src/HOL/Codatatype/Tools/bnf_fp_sugar.ML
author blanchet
Fri, 14 Sep 2012 12:09:27 +0200
changeset 50378 8fc53d925629
parent 50377 1271aca16aed
child 50381 3edd1c90f6e6
permissions -rw-r--r--
distinguish between nested and nesting BNFs
     1 (*  Title:      HOL/Codatatype/Tools/bnf_fp_sugar.ML
     2     Author:     Jasmin Blanchette, TU Muenchen
     3     Copyright   2012
     4 
     5 Sugar for constructing LFPs and GFPs.
     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_list11 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, map #11 xs);
    40 
    41 fun strip_map_type (Type (@{type_name fun}, [T as Type _, T'])) = strip_map_type T' |>> cons T
    42   | strip_map_type T = ([], T);
    43 
    44 fun resort_tfree S (TFree (s, _)) = TFree (s, S);
    45 
    46 fun typ_subst inst (T as Type (s, Ts)) =
    47     (case AList.lookup (op =) inst T of
    48       NONE => Type (s, map (typ_subst inst) Ts)
    49     | SOME T' => T')
    50   | typ_subst inst T = the_default T (AList.lookup (op =) inst T);
    51 
    52 val lists_bmoc = fold (fn xs => fn t => Term.list_comb (t, xs));
    53 
    54 fun mk_id T = Const (@{const_name id}, T --> T);
    55 
    56 fun mk_tupled_fun x f xs = HOLogic.tupled_lambda x (Term.list_comb (f, xs));
    57 fun mk_uncurried_fun f xs = mk_tupled_fun (HOLogic.mk_tuple xs) f xs;
    58 fun mk_uncurried2_fun f xss =
    59   mk_tupled_fun (HOLogic.mk_tuple (map HOLogic.mk_tuple xss)) f (flat xss);
    60 
    61 fun tick v f = Term.lambda v (HOLogic.mk_prod (v, f $ v));
    62 
    63 fun tack z_name (c, v) f =
    64   let val z = Free (z_name, mk_sumT (fastype_of v, fastype_of c)) in
    65     Term.lambda z (mk_sum_case (Term.lambda v v, Term.lambda c (f $ c)) $ z)
    66   end;
    67 
    68 fun cannot_merge_types () = error "Mutually recursive types must have the same type parameters";
    69 
    70 fun merge_type_arg T T' = if T = T' then T else cannot_merge_types ();
    71 
    72 fun merge_type_args (As, As') =
    73   if length As = length As' then map2 merge_type_arg As As' else cannot_merge_types ();
    74 
    75 fun type_args_constrained_of (((cAs, _), _), _) = cAs;
    76 fun type_binding_of (((_, b), _), _) = b;
    77 fun mixfix_of ((_, mx), _) = mx;
    78 fun ctr_specs_of (_, ctr_specs) = ctr_specs;
    79 
    80 fun disc_of ((((disc, _), _), _), _) = disc;
    81 fun ctr_of ((((_, ctr), _), _), _) = ctr;
    82 fun args_of (((_, args), _), _) = args;
    83 fun defaults_of ((_, ds), _) = ds;
    84 fun ctr_mixfix_of (_, mx) = mx;
    85 
    86 fun define_datatype prepare_constraint prepare_typ prepare_term lfp construct (no_dests, specs)
    87     no_defs_lthy0 =
    88   let
    89     (* TODO: sanity checks on arguments *)
    90 
    91     val _ = if not lfp andalso no_dests then error "Cannot define destructor-less codatatypes"
    92       else ();
    93 
    94     val N = length specs;
    95     val fp_bs = map type_binding_of specs;
    96     val fp_common_name = mk_common_name fp_bs;
    97 
    98     fun prepare_type_arg (ty, c) =
    99       let val TFree (s, _) = prepare_typ no_defs_lthy0 ty in
   100         TFree (s, prepare_constraint no_defs_lthy0 c)
   101       end;
   102 
   103     val Ass0 = map (map prepare_type_arg o type_args_constrained_of) specs;
   104     val unsorted_Ass0 = map (map (resort_tfree HOLogic.typeS)) Ass0;
   105     val unsorted_As = Library.foldr1 merge_type_args unsorted_Ass0;
   106 
   107     val (((Bs, Cs), vs'), no_defs_lthy) =
   108       no_defs_lthy0
   109       |> fold (Variable.declare_typ o resort_tfree dummyS) unsorted_As
   110       |> mk_TFrees N
   111       ||>> mk_TFrees N
   112       ||>> Variable.variant_fixes (map Binding.name_of fp_bs);
   113 
   114     (* TODO: cleaner handling of fake contexts, without "background_theory" *)
   115     (*the "perhaps o try" below helps gracefully handles the case where the new type is defined in a
   116       locale and shadows an existing global type*)
   117     val fake_thy =
   118       Theory.copy #> fold (fn spec => perhaps (try (Sign.add_type no_defs_lthy
   119         (type_binding_of spec, length (type_args_constrained_of spec), mixfix_of spec)))) specs;
   120     val fake_lthy = Proof_Context.background_theory fake_thy no_defs_lthy;
   121 
   122     fun mk_fake_T b =
   123       Type (fst (Term.dest_Type (Proof_Context.read_type_name fake_lthy true (Binding.name_of b))),
   124         unsorted_As);
   125 
   126     val fake_Ts = map mk_fake_T fp_bs;
   127 
   128     val mixfixes = map mixfix_of specs;
   129 
   130     val _ = (case duplicates Binding.eq_name fp_bs of [] => ()
   131       | b :: _ => error ("Duplicate type name declaration " ^ quote (Binding.name_of b)));
   132 
   133     val ctr_specss = map ctr_specs_of specs;
   134 
