diff --git a/src/Pure/Isar/toplevel.ML b/src/Pure/Isar/toplevel.ML
--- a/src/Pure/Isar/toplevel.ML
+++ b/src/Pure/Isar/toplevel.ML
@@ -1,793 +1,795 @@
 (*  Title:      Pure/Isar/toplevel.ML
     Author:     Markus Wenzel, TU Muenchen
 
 Isabelle/Isar toplevel transactions.
 *)
 
 signature TOPLEVEL =
 sig
   exception UNDEF
   type state
   val init_toplevel: unit -> state
   val theory_toplevel: theory -> state
   val is_toplevel: state -> bool
   val is_theory: state -> bool
   val is_proof: state -> bool
   val is_skipped_proof: state -> bool
   val level: state -> int
   val previous_theory_of: state -> theory option
   val context_of: state -> Proof.context
   val generic_theory_of: state -> generic_theory
   val theory_of: state -> theory
   val proof_of: state -> Proof.state
   val proof_position_of: state -> int
   val is_end_theory: state -> bool
   val end_theory: Position.T -> state -> theory
   val presentation_context: state -> Proof.context
   val presentation_state: Proof.context -> state
   val pretty_context: state -> Pretty.T list
   val pretty_state: state -> Pretty.T list
   val string_of_state: state -> string
   val pretty_abstract: state -> Pretty.T
   type transition
   val empty: transition
   val name_of: transition -> string
   val pos_of: transition -> Position.T
   val timing_of: transition -> Time.time
   val type_error: transition -> string
   val name: string -> transition -> transition
   val position: Position.T -> transition -> transition
   val markers: Input.source list -> transition -> transition
   val timing: Time.time -> transition -> transition
   val init_theory: (unit -> theory) -> transition -> transition
   val is_init: transition -> bool
   val modify_init: (unit -> theory) -> transition -> transition
   val exit: transition -> transition
   val keep: (state -> unit) -> transition -> transition
   val keep': (bool -> state -> unit) -> transition -> transition
   val keep_proof: (state -> unit) -> transition -> transition
   val ignored: Position.T -> transition
   val is_ignored: transition -> bool
   val malformed: Position.T -> string -> transition
   val generic_theory: (generic_theory -> generic_theory) -> transition -> transition
   val theory': (bool -> theory -> theory) -> transition -> transition
   val theory: (theory -> theory) -> transition -> transition
   val begin_local_theory: bool -> (theory -> local_theory) -> transition -> transition
   val end_local_theory: transition -> transition
   val open_target: (generic_theory -> local_theory) -> transition -> transition
   val close_target: transition -> transition
   val local_theory': (bool * Position.T) option -> (xstring * Position.T) option ->
     (bool -> local_theory -> local_theory) -> transition -> transition
   val local_theory: (bool * Position.T) option -> (xstring * Position.T) option ->
     (local_theory -> local_theory) -> transition -> transition
   val present_local_theory: (xstring * Position.T) option -> (state -> unit) ->
     transition -> transition
   val local_theory_to_proof': (bool * Position.T) option -> (xstring * Position.T) option ->
     (bool -> local_theory -> Proof.state) -> transition -> transition
   val local_theory_to_proof: (bool * Position.T) option -> (xstring * Position.T) option ->
     (local_theory -> Proof.state) -> transition -> transition
   val theory_to_proof: (theory -> Proof.state) -> transition -> transition
   val end_proof: (bool -> Proof.state -> Proof.context) -> transition -> transition
   val forget_proof: transition -> transition
   val proofs': (bool -> Proof.state -> Proof.state Seq.result Seq.seq) -> transition -> transition
   val proof': (bool -> Proof.state -> Proof.state) -> transition -> transition
   val proofs: (Proof.state -> Proof.state Seq.result Seq.seq) -> transition -> transition
   val proof: (Proof.state -> Proof.state) -> transition -> transition
   val actual_proof: (Proof_Node.T -> Proof_Node.T) -> transition -> transition
   val skip_proof: (unit -> unit) -> transition -> transition
   val skip_proof_open: transition -> transition
   val skip_proof_close: transition -> transition
   val exec_id: Document_ID.exec -> transition -> transition
   val setmp_thread_position: transition -> ('a -> 'b) -> 'a -> 'b
   val add_hook: (transition -> state -> state -> unit) -> unit
   val transition: bool -> transition -> state -> state * (exn * string) option
   val command_errors: bool -> transition -> state -> Runtime.error list * state option
   val command_exception: bool -> transition -> state -> state
   val reset_theory: state -> state option
   val reset_proof: state -> state option
   val reset_notepad: state -> state option
   val fork_presentation: transition -> transition * transition
   type result
   val join_results: result -> (transition * state) list
   val element_result: Keyword.keywords -> transition Thy_Element.element -> state -> result * state
 end;
 
 structure Toplevel: TOPLEVEL =
 struct
 
 (** toplevel state **)
 
 exception UNDEF = Runtime.UNDEF;
 
 
 (* datatype node *)
 
 datatype node =
   Toplevel
     (*toplevel outside of theory body*) |
   Theory of generic_theory
     (*global or local theory*) |
   Proof of Proof_Node.T * ((Proof.context -> generic_theory) * generic_theory)
     (*proof node, finish, original theory*) |
   Skipped_Proof of int * (generic_theory * generic_theory);
     (*proof depth, resulting theory, original theory*)
 
 val theory_node = fn Theory gthy => SOME gthy | _ => NONE;
 val proof_node = fn Proof (prf, _) => SOME prf | _ => NONE;
 val skipped_proof_node = fn Skipped_Proof _ => true | _ => false;
 
 fun cases_node f _ _ Toplevel = f ()
   | cases_node _ g _ (Theory gthy) = g gthy
   | cases_node _ _ h (Proof (prf, _)) = h (Proof_Node.current prf)
   | cases_node _ g _ (Skipped_Proof (_, (gthy, _))) = g gthy;
 
 fun cases_proper_node g h = cases_node (fn () => raise UNDEF) g h;
 
 val get_theory = cases_node (K NONE) (SOME o Context.theory_of) (SOME o Proof.theory_of);
 
 
 (* datatype state *)
 
 type node_presentation = node * Proof.context;
 
 fun init_presentation () =
   Proof_Context.init_global (Theory.get_pure_bootstrap ());
 
 fun node_presentation node =
   (node, cases_node init_presentation Context.proof_of Proof.context_of node);
 
 
 datatype state =
   State of node_presentation * theory option;
     (*current node with presentation context, previous theory*)
 
 fun node_of (State ((node, _), _)) = node;
 fun previous_theory_of (State (_, prev_thy)) = prev_thy;
 
 fun init_toplevel () = State (node_presentation Toplevel, NONE);
 fun theory_toplevel thy = State (node_presentation (Theory (Context.Theory thy)), NONE);
 
 
 fun level state =
   (case node_of state of
     Toplevel => 0
   | Theory _ => 0
   | Proof (prf, _) => Proof.level (Proof_Node.current prf)
   | Skipped_Proof (d, _) => d + 1);   (*different notion of proof depth!*)
 
 fun str_of_state state =
   (case node_of state of
     Toplevel =>
       (case previous_theory_of state of
         NONE => "at top level"
       | SOME thy => "at top level, result theory " ^ quote (Context.theory_name thy))
   | Theory (Context.Theory _) => "in theory mode"
   | Theory (Context.Proof _) => "in local theory mode"
   | Proof _ => "in proof mode"
   | Skipped_Proof _ => "in skipped proof mode");
 
