src/HOL/Tools/Datatype/datatype_rep_proofs.ML
changeset 33968 f94fb13ecbb3
parent 33967 e191b400a8e0
child 33969 1e7ca47c6c3d
--- a/src/HOL/Tools/Datatype/datatype_rep_proofs.ML	Mon Nov 30 11:42:48 2009 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,747 +0,0 @@
-(*  Title:      HOL/Tools/datatype_rep_proofs.ML
-    Author:     Stefan Berghofer, TU Muenchen
-
-Definitional introduction of datatypes with proof of characteristic theorems:
-
- - injectivity of constructors
- - distinctness of constructors
- - induction theorem
-*)
-
-signature DATATYPE_REP_PROOFS =
-sig
-  val add_datatype : DatatypeAux.config -> string list -> (string list * binding * mixfix *
-    (binding * typ list * mixfix) list) list -> theory -> string list * theory
-  val datatype_cmd : string list -> (string list * binding * mixfix *
-    (binding * string list * mixfix) list) list -> theory -> theory
-end;
-
-structure DatatypeRepProofs : DATATYPE_REP_PROOFS =
-struct
-
-(** auxiliary **)
-
-open DatatypeAux;
-
-val (_ $ (_ $ (_ $ (distinct_f $ _) $ _))) = hd (prems_of distinct_lemma);
-
-val collect_simp = rewrite_rule [mk_meta_eq mem_Collect_eq];
-
-fun exh_thm_of (dt_info : info Symtab.table) tname =
-  #exhaust (the (Symtab.lookup dt_info tname));
-
-val node_name = @{type_name "Datatype.node"};
-val In0_name = @{const_name "Datatype.In0"};
-val In1_name = @{const_name "Datatype.In1"};
-val Scons_name = @{const_name "Datatype.Scons"};
-val Leaf_name = @{const_name "Datatype.Leaf"};
-val Numb_name = @{const_name "Datatype.Numb"};
-val Lim_name = @{const_name "Datatype.Lim"};
-val Suml_name = @{const_name "Sum_Type.Suml"};
-val Sumr_name = @{const_name "Sum_Type.Sumr"};
-
-val In0_inject = @{thm In0_inject};
-val In1_inject = @{thm In1_inject};
-val Scons_inject = @{thm Scons_inject};
-val Leaf_inject = @{thm Leaf_inject};
-val In0_eq = @{thm In0_eq};
-val In1_eq = @{thm In1_eq};
-val In0_not_In1 = @{thm In0_not_In1};
-val In1_not_In0 = @{thm In1_not_In0};
-val Lim_inject = @{thm Lim_inject};
-val Inl_inject = @{thm Inl_inject};
-val Inr_inject = @{thm Inr_inject};
-val Suml_inject = @{thm Suml_inject};
-val Sumr_inject = @{thm Sumr_inject};
-
-
-
-(** proof of characteristic theorems **)
-
-fun representation_proofs (config : config) (dt_info : info Symtab.table)
-      new_type_names descr sorts types_syntax constr_syntax case_names_induct thy =
-  let
-    val descr' = flat descr;
-    val big_name = space_implode "_" new_type_names;
-    val thy1 = Sign.add_path big_name thy;
-    val big_rec_name = big_name ^ "_rep_set";
-    val rep_set_names' =
-      (if length descr' = 1 then [big_rec_name] else
-        (map ((curry (op ^) (big_rec_name ^ "_")) o string_of_int)
-          (1 upto (length descr'))));
-    val rep_set_names = map (Sign.full_bname thy1) rep_set_names';
-
-    val tyvars = map (fn (_, (_, Ts, _)) => map dest_DtTFree Ts) (hd descr);
-    val leafTs' = get_nonrec_types descr' sorts;
-    val branchTs = get_branching_types descr' sorts;
-    val branchT = if null branchTs then HOLogic.unitT
-      else Balanced_Tree.make (fn (T, U) => Type ("+", [T, U])) branchTs;
-    val arities = remove (op =) 0 (get_arities descr');
-    val unneeded_vars =
-      subtract (op =) (List.foldr OldTerm.add_typ_tfree_names [] (leafTs' @ branchTs)) (hd tyvars);
-    val leafTs = leafTs' @ map (fn n => TFree (n, (the o AList.lookup (op =) sorts) n)) unneeded_vars;
-    val recTs = get_rec_types descr' sorts;
-    val (newTs, oldTs) = chop (length (hd descr)) recTs;
-    val sumT = if null leafTs then HOLogic.unitT
-      else Balanced_Tree.make (fn (T, U) => Type ("+", [T, U])) leafTs;
-    val Univ_elT = HOLogic.mk_setT (Type (node_name, [sumT, branchT]));
-    val UnivT = HOLogic.mk_setT Univ_elT;
-    val UnivT' = Univ_elT --> HOLogic.boolT;
-    val Collect = Const (@{const_name Collect}, UnivT' --> UnivT);
-
-    val In0 = Const (In0_name, Univ_elT --> Univ_elT);
-    val In1 = Const (In1_name, Univ_elT --> Univ_elT);
-    val Leaf = Const (Leaf_name, sumT --> Univ_elT);
-    val Lim = Const (Lim_name, (branchT --> Univ_elT) --> Univ_elT);