   135     val disc_bindingss = map (map disc_of) ctr_specss;
   136     val ctr_bindingss =
   137       map2 (fn fp_b => map (Binding.qualify false (Binding.name_of fp_b) o ctr_of))
   138         fp_bs ctr_specss;
   139     val ctr_argsss = map (map args_of) ctr_specss;
   140     val ctr_mixfixess = map (map ctr_mixfix_of) ctr_specss;
   141 
   142     val sel_bindingsss = map (map (map fst)) ctr_argsss;
   143     val fake_ctr_Tsss0 = map (map (map (prepare_typ fake_lthy o snd))) ctr_argsss;
   144     val raw_sel_defaultsss = map (map defaults_of) ctr_specss;
   145 
   146     val (As :: _) :: fake_ctr_Tsss =
   147       burrow (burrow (Syntax.check_typs fake_lthy)) (Ass0 :: fake_ctr_Tsss0);
   148 
   149     val _ = (case duplicates (op =) unsorted_As of [] => ()
   150       | A :: _ => error ("Duplicate type parameter " ^
   151           quote (Syntax.string_of_typ no_defs_lthy A)));
   152 
   153     val rhs_As' = fold (fold (fold Term.add_tfreesT)) fake_ctr_Tsss [];
   154     val _ = (case subtract (op =) (map dest_TFree As) rhs_As' of
   155         [] => ()
   156       | A' :: _ => error ("Extra type variable on right-hand side: " ^
   157           quote (Syntax.string_of_typ no_defs_lthy (TFree A'))));
   158 
   159     fun eq_fpT (T as Type (s, Us)) (Type (s', Us')) =
   160         s = s' andalso (Us = Us' orelse error ("Illegal occurrence of recursive type " ^
   161           quote (Syntax.string_of_typ fake_lthy T)))
   162       | eq_fpT _ _ = false;
   163 
   164     fun freeze_fp (T as Type (s, Us)) =
   165         (case find_index (eq_fpT T) fake_Ts of ~1 => Type (s, map freeze_fp Us) | j => nth Bs j)
   166       | freeze_fp T = T;
   167 
   168     val ctr_TsssBs = map (map (map freeze_fp)) fake_ctr_Tsss;
   169     val ctr_sum_prod_TsBs = map (mk_sumTN_balanced o map HOLogic.mk_tupleT) ctr_TsssBs;
   170 
   171     val fp_eqs =
   172       map dest_TFree Bs ~~ map (Term.typ_subst_atomic (As ~~ unsorted_As)) ctr_sum_prod_TsBs;
   173 
   174     val (pre_bnfs, ((unfs0, flds0, fp_iters0, fp_recs0, fp_induct, unf_flds, fld_unfs, fld_injects,
   175         fp_iter_thms, fp_rec_thms), lthy)) =
   176       fp_bnf construct fp_bs mixfixes (map dest_TFree unsorted_As) fp_eqs no_defs_lthy0;
   177 
   178     fun add_nesty_bnf_names Us =
   179       let
   180         fun add (Type (s, Ts)) ss =
   181             let val (needs, ss') = fold_map add Ts ss in
   182               if exists I needs then (true, insert (op =) s ss') else (false, ss')
   183             end
   184           | add T ss = (member (op =) Us T, ss);
   185       in snd oo add end;
   186 
   187     fun nesty_bnfs Us =
   188       map_filter (bnf_of lthy) (fold (fold (fold (add_nesty_bnf_names Us))) ctr_TsssBs []);
   189 
   190     val nesting_bnfs = nesty_bnfs As;
   191     val nested_bnfs = nesty_bnfs Bs;
   192 
   193     val timer = time (Timer.startRealTimer ());
   194 
   195     fun mk_unf_or_fld get_T Ts t =
   196       let val Type (_, Ts0) = get_T (fastype_of t) in
   197         Term.subst_atomic_types (Ts0 ~~ Ts) t
   198       end;
   199 
   200     val mk_unf = mk_unf_or_fld domain_type;
   201     val mk_fld = mk_unf_or_fld range_type;
   202 
   203     val unfs = map (mk_unf As) unfs0;
   204     val flds = map (mk_fld As) flds0;
   205 
   206     val fpTs = map (domain_type o fastype_of) unfs;
   207 
   208     val exists_fp_subtype = exists_subtype (member (op =) fpTs);
   209 
   210     val vs = map2 (curry Free) vs' fpTs;
   211 
   212     val ctr_Tsss = map (map (map (Term.typ_subst_atomic (Bs ~~ fpTs)))) ctr_TsssBs;
   213     val ns = map length ctr_Tsss;
   214     val kss = map (fn n => 1 upto n) ns;
   215     val mss = map (map length) ctr_Tsss;
   216     val Css = map2 replicate ns Cs;
   217 
   218     fun mk_iter_like Ts Us t =
   219       let
   220         val (bindings, body) = strip_type (fastype_of t);
   221         val (f_Us, prebody) = split_last bindings;
   222         val Type (_, Ts0) = if lfp then prebody else body;
   223         val Us0 = distinct (op =) (map (if lfp then body_type else domain_type) f_Us);
   224       in
   225         Term.subst_atomic_types (Ts0 @ Us0 ~~ Ts @ Us) t
   226       end;
   227 
   228     val fp_iters as fp_iter1 :: _ = map (mk_iter_like As Cs) fp_iters0;
   229     val fp_recs as fp_rec1 :: _ = map (mk_iter_like As Cs) fp_recs0;
   230 
   231     val fp_iter_fun_Ts = fst (split_last (binder_types (fastype_of fp_iter1)));
   232     val fp_rec_fun_Ts = fst (split_last (binder_types (fastype_of fp_rec1)));
   233 
   234     val ((iter_only as (gss, _, _), rec_only as (hss, _, _)),
   235          (zs, cs, cpss, coiter_only as ((pgss, crgsss), _), corec_only as ((phss, cshsss), _))) =
   236       if lfp then
   237         let
   238           val y_Tsss =