 
 (* current node *)
 
 fun is_toplevel state = (case node_of state of Toplevel => true | _ => false);
 
 fun is_theory state =
   not (is_toplevel state) andalso is_some (theory_node (node_of state));
 
 fun is_proof state =
   not (is_toplevel state) andalso is_some (proof_node (node_of state));
 
 fun is_skipped_proof state =
   not (is_toplevel state) andalso skipped_proof_node (node_of state);
 
 fun proper_node_of state = if is_toplevel state then raise UNDEF else node_of state;
 fun proper_node_case f g state = cases_proper_node f g (proper_node_of state);
 
 val context_of = proper_node_case Context.proof_of Proof.context_of;
 val generic_theory_of = proper_node_case I (Context.Proof o Proof.context_of);
 val theory_of = proper_node_case Context.theory_of Proof.theory_of;
 val proof_of = proper_node_case (fn _ => error "No proof state") I;
 
 fun proof_position_of state =
   (case proper_node_of state of
     Proof (prf, _) => Proof_Node.position prf
   | _ => ~1);
 
 fun is_end_theory (State ((Toplevel, _), SOME _)) = true
   | is_end_theory _ = false;
 
 fun end_theory _ (State ((Toplevel, _), SOME thy)) = thy
   | end_theory pos _ = error ("Malformed theory" ^ Position.here pos);
 
 
 (* presentation context *)
 
 structure Presentation_State = Proof_Data
 (
   type T = state option;
   fun init _ = NONE;
 );
 
 fun presentation_context0 (State ((_, pr_ctxt), _)) = pr_ctxt;
 
 fun presentation_context (state as State (current, _)) =
   presentation_context0 state
   |> Presentation_State.put (SOME (State (current, NONE)));
 
 fun presentation_state ctxt =
   (case Presentation_State.get ctxt of
     NONE => State (node_presentation (Theory (Context.Proof ctxt)), NONE)
   | SOME state => state);
 
 
 (* print state *)
 
 fun pretty_context state =
   if is_toplevel state then []
   else
     let
       val gthy =
         (case node_of state of
           Toplevel => raise Match
         | Theory gthy => gthy
         | Proof (_, (_, gthy)) => gthy
         | Skipped_Proof (_, (_, gthy)) => gthy);
       val lthy = Context.cases Named_Target.theory_init I gthy;
     in Local_Theory.pretty lthy end;
 
 fun pretty_state state =
   (case node_of state of
     Toplevel => []
   | Theory _ => []
   | Proof (prf, _) => Proof.pretty_state (Proof_Node.current prf)
   | Skipped_Proof (d, _) => [Pretty.str ("skipped proof: depth " ^ string_of_int d)]);
 
 val string_of_state = pretty_state #> Pretty.chunks #> Pretty.string_of;
 
 fun pretty_abstract state = Pretty.str ("<Isar " ^ str_of_state state ^ ">");
 
 val _ = ML_system_pp (fn _ => fn _ => Pretty.to_polyml o pretty_abstract);
 
 
 
 (** toplevel transitions **)
 
 (* primitive transitions *)
 
 datatype trans =
   (*init theory*)
   Init of unit -> theory |
   (*formal exit of theory*)
   Exit |
   (*peek at state*)
   Keep of bool -> state -> unit |
   (*node transaction and presentation*)
   Transaction of (bool -> node -> node_presentation) * (state -> unit);
 
 local
 
 exception FAILURE of state * exn;
 
 fun apply f g node =
   let
     val node_pr = node_presentation node;
     val context = cases_proper_node I (Context.Proof o Proof.context_of) node;
     fun state_error e node_pr' = (State (node_pr', get_theory node), e);
 
     val (result, err) =
       node
       |> Runtime.controlled_execution (SOME context) f
       |> state_error NONE
       handle exn => state_error (SOME exn) node_pr;
   in
     (case err of
       NONE => tap g result
     | SOME exn => raise FAILURE (result, exn))
   end;
 
 fun apply_tr int trans state =
   (case (trans, node_of state) of
     (Init f, Toplevel) =>
       Runtime.controlled_execution NONE (fn () =>
         State (node_presentation (Theory (Context.Theory (f ()))), NONE)) ()
   | (Exit, node as Theory (Context.Theory thy)) =>
       let
         val State ((node', pr_ctxt), _) =
           node |> apply
-            (fn _ => node_presentation (Theory (Context.Theory (Theory.end_theory thy))))
+            (fn _ =>
+              node_presentation
+                (Theory (Context.Theory (tap Thm.expose_theory (Theory.end_theory thy)))))
             (K ());
       in State ((Toplevel, pr_ctxt), get_theory node') end
   | (Keep f, node) =>
       Runtime.controlled_execution (try generic_theory_of state)
         (fn () => (f int state; State (node_presentation node, previous_theory_of state))) ()
   | (Transaction _, Toplevel) => raise UNDEF
   | (Transaction (f, g), node) => apply (fn x => f int x) g node
   | _ => raise UNDEF);
 
 fun apply_union _ [] state = raise FAILURE (state, UNDEF)
   | apply_union int (tr :: trs) state =
       apply_union int trs state
         handle Runtime.UNDEF => apply_tr int tr state
           | FAILURE (alt_state, UNDEF) => apply_tr int tr alt_state
           | exn as FAILURE _ => raise exn
           | exn => raise FAILURE (state, exn);
 
 fun apply_markers name markers (state as State ((node, pr_ctxt), prev_thy)) =
   let
     val state' =
       Runtime.controlled_execution (try generic_theory_of state)
         (fn () => State ((node, fold (Document_Marker.evaluate name) markers pr_ctxt), prev_thy)) ();
   in (state', NONE) end
   handle exn => (state, SOME exn);
 
 in
 
 fun apply_trans int name markers trans state =
   (apply_union int trans state |> apply_markers name markers)
   handle FAILURE (alt_state, exn) => (alt_state, SOME exn) | exn => (state, SOME exn);
 
 end;
 
 
 (* datatype transition *)
 
 datatype transition = Transition of
  {name: string,               (*command name*)
   pos: Position.T,            (*source position*)
   markers: Input.source list, (*semantic document markers*)
   timing: Time.time,          (*prescient timing information*)
   trans: trans list};         (*primitive transitions (union)*)
 
 fun make_transition (name, pos, markers, timing, trans) =
   Transition {name = name, pos = pos, markers = markers, timing = timing, trans = trans};
 
 fun map_transition f (Transition {name, pos, markers, timing, trans}) =
   make_transition (f (name, pos, markers, timing, trans));
 
 val empty = make_transition ("", Position.none, [], Time.zeroTime, []);
 
 
 (* diagnostics *)
 
 fun name_of (Transition {name, ...}) = name;
 fun pos_of (Transition {pos, ...}) = pos;
 fun timing_of (Transition {timing, ...}) = timing;
 
 fun command_msg msg tr =
   msg ^ "command " ^ quote (Markup.markup Markup.keyword1 (name_of tr)) ^
     Position.here (pos_of tr);
 
 fun at_command tr = command_msg "At " tr;
 fun type_error tr = command_msg "Bad context for " tr;
 
 
 (* modify transitions *)
 
 fun name name = map_transition (fn (_, pos, markers, timing, trans) =>
   (name, pos, markers, timing, trans));
 
 fun position pos = map_transition (fn (name, _, markers, timing, trans) =>
   (name, pos, markers, timing, trans));
 
 fun markers markers = map_transition (fn (name, pos, _, timing, trans) =>
   (name, pos, markers, timing, trans));
 
 fun timing timing = map_transition (fn (name, pos, markers, _, trans) =>
   (name, pos, markers, timing, trans));
 
 fun add_trans tr = map_transition (fn (name, pos, markers, timing, trans) =>
   (name, pos, markers, timing, tr :: trans));
 
 val reset_trans = map_transition (fn (name, pos, markers, timing, _) =>
   (name, pos, markers, timing, []));
 