-
-    (* make injections needed for embedding types in leaves *)
-
-    fun mk_inj T' x =
-      let
-        fun mk_inj' T n i =
-          if n = 1 then x else
-          let val n2 = n div 2;
-              val Type (_, [T1, T2]) = T
-          in
-            if i <= n2 then
-              Const (@{const_name "Sum_Type.Inl"}, T1 --> T) $ (mk_inj' T1 n2 i)
-            else
-              Const (@{const_name "Sum_Type.Inr"}, T2 --> T) $ (mk_inj' T2 (n - n2) (i - n2))
-          end
-      in mk_inj' sumT (length leafTs) (1 + find_index (fn T'' => T'' = T') leafTs)
-      end;
-
-    (* make injections for constructors *)
-
-    fun mk_univ_inj ts = Balanced_Tree.access
-      {left = fn t => In0 $ t,
-        right = fn t => In1 $ t,
-        init =
-          if ts = [] then Const (@{const_name undefined}, Univ_elT)
-          else foldr1 (HOLogic.mk_binop Scons_name) ts};
-
-    (* function spaces *)
-
-    fun mk_fun_inj T' x =
-      let
-        fun mk_inj T n i =
-          if n = 1 then x else
-          let
-            val n2 = n div 2;
-            val Type (_, [T1, T2]) = T;
-            fun mkT U = (U --> Univ_elT) --> T --> Univ_elT
-          in
-            if i <= n2 then Const (Suml_name, mkT T1) $ mk_inj T1 n2 i
-            else Const (Sumr_name, mkT T2) $ mk_inj T2 (n - n2) (i - n2)
-          end
-      in mk_inj branchT (length branchTs) (1 + find_index (fn T'' => T'' = T') branchTs)
-      end;
-
-    fun mk_lim t Ts = fold_rev (fn T => fn t => Lim $ mk_fun_inj T (Abs ("x", T, t))) Ts t;
-
-    (************** generate introduction rules for representing set **********)
-
-    val _ = message config "Constructing representing sets ...";
-
-    (* make introduction rule for a single constructor *)
-
-    fun make_intr s n (i, (_, cargs)) =
-      let
-        fun mk_prem dt (j, prems, ts) =
-          (case strip_dtyp dt of
-            (dts, DtRec k) =>
-              let
-                val Ts = map (typ_of_dtyp descr' sorts) dts;
-                val free_t =
-                  app_bnds (mk_Free "x" (Ts ---> Univ_elT) j) (length Ts)
-              in (j + 1, list_all (map (pair "x") Ts,
-                  HOLogic.mk_Trueprop
-                    (Free (nth rep_set_names' k, UnivT') $ free_t)) :: prems,
-                mk_lim free_t Ts :: ts)
-              end
-          | _ =>
-              let val T = typ_of_dtyp descr' sorts dt
-              in (j + 1, prems, (Leaf $ mk_inj T (mk_Free "x" T j))::ts)
-              end);
-
-        val (_, prems, ts) = fold_rev mk_prem cargs (1, [], []);
-        val concl = HOLogic.mk_Trueprop
-          (Free (s, UnivT') $ mk_univ_inj ts n i)
-      in Logic.list_implies (prems, concl)
-      end;
-
-    val intr_ts = maps (fn ((_, (_, _, constrs)), rep_set_name) =>
-      map (make_intr rep_set_name (length constrs))
-        ((1 upto (length constrs)) ~~ constrs)) (descr' ~~ rep_set_names');
-
-    val ({raw_induct = rep_induct, intrs = rep_intrs, ...}, thy2) =
-      thy1
-      |> Sign.map_naming Name_Space.conceal
-      |> Inductive.add_inductive_global
-          {quiet_mode = #quiet config, verbose = false, alt_name = Binding.name big_rec_name,
-           coind = false, no_elim = true, no_ind = false, skip_mono = true, fork_mono = false}
-          (map (fn s => ((Binding.name s, UnivT'), NoSyn)) rep_set_names') []
-          (map (fn x => (Attrib.empty_binding, x)) intr_ts) []
-      ||> Sign.restore_naming thy1
-      ||> Theory.checkpoint;
-
-    (********************************* typedef ********************************)
-
-    val (typedefs, thy3) = thy2 |>
-      Sign.parent_path |>
-      fold_map (fn ((((name, mx), tvs), c), name') =>
-          Typedef.add_typedef false (SOME (Binding.name name')) (name, tvs, mx)
-            (Collect $ Const (c, UnivT')) NONE
-            (rtac exI 1 THEN rtac CollectI 1 THEN
-              QUIET_BREADTH_FIRST (has_fewer_prems 1)
-              (resolve_tac rep_intrs 1)))
-                (types_syntax ~~ tyvars ~~
-                  (take (length newTs) rep_set_names) ~~ new_type_names) ||>
