesting_map_ids rec_defs) fp_rec_thms
   646                 ctr_defss;
   647           in
   648             (map2 (map2 (fn goal => fn tac => Skip_Proof.prove lthy [] [] goal (tac o #context)))
   649                goal_iterss iter_tacss,
   650              map2 (map2 (fn goal => fn tac => Skip_Proof.prove lthy [] [] goal (tac o #context)))
   651                goal_recss rec_tacss)
   652           end;
   653 
   654         val common_notes =
   655           (if nn > 1 then [(inductN, [induct_thm], [])] (* FIXME: attribs *) else [])
   656           |> map (fn (thmN, thms, attrs) =>
   657               ((Binding.qualify true fp_common_name (Binding.name thmN), attrs), [(thms, [])]));
   658 
   659         val notes =
   660           [(inductN, map single induct_thms, []), (* FIXME: attribs *)
   661            (itersN, iter_thmss, simp_attrs),
   662            (recsN, rec_thmss, Code.add_default_eqn_attrib :: simp_attrs)]
   663           |> maps (fn (thmN, thmss, attrs) =>
   664             map2 (fn b => fn thms =>
   665               ((Binding.qualify true (Binding.name_of b) (Binding.name thmN), attrs),
   666                 [(thms, [])])) fp_bs thmss);
   667       in
   668         lthy |> Local_Theory.notes (common_notes @ notes) |> snd
   669       end;
   670 
   671     fun derive_coinduct_coiter_corec_thms_for_types ((ctrss, selsss, coiters, corecs, _, ctr_defss,
   672         discIss, sel_thmsss, coiter_defs, corec_defs), lthy) =
   673       let
   674         val (vs', _) =
   675           lthy
   676           |> Variable.variant_fixes (map Binding.name_of fp_bs);
   677 
   678         val vs = map2 (curry Free) vs' fpTs;
   679 
   680         val (coinduct_thms, coinduct_thm) =
   681           let
   682             val coinduct_thm = fp_induct;
   683           in
   684             `(conj_dests nn) coinduct_thm
   685           end;
   686 
   687         val (coiter_thmss, corec_thmss) =
   688           let
   689             val z = the_single zs;
   690             val gcoiters = map (lists_bmoc pgss) coiters;
   691             val hcorecs = map (lists_bmoc phss) corecs;
   692 
   693             fun mk_goal_cond pos = HOLogic.mk_Trueprop o (not pos ? HOLogic.mk_not);
   694 
   695             fun mk_goal_coiter_like pfss c cps fcoiter_like n k ctr m cfs' =
   696               fold_rev (fold_rev Logic.all) ([c] :: pfss)
   697                 (Logic.list_implies (seq_conds mk_goal_cond n k cps,
   698                    mk_Trueprop_eq (fcoiter_like $ c, Term.list_comb (ctr, take m cfs'))));
   699 
   700             fun build_call fiter_likes maybe_tack (T, U) =
   701               if T = U then
   702                 id_const T
   703               else
   704                 (case find_index (curry (op =) U) fpTs of
   705                   ~1 => build_map (build_call fiter_likes maybe_tack) T U
   706                 | j => maybe_tack (nth cs j, nth vs j) (nth fiter_likes j));
   707 
   708             fun mk_U maybe_mk_sumT =
   709               typ_subst (map2 (fn C => fn fpT => (maybe_mk_sumT fpT C, fpT)) Cs fpTs);
   710 
   711             fun intr_calls fiter_likes maybe_mk_sumT maybe_tack cqf =
   712               let val T = fastype_of cqf in
   713                 if exists_subtype (member (op =) Cs) T then
   714                   build_call fiter_likes maybe_tack (T, mk_U maybe_mk_sumT T) $ cqf
   715                 else
   716                   cqf
   717               end;
   718 
   719             val crgsss' = map (map (map (intr_calls gcoiters (K I) (K I)))) crgsss;
   720             val cshsss' = map (map (map (intr_calls hcorecs (curry mk_sumT) (tack z)))) cshsss;
   721 
   722             val goal_coiterss =
   723               map8 (map4 oooo mk_goal_coiter_like pgss) cs cpss gcoiters ns kss ctrss mss crgsss';
   724             val goal_corecss =
   725               map8 (map4 oooo mk_goal_coiter_like phss) cs cpss hcorecs ns kss ctrss mss cshsss';
   726 
   727             val coiter_tacss =
   728               map3 (map oo mk_coiter_like_tac coiter_defs nesting_map_ids) fp_iter_thms pre_map_defs
   729                 ctr_defss;
   730             val corec_tacss =
   731               map3 (map oo mk_coiter_like_tac corec_defs nesting_map_ids) fp_rec_thms pre_map_defs
   732                 ctr_defss;
   733           in
   734             (map2 (map2 (fn goal => fn tac =>
   735                  Skip_Proof.prove lthy [] [] goal (tac o #context) |> Thm.close_derivation))
   736                goal_coiterss coiter_tacss,
   737              map2 (map2 (fn goal => fn tac =>