 
 (* basic transitions *)
 
 fun init_theory f = add_trans (Init f);
 
 fun is_init (Transition {trans = [Init _], ...}) = true
   | is_init _ = false;
 
 fun modify_init f tr = if is_init tr then init_theory f (reset_trans tr) else tr;
 
 val exit = add_trans Exit;
 val keep' = add_trans o Keep;
 
 fun present_transaction f g = add_trans (Transaction (f, g));
 fun transaction f = present_transaction f (K ());
 fun transaction0 f = present_transaction (node_presentation oo f) (K ());
 
 fun keep f = add_trans (Keep (fn _ => f));
 
 fun keep_proof f =
   keep (fn st =>
     if is_proof st then f st
     else if is_skipped_proof st then ()
     else warning "No proof state");
 
 fun ignored pos = empty |> name "<ignored>" |> position pos |> keep (fn _ => ());
 fun is_ignored tr = name_of tr = "<ignored>";
 
 fun malformed pos msg =
   empty |> name "<malformed>" |> position pos |> keep (fn _ => error msg);
 
 
 (* theory transitions *)
 
 fun generic_theory f = transaction (fn _ =>
   (fn Theory gthy => node_presentation (Theory (f gthy))
     | _ => raise UNDEF));
 
 fun theory' f = transaction (fn int =>
   (fn Theory (Context.Theory thy) =>
       let val thy' = thy
         |> Sign.new_group
         |> f int
         |> Sign.reset_group;
       in node_presentation (Theory (Context.Theory thy')) end
     | _ => raise UNDEF));
 
 fun theory f = theory' (K f);
 
 fun begin_local_theory begin f = transaction (fn _ =>
   (fn Theory (Context.Theory thy) =>
         let
           val lthy = f thy;
           val gthy = if begin then Context.Proof lthy else Context.Theory (Named_Target.exit lthy);
           val _ =
             (case Local_Theory.pretty lthy of
               [] => ()
             | prts => Output.state (Pretty.string_of (Pretty.chunks prts)));
         in (Theory gthy, lthy) end
     | _ => raise UNDEF));
 
 val end_local_theory = transaction (fn _ =>
   (fn Theory (Context.Proof lthy) => (Theory (Context.Theory (Named_Target.exit lthy)), lthy)
     | _ => raise UNDEF));
 
 fun open_target f = transaction0 (fn _ =>
   (fn Theory gthy =>
         let val lthy = f gthy
         in Theory (Context.Proof lthy) end
     | _ => raise UNDEF));
 
 val close_target = transaction (fn _ =>
   (fn Theory (Context.Proof lthy) =>
         (case try Local_Theory.close_target lthy of
           SOME ctxt' =>
             let
               val gthy' =
                 if can Local_Theory.assert ctxt'
                 then Context.Proof ctxt'
                 else Context.Theory (Proof_Context.theory_of ctxt');
             in (Theory gthy', lthy) end
         | NONE => raise UNDEF)
     | _ => raise UNDEF));
 
 fun restricted_context (SOME (strict, scope)) =
       Proof_Context.map_naming (Name_Space.restricted strict scope)
   | restricted_context NONE = I;
 
 fun local_theory' restricted target f = present_transaction (fn int =>
   (fn Theory gthy =>
         let
           val (finish, lthy) = Named_Target.switch target gthy;
           val lthy' = lthy
             |> restricted_context restricted
             |> Local_Theory.new_group
             |> f int
             |> Local_Theory.reset_group;
         in (Theory (finish lthy'), lthy') end
     | _ => raise UNDEF))
   (K ());
 
 fun local_theory restricted target f = local_theory' restricted target (K f);
 
 fun present_local_theory target = present_transaction (fn _ =>
   (fn Theory gthy =>
         let val (finish, lthy) = Named_Target.switch target gthy;
         in (Theory (finish lthy), lthy) end
     | _ => raise UNDEF));
 
 
 (* proof transitions *)
 
 fun end_proof f = transaction (fn int =>
   (fn Proof (prf, (finish, _)) =>
         let val state = Proof_Node.current prf in
           if can (Proof.assert_bottom true) state then
             let
               val ctxt' = f int state;
               val gthy' = finish ctxt';
             in (Theory gthy', ctxt') end
           else raise UNDEF
         end
     | Skipped_Proof (0, (gthy, _)) => node_presentation (Theory gthy)
     | _ => raise UNDEF));
 
 local
 
 fun begin_proof init_proof = transaction0 (fn int =>
   (fn Theory gthy =>
     let
       val (finish, prf) = init_proof int gthy;
       val document = Options.default_string "document";
       val skip = (document = "" orelse document = "false") andalso Goal.skip_proofs_enabled ();
       val schematic_goal = try Proof.schematic_goal prf;
       val _ =
         if skip andalso schematic_goal = SOME true then
           warning "Cannot skip proof of schematic goal statement"
         else ();
     in
       if skip andalso schematic_goal = SOME false then
         Skipped_Proof (0, (finish (Proof.global_skip_proof true prf), gthy))
       else Proof (Proof_Node.init prf, (finish, gthy))
     end
   | _ => raise UNDEF));
 
 in
 
 fun local_theory_to_proof' restricted target f = begin_proof
   (fn int => fn gthy =>
     let
       val (finish, lthy) = Named_Target.switch target gthy;
       val prf = lthy
         |> restricted_context restricted
         |> Local_Theory.new_group
         |> f int;
     in (finish o Local_Theory.reset_group, prf) end);
 
 fun local_theory_to_proof restricted target f =
   local_theory_to_proof' restricted target (K f);
 
 fun theory_to_proof f = begin_proof
   (fn _ => fn gthy =>
     (Context.Theory o Sign.reset_group o Sign.change_check o Proof_Context.theory_of,
       (case gthy of
         Context.Theory thy => f (Sign.new_group thy)
       | _ => raise UNDEF)));
 
 end;
 
 val forget_proof = transaction0 (fn _ =>
   (fn Proof (prf, (_, orig_gthy)) =>
         if Proof.is_notepad (Proof_Node.current prf) then raise UNDEF
         else Theory orig_gthy
     | Skipped_Proof (_, (_, orig_gthy)) => Theory orig_gthy
     | _ => raise UNDEF));
 
 fun proofs' f = transaction0 (fn int =>
   (fn Proof (prf, x) => Proof (Proof_Node.applys (f int) prf, x)
     | skip as Skipped_Proof _ => skip
     | _ => raise UNDEF));
 
 fun proof' f = proofs' ((Seq.single o Seq.Result) oo f);
 val proofs = proofs' o K;
 val proof = proof' o K;
 
 
 (* skipped proofs *)
 
 fun actual_proof f = transaction0 (fn _ =>
   (fn Proof (prf, x) => Proof (f prf, x)
     | _ => raise UNDEF));
 
 fun skip_proof f = transaction0 (fn _ =>
   (fn skip as Skipped_Proof _ => (f (); skip)
     | _ => raise UNDEF));
 
 val skip_proof_open = transaction0 (fn _ =>
   (fn Skipped_Proof (d, x) => Skipped_Proof (d + 1, x)
     | _ => raise UNDEF));
 
 val skip_proof_close = transaction0 (fn _ =>
   (fn Skipped_Proof (0, (gthy, _)) => Theory gthy
     | Skipped_Proof (d, x) => Skipped_Proof (d - 1, x)
     | _ => raise UNDEF));
 
 
 
 (** toplevel transactions **)
 