-      Sign.add_path big_name;
-
-    (*********************** definition of constructors ***********************)
-
-    val big_rep_name = (space_implode "_" new_type_names) ^ "_Rep_";
-    val rep_names = map (curry op ^ "Rep_") new_type_names;
-    val rep_names' = map (fn i => big_rep_name ^ (string_of_int i))
-      (1 upto (length (flat (tl descr))));
-    val all_rep_names = map (Sign.intern_const thy3) rep_names @
-      map (Sign.full_bname thy3) rep_names';
-
-    (* isomorphism declarations *)
-
-    val iso_decls = map (fn (T, s) => (Binding.name s, T --> Univ_elT, NoSyn))
-      (oldTs ~~ rep_names');
-
-    (* constructor definitions *)
-
-    fun make_constr_def tname T n ((cname, cargs), (cname', mx)) (thy, defs, eqns, i) =
-      let
-        fun constr_arg dt (j, l_args, r_args) =
-          let val T = typ_of_dtyp descr' sorts dt;
-              val free_t = mk_Free "x" T j
-          in (case (strip_dtyp dt, strip_type T) of
-              ((_, DtRec m), (Us, U)) => (j + 1, free_t :: l_args, mk_lim
-                (Const (nth all_rep_names m, U --> Univ_elT) $
-                   app_bnds free_t (length Us)) Us :: r_args)
-            | _ => (j + 1, free_t::l_args, (Leaf $ mk_inj T free_t)::r_args))
-          end;
-
-        val (_, l_args, r_args) = fold_rev constr_arg cargs (1, [], []);
-        val constrT = (map (typ_of_dtyp descr' sorts) cargs) ---> T;
-        val abs_name = Sign.intern_const thy ("Abs_" ^ tname);
-        val rep_name = Sign.intern_const thy ("Rep_" ^ tname);
-        val lhs = list_comb (Const (cname, constrT), l_args);
-        val rhs = mk_univ_inj r_args n i;
-        val def = Logic.mk_equals (lhs, Const (abs_name, Univ_elT --> T) $ rhs);
-        val def_name = Long_Name.base_name cname ^ "_def";
-        val eqn = HOLogic.mk_Trueprop (HOLogic.mk_eq
-          (Const (rep_name, T --> Univ_elT) $ lhs, rhs));
-        val ([def_thm], thy') =
-          thy
-          |> Sign.add_consts_i [(cname', constrT, mx)]
-          |> (PureThy.add_defs false o map Thm.no_attributes) [(Binding.name def_name, def)];
-
-      in (thy', defs @ [def_thm], eqns @ [eqn], i + 1) end;
-
-    (* constructor definitions for datatype *)
-
-    fun dt_constr_defs ((((_, (_, _, constrs)), tname), T), constr_syntax)
-        (thy, defs, eqns, rep_congs, dist_lemmas) =
-      let
-        val _ $ (_ $ (cong_f $ _) $ _) = concl_of arg_cong;
-        val rep_const = cterm_of thy
-          (Const (Sign.intern_const thy ("Rep_" ^ tname), T --> Univ_elT));
-        val cong' =
-          Drule.standard (cterm_instantiate [(cterm_of thy cong_f, rep_const)] arg_cong);
-        val dist =
-          Drule.standard (cterm_instantiate [(cterm_of thy distinct_f, rep_const)] distinct_lemma);
-        val (thy', defs', eqns', _) = fold ((make_constr_def tname T) (length constrs))
-          (constrs ~~ constr_syntax) (Sign.add_path tname thy, defs, [], 1);
-      in
-        (Sign.parent_path thy', defs', eqns @ [eqns'],
-          rep_congs @ [cong'], dist_lemmas @ [dist])
-      end;
-
-    val (thy4, constr_defs, constr_rep_eqns, rep_congs, dist_lemmas) =
-      fold dt_constr_defs
-        (hd descr ~~ new_type_names ~~ newTs ~~ constr_syntax)
-        (thy3 |> Sign.add_consts_i iso_decls |> Sign.parent_path, [], [], [], []);
-
-
-    (*********** isomorphisms for new types (introduced by typedef) ***********)
-
-    val _ = message config "Proving isomorphism properties ...";
-
-    val newT_iso_axms = map (fn (_, td) =>
-      (collect_simp (#Abs_inverse td), #Rep_inverse td,
-       collect_simp (#Rep td))) typedefs;
-
-    val newT_iso_inj_thms = map (fn (_, td) =>
-      (collect_simp (#Abs_inject td) RS iffD1, #Rep_inject td RS iffD1)) typedefs;
-
-    (********* isomorphisms between existing types and "unfolded" types *******)
-
-    (*---------------------------------------------------------------------*)
-    (* isomorphisms are defined using primrec-combinators:                 *)
-    (* generate appropriate functions for instantiating primrec-combinator *)