   239             map3 (fn n => fn ms => map2 dest_tupleT ms o dest_sumTN_balanced n o domain_type)
   240               ns mss fp_iter_fun_Ts;
   241           val g_Tss = map2 (map2 (curry (op --->))) y_Tsss Css;
   242 
   243           val ((gss, ysss), _) =
   244             lthy
   245             |> mk_Freess "f" g_Tss
   246             ||>> mk_Freesss "x" y_Tsss;
   247           val yssss = map (map (map single)) ysss;
   248 
   249           fun dest_rec_prodT (T as Type (@{type_name prod}, Us as [_, U])) =
   250               if member (op =) Cs U then Us else [T]
   251             | dest_rec_prodT T = [T];
   252 
   253           val z_Tssss =
   254             map3 (fn n => fn ms => map2 (map dest_rec_prodT oo dest_tupleT) ms o
   255               dest_sumTN_balanced n o domain_type) ns mss fp_rec_fun_Ts;
   256           val h_Tss = map2 (map2 (fold_rev (curry (op --->)))) z_Tssss Css;
   257 
   258           val hss = map2 (map2 retype_free) h_Tss gss;
   259           val zssss_hd = map2 (map2 (map2 (retype_free o hd))) z_Tssss ysss;
   260           val (zssss_tl, _) =
   261             lthy
   262             |> mk_Freessss "y" (map (map (map tl)) z_Tssss);
   263           val zssss = map2 (map2 (map2 cons)) zssss_hd zssss_tl;
   264         in
   265           (((gss, g_Tss, yssss), (hss, h_Tss, zssss)),
   266            ([], [], [], (([], []), ([], [])), (([], []), ([], []))))
   267         end
   268       else
   269         let
   270           (*avoid "'a itself" arguments in coiterators and corecursors*)
   271           val mss' =  map (fn [0] => [1] | ms => ms) mss;
   272 
   273           val p_Tss = map2 (fn n => replicate (Int.max (0, n - 1)) o mk_predT) ns Cs;
   274 
   275           fun zip_predss_getterss qss fss = maps (op @) (qss ~~ fss);
   276 
   277           fun zip_preds_predsss_gettersss [] [qss] [fss] = zip_predss_getterss qss fss
   278             | zip_preds_predsss_gettersss (p :: ps) (qss :: qsss) (fss :: fsss) =
   279               p :: zip_predss_getterss qss fss @ zip_preds_predsss_gettersss ps qsss fsss;
   280 
   281           fun mk_types maybe_dest_sumT fun_Ts =
   282             let
   283               val f_sum_prod_Ts = map range_type fun_Ts;
   284               val f_prod_Tss = map2 dest_sumTN_balanced ns f_sum_prod_Ts;
   285               val f_Tssss =
   286                 map3 (fn C => map2 (map (map (curry (op -->) C) o maybe_dest_sumT) oo dest_tupleT))
   287                   Cs mss' f_prod_Tss;
   288               val q_Tssss =
   289                 map (map (map (fn [_] => [] | [_, C] => [mk_predT (domain_type C)]))) f_Tssss;
   290               val pf_Tss = map3 zip_preds_predsss_gettersss p_Tss q_Tssss f_Tssss;
   291             in (q_Tssss, f_sum_prod_Ts, f_Tssss, pf_Tss) end;
   292 
   293           val (r_Tssss, g_sum_prod_Ts, g_Tssss, pg_Tss) = mk_types single fp_iter_fun_Ts;
   294 
   295           val ((((Free (z, _), cs), pss), gssss), _) =
   296             lthy
   297             |> yield_singleton (mk_Frees "z") dummyT
   298             ||>> mk_Frees "a" Cs
   299             ||>> mk_Freess "p" p_Tss
   300             ||>> mk_Freessss "g" g_Tssss;
   301           val rssss = map (map (map (fn [] => []))) r_Tssss;
   302 
   303           fun dest_corec_sumT (T as Type (@{type_name sum}, Us as [_, U])) =
   304               if member (op =) Cs U then Us else [T]
   305             | dest_corec_sumT T = [T];
   306 
   307           val (s_Tssss, h_sum_prod_Ts, h_Tssss, ph_Tss) = mk_types dest_corec_sumT fp_rec_fun_Ts;
   308 
   309           val hssss_hd = map2 (map2 (map2 (fn T :: _ => fn [g] => retype_free T g))) h_Tssss gssss;
   310           val ((sssss, hssss_tl), _) =
   311             lthy
   312             |> mk_Freessss "q" s_Tssss
   313             ||>> mk_Freessss "h" (map (map (map tl)) h_Tssss);
   314           val hssss = map2 (map2 (map2 cons)) hssss_hd hssss_tl;
   315 
   316           val cpss = map2 (fn c => map (fn p => p $ c)) cs pss;
   317 
   318           fun mk_preds_getters_join [] [cf] = cf
   319             | mk_preds_getters_join [cq] [cf, cf'] =
   320               mk_If cq (mk_Inl (fastype_of cf') cf) (mk_Inr (fastype_of cf) cf');
   321 
   322           fun mk_terms qssss fssss =
   323             let
   324               val pfss = map3 zip_preds_predsss_gettersss pss qssss fssss;
   325               val cqssss = map2 (fn c => map (map (map (fn f => f $ c)))) cs qssss;
   326               val cfssss = map2 (fn c => map (map (map (fn f => f $ c)))) cs fssss;
   327               val cqfsss = map2 (map2 (map2 mk_preds_getters_join)) cqssss cfssss;
   328             in (pfss, cqfsss) end;
   329         in
   330           ((([], [], []), ([], [], [])),