 (* runtime position *)
 
 fun exec_id id (tr as Transition {pos, ...}) =
   position (Position.put_id (Document_ID.print id) pos) tr;
 
 fun setmp_thread_position (Transition {pos, ...}) f x =
   Position.setmp_thread_data pos f x;
 
 
 (* post-transition hooks *)
 
 local
   val hooks =
     Synchronized.var "Toplevel.hooks" ([]: (transition -> state -> state -> unit) list);
 in
 
 fun add_hook hook = Synchronized.change hooks (cons hook);
 fun get_hooks () = Synchronized.value hooks;
 
 end;
 
 
 (* apply transitions *)
 
 local
 
 fun app int (tr as Transition {name, markers, trans, ...}) =
   setmp_thread_position tr
     (Timing.protocol (name_of tr) (pos_of tr) (apply_trans int name markers trans)
       ##> Option.map (fn UNDEF => ERROR (type_error tr) | exn => exn));
 
 in
 
 fun transition int tr st =
   let
     val (st', opt_err) =
       Context.setmp_generic_context (try (Context.Proof o presentation_context0) st)
         (fn () => app int tr st) ();
     val opt_err' = opt_err |> Option.map
       (fn Runtime.EXCURSION_FAIL exn_info => exn_info
         | exn => (Runtime.exn_context (try context_of st) exn, at_command tr));
     val _ = get_hooks () |> List.app (fn f => (try (fn () => f tr st st') (); ()));
   in (st', opt_err') end;
 
 end;
 
 
 (* managed commands *)
 
 fun command_errors int tr st =
   (case transition int tr st of
     (st', NONE) => ([], SOME st')
   | (_, SOME (exn, _)) => (Runtime.exn_messages exn, NONE));
 
 fun command_exception int tr st =
   (case transition int tr st of
     (st', NONE) => st'
   | (_, SOME (exn, info)) =>
       if Exn.is_interrupt exn then Exn.reraise exn
       else raise Runtime.EXCURSION_FAIL (exn, info));
 
 val command = command_exception false;
 
 
 (* reset state *)
 
 local
 
 fun reset_state check trans st =
   if check st then NONE
   else #2 (command_errors false (trans empty) st);
 
 in
 
 val reset_theory = reset_state is_theory forget_proof;
 
 val reset_proof =
   reset_state is_proof
     (transaction0 (fn _ =>
       (fn Theory gthy => Skipped_Proof (0, (gthy, gthy))
         | _ => raise UNDEF)));
 
 val reset_notepad =
   reset_state
     (fn st =>
       (case try proof_of st of
         SOME state => not (Proof.is_notepad state) orelse can Proof.end_notepad state
       | NONE => true))
     (proof Proof.reset_notepad);
 
 end;
 
 
 (* scheduled proof result *)
 
 datatype result =
   Result of transition * state |
   Result_List of result list |
   Result_Future of result future;
 
 fun join_results (Result x) = [x]
   | join_results (Result_List xs) = maps join_results xs
   | join_results (Result_Future x) = join_results (Future.join x);
 
 local
 
 structure Result = Proof_Data
 (
   type T = result;
   fun init _ = Result_List [];
 );
 
 val get_result = Result.get o Proof.context_of;
 val put_result = Proof.map_context o Result.put;
 
 fun timing_estimate elem =
   let val trs = tl (Thy_Element.flat_element elem)
   in fold (fn tr => fn t => timing_of tr + t) trs Time.zeroTime end;
 
 fun future_proofs_enabled estimate st =
   (case try proof_of st of
     NONE => false
   | SOME state =>
       not (Proofterm.proofs_enabled ()) andalso
       not (Proof.is_relevant state) andalso
        (if can (Proof.assert_bottom true) state
         then Future.proofs_enabled 1
         else Future.proofs_enabled 2 orelse Future.proofs_enabled_timing estimate));
 
 val empty_markers = markers [];
 val empty_trans = reset_trans #> keep (K ());
 
 in
 
 fun fork_presentation tr = (tr |> empty_markers, tr |> empty_trans);
 
 fun atom_result keywords tr st =
   let
     val st' =
       if Future.proofs_enabled 1 andalso Keyword.is_diag keywords (name_of tr) then
         let
           val (tr1, tr2) = fork_presentation tr;
           val _ =
             Execution.fork {name = "Toplevel.diag", pos = pos_of tr, pri = ~1}
               (fn () => command tr1 st);
         in command tr2 st end
       else command tr st;
   in (Result (tr, st'), st') end;
 
 fun element_result keywords (Thy_Element.Element (tr, NONE)) st = atom_result keywords tr st
   | element_result keywords (elem as Thy_Element.Element (head_tr, SOME element_rest)) st =
       let
         val (head_result, st') = atom_result keywords head_tr st;
         val (body_elems, end_tr) = element_rest;
         val estimate = timing_estimate elem;
       in
         if not (future_proofs_enabled estimate st')
         then
           let
             val proof_trs = maps Thy_Element.flat_element body_elems @ [end_tr];
             val (proof_results, st'') = fold_map (atom_result keywords) proof_trs st';
           in (Result_List (head_result :: proof_results), st'') end
         else
           let
             val (end_tr1, end_tr2) = fork_presentation end_tr;
 
             val finish = Context.Theory o Proof_Context.theory_of;
 
             val future_proof =
               Proof.future_proof (fn state =>
                 Execution.fork
                   {name = "Toplevel.future_proof", pos = pos_of head_tr, pri = ~1}
                   (fn () =>
                     let
                       val State ((Proof (prf, (_, orig_gthy)), _), prev_thy) = st';
                       val node' = Proof (Proof_Node.apply (K state) prf, (finish, orig_gthy));
                       val (results, result_state) =
                         State (node_presentation node', prev_thy)
                         |> fold_map (element_result keywords) body_elems ||> command end_tr1;
                     in (Result_List results, presentation_context0 result_state) end))
               #> (fn (res, state') => state' |> put_result (Result_Future res));
 
             val forked_proof =
               proof (future_proof #>
                 (fn state => state |> Proof.local_done_proof |> put_result (get_result state))) o
               end_proof (fn _ => future_proof #>
                 (fn state => state |> Proof.global_done_proof |> Result.put (get_result state)));
 
             val st'' = st' |> command (head_tr |> reset_trans |> forked_proof);
             val end_st = st'' |> command end_tr2;
             val end_result = Result (end_tr, end_st);
             val result =
               Result_List [head_result, Result.get (presentation_context0 st''), end_result];
           in (result, end_st) end
       end;
 
 end;
 
 end;
 
 structure Local_Theory : LOCAL_THEORY = struct open Local_Theory; end;
diff --git a/src/Pure/more_thm.ML b/src/Pure/more_thm.ML
--- a/src/Pure/more_thm.ML
+++ b/src/Pure/more_thm.ML
@@ -1,755 +1,755 @@
 (*  Title:      Pure/more_thm.ML
     Author:     Makarius
 