-    (*                                                                     *)
-    (*   e.g.  dt_Rep_i = list_rec ... (%h t y. In1 (Scons (Leaf h) y))    *)
-    (*                                                                     *)
-    (* also generate characteristic equations for isomorphisms             *)
-    (*                                                                     *)
-    (*   e.g.  dt_Rep_i (cons h t) = In1 (Scons (dt_Rep_j h) (dt_Rep_i t)) *)
-    (*---------------------------------------------------------------------*)
-
-    fun make_iso_def k ks n (cname, cargs) (fs, eqns, i) =
-      let
-        val argTs = map (typ_of_dtyp descr' sorts) cargs;
-        val T = nth recTs k;
-        val rep_name = nth all_rep_names k;
-        val rep_const = Const (rep_name, T --> Univ_elT);
-        val constr = Const (cname, argTs ---> T);
-
-        fun process_arg ks' dt (i2, i2', ts, Ts) =
-          let
-            val T' = typ_of_dtyp descr' sorts dt;
-            val (Us, U) = strip_type T'
-          in (case strip_dtyp dt of
-              (_, DtRec j) => if j mem ks' then
-                  (i2 + 1, i2' + 1, ts @ [mk_lim (app_bnds
-                     (mk_Free "y" (Us ---> Univ_elT) i2') (length Us)) Us],
-                   Ts @ [Us ---> Univ_elT])
-                else
-                  (i2 + 1, i2', ts @ [mk_lim
-                     (Const (nth all_rep_names j, U --> Univ_elT) $
-                        app_bnds (mk_Free "x" T' i2) (length Us)) Us], Ts)
-            | _ => (i2 + 1, i2', ts @ [Leaf $ mk_inj T' (mk_Free "x" T' i2)], Ts))
-          end;
-
-        val (i2, i2', ts, Ts) = fold (process_arg ks) cargs (1, 1, [], []);
-        val xs = map (uncurry (mk_Free "x")) (argTs ~~ (1 upto (i2 - 1)));
-        val ys = map (uncurry (mk_Free "y")) (Ts ~~ (1 upto (i2' - 1)));
-        val f = list_abs_free (map dest_Free (xs @ ys), mk_univ_inj ts n i);
-
-        val (_, _, ts', _) = fold (process_arg []) cargs (1, 1, [], []);
-        val eqn = HOLogic.mk_Trueprop (HOLogic.mk_eq
-          (rep_const $ list_comb (constr, xs), mk_univ_inj ts' n i))
-
-      in (fs @ [f], eqns @ [eqn], i + 1) end;
-
-    (* define isomorphisms for all mutually recursive datatypes in list ds *)
-
-    fun make_iso_defs ds (thy, char_thms) =
-      let
-        val ks = map fst ds;
-        val (_, (tname, _, _)) = hd ds;
-        val {rec_rewrites, rec_names, ...} = the (Symtab.lookup dt_info tname);
-
-        fun process_dt (k, (tname, _, constrs)) (fs, eqns, isos) =
-          let
-            val (fs', eqns', _) =
-              fold (make_iso_def k ks (length constrs)) constrs (fs, eqns, 1);
-            val iso = (nth recTs k, nth all_rep_names k)
-          in (fs', eqns', isos @ [iso]) end;
-        
-        val (fs, eqns, isos) = fold process_dt ds ([], [], []);
-        val fTs = map fastype_of fs;
-        val defs = map (fn (rec_name, (T, iso_name)) => (Binding.name (Long_Name.base_name iso_name ^ "_def"),
-          Logic.mk_equals (Const (iso_name, T --> Univ_elT),
-            list_comb (Const (rec_name, fTs @ [T] ---> Univ_elT), fs)))) (rec_names ~~ isos);
-        val (def_thms, thy') =
-          apsnd Theory.checkpoint ((PureThy.add_defs false o map Thm.no_attributes) defs thy);
-
-        (* prove characteristic equations *)
-
-        val rewrites = def_thms @ (map mk_meta_eq rec_rewrites);
-        val char_thms' = map (fn eqn => Skip_Proof.prove_global thy' [] [] eqn
-          (fn _ => EVERY [rewrite_goals_tac rewrites, rtac refl 1])) eqns;
-
-      in (thy', char_thms' @ char_thms) end;
-
-    val (thy5, iso_char_thms) = apfst Theory.checkpoint (fold_rev make_iso_defs
-        (tl descr) (Sign.add_path big_name thy4, []));
-
-    (* prove isomorphism properties *)
-
-    fun mk_funs_inv thy thm =
-      let
-        val prop = Thm.prop_of thm;
-        val _ $ (_ $ ((S as Const (_, Type (_, [U, _]))) $ _ )) $
-          (_ $ (_ $ (r $ (a $ _)) $ _)) = Type.legacy_freeze prop;
-        val used = OldTerm.add_term_tfree_names (a, []);
-
