1(*  Title:      Pure/Isar/toplevel.ML
2    Author:     Markus Wenzel, TU Muenchen
3
4Isabelle/Isar toplevel transactions.
5*)
6
7signature TOPLEVEL =
8sig
9  exception UNDEF
10  type state
11  val theory_toplevel: theory -> state
12  val toplevel: state
13  val is_toplevel: state -> bool
14  val is_theory: state -> bool
15  val is_proof: state -> bool
16  val is_skipped_proof: state -> bool
17  val level: state -> int
18  val previous_theory_of: state -> theory option
19  val context_of: state -> Proof.context
20  val generic_theory_of: state -> generic_theory
21  val theory_of: state -> theory
22  val proof_of: state -> Proof.state
23  val proof_position_of: state -> int
24  val is_end_theory: state -> bool
25  val end_theory: Position.T -> state -> theory
26  val presentation_context: state -> Proof.context
27  val presentation_state: Proof.context -> state
28  val pretty_context: state -> Pretty.T list
29  val pretty_state: state -> Pretty.T list
30  val string_of_state: state -> string
31  val pretty_abstract: state -> Pretty.T
32  type transition
33  val empty: transition
34  val name_of: transition -> string
35  val pos_of: transition -> Position.T
36  val type_error: transition -> string
37  val name: string -> transition -> transition
38  val position: Position.T -> transition -> transition
39  val init_theory: (unit -> theory) -> transition -> transition
40  val is_init: transition -> bool
41  val modify_init: (unit -> theory) -> transition -> transition
42  val exit: transition -> transition
43  val keep: (state -> unit) -> transition -> transition
44  val keep': (bool -> state -> unit) -> transition -> transition
45  val keep_proof: (state -> unit) -> transition -> transition
46  val ignored: Position.T -> transition
47  val is_ignored: transition -> bool
48  val malformed: Position.T -> string -> transition
49  val generic_theory: (generic_theory -> generic_theory) -> transition -> transition
50  val theory': (bool -> theory -> theory) -> transition -> transition
51  val theory: (theory -> theory) -> transition -> transition
52  val begin_local_theory: bool -> (theory -> local_theory) -> transition -> transition
53  val end_local_theory: transition -> transition
54  val open_target: (generic_theory -> local_theory) -> transition -> transition
55  val close_target: transition -> transition
56  val local_theory': (bool * Position.T) option -> (xstring * Position.T) option ->
57    (bool -> local_theory -> local_theory) -> transition -> transition
58  val local_theory: (bool * Position.T) option -> (xstring * Position.T) option ->
59    (local_theory -> local_theory) -> transition -> transition
60  val present_local_theory: (xstring * Position.T) option -> (state -> unit) ->
61    transition -> transition
62  val local_theory_to_proof': (bool * Position.T) option -> (xstring * Position.T) option ->
63    (bool -> local_theory -> Proof.state) -> transition -> transition
64  val local_theory_to_proof: (bool * Position.T) option -> (xstring * Position.T) option ->
65    (local_theory -> Proof.state) -> transition -> transition
66  val theory_to_proof: (theory -> Proof.state) -> transition -> transition
67  val end_proof: (bool -> Proof.state -> Proof.context) -> transition -> transition
68  val forget_proof: bool -> transition -> transition
69  val proofs': (bool -> Proof.state -> Proof.state Seq.result Seq.seq) -> transition -> transition
70  val proof': (bool -> Proof.state -> Proof.state) -> transition -> transition
71  val proofs: (Proof.state -> Proof.state Seq.result Seq.seq) -> transition -> transition
72  val proof: (Proof.state -> Proof.state) -> transition -> transition
73  val actual_proof: (Proof_Node.T -> Proof_Node.T) -> transition -> transition
74  val skip_proof: (unit -> unit) -> transition -> transition
75  val skip_proof_open: transition -> transition