 Further operations on type ctyp/cterm/thm, outside the inference kernel.
 *)
 
 infix aconvc;
 
 signature BASIC_THM =
 sig
   include BASIC_THM
   val show_consts: bool Config.T
   val show_hyps: bool Config.T
   val show_tags: bool Config.T
   structure Ctermtab: TABLE
   structure Thmtab: TABLE
   val aconvc: cterm * cterm -> bool
   type attribute = Context.generic * thm -> Context.generic option * thm option
 end;
 
 signature THM =
 sig
   include THM
   structure Ctermtab: TABLE
   structure Thmtab: TABLE
   val eq_ctyp: ctyp * ctyp -> bool
   val aconvc: cterm * cterm -> bool
   val add_tvars: thm -> ctyp list -> ctyp list
   val add_frees: thm -> cterm list -> cterm list
   val add_vars: thm -> cterm list -> cterm list
   val dest_funT: ctyp -> ctyp * ctyp
   val strip_type: ctyp -> ctyp list * ctyp
   val all_name: Proof.context -> string * cterm -> cterm -> cterm
   val all: Proof.context -> cterm -> cterm -> cterm
   val mk_binop: cterm -> cterm -> cterm -> cterm
   val dest_binop: cterm -> cterm * cterm
   val dest_implies: cterm -> cterm * cterm
   val dest_equals: cterm -> cterm * cterm
   val dest_equals_lhs: cterm -> cterm
   val dest_equals_rhs: cterm -> cterm
   val lhs_of: thm -> cterm
   val rhs_of: thm -> cterm
   val fast_term_ord: cterm ord
   val term_ord: cterm ord
   val thm_ord: thm ord
   val cterm_cache: (cterm -> 'a) -> cterm -> 'a
   val thm_cache: (thm -> 'a) -> thm -> 'a
   val is_reflexive: thm -> bool
   val eq_thm: thm * thm -> bool
   val eq_thm_prop: thm * thm -> bool
   val eq_thm_strict: thm * thm -> bool
   val equiv_thm: theory -> thm * thm -> bool
   val class_triv: theory -> class -> thm
   val of_sort: ctyp * sort -> thm list
   val is_dummy: thm -> bool
   val add_thm: thm -> thm list -> thm list
   val del_thm: thm -> thm list -> thm list
   val merge_thms: thm list * thm list -> thm list
   val full_rules: thm Item_Net.T
   val intro_rules: thm Item_Net.T
   val elim_rules: thm Item_Net.T
   val declare_hyps: cterm -> Proof.context -> Proof.context
   val assume_hyps: cterm -> Proof.context -> thm * Proof.context
   val unchecked_hyps: Proof.context -> Proof.context
   val restore_hyps: Proof.context -> Proof.context -> Proof.context
   val undeclared_hyps: Context.generic -> thm -> term list
   val check_hyps: Context.generic -> thm -> thm
   val declare_term_sorts: term -> Proof.context -> Proof.context
   val extra_shyps': Proof.context -> thm -> sort list
   val check_shyps: Proof.context -> thm -> thm
   val weaken_sorts': Proof.context -> cterm -> cterm
   val elim_implies: thm -> thm -> thm
   val forall_intr_name: string * cterm -> thm -> thm
   val forall_elim_var: int -> thm -> thm
   val forall_elim_vars: int -> thm -> thm
   val instantiate_frees: ((string * sort) * ctyp) list * ((string * typ) * cterm) list -> thm -> thm
   val instantiate': ctyp option list -> cterm option list -> thm -> thm
   val forall_intr_frees: thm -> thm
   val unvarify_global: theory -> thm -> thm
   val unvarify_axiom: theory -> string -> thm
   val rename_params_rule: string list * int -> thm -> thm
   val rename_boundvars: term -> term -> thm -> thm
   val add_axiom: Proof.context -> binding * term -> theory -> (string * thm) * theory
   val add_axiom_global: binding * term -> theory -> (string * thm) * theory
   val add_def: Defs.context -> bool -> bool -> binding * term -> theory -> (string * thm) * theory
   val add_def_global: bool -> bool -> binding * term -> theory -> (string * thm) * theory
   type attribute = Context.generic * thm -> Context.generic option * thm option
   type binding = binding * attribute list
   val tag_rule: string * string -> thm -> thm
   val untag_rule: string -> thm -> thm
   val is_free_dummy: thm -> bool
   val tag_free_dummy: thm -> thm
   val def_name: string -> string
   val def_name_optional: string -> string -> string
   val def_binding: Binding.binding -> Binding.binding
   val def_binding_optional: Binding.binding -> Binding.binding -> Binding.binding
   val make_def_binding: bool -> Binding.binding -> Binding.binding
   val has_name_hint: thm -> bool
   val get_name_hint: thm -> string
   val put_name_hint: string -> thm -> thm
   val theoremK: string
   val legacy_get_kind: thm -> string
   val kind_rule: string -> thm -> thm
   val rule_attribute: thm list -> (Context.generic -> thm -> thm) -> attribute
   val declaration_attribute: (thm -> Context.generic -> Context.generic) -> attribute
   val mixed_attribute: (Context.generic * thm -> Context.generic * thm) -> attribute
   val apply_attribute: attribute -> thm -> Context.generic -> thm * Context.generic
   val attribute_declaration: attribute -> thm -> Context.generic -> Context.generic
   val theory_attributes: attribute list -> thm -> theory -> thm * theory
   val proof_attributes: attribute list -> thm -> Proof.context -> thm * Proof.context
   val no_attributes: 'a -> 'a * 'b list
   val simple_fact: 'a -> ('a * 'b list) list
   val tag: string * string -> attribute
   val untag: string -> attribute
   val kind: string -> attribute
   val reconstruct_proof_of: thm -> Proofterm.proof
   val standard_proof_of: {full: bool, expand_name: Proofterm.thm_header -> string option} ->
     thm -> Proofterm.proof
   val register_proofs: thm list lazy -> theory -> theory
   val consolidate_theory: theory -> unit
+  val expose_theory: theory -> unit
   val show_consts: bool Config.T
   val show_hyps: bool Config.T
   val show_tags: bool Config.T
   val pretty_thm_raw: Proof.context -> {quote: bool, show_hyps: bool} -> thm -> Pretty.T
   val pretty_thm: Proof.context -> thm -> Pretty.T
   val pretty_thm_item: Proof.context -> thm -> Pretty.T
   val pretty_thm_global: theory -> thm -> Pretty.T
   val string_of_thm: Proof.context -> thm -> string
   val string_of_thm_global: theory -> thm -> string
 end;
 
 structure Thm: THM =
 struct
 
 (** basic operations **)
 
 (* collecting ctyps and cterms *)
 
 val eq_ctyp = op = o apply2 Thm.typ_of;
 val op aconvc = op aconv o apply2 Thm.term_of;
 
 val add_tvars = Thm.fold_atomic_ctyps (fn a => is_TVar (Thm.typ_of a) ? insert eq_ctyp a);
 val add_frees = Thm.fold_atomic_cterms (fn a => is_Free (Thm.term_of a) ? insert (op aconvc) a);
 val add_vars = Thm.fold_atomic_cterms (fn a => is_Var (Thm.term_of a) ? insert (op aconvc) a);
 
 
 (* ctyp operations *)
 
 fun dest_funT cT =
   (case Thm.typ_of cT of
     Type ("fun", _) => let val [A, B] = Thm.dest_ctyp cT in (A, B) end
   | T => raise TYPE ("dest_funT", [T], []));
 
 (* ctyp version of strip_type: maps  [T1,...,Tn]--->T  to   ([T1,T2,...,Tn], T) *)
 fun strip_type cT =
   (case Thm.typ_of cT of
     Type ("fun", _) =>
       let
         val (cT1, cT2) = dest_funT cT;
         val (cTs, cT') = strip_type cT2
       in (cT1 :: cTs, cT') end
   | _ => ([], cT));
 