-        fun mk_thm i =
-          let
-            val Ts = map (TFree o rpair HOLogic.typeS)
-              (Name.variant_list used (replicate i "'t"));
-            val f = Free ("f", Ts ---> U)
-          in Skip_Proof.prove_global thy [] [] (Logic.mk_implies
-            (HOLogic.mk_Trueprop (HOLogic.list_all
-               (map (pair "x") Ts, S $ app_bnds f i)),
-             HOLogic.mk_Trueprop (HOLogic.mk_eq (list_abs (map (pair "x") Ts,
-               r $ (a $ app_bnds f i)), f))))
-            (fn _ => EVERY [REPEAT_DETERM_N i (rtac ext 1),
-               REPEAT (etac allE 1), rtac thm 1, atac 1])
-          end
-      in map (fn r => r RS subst) (thm :: map mk_thm arities) end;
-
-    (* prove  inj dt_Rep_i  and  dt_Rep_i x : dt_rep_set_i *)
-
-    val fun_congs = map (fn T => make_elim (Drule.instantiate'
-      [SOME (ctyp_of thy5 T)] [] fun_cong)) branchTs;
-
-    fun prove_iso_thms ds (inj_thms, elem_thms) =
-      let
-        val (_, (tname, _, _)) = hd ds;
-        val induct = (#induct o the o Symtab.lookup dt_info) tname;
-
-        fun mk_ind_concl (i, _) =
-          let
-            val T = nth recTs i;
-            val Rep_t = Const (nth all_rep_names i, T --> Univ_elT);
-            val rep_set_name = nth rep_set_names i
-          in (HOLogic.all_const T $ Abs ("y", T, HOLogic.imp $
-                HOLogic.mk_eq (Rep_t $ mk_Free "x" T i, Rep_t $ Bound 0) $
-                  HOLogic.mk_eq (mk_Free "x" T i, Bound 0)),
-              Const (rep_set_name, UnivT') $ (Rep_t $ mk_Free "x" T i))
-          end;
-
-        val (ind_concl1, ind_concl2) = ListPair.unzip (map mk_ind_concl ds);
-
-        val rewrites = map mk_meta_eq iso_char_thms;
-        val inj_thms' = map snd newT_iso_inj_thms @
-          map (fn r => r RS @{thm injD}) inj_thms;
-
-        val inj_thm = Skip_Proof.prove_global thy5 [] []
-          (HOLogic.mk_Trueprop (mk_conj ind_concl1)) (fn _ => EVERY
-            [(indtac induct [] THEN_ALL_NEW ObjectLogic.atomize_prems_tac) 1,
-             REPEAT (EVERY
-               [rtac allI 1, rtac impI 1,
-                exh_tac (exh_thm_of dt_info) 1,
-                REPEAT (EVERY
-                  [hyp_subst_tac 1,
-                   rewrite_goals_tac rewrites,
-                   REPEAT (dresolve_tac [In0_inject, In1_inject] 1),
-                   (eresolve_tac [In0_not_In1 RS notE, In1_not_In0 RS notE] 1)
-                   ORELSE (EVERY
-                     [REPEAT (eresolve_tac (Scons_inject ::
-                        map make_elim [Leaf_inject, Inl_inject, Inr_inject]) 1),
-                      REPEAT (cong_tac 1), rtac refl 1,
-                      REPEAT (atac 1 ORELSE (EVERY
-                        [REPEAT (rtac ext 1),
-                         REPEAT (eresolve_tac (mp :: allE ::
-                           map make_elim (Suml_inject :: Sumr_inject ::
-                             Lim_inject :: inj_thms') @ fun_congs) 1),
-                         atac 1]))])])])]);
-
-        val inj_thms'' = map (fn r => r RS @{thm datatype_injI})
-                             (split_conj_thm inj_thm);
-
-        val elem_thm = 
-            Skip_Proof.prove_global thy5 [] [] (HOLogic.mk_Trueprop (mk_conj ind_concl2))
-              (fn _ =>
-               EVERY [(indtac induct [] THEN_ALL_NEW ObjectLogic.atomize_prems_tac) 1,
-                rewrite_goals_tac rewrites,
-                REPEAT ((resolve_tac rep_intrs THEN_ALL_NEW
-                  ((REPEAT o etac allE) THEN' ares_tac elem_thms)) 1)]);
-
-      in (inj_thms'' @ inj_thms, elem_thms @ (split_conj_thm elem_thm))
-      end;
-
-    val (iso_inj_thms_unfolded, iso_elem_thms) =
-      fold_rev prove_iso_thms (tl descr) ([], map #3 newT_iso_axms);
-    val iso_inj_thms = map snd newT_iso_inj_thms @
-      map (fn r => r RS @{thm injD}) iso_inj_thms_unfolded;
-
-    (* prove  dt_rep_set_i x --> x : range dt_Rep_i *)
-
-    fun mk_iso_t (((set_name, iso_name), i), T) =
-      let val isoT = T --> Univ_elT
-      in HOLogic.imp $ 
-        (Const (set_name, UnivT') $ mk_Free "x" Univ_elT i) $