   331            ([z], cs, cpss, (mk_terms rssss gssss, (g_sum_prod_Ts, pg_Tss)),
   332             (mk_terms sssss hssss, (h_sum_prod_Ts, ph_Tss))))
   333         end;
   334 
   335     fun define_ctrs_case_for_type (((((((((((((((((((fp_b, fpT), C), v), fld), unf), fp_iter),
   336           fp_rec), fld_unf), unf_fld), fld_inject), n), ks), ms), ctr_bindings), ctr_mixfixes),
   337         ctr_Tss), disc_bindings), sel_bindingss), raw_sel_defaultss) no_defs_lthy =
   338       let
   339         val unfT = domain_type (fastype_of fld);
   340         val ctr_prod_Ts = map HOLogic.mk_tupleT ctr_Tss;
   341         val ctr_sum_prod_T = mk_sumTN_balanced ctr_prod_Ts;
   342         val case_Ts = map (fn Ts => Ts ---> C) ctr_Tss;
   343 
   344         val (((u, fs), xss), _) =
   345           no_defs_lthy
   346           |> yield_singleton (mk_Frees "u") unfT
   347           ||>> mk_Frees "f" case_Ts
   348           ||>> mk_Freess "x" ctr_Tss;
   349 
   350         val ctr_rhss =
   351           map2 (fn k => fn xs => fold_rev Term.lambda xs (fld $
   352             mk_InN_balanced ctr_sum_prod_T n (HOLogic.mk_tuple xs) k)) ks xss;
   353 
   354         val case_binding = Binding.suffix_name ("_" ^ caseN) fp_b;
   355 
   356         val case_rhs =
   357           fold_rev Term.lambda (fs @ [v])
   358             (mk_sum_caseN_balanced (map2 mk_uncurried_fun fs xss) $ (unf $ v));
   359 
   360         val ((raw_case :: raw_ctrs, raw_case_def :: raw_ctr_defs), (lthy', lthy)) = no_defs_lthy
   361           |> apfst split_list o fold_map3 (fn b => fn mx => fn rhs =>
   362               Local_Theory.define ((b, mx), ((Thm.def_binding b, []), rhs)) #>> apsnd snd)
   363             (case_binding :: ctr_bindings) (NoSyn :: ctr_mixfixes) (case_rhs :: ctr_rhss)
   364           ||> `Local_Theory.restore;
   365 
   366         val phi = Proof_Context.export_morphism lthy lthy';
   367 
   368         val ctr_defs = map (Morphism.thm phi) raw_ctr_defs;
   369         val case_def = Morphism.thm phi raw_case_def;
   370 
   371         val ctrs0 = map (Morphism.term phi) raw_ctrs;
   372         val casex0 = Morphism.term phi raw_case;
   373 
   374         val ctrs = map (mk_ctr As) ctrs0;
   375 
   376         fun exhaust_tac {context = ctxt, ...} =
   377           let
   378             val fld_iff_unf_thm =
   379               let
   380                 val goal =
   381                   fold_rev Logic.all [u, v]
   382                     (mk_Trueprop_eq (HOLogic.mk_eq (v, fld $ u), HOLogic.mk_eq (unf $ v, u)));
   383               in
   384                 Skip_Proof.prove lthy [] [] goal (fn {context = ctxt, ...} =>
   385                   mk_fld_iff_unf_tac ctxt (map (SOME o certifyT lthy) [unfT, fpT])
   386                     (certify lthy fld) (certify lthy unf) fld_unf unf_fld)
   387                 |> Thm.close_derivation
   388                 |> Morphism.thm phi
   389               end;
   390 
   391             val sumEN_thm' =
   392               Local_Defs.unfold lthy @{thms all_unit_eq}
   393                 (Drule.instantiate' (map (SOME o certifyT lthy) ctr_prod_Ts) []
   394                    (mk_sumEN_balanced n))
   395               |> Morphism.thm phi;
   396           in
   397             mk_exhaust_tac ctxt n ctr_defs fld_iff_unf_thm sumEN_thm'
   398           end;
   399 
   400         val inject_tacss =
   401           map2 (fn 0 => K [] | _ => fn ctr_def => [fn {context = ctxt, ...} =>
   402               mk_inject_tac ctxt ctr_def fld_inject]) ms ctr_defs;
   403 
   404         val half_distinct_tacss =
   405           map (map (fn (def, def') => fn {context = ctxt, ...} =>
   406             mk_half_distinct_tac ctxt fld_inject [def, def'])) (mk_half_pairss ctr_defs);
   407 
   408         val case_tacs =
   409           map3 (fn k => fn m => fn ctr_def => fn {context = ctxt, ...} =>
   410             mk_case_tac ctxt n k m case_def ctr_def unf_fld) ks ms ctr_defs;
   411 
   412         val tacss = [exhaust_tac] :: inject_tacss @ half_distinct_tacss @ [case_tacs];
   413 
   414         fun define_iter_rec ((selss0, discIs, sel_thmss), no_defs_lthy) =
   415           let
   416             val fpT_to_C = fpT --> C;
   417 
   418             fun generate_iter_like (suf, fp_iter_like, (fss, f_Tss, xssss)) =
   419               let
   420                 val res_T = fold_rev (curry (op --->)) f_Tss fpT_to_C;
   421                 val binding = Binding.suffix_name ("_" ^ suf) fp_b;
   422                 val spec =
   423                   mk_Trueprop_eq (lists_bmoc fss (Free (Binding.name_of binding, res_T)),
   424                     Term.list_comb (fp_iter_like,
   425                       map2 (mk_sum_caseN_balanced oo map2 mk_uncurried2_fun) fss xssss));
   426               in (binding, spec) end;
   427 