 
 (* cterm operations *)
 
 fun all_name ctxt (x, t) A =
   let
     val T = Thm.typ_of_cterm t;
     val all_const = Thm.cterm_of ctxt (Const ("Pure.all", (T --> propT) --> propT));
   in Thm.apply all_const (Thm.lambda_name (x, t) A) end;
 
 fun all ctxt t A = all_name ctxt ("", t) A;
 
 fun mk_binop c a b = Thm.apply (Thm.apply c a) b;
 fun dest_binop ct = (Thm.dest_arg1 ct, Thm.dest_arg ct);
 
 fun dest_implies ct =
   (case Thm.term_of ct of
     Const ("Pure.imp", _) $ _ $ _ => dest_binop ct
   | _ => raise TERM ("dest_implies", [Thm.term_of ct]));
 
 fun dest_equals ct =
   (case Thm.term_of ct of
     Const ("Pure.eq", _) $ _ $ _ => dest_binop ct
   | _ => raise TERM ("dest_equals", [Thm.term_of ct]));
 
 fun dest_equals_lhs ct =
   (case Thm.term_of ct of
     Const ("Pure.eq", _) $ _ $ _ => Thm.dest_arg1 ct
   | _ => raise TERM ("dest_equals_lhs", [Thm.term_of ct]));
 
 fun dest_equals_rhs ct =
   (case Thm.term_of ct of
     Const ("Pure.eq", _) $ _ $ _ => Thm.dest_arg ct
   | _ => raise TERM ("dest_equals_rhs", [Thm.term_of ct]));
 
 val lhs_of = dest_equals_lhs o Thm.cprop_of;
 val rhs_of = dest_equals_rhs o Thm.cprop_of;
 
 
 (* certified term order *)
 
 val fast_term_ord = Term_Ord.fast_term_ord o apply2 Thm.term_of;
 val term_ord = Term_Ord.term_ord o apply2 Thm.term_of;
 
 
 (* thm order: ignores theory context! *)
 
 val thm_ord =
   Term_Ord.fast_term_ord o apply2 Thm.prop_of
   <<< list_ord (prod_ord Term_Ord.fast_term_ord Term_Ord.fast_term_ord) o apply2 Thm.tpairs_of
   <<< list_ord Term_Ord.fast_term_ord o apply2 Thm.hyps_of
   <<< list_ord Term_Ord.sort_ord o apply2 Thm.shyps_of;
 
 
 (* tables and caches *)
 
 structure Ctermtab = Table(type key = cterm val ord = fast_term_ord);
 structure Thmtab = Table(type key = thm val ord = thm_ord);
 
 fun cterm_cache f = Cache.create Ctermtab.empty Ctermtab.lookup Ctermtab.update f;
 fun thm_cache f = Cache.create Thmtab.empty Thmtab.lookup Thmtab.update f;
 
 
 (* equality *)
 
 fun is_reflexive th = op aconv (Logic.dest_equals (Thm.prop_of th))
   handle TERM _ => false;
 
 val eq_thm = is_equal o thm_ord;
 
 val eq_thm_prop = op aconv o apply2 Thm.full_prop_of;
 
 fun eq_thm_strict ths =
   eq_thm ths andalso
   Context.eq_thy_id (apply2 Thm.theory_id ths) andalso
   op = (apply2 Thm.maxidx_of ths) andalso
   op = (apply2 Thm.get_tags ths);
 
 
 (* pattern equivalence *)
 
 fun equiv_thm thy ths =
   Pattern.equiv thy (apply2 (Thm.full_prop_of o Thm.transfer thy) ths);
 
 
 (* type classes and sorts *)
 
 fun class_triv thy c =
   Thm.of_class (Thm.global_ctyp_of thy (TVar ((Name.aT, 0), [c])), c);
 
 fun of_sort (T, S) = map (fn c => Thm.of_class (T, c)) S;
 
 
 (* misc operations *)
 
 fun is_dummy thm =
   (case try Logic.dest_term (Thm.concl_of thm) of
     NONE => false
   | SOME t => Term.is_dummy_pattern (Term.head_of t));
 
 
 (* collections of theorems in canonical order *)
 
 val add_thm = update eq_thm_prop;
 val del_thm = remove eq_thm_prop;
 val merge_thms = merge eq_thm_prop;
 
 val full_rules = Item_Net.init eq_thm_prop (single o Thm.full_prop_of);
 val intro_rules = Item_Net.init eq_thm_prop (single o Thm.concl_of);
 val elim_rules = Item_Net.init eq_thm_prop (single o Thm.major_prem_of);
 
 
 
 (** declared hyps and sort hyps **)
 
 structure Hyps = Proof_Data
 (
   type T = {checked_hyps: bool, hyps: Termtab.set, shyps: sort Ord_List.T};
   fun init _ : T = {checked_hyps = true, hyps = Termtab.empty, shyps = []};
 );
 
 fun map_hyps f = Hyps.map (fn {checked_hyps, hyps, shyps} =>
   let val (checked_hyps', hyps', shyps') = f (checked_hyps, hyps, shyps)
   in {checked_hyps = checked_hyps', hyps = hyps', shyps = shyps'} end);
 
 
 (* hyps *)
 
 fun declare_hyps raw_ct ctxt = ctxt |> map_hyps (fn (checked_hyps, hyps, shyps) =>
   let
     val ct = Thm.transfer_cterm (Proof_Context.theory_of ctxt) raw_ct;
     val hyps' = Termtab.update (Thm.term_of ct, ()) hyps;
   in (checked_hyps, hyps', shyps) end);
 
 fun assume_hyps ct ctxt = (Thm.assume ct, declare_hyps ct ctxt);
 
 val unchecked_hyps = map_hyps (fn (_, hyps, shyps) => (false, hyps, shyps));
 
 fun restore_hyps ctxt =
   map_hyps (fn (_, hyps, shyps) => (#checked_hyps (Hyps.get ctxt), hyps, shyps));
 
 fun undeclared_hyps context th =
   Thm.hyps_of th
   |> filter_out
     (case context of
       Context.Theory _ => K false
     | Context.Proof ctxt =>
         (case Hyps.get ctxt of
           {checked_hyps = false, ...} => K true
         | {hyps, ...} => Termtab.defined hyps));
 
 fun check_hyps context th =
   (case undeclared_hyps context th of
     [] => th
   | undeclared =>
       error (Pretty.string_of (Pretty.big_list "Undeclared hyps:"
         (map (Pretty.item o single o Syntax.pretty_term (Syntax.init_pretty context)) undeclared))));
 
 
 (* shyps *)
 
 fun declare_term_sorts t =
   map_hyps (fn (checked_hyps, hyps, shyps) =>
     (checked_hyps, hyps, Sorts.insert_term t shyps));
 
 fun extra_shyps' ctxt th =
   Sorts.subtract (#shyps (Hyps.get ctxt)) (Thm.extra_shyps th);
 
 fun check_shyps ctxt raw_th =
   let
     val th = Thm.strip_shyps raw_th;
     val extra_shyps = extra_shyps' ctxt th;
   in
     if null extra_shyps then th
     else error (Pretty.string_of (Pretty.block (Pretty.str "Pending sort hypotheses:" ::
       Pretty.brk 1 :: Pretty.commas (map (Syntax.pretty_sort ctxt) extra_shyps))))
   end;
 
 val weaken_sorts' = Thm.weaken_sorts o #shyps o Hyps.get;
 
 
 
 (** basic derived rules **)
 
 (*Elimination of implication
   A    A \<Longrightarrow> B
   ------------
         B
 *)
 fun elim_implies thA thAB = Thm.implies_elim thAB thA;
 
 
 (* forall_intr_name *)
 
 fun forall_intr_name (a, x) th =
   let
     val th' = Thm.forall_intr x th;
     val prop' = (case Thm.prop_of th' of all $ Abs (_, T, b) => all $ Abs (a, T, b));
   in Thm.renamed_prop prop' th' end;
 