-          (if i < length newTs then HOLogic.true_const
-           else HOLogic.mk_mem (mk_Free "x" Univ_elT i,
-             Const (@{const_name image}, isoT --> HOLogic.mk_setT T --> UnivT) $
-               Const (iso_name, isoT) $ Const (@{const_name UNIV}, HOLogic.mk_setT T)))
-      end;
-
-    val iso_t = HOLogic.mk_Trueprop (mk_conj (map mk_iso_t
-      (rep_set_names ~~ all_rep_names ~~ (0 upto (length descr' - 1)) ~~ recTs)));
-
-    (* all the theorems are proved by one single simultaneous induction *)
-
-    val range_eqs = map (fn r => mk_meta_eq (r RS @{thm range_ex1_eq}))
-      iso_inj_thms_unfolded;
-
-    val iso_thms = if length descr = 1 then [] else
-      drop (length newTs) (split_conj_thm
-        (Skip_Proof.prove_global thy5 [] [] iso_t (fn _ => EVERY
-           [(indtac rep_induct [] THEN_ALL_NEW ObjectLogic.atomize_prems_tac) 1,
-            REPEAT (rtac TrueI 1),
-            rewrite_goals_tac (mk_meta_eq choice_eq ::
-              symmetric (mk_meta_eq @{thm expand_fun_eq}) :: range_eqs),
-            rewrite_goals_tac (map symmetric range_eqs),
-            REPEAT (EVERY
-              [REPEAT (eresolve_tac ([rangeE, ex1_implies_ex RS exE] @
-                 maps (mk_funs_inv thy5 o #1) newT_iso_axms) 1),
-               TRY (hyp_subst_tac 1),
-               rtac (sym RS range_eqI) 1,
-               resolve_tac iso_char_thms 1])])));
-
-    val Abs_inverse_thms' =
-      map #1 newT_iso_axms @
-      map2 (fn r_inj => fn r => @{thm f_the_inv_into_f} OF [r_inj, r RS mp])
-        iso_inj_thms_unfolded iso_thms;
-
-    val Abs_inverse_thms = maps (mk_funs_inv thy5) Abs_inverse_thms';
-
-    (******************* freeness theorems for constructors *******************)
-
-    val _ = message config "Proving freeness of constructors ...";
-
-    (* prove theorem  Rep_i (Constr_j ...) = Inj_j ...  *)
-    
-    fun prove_constr_rep_thm eqn =
-      let
-        val inj_thms = map fst newT_iso_inj_thms;
-        val rewrites = @{thm o_def} :: constr_defs @ (map (mk_meta_eq o #2) newT_iso_axms)
-      in Skip_Proof.prove_global thy5 [] [] eqn (fn _ => EVERY
-        [resolve_tac inj_thms 1,
-         rewrite_goals_tac rewrites,
-         rtac refl 3,
-         resolve_tac rep_intrs 2,
-         REPEAT (resolve_tac iso_elem_thms 1)])
-      end;
-
-    (*--------------------------------------------------------------*)
-    (* constr_rep_thms and rep_congs are used to prove distinctness *)
-    (* of constructors.                                             *)
-    (*--------------------------------------------------------------*)
-
-    val constr_rep_thms = map (map prove_constr_rep_thm) constr_rep_eqns;
-
-    val dist_rewrites = map (fn (rep_thms, dist_lemma) =>
-      dist_lemma::(rep_thms @ [In0_eq, In1_eq, In0_not_In1, In1_not_In0]))
-        (constr_rep_thms ~~ dist_lemmas);
-
-    fun prove_distinct_thms dist_rewrites' (k, ts) =
-      let
-        fun prove [] = []
-          | prove (t :: ts) =
-              let
-                val dist_thm = Skip_Proof.prove_global thy5 [] [] t (fn _ =>
-                  EVERY [simp_tac (HOL_ss addsimps dist_rewrites') 1])
-              in dist_thm :: Drule.standard (dist_thm RS not_sym) :: prove ts end;
-      in prove ts end;
-
-    val distinct_thms = map2 (prove_distinct_thms)
-      dist_rewrites (DatatypeProp.make_distincts descr sorts);
-
-    (* prove injectivity of constructors *)
-
-    fun prove_constr_inj_thm rep_thms t =
-      let val inj_thms = Scons_inject :: (map make_elim
-        (iso_inj_thms @
-          [In0_inject, In1_inject, Leaf_inject, Inl_inject, Inr_inject,
-           Lim_inject, Suml_inject, Sumr_inject]))
-      in Skip_Proof.prove_global thy5 [] [] t (fn _ => EVERY
-        [rtac iffI 1,
-         REPEAT (etac conjE 2), hyp_subst_tac 2, rtac refl 2,
-         dresolve_tac rep_congs 1, dtac box_equals 1,
-         REPEAT (resolve_tac rep_thms 1),
-         REPEAT (eresolve_tac inj_thms 1),
-         REPEAT (ares_tac [conjI] 1 ORELSE (EVERY [REPEAT (rtac ext 1),
-           REPEAT (eresolve_tac (make_elim fun_cong :: inj_thms) 1),