   428             val iter_like_infos =
   429               [(iterN, fp_iter, iter_only),
   430                (recN, fp_rec, rec_only)];
   431 
   432             val (bindings, specs) = map generate_iter_like iter_like_infos |> split_list;
   433 
   434             val ((csts, defs), (lthy', lthy)) = no_defs_lthy
   435               |> apfst split_list o fold_map2 (fn b => fn spec =>
   436                 Specification.definition (SOME (b, NONE, NoSyn), ((Thm.def_binding b, []), spec))
   437                 #>> apsnd snd) bindings specs
   438               ||> `Local_Theory.restore;
   439 
   440             val phi = Proof_Context.export_morphism lthy lthy';
   441 
   442             val [iter_def, rec_def] = map (Morphism.thm phi) defs;
   443 
   444             val [iter, recx] = map (mk_iter_like As Cs o Morphism.term phi) csts;
   445           in
   446             ((ctrs, selss0, iter, recx, v, xss, ctr_defs, discIs, sel_thmss, iter_def, rec_def),
   447              lthy)
   448           end;
   449 
   450         fun define_coiter_corec ((selss0, discIs, sel_thmss), no_defs_lthy) =
   451           let
   452             val B_to_fpT = C --> fpT;
   453 
   454             fun mk_preds_getterss_join c n cps sum_prod_T cqfss =
   455               Term.lambda c (mk_IfN sum_prod_T cps
   456                 (map2 (mk_InN_balanced sum_prod_T n) (map HOLogic.mk_tuple cqfss) (1 upto n)));
   457 
   458             fun generate_coiter_like (suf, fp_iter_like, ((pfss, cqfsss), (f_sum_prod_Ts,
   459                 pf_Tss))) =
   460               let
   461                 val res_T = fold_rev (curry (op --->)) pf_Tss B_to_fpT;
   462                 val binding = Binding.suffix_name ("_" ^ suf) fp_b;
   463                 val spec =
   464                   mk_Trueprop_eq (lists_bmoc pfss (Free (Binding.name_of binding, res_T)),
   465                     Term.list_comb (fp_iter_like,
   466                       map5 mk_preds_getterss_join cs ns cpss f_sum_prod_Ts cqfsss));
   467               in (binding, spec) end;
   468 
   469             val coiter_like_infos =
   470               [(coiterN, fp_iter, coiter_only),
   471                (corecN, fp_rec, corec_only)];
   472 
   473             val (bindings, specs) = map generate_coiter_like coiter_like_infos |> split_list;
   474 
   475             val ((csts, defs), (lthy', lthy)) = no_defs_lthy
   476               |> apfst split_list o fold_map2 (fn b => fn spec =>
   477                 Specification.definition (SOME (b, NONE, NoSyn), ((Thm.def_binding b, []), spec))
   478                 #>> apsnd snd) bindings specs
   479               ||> `Local_Theory.restore;
   480 
   481             val phi = Proof_Context.export_morphism lthy lthy';
   482 
   483             val [coiter_def, corec_def] = map (Morphism.thm phi) defs;
   484 
   485             val [coiter, corec] = map (mk_iter_like As Cs o Morphism.term phi) csts;
   486           in
   487             ((ctrs, selss0, coiter, corec, v, xss, ctr_defs, discIs, sel_thmss, coiter_def,
   488               corec_def), lthy)
   489           end;
   490 
   491         fun wrap lthy =
   492           let val sel_defaultss = map (map (apsnd (prepare_term lthy))) raw_sel_defaultss in
   493             wrap_datatype tacss (((no_dests, ctrs0), casex0), (disc_bindings, (sel_bindingss,
   494               sel_defaultss))) lthy
   495           end;
   496 
   497         val define_iter_likes = if lfp then define_iter_rec else define_coiter_corec;
   498       in
   499         ((wrap, define_iter_likes), lthy')
   500       end;
   501 
   502     val pre_map_defs = map map_def_of_bnf pre_bnfs;
   503     val pre_set_defss = map set_defs_of_bnf pre_bnfs;
   504     val nesting_map_ids = map map_id_of_bnf nesting_bnfs;
   505 
   506     fun mk_map Ts Us t =
   507       let val (Type (_, Ts0), Type (_, Us0)) = strip_map_type (fastype_of t) |>> List.last in
   508         Term.subst_atomic_types (Ts0 @ Us0 ~~ Ts @ Us) t
   509       end;
   510 
   511     fun build_map build_arg (Type (s, Ts)) (Type (_, Us)) =
   512       let
   513         val map0 = map_of_bnf (the (bnf_of lthy s));
   514         val mapx = mk_map Ts Us map0;
   515         val TUs = map dest_funT (fst (split_last (fst (strip_map_type (fastype_of mapx)))));
   516         val args = map build_arg TUs;
   517       in Term.list_comb (mapx, args) end;
   518 
   519     fun derive_induct_iter_rec_thms_for_types ((ctrss, _, iters, recs, vs, xsss, ctr_defss, _, _,
   520         iter_defs, rec_defs), lthy) =
   521       let
   522         fun mk_sets_nested bnf =
   523           let
   524             val Type (T_name, Us) = T_of_bnf bnf;
   525             val lives = lives_of_bnf bnf;
   526             val sets = sets_of_bnf bnf;