 
 (* forall_elim_var(s) *)
 
 local
 
 fun dest_all ct =
   (case Thm.term_of ct of
     Const ("Pure.all", _) $ Abs (a, _, _) =>
       let val (x, ct') = Thm.dest_abs NONE (Thm.dest_arg ct)
       in SOME ((a, Thm.ctyp_of_cterm x), ct') end
   | _ => NONE);
 
 fun dest_all_list ct =
   (case dest_all ct of
     NONE => []
   | SOME (v, ct') => v :: dest_all_list ct');
 
 fun forall_elim_vars_list vars i th =
   let
     val used =
       (Thm.fold_terms o Term.fold_aterms)
         (fn Var ((x, j), _) => if i = j then insert (op =) x else I | _ => I) th [];
     val vars' = (Name.variant_list used (map #1 vars), vars)
       |> ListPair.map (fn (x, (_, T)) => Thm.var ((x, i), T));
   in fold Thm.forall_elim vars' th end;
 
 in
 
 fun forall_elim_vars i th =
   forall_elim_vars_list (dest_all_list (Thm.cprop_of th)) i th;
 
 fun forall_elim_var i th =
   let
     val vars =
       (case dest_all (Thm.cprop_of th) of
         SOME (v, _) => [v]
       | NONE => raise THM ("forall_elim_var", i, [th]));
   in forall_elim_vars_list vars i th end;
 
 end;
 
 
 (* instantiate frees *)
 
 fun instantiate_frees ([], []) th = th
   | instantiate_frees (instT, inst) th =
       let
         val idx = Thm.maxidx_of th + 1;
         fun index ((a, A), b) = (((a, idx), A), b);
         val insts = (map index instT, map index inst);
         val frees = (map (#1 o #1) instT, map (#1 o #1) inst);
 
         val hyps = Thm.chyps_of th;
         val inst_cterm =
           Thm.generalize_cterm frees idx #>
           Thm.instantiate_cterm insts;
       in
         th
         |> fold_rev Thm.implies_intr hyps
         |> Thm.generalize frees idx
         |> Thm.instantiate insts
         |> fold (elim_implies o Thm.assume o inst_cterm) hyps
       end;
 
 
 (* instantiate by left-to-right occurrence of variables *)
 
 fun instantiate' cTs cts thm =
   let
     fun err msg =
       raise TYPE ("instantiate': " ^ msg,
         map_filter (Option.map Thm.typ_of) cTs,
         map_filter (Option.map Thm.term_of) cts);
 
     fun zip_vars xs ys =
       zip_options xs ys handle ListPair.UnequalLengths =>
         err "more instantiations than variables in thm";
 
     val thm' =
       Thm.instantiate ((zip_vars (rev (Thm.fold_terms Term.add_tvars thm [])) cTs), []) thm;
     val thm'' =
       Thm.instantiate ([], zip_vars (rev (Thm.fold_terms Term.add_vars thm' [])) cts) thm';
   in thm'' end;
 
 
 (* forall_intr_frees: generalization over all suitable Free variables *)
 
 fun forall_intr_frees th =
   let
     val fixed =
       fold Term.add_frees (Thm.terms_of_tpairs (Thm.tpairs_of th) @ Thm.hyps_of th) [];
     val frees =
       Thm.fold_atomic_cterms (fn a =>
         (case Thm.term_of a of
           Free v => not (member (op =) fixed v) ? insert (op aconvc) a
         | _ => I)) th [];
   in fold Thm.forall_intr frees th end;
 
 
 (* unvarify_global: global schematic variables *)
 
 fun unvarify_global thy th =
   let
     val prop = Thm.full_prop_of th;
     val _ = map Logic.unvarify_global (prop :: Thm.hyps_of th)
       handle TERM (msg, _) => raise THM (msg, 0, [th]);
 
     val instT = rev (Term.add_tvars prop []) |> map (fn v as ((a, _), S) => (v, TFree (a, S)));
     val inst = rev (Term.add_vars prop []) |> map (fn ((a, i), T) =>
       let val T' = Term_Subst.instantiateT instT T
       in (((a, i), T'), Thm.global_cterm_of thy (Free ((a, T')))) end);
   in Thm.instantiate (map (apsnd (Thm.global_ctyp_of thy)) instT, inst) th end;
 
 fun unvarify_axiom thy = unvarify_global thy o Thm.axiom thy;
 
 
 (* user renaming of parameters in a subgoal *)
 
 (*The names, if distinct, are used for the innermost parameters of subgoal i;
   preceding parameters may be renamed to make all parameters distinct.*)
 fun rename_params_rule (names, i) st =
   let
     val (_, Bs, Bi, C) = Thm.dest_state (st, i);
     val params = map #1 (Logic.strip_params Bi);
     val short = length params - length names;
     val names' =
       if short < 0 then error "More names than parameters in subgoal!"
       else Name.variant_list names (take short params) @ names;
     val free_names = Term.fold_aterms (fn Free (x, _) => insert (op =) x | _ => I) Bi [];
     val Bi' = Logic.list_rename_params names' Bi;
   in
     (case duplicates (op =) names of
       a :: _ => (warning ("Can't rename.  Bound variables not distinct: " ^ a); st)
     | [] =>
       (case inter (op =) names free_names of
         a :: _ => (warning ("Can't rename.  Bound/Free variable clash: " ^ a); st)
       | [] => Thm.renamed_prop (Logic.list_implies (Bs @ [Bi'], C)) st))
   end;
 
 
 (* preservation of bound variable names *)
 
 fun rename_boundvars pat obj th =
   (case Term.rename_abs pat obj (Thm.prop_of th) of
     NONE => th
   | SOME prop' => Thm.renamed_prop prop' th);
 
 
 
 (** specification primitives **)
 
 (* rules *)
 
 fun stripped_sorts thy t =
   let
     val tfrees = rev (Term.add_tfrees t []);
     val tfrees' = map (fn a => (a, [])) (Name.variant_list [] (map #1 tfrees));
     val recover =
       map2 (fn (a', S') => fn (a, S) => (((a', 0), S'), Thm.global_ctyp_of thy (TVar ((a, 0), S))))
         tfrees' tfrees;
     val strip = map (apply2 TFree) (tfrees ~~ tfrees');
     val t' = Term.map_types (Term.map_atyps (perhaps (AList.lookup (op =) strip))) t;
   in (strip, recover, t') end;
 
 fun add_axiom ctxt (b, prop) thy =
   let
     val _ = Sign.no_vars ctxt prop;
     val (strip, recover, prop') = stripped_sorts thy prop;
     val constraints = map (fn (TFree (_, S), T) => (T, S)) strip;
     val of_sorts = maps (fn (T as TFree (_, S), _) => of_sort (Thm.ctyp_of ctxt T, S)) strip;
 
     val thy' = thy
       |> Theory.add_axiom ctxt (b, Logic.list_implies (maps Logic.mk_of_sort constraints, prop'));
     val axm_name = Sign.full_name thy' b;
     val axm' = Thm.axiom thy' axm_name;
     val thm =
       Thm.instantiate (recover, []) axm'
       |> unvarify_global thy'
       |> fold elim_implies of_sorts;
   in ((axm_name, thm), thy') end;
 
 fun add_axiom_global arg thy = add_axiom (Syntax.init_pretty_global thy) arg thy;
 
 fun add_def (context as (ctxt, _)) unchecked overloaded (b, prop) thy =
   let
     val _ = Sign.no_vars ctxt prop;
     val prems = map (Thm.cterm_of ctxt) (Logic.strip_imp_prems prop);
     val (_, recover, concl') = stripped_sorts thy (Logic.strip_imp_concl prop);
 
     val thy' = Theory.add_def context unchecked overloaded (b, concl') thy;
     val axm_name = Sign.full_name thy' b;
     val axm' = Thm.axiom thy' axm_name;
     val thm =
       Thm.instantiate (recover, []) axm'
       |> unvarify_global thy'
       |> fold_rev Thm.implies_intr prems;
   in ((axm_name, thm), thy') end;
 
 fun add_def_global unchecked overloaded arg thy =
   add_def (Defs.global_context thy) unchecked overloaded arg thy;
 