   738                  Skip_Proof.prove lthy [] [] goal (tac o #context)
   739                  |> Local_Defs.unfold lthy @{thms sum_case_if} |> Thm.close_derivation))
   740                goal_corecss corec_tacss)
   741           end;
   742 
   743         fun mk_disc_coiter_like_thms [_] = K []
   744           | mk_disc_coiter_like_thms thms = map2 (curry (op RS)) thms;
   745 
   746         val disc_coiter_thmss = map2 mk_disc_coiter_like_thms coiter_thmss discIss;
   747         val disc_corec_thmss = map2 mk_disc_coiter_like_thms corec_thmss discIss;
   748 
   749         fun mk_sel_coiter_like_thm coiter_like_thm sel0 sel_thm =
   750           let
   751             val (domT, ranT) = dest_funT (fastype_of sel0);
   752             val arg_cong' =
   753               Drule.instantiate' (map (SOME o certifyT lthy) [domT, ranT])
   754                 [NONE, NONE, SOME (certify lthy sel0)] arg_cong
   755               |> Thm.varifyT_global;
   756             val sel_thm' = sel_thm RSN (2, trans);
   757           in
   758             coiter_like_thm RS arg_cong' RS sel_thm'
   759           end;
   760 
   761         val sel_coiter_thmsss =
   762           map3 (map3 (map2 o mk_sel_coiter_like_thm)) coiter_thmss selsss sel_thmsss;
   763         val sel_corec_thmsss =
   764           map3 (map3 (map2 o mk_sel_coiter_like_thm)) corec_thmss selsss sel_thmsss;
   765 
   766         val common_notes =
   767           (if nn > 1 then [(coinductN, [coinduct_thm], [])] (* FIXME: attribs *) else [])
   768           |> map (fn (thmN, thms, attrs) =>
   769               ((Binding.qualify true fp_common_name (Binding.name thmN), attrs), [(thms, [])]));
   770 
   771         val notes =
   772           [(coinductN, map single coinduct_thms, []), (* FIXME: attribs *)
   773            (coitersN, coiter_thmss, []),
   774            (disc_coitersN, disc_coiter_thmss, []),
   775            (sel_coitersN, map flat sel_coiter_thmsss, []),
   776            (corecsN, corec_thmss, []),
   777            (disc_corecsN, disc_corec_thmss, []),
   778            (sel_corecsN, map flat sel_corec_thmsss, [])]
   779           |> maps (fn (thmN, thmss, attrs) =>
   780             map_filter (fn (_, []) => NONE | (b, thms) =>
   781               SOME ((Binding.qualify true (Binding.name_of b) (Binding.name thmN), attrs),
   782                 [(thms, [])])) (fp_bs ~~ thmss));
   783       in
   784         lthy |> Local_Theory.notes (common_notes @ notes) |> snd
   785       end;
   786 
   787     fun wrap_types_and_define_iter_likes ((wraps, define_iter_likess), lthy) =
   788       fold_map2 (curry (op o)) define_iter_likess wraps lthy |>> split_list10
   789 
   790     val lthy' = lthy
   791       |> fold_map define_ctrs_case_for_type (fp_bs ~~ fpTs ~~ Cs ~~ flds ~~ unfs ~~ fp_iters ~~
   792         fp_recs ~~ fld_unfs ~~ unf_flds ~~ fld_injects ~~ ns ~~ kss ~~ mss ~~ ctr_bindingss ~~
   793         ctr_mixfixess ~~ ctr_Tsss ~~ disc_bindingss ~~ sel_bindingsss ~~ raw_sel_defaultsss)
   794       |>> split_list |> wrap_types_and_define_iter_likes
   795       |> (if lfp then derive_induct_iter_rec_thms_for_types
   796           else derive_coinduct_coiter_corec_thms_for_types);
   797 
   798     val timer = time (timer ("Constructors, discriminators, selectors, etc., for the new " ^
   799       (if lfp then "" else "co") ^ "datatype"));
   800   in
   801     timer; lthy'
   802   end;
   803 
   804 val datatyp = define_datatype (K I) (K I) (K I);
   805 
   806 val datatype_cmd = define_datatype Typedecl.read_constraint Syntax.parse_typ Syntax.read_term;
   807 
   808 val parse_binding_colon = Parse.binding --| @{keyword ":"};
   809 val parse_opt_binding_colon = Scan.optional parse_binding_colon no_binding;
   810 
   811 val parse_ctr_arg =
   812   @{keyword "("} |-- parse_binding_colon -- Parse.typ --| @{keyword ")"} ||
   813   (Parse.typ >> pair no_binding);
   814 
   815 val parse_defaults =
   816   @{keyword "("} |-- @{keyword "defaults"} |-- Scan.repeat parse_bound_term --| @{keyword ")"};
   817 
   818 val parse_single_spec =
   819   Parse.type_args_constrained -- Parse.binding -- Parse.opt_mixfix --
   820   (@{keyword "="} |-- Parse.enum1 "|" (parse_opt_binding_colon -- Parse.binding --
   821     Scan.repeat parse_ctr_arg -- Scan.optional parse_defaults [] -- Parse.opt_mixfix));
   822 
   823 val parse_datatype = parse_wrap_options -- Parse.and_list1 parse_single_spec;
   824 
   825 fun parse_datatype_cmd lfp construct = parse_datatype >> datatype_cmd lfp construct;
   826 
   827 end;