   527             fun mk_set U =
   528               (case find_index (curry (op =) U) lives of
   529                 ~1 => Term.dummy
   530               | i => nth sets i);
   531           in
   532             (T_name, map mk_set Us)
   533           end;
   534 
   535         val setss_nested = map mk_sets_nested nested_bnfs;
   536 
   537         val (induct_thms, induct_thm) =
   538           let
   539             val ((phis, phis'), names_lthy) =
   540               lthy
   541               |> mk_Frees' "P" (map mk_predT fpTs);
   542 
   543             fun mk_set Ts t =
   544               let val Type (_, Ts0) = domain_type (fastype_of t) in
   545                 Term.subst_atomic_types (Ts0 ~~ Ts) t
   546               end;
   547 
   548             fun mk_prem_prems names_lthy (x as Free (s, T as Type (T_name, Ts0))) =
   549                 (case find_index (curry (op =) T) fpTs of
   550                   ~1 =>
   551                   (case AList.lookup (op =) setss_nested T_name of
   552                     NONE => []
   553                   | SOME raw_sets0 =>
   554                     let
   555                       val (Ts, raw_sets) =
   556                         split_list (filter (exists_fp_subtype o fst) (Ts0 ~~ raw_sets0));
   557                       val sets = map (mk_set Ts0) raw_sets;
   558                       val (ys, names_lthy') = names_lthy |> mk_Frees s Ts;
   559                       val heads =
   560                         map2 (fn y => fn set => HOLogic.mk_Trueprop (HOLogic.mk_mem (y, set $ x)))
   561                           ys sets;
   562                       val bodies = flat (map (mk_prem_prems names_lthy') ys);
   563                     in
   564                       map2 (curry Logic.mk_implies) heads bodies
   565                     end)
   566                 | i => [HOLogic.mk_Trueprop (nth phis i $ x)])
   567               | mk_prem_prems _ _ = [];
   568 
   569             fun close_prem_prem (Free x') t =
   570               fold_rev Logic.all (map Free (drop (N + 1) (rev (Term.add_frees t (x' :: phis'))))) t;
   571 
   572             fun mk_prem phi ctr ctr_Ts =
   573               let
   574                 val (xs, names_lthy') = names_lthy |> mk_Frees "x" ctr_Ts;
   575                 val prem_prems =
   576                   maps (fn x => map (close_prem_prem x) (mk_prem_prems names_lthy' x)) xs;
   577               in
   578                 fold_rev Logic.all xs
   579                   (Logic.list_implies (prem_prems,
   580                      HOLogic.mk_Trueprop (phi $ Term.list_comb (ctr, xs))))
   581               end;
   582 
   583             val goal =
   584               fold_rev (fold_rev Logic.all) [phis, vs]
   585                 (Library.foldr Logic.list_implies (map3 (map2 o mk_prem) phis ctrss ctr_Tsss,
   586                    HOLogic.mk_Trueprop (Library.foldr1 HOLogic.mk_conj
   587                      (map2 (curry (op $)) phis vs))));
   588 
   589             val induct_thm =
   590               Skip_Proof.prove lthy [] [] goal (fn {context = ctxt, ...} =>
   591                 mk_induct_tac ctxt);
   592           in
   593             `(conj_dests N) induct_thm
   594           end;
   595 
   596         val (iter_thmss, rec_thmss) =
   597           let
   598             val xctrss = map2 (map2 (curry Term.list_comb)) ctrss xsss;
   599             val giters = map (lists_bmoc gss) iters;
   600             val hrecs = map (lists_bmoc hss) recs;
   601 
   602             fun mk_goal_iter_like fss fiter_like xctr f xs fxs =
   603               fold_rev (fold_rev Logic.all) (xs :: fss)
   604                 (mk_Trueprop_eq (fiter_like $ xctr, Term.list_comb (f, fxs)));
   605 
   606             fun build_call fiter_likes maybe_tick (T, U) =
   607               if T = U then
   608                 mk_id T
   609               else
   610                 (case find_index (curry (op =) T) fpTs of
   611                   ~1 => build_map (build_call fiter_likes maybe_tick) T U
   612                 | j => maybe_tick (nth vs j) (nth fiter_likes j));
   613 
   614             fun mk_U maybe_mk_prodT =
   615               typ_subst (map2 (fn fpT => fn C => (fpT, maybe_mk_prodT fpT C)) fpTs Cs);
   616 
   617             fun intr_calls fiter_likes maybe_cons maybe_tick maybe_mk_prodT (x as Free (_, T)) =
   618               if member (op =) fpTs T then
   619                 maybe_cons x [build_call fiter_likes (K I) (T, mk_U (K I) T) $ x]
   620               else if exists_fp_subtype T then
   621                 [build_call fiter_likes maybe_tick (T, mk_U maybe_mk_prodT T) $ x]
   622               else
   623                 [x];
   624 
   625             val gxsss = map (map (maps (intr_calls giters (K I) (K I) (K I)))) xsss;