-           atac 1]))])
-      end;
-
-    val constr_inject = map (fn (ts, thms) => map (prove_constr_inj_thm thms) ts)
-      ((DatatypeProp.make_injs descr sorts) ~~ constr_rep_thms);
-
-    val ((constr_inject', distinct_thms'), thy6) =
-      thy5
-      |> Sign.parent_path
-      |> store_thmss "inject" new_type_names constr_inject
-      ||>> store_thmss "distinct" new_type_names distinct_thms;
-
-    (*************************** induction theorem ****************************)
-
-    val _ = message config "Proving induction rule for datatypes ...";
-
-    val Rep_inverse_thms = (map (fn (_, iso, _) => iso RS subst) newT_iso_axms) @
-      (map (fn r => r RS @{thm the_inv_f_f} RS subst) iso_inj_thms_unfolded);
-    val Rep_inverse_thms' = map (fn r => r RS @{thm the_inv_f_f}) iso_inj_thms_unfolded;
-
-    fun mk_indrule_lemma ((i, _), T) (prems, concls) =
-      let
-        val Rep_t = Const (nth all_rep_names i, T --> Univ_elT) $
-          mk_Free "x" T i;
-
-        val Abs_t = if i < length newTs then
-            Const (Sign.intern_const thy6
-              ("Abs_" ^ (nth new_type_names i)), Univ_elT --> T)
-          else Const (@{const_name the_inv_into},
-              [HOLogic.mk_setT T, T --> Univ_elT, Univ_elT] ---> T) $
-            HOLogic.mk_UNIV T $ Const (nth all_rep_names i, T --> Univ_elT)
-
-      in (prems @ [HOLogic.imp $
-            (Const (nth rep_set_names i, UnivT') $ Rep_t) $
-              (mk_Free "P" (T --> HOLogic.boolT) (i + 1) $ (Abs_t $ Rep_t))],
-          concls @ [mk_Free "P" (T --> HOLogic.boolT) (i + 1) $ mk_Free "x" T i])
-      end;
-
-    val (indrule_lemma_prems, indrule_lemma_concls) =
-      fold mk_indrule_lemma (descr' ~~ recTs) ([], []);
-
-    val cert = cterm_of thy6;
-
-    val indrule_lemma = Skip_Proof.prove_global thy6 [] []
-      (Logic.mk_implies
-        (HOLogic.mk_Trueprop (mk_conj indrule_lemma_prems),
-         HOLogic.mk_Trueprop (mk_conj indrule_lemma_concls))) (fn _ => EVERY
-           [REPEAT (etac conjE 1),
-            REPEAT (EVERY
-              [TRY (rtac conjI 1), resolve_tac Rep_inverse_thms 1,
-               etac mp 1, resolve_tac iso_elem_thms 1])]);
-
-    val Ps = map head_of (HOLogic.dest_conj (HOLogic.dest_Trueprop (concl_of indrule_lemma)));
-    val frees = if length Ps = 1 then [Free ("P", snd (dest_Var (hd Ps)))] else
-      map (Free o apfst fst o dest_Var) Ps;
-    val indrule_lemma' = cterm_instantiate (map cert Ps ~~ map cert frees) indrule_lemma;
-
-    val dt_induct_prop = DatatypeProp.make_ind descr sorts;
-    val dt_induct = Skip_Proof.prove_global thy6 []
-      (Logic.strip_imp_prems dt_induct_prop) (Logic.strip_imp_concl dt_induct_prop)
-      (fn {prems, ...} => EVERY
-        [rtac indrule_lemma' 1,
-         (indtac rep_induct [] THEN_ALL_NEW ObjectLogic.atomize_prems_tac) 1,
-         EVERY (map (fn (prem, r) => (EVERY
-           [REPEAT (eresolve_tac Abs_inverse_thms 1),
-            simp_tac (HOL_basic_ss addsimps ((symmetric r)::Rep_inverse_thms')) 1,
-            DEPTH_SOLVE_1 (ares_tac [prem] 1 ORELSE etac allE 1)]))
-                (prems ~~ (constr_defs @ (map mk_meta_eq iso_char_thms))))]);
-
-    val ([dt_induct'], thy7) =
-      thy6
-      |> Sign.add_path big_name
-      |> PureThy.add_thms [((Binding.name "induct", dt_induct), [case_names_induct])]
-      ||> Sign.parent_path
-      ||> Theory.checkpoint;
-
-  in
-    ((constr_inject', distinct_thms', dt_induct'), thy7)
-  end;
-
-
-
-(** definitional introduction of datatypes **)
-
-fun gen_add_datatype prep_typ config new_type_names dts thy =
-  let
-    val _ = Theory.requires thy "Datatype" "datatype definitions";
-
-    (* this theory is used just for parsing *)
-    val tmp_thy = thy |>
-      Theory.copy |>
-      Sign.add_types (map (fn (tvs, tname, mx, _) =>
-        (tname, length tvs, mx)) dts);
-
-    val (tyvars, _, _, _)::_ = dts;
-    val (new_dts, types_syntax) = ListPair.unzip (map (fn (tvs, tname, mx, _) =>
-      let val full_tname = Sign.full_name tmp_thy (Binding.map_name (Syntax.type_name mx) tname)