 
 
 (** theorem tags **)
 
 (* add / delete tags *)
 
 fun tag_rule tg = Thm.map_tags (insert (op =) tg);
 fun untag_rule s = Thm.map_tags (filter_out (fn (s', _) => s = s'));
 
 
 (* free dummy thm -- for abstract closure *)
 
 val free_dummyN = "free_dummy";
 fun is_free_dummy thm = Properties.defined (Thm.get_tags thm) free_dummyN;
 val tag_free_dummy = tag_rule (free_dummyN, "");
 
 
 (* def_name *)
 
 fun def_name c = c ^ "_def";
 
 fun def_name_optional c "" = def_name c
   | def_name_optional _ name = name;
 
 val def_binding = Binding.map_name def_name #> Binding.reset_pos;
 fun def_binding_optional b name = if Binding.is_empty name then def_binding b else name;
 fun make_def_binding cond b = if cond then def_binding b else Binding.empty;
 
 
 (* unofficial theorem names *)
 
 fun has_name_hint thm = AList.defined (op =) (Thm.get_tags thm) Markup.nameN;
 fun the_name_hint thm = the (AList.lookup (op =) (Thm.get_tags thm) Markup.nameN);
 fun get_name_hint thm = if has_name_hint thm then the_name_hint thm else "??.unknown";
 
 fun put_name_hint name = untag_rule Markup.nameN #> tag_rule (Markup.nameN, name);
 
 
 (* theorem kinds *)
 
 val theoremK = "theorem";
 
 fun legacy_get_kind thm = the_default "" (Properties.get (Thm.get_tags thm) Markup.kindN);
 
 fun kind_rule k = tag_rule (Markup.kindN, k) o untag_rule Markup.kindN;
 
 
 
 (** attributes **)
 
 (*attributes subsume any kind of rules or context modifiers*)
 type attribute = Context.generic * thm -> Context.generic option * thm option;
 
 type binding = binding * attribute list;
 
 fun rule_attribute ths f (x, th) =
   (NONE,
     (case find_first is_free_dummy (th :: ths) of
       SOME th' => SOME th'
     | NONE => SOME (f x th)));
 
 fun declaration_attribute f (x, th) =
   (if is_free_dummy th then NONE else SOME (f th x), NONE);
 
 fun mixed_attribute f (x, th) =
   let val (x', th') = f (x, th) in (SOME x', SOME th') end;
 
 fun apply_attribute (att: attribute) th x =
   let val (x', th') = att (x, check_hyps x (Thm.transfer'' x th))
   in (the_default th th', the_default x x') end;
 
 fun attribute_declaration att th x = #2 (apply_attribute att th x);
 
 fun apply_attributes mk dest =
   let
     fun app [] th x = (th, x)
       | app (att :: atts) th x = apply_attribute att th (mk x) ||> dest |-> app atts;
   in app end;
 
 val theory_attributes = apply_attributes Context.Theory Context.the_theory;
 val proof_attributes = apply_attributes Context.Proof Context.the_proof;
 
 fun no_attributes x = (x, []);
 fun simple_fact x = [(x, [])];
 
 fun tag tg = rule_attribute [] (K (tag_rule tg));
 fun untag s = rule_attribute [] (K (untag_rule s));
 fun kind k = rule_attribute [] (K (k <> "" ? kind_rule k));
 
 
 
 (** proof terms **)
 
 fun reconstruct_proof_of thm =
   Proofterm.reconstruct_proof (Thm.theory_of_thm thm) (Thm.prop_of thm) (Thm.proof_of thm);
 
 fun standard_proof_of {full, expand_name} thm =
   let val thy = Thm.theory_of_thm thm in
     reconstruct_proof_of thm
     |> Proofterm.expand_proof thy expand_name
     |> Proofterm.rew_proof thy
     |> Proofterm.no_thm_proofs
     |> not full ? Proofterm.shrink_proof
   end;
 
 
 
 (** forked proofs **)
 
 structure Proofs = Theory_Data
 (
   type T = thm list lazy list;
   val empty = [];
   fun extend _ = empty;
   fun merge _ = empty;
 );
 
 fun register_proofs ths =
   (Proofs.map o cons) (Lazy.map_finished (map Thm.trim_context) ths);
 
-fun consolidate_theory thy =
-  let
-    val thms =
-      rev (Proofs.get thy)
-      |> maps (map (Thm.transfer thy) o Lazy.force);
-    val _ = Thm.consolidate thms;
-    val _ = Thm.expose_proofs thy thms;
-  in () end;
+fun force_proofs thy = rev (Proofs.get thy) |> maps (map (Thm.transfer thy) o Lazy.force);
+
+val consolidate_theory = Thm.consolidate o force_proofs;
+
+fun expose_theory thy =
+  if Proofterm.export_enabled ()
+  then Thm.expose_proofs thy (force_proofs thy) else ();
 
 
 
 (** print theorems **)
 
 (* options *)
 
 val show_consts = Config.declare_option_bool ("show_consts", \<^here>);
 val show_hyps = Config.declare_bool ("show_hyps", \<^here>) (K false);
 val show_tags = Config.declare_bool ("show_tags", \<^here>) (K false);
 
 
 (* pretty_thm etc. *)
 
 fun pretty_tag (name, arg) = Pretty.strs [name, quote arg];
 val pretty_tags = Pretty.list "[" "]" o map pretty_tag;
 
 fun pretty_thm_raw ctxt {quote, show_hyps = show_hyps'} raw_th =
   let
     val show_tags = Config.get ctxt show_tags;
     val show_hyps = Config.get ctxt show_hyps;
 
     val th = raw_th
       |> perhaps (try (Thm.transfer' ctxt))
       |> perhaps (try Thm.strip_shyps);
 
     val hyps = if show_hyps then Thm.hyps_of th else undeclared_hyps (Context.Proof ctxt) th;
     val extra_shyps = extra_shyps' ctxt th;
     val tags = Thm.get_tags th;
     val tpairs = Thm.tpairs_of th;
 
     val q = if quote then Pretty.quote else I;
     val prt_term = q o Syntax.pretty_term ctxt;
 
 
     val hlen = length extra_shyps + length hyps + length tpairs;
     val hsymbs =
       if hlen = 0 then []
       else if show_hyps orelse show_hyps' then
         [Pretty.brk 2, Pretty.list "[" "]"
           (map (q o Syntax.pretty_flexpair ctxt) tpairs @ map prt_term hyps @
            map (Syntax.pretty_sort ctxt) extra_shyps)]
       else [Pretty.brk 2, Pretty.str ("[" ^ replicate_string hlen "." ^ "]")];
     val tsymbs =
       if null tags orelse not show_tags then []
       else [Pretty.brk 1, pretty_tags tags];
   in Pretty.block (prt_term (Thm.prop_of th) :: (hsymbs @ tsymbs)) end;
 
 fun pretty_thm ctxt = pretty_thm_raw ctxt {quote = false, show_hyps = true};
 fun pretty_thm_item ctxt th = Pretty.item [pretty_thm ctxt th];
 
 fun pretty_thm_global thy =
   pretty_thm_raw (Syntax.init_pretty_global thy) {quote = false, show_hyps = false};
 
 val string_of_thm = Pretty.string_of oo pretty_thm;
 val string_of_thm_global = Pretty.string_of oo pretty_thm_global;
 
 
 open Thm;
 
 end;
 
 structure Basic_Thm: BASIC_THM = Thm;
 open Basic_Thm;