   626             val hxsss = map (map (maps (intr_calls hrecs cons tick (curry HOLogic.mk_prodT)))) xsss;
   627 
   628             val goal_iterss = map5 (map4 o mk_goal_iter_like gss) giters xctrss gss xsss gxsss;
   629             val goal_recss = map5 (map4 o mk_goal_iter_like hss) hrecs xctrss hss xsss hxsss;
   630 
   631             val iter_tacss =
   632               map2 (map o mk_iter_like_tac pre_map_defs nesting_map_ids iter_defs) fp_iter_thms
   633                 ctr_defss;
   634             val rec_tacss =
   635               map2 (map o mk_iter_like_tac pre_map_defs nesting_map_ids rec_defs) fp_rec_thms
   636                 ctr_defss;
   637           in
   638             (map2 (map2 (fn goal => fn tac => Skip_Proof.prove lthy [] [] goal (tac o #context)))
   639                goal_iterss iter_tacss,
   640              map2 (map2 (fn goal => fn tac => Skip_Proof.prove lthy [] [] goal (tac o #context)))
   641                goal_recss rec_tacss)
   642           end;
   643 
   644         val common_notes =
   645           (if N > 1 then [(inductN, [induct_thm], [])] (* FIXME: attribs *) else [])
   646           |> map (fn (thmN, thms, attrs) =>
   647               ((Binding.qualify true fp_common_name (Binding.name thmN), attrs), [(thms, [])]));
   648 
   649         val notes =
   650           [(inductN, map single induct_thms, []), (* FIXME: attribs *)
   651            (itersN, iter_thmss, simp_attrs),
   652            (recsN, rec_thmss, Code.add_default_eqn_attrib :: simp_attrs)]
   653           |> maps (fn (thmN, thmss, attrs) =>
   654             map2 (fn b => fn thms =>
   655               ((Binding.qualify true (Binding.name_of b) (Binding.name thmN), attrs),
   656                 [(thms, [])])) fp_bs thmss);
   657       in
   658         lthy |> Local_Theory.notes (common_notes @ notes) |> snd
   659       end;
   660 
   661     fun derive_coinduct_coiter_corec_thms_for_types ((ctrss, selsss, coiters, corecs, vs, _,
   662         ctr_defss, discIss, sel_thmsss, coiter_defs, corec_defs), lthy) =
   663       let
   664         val (coinduct_thms, coinduct_thm) =
   665           let
   666             val coinduct_thm = fp_induct;
   667           in
   668             `(conj_dests N) coinduct_thm
   669           end;
   670 
   671         val (coiter_thmss, corec_thmss) =
   672           let
   673             val z = the_single zs;
   674             val gcoiters = map (lists_bmoc pgss) coiters;
   675             val hcorecs = map (lists_bmoc phss) corecs;
   676 
   677             fun mk_goal_cond pos = HOLogic.mk_Trueprop o (not pos ? HOLogic.mk_not);
   678 
   679             fun mk_goal_coiter_like pfss c cps fcoiter_like n k ctr m cfs' =
   680               fold_rev (fold_rev Logic.all) ([c] :: pfss)
   681                 (Logic.list_implies (seq_conds mk_goal_cond n k cps,
   682                    mk_Trueprop_eq (fcoiter_like $ c, Term.list_comb (ctr, take m cfs'))));
   683 
   684             fun build_call fiter_likes maybe_tack (T, U) =
   685               if T = U then
   686                 mk_id T
   687               else
   688                 (case find_index (curry (op =) U) fpTs of
   689                   ~1 => build_map (build_call fiter_likes maybe_tack) T U
   690                 | j => maybe_tack (nth cs j, nth vs j) (nth fiter_likes j));
   691 
   692             fun mk_U maybe_mk_sumT =
   693               typ_subst (map2 (fn C => fn fpT => (maybe_mk_sumT fpT C, fpT)) Cs fpTs);
   694 
   695             fun intr_calls fiter_likes maybe_mk_sumT maybe_tack cqf =
   696               let val T = fastype_of cqf in
   697                 if exists_subtype (member (op =) Cs) T then
   698                   build_call fiter_likes maybe_tack (T, mk_U maybe_mk_sumT T) $ cqf
   699                 else
   700                   cqf
   701               end;
   702 
   703             val crgsss' = map (map (map (intr_calls gcoiters (K I) (K I)))) crgsss;
   704             val cshsss' = map (map (map (intr_calls hcorecs (curry mk_sumT) (tack z)))) cshsss;
   705 
   706             val goal_coiterss =
   707               map8 (map4 oooo mk_goal_coiter_like pgss) cs cpss gcoiters ns kss ctrss mss crgsss';
   708             val goal_corecss =
   709               map8 (map4 oooo mk_goal_coiter_like phss) cs cpss hcorecs ns kss ctrss mss cshsss';
   710 
   711             val coiter_tacss =
   712               map3 (map oo mk_coiter_like_tac coiter_defs nesting_map_ids) fp_iter_thms pre_map_defs
   713                 ctr_defss;
   714             val corec_tacss =
   715               map3 (map oo mk_coiter_like_tac corec_defs nesting_map_ids) fp_rec_thms pre_map_defs
   716                 ctr_defss;
   717           in
   718             (map2 (map2 (fn goal => fn tac =>