-      in
-        (case duplicates (op =) tvs of
-          [] =>
-            if eq_set (op =) (tyvars, tvs) then ((full_tname, tvs), (tname, mx))
-            else error ("Mutually recursive datatypes must have same type parameters")
-        | dups => error ("Duplicate parameter(s) for datatype " ^ quote (Binding.str_of tname) ^
-            " : " ^ commas dups))
-      end) dts);
-    val dt_names = map fst new_dts;
-
-    val _ =
-      (case duplicates (op =) (map fst new_dts) @ duplicates (op =) new_type_names of
-        [] => ()
-      | dups => error ("Duplicate datatypes: " ^ commas dups));
-
-    fun prep_dt_spec (tvs, tname, mx, constrs) tname' (dts', constr_syntax, sorts, i) =
-      let
-        fun prep_constr (cname, cargs, mx') (constrs, constr_syntax', sorts') =
-          let
-            val (cargs', sorts'') = fold_map (prep_typ tmp_thy) cargs sorts';
-            val _ =
-              (case subtract (op =) tvs (fold (curry OldTerm.add_typ_tfree_names) cargs' []) of
-                [] => ()
-              | vs => error ("Extra type variables on rhs: " ^ commas vs))
-          in (constrs @ [(Sign.full_name_path tmp_thy tname'
-                  (Binding.map_name (Syntax.const_name mx') cname),
-                   map (dtyp_of_typ new_dts) cargs')],
-              constr_syntax' @ [(cname, mx')], sorts'')
-          end handle ERROR msg => cat_error msg
-           ("The error above occured in constructor " ^ quote (Binding.str_of cname) ^
-            " of datatype " ^ quote (Binding.str_of tname));
-
-        val (constrs', constr_syntax', sorts') =
-          fold prep_constr constrs ([], [], sorts)
-
-      in
-        case duplicates (op =) (map fst constrs') of
-           [] =>
-             (dts' @ [(i, (Sign.full_name tmp_thy (Binding.map_name (Syntax.type_name mx) tname),
-                map DtTFree tvs, constrs'))],
-              constr_syntax @ [constr_syntax'], sorts', i + 1)
-         | dups => error ("Duplicate constructors " ^ commas dups ^
-             " in datatype " ^ quote (Binding.str_of tname))
-      end;
-
-    val (dts', constr_syntax, sorts', i) =
-      fold2 prep_dt_spec dts new_type_names ([], [], [], 0);
-    val sorts = sorts' @ map (rpair (Sign.defaultS tmp_thy)) (subtract (op =) (map fst sorts') tyvars);
-    val dt_info = Datatype_Data.get_all thy;
-    val (descr, _) = unfold_datatypes tmp_thy dts' sorts dt_info dts' i;
-    val _ = check_nonempty descr handle (exn as Datatype_Empty s) =>
-      if #strict config then error ("Nonemptiness check failed for datatype " ^ s)
-      else raise exn;
-
-    val _ = message config ("Constructing datatype(s) " ^ commas_quote new_type_names);
-
-  in
-    thy
-    |> representation_proofs config dt_info new_type_names descr sorts
-        types_syntax constr_syntax (Datatype_Data.mk_case_names_induct (flat descr))
-    |-> (fn (inject, distinct, induct) => Datatype_Data.derive_datatype_props
-        config dt_names (SOME new_type_names) descr sorts
-        induct inject distinct)
-  end;
-
-val add_datatype = gen_add_datatype Datatype_Data.cert_typ;
-val datatype_cmd = snd ooo gen_add_datatype Datatype_Data.read_typ default_config;
-
-local
-
-structure P = OuterParse and K = OuterKeyword
-
-fun prep_datatype_decls args =
-  let
-    val names = map
-      (fn ((((NONE, _), t), _), _) => Binding.name_of t | ((((SOME t, _), _), _), _) => t) args;
-    val specs = map (fn ((((_, vs), t), mx), cons) =>
-      (vs, t, mx, map (fn ((x, y), z) => (x, y, z)) cons)) args;
-  in (names, specs) end;
-
-val parse_datatype_decl =
-  (Scan.option (P.$$$ "(" |-- P.name --| P.$$$ ")") -- P.type_args -- P.binding -- P.opt_infix --
-    (P.$$$ "=" |-- P.enum1 "|" (P.binding -- Scan.repeat P.typ -- P.opt_mixfix)));
-
-val parse_datatype_decls = P.and_list1 parse_datatype_decl >> prep_datatype_decls;
-
-in
-
-val _ =
-  OuterSyntax.command "datatype" "define inductive datatypes" K.thy_decl
-    (parse_datatype_decls >> (fn (names, specs) => Toplevel.theory (datatype_cmd names specs)));
-
-end;
-
-end;