   719                  Skip_Proof.prove lthy [] [] goal (tac o #context) |> Thm.close_derivation))
   720                goal_coiterss coiter_tacss,
   721              map2 (map2 (fn goal => fn tac =>
   722                  Skip_Proof.prove lthy [] [] goal (tac o #context)
   723                  |> Local_Defs.unfold lthy @{thms sum_case_if} |> Thm.close_derivation))
   724                goal_corecss corec_tacss)
   725           end;
   726 
   727         fun mk_disc_coiter_like_thms [_] = K []
   728           | mk_disc_coiter_like_thms thms = map2 (curry (op RS)) thms;
   729 
   730         val disc_coiter_thmss = map2 mk_disc_coiter_like_thms coiter_thmss discIss;
   731         val disc_corec_thmss = map2 mk_disc_coiter_like_thms corec_thmss discIss;
   732 
   733         fun mk_sel_coiter_like_thm coiter_like_thm sel0 sel_thm =
   734           let
   735             val (domT, ranT) = dest_funT (fastype_of sel0);
   736             val arg_cong' =
   737               Drule.instantiate' (map (SOME o certifyT lthy) [domT, ranT])
   738                 [NONE, NONE, SOME (certify lthy sel0)] arg_cong
   739               |> Thm.varifyT_global;
   740             val sel_thm' = sel_thm RSN (2, trans);
   741           in
   742             coiter_like_thm RS arg_cong' RS sel_thm'
   743           end;
   744 
   745         val sel_coiter_thmsss =
   746           map3 (map3 (map2 o mk_sel_coiter_like_thm)) coiter_thmss selsss sel_thmsss;
   747         val sel_corec_thmsss =
   748           map3 (map3 (map2 o mk_sel_coiter_like_thm)) corec_thmss selsss sel_thmsss;
   749 
   750         val common_notes =
   751           (if N > 1 then [(coinductN, [coinduct_thm], [])] (* FIXME: attribs *) else [])
   752           |> map (fn (thmN, thms, attrs) =>
   753               ((Binding.qualify true fp_common_name (Binding.name thmN), attrs), [(thms, [])]));
   754 
   755         val notes =
   756           [(coinductN, map single coinduct_thms, []), (* FIXME: attribs *)
   757            (coitersN, coiter_thmss, []),
   758            (disc_coitersN, disc_coiter_thmss, []),
   759            (sel_coitersN, map flat sel_coiter_thmsss, []),
   760            (corecsN, corec_thmss, []),
   761            (disc_corecsN, disc_corec_thmss, []),
   762            (sel_corecsN, map flat sel_corec_thmsss, [])]
   763           |> maps (fn (thmN, thmss, attrs) =>
   764             map_filter (fn (_, []) => NONE | (b, thms) =>
   765               SOME ((Binding.qualify true (Binding.name_of b) (Binding.name thmN), attrs),
   766                 [(thms, [])])) (fp_bs ~~ thmss));
   767       in
   768         lthy |> Local_Theory.notes (common_notes @ notes) |> snd
   769       end;
   770 
   771     fun wrap_types_and_define_iter_likes ((wraps, define_iter_likess), lthy) =
   772       fold_map2 (curry (op o)) define_iter_likess wraps lthy |>> split_list11
   773 
   774     val lthy' = lthy
   775       |> fold_map define_ctrs_case_for_type (fp_bs ~~ fpTs ~~ Cs ~~ vs ~~ flds ~~ unfs ~~
   776         fp_iters ~~ fp_recs ~~ fld_unfs ~~ unf_flds ~~ fld_injects ~~ ns ~~ kss ~~ mss ~~
   777         ctr_bindingss ~~ ctr_mixfixess ~~ ctr_Tsss ~~ disc_bindingss ~~ sel_bindingsss ~~
   778         raw_sel_defaultsss)
   779       |>> split_list |> wrap_types_and_define_iter_likes
   780       |> (if lfp then derive_induct_iter_rec_thms_for_types
   781           else derive_coinduct_coiter_corec_thms_for_types);
   782 
   783     val timer = time (timer ("Constructors, discriminators, selectors, etc., for the new " ^
   784       (if lfp then "" else "co") ^ "datatype"));
   785   in
   786     timer; lthy'
   787   end;
   788 
   789 val datatyp = define_datatype (K I) (K I) (K I);
   790 
   791 val datatype_cmd = define_datatype Typedecl.read_constraint Syntax.parse_typ Syntax.read_term;
   792 
   793 val parse_binding_colon = Parse.binding --| @{keyword ":"};
   794 val parse_opt_binding_colon = Scan.optional parse_binding_colon no_binding;
   795 
   796 val parse_ctr_arg =
   797   @{keyword "("} |-- parse_binding_colon -- Parse.typ --| @{keyword ")"} ||
   798   (Parse.typ >> pair no_binding);
   799 
   800 val parse_defaults =
   801   @{keyword "("} |-- @{keyword "defaults"} |-- Scan.repeat parse_bound_term --| @{keyword ")"};
   802 
   803 val parse_single_spec =
   804   Parse.type_args_constrained -- Parse.binding -- Parse.opt_mixfix --
   805   (@{keyword "="} |-- Parse.enum1 "|" (parse_opt_binding_colon -- Parse.binding --
   806     Scan.repeat parse_ctr_arg -- Scan.optional parse_defaults [] -- Parse.opt_mixfix));
   807 
   808 val parse_datatype = parse_wrap_options -- Parse.and_list1 parse_single_spec;
   809 
   810 fun parse_datatype_cmd lfp construct = parse_datatype >> datatype_cmd lfp construct;
   811 
   812 end;