76  val skip_proof_close: transition -> transition
77  val exec_id: Document_ID.exec -> transition -> transition
78  val setmp_thread_position: transition -> ('a -> 'b) -> 'a -> 'b
79  val add_hook: (transition -> state -> state -> unit) -> unit
80  val get_timing: transition -> Time.time
81  val put_timing: Time.time -> transition -> transition
82  val transition: bool -> transition -> state -> state * (exn * string) option
83  val command_errors: bool -> transition -> state -> Runtime.error list * state option
84  val command_exception: bool -> transition -> state -> state
85  val reset_theory: state -> state option
86  val reset_proof: state -> state option
87  type result
88  val join_results: result -> (transition * state) list
89  val element_result: Keyword.keywords -> transition Thy_Syntax.element -> state -> result * state
90end;
91
92structure Toplevel: TOPLEVEL =
93struct
94
95(** toplevel state **)
96
97exception UNDEF = Runtime.UNDEF;
98
99
100(* datatype node *)
101
102datatype node =
103  Theory of generic_theory * Proof.context option
104    (*theory with presentation context*) |
105  Proof of Proof_Node.T * ((Proof.context -> generic_theory) * generic_theory)
106    (*proof node, finish, original theory*) |
107  Skipped_Proof of int * (generic_theory * generic_theory);
108    (*proof depth, resulting theory, original theory*)
109
110val theory_node = fn Theory (gthy, _) => SOME gthy | _ => NONE;
111val proof_node = fn Proof (prf, _) => SOME prf | _ => NONE;
112val skipped_proof_node = fn Skipped_Proof _ => true | _ => false;
113
114fun cases_node f _ (Theory (gthy, _)) = f gthy
115  | cases_node _ g (Proof (prf, _)) = g (Proof_Node.current prf)
116  | cases_node f _ (Skipped_Proof (_, (gthy, _))) = f gthy;
117
118
119(* datatype state *)
120
121datatype state = State of node option * node option;  (*current, previous*)
122
123fun theory_toplevel thy = State (SOME (Theory (Context.Theory thy, NONE)), NONE);
124
125val toplevel = State (NONE, NONE);
126
127fun is_toplevel (State (NONE, _)) = true
128  | is_toplevel _ = false;
129
130fun level (State (NONE, _)) = 0
131  | level (State (SOME (Theory _), _)) = 0
132  | level (State (SOME (Proof (prf, _)), _)) = Proof.level (Proof_Node.current prf)
133  | level (State (SOME (Skipped_Proof (d, _)), _)) = d + 1;   (*different notion of proof depth!*)
134
135fun str_of_state (State (NONE, SOME (Theory (Context.Theory thy, _)))) =
136      "at top level, result theory " ^ quote (Context.theory_name thy)
137  | str_of_state (State (NONE, _)) = "at top level"
138  | str_of_state (State (SOME (Theory (Context.Theory _, _)), _)) = "in theory mode"
139  | str_of_state (State (SOME (Theory (Context.Proof _, _)), _)) = "in local theory mode"
140  | str_of_state (State (SOME (Proof _), _)) = "in proof mode"
141  | str_of_state (State (SOME (Skipped_Proof _), _)) = "in skipped proof mode";
142
143
144(* current node *)
145
146fun node_of (State (NONE, _)) = raise UNDEF
147  | node_of (State (SOME node, _)) = node;
148
149fun is_theory state = not (is_toplevel state) andalso is_some (theory_node (node_of state));
150fun is_proof state = not (is_toplevel state) andalso is_some (proof_node (node_of state));
151fun is_skipped_proof state = not (is_toplevel state) andalso skipped_proof_node (node_of state);
152
153fun node_case f g state = cases_node f g (node_of state);
154
155fun previous_theory_of (State (_, NONE)) = NONE
156  | previous_theory_of (State (_, SOME prev)) =
157      SOME (cases_node Context.theory_of Proof.theory_of prev);
158
159val context_of = node_case Context.proof_of Proof.context_of;
160val generic_theory_of = node_case I (Context.Proof o Proof.context_of);
161val theory_of = node_case Context.theory_of Proof.theory_of;
162val proof_of = node_case (fn _ => error "No proof state") I;
163
164fun proof_position_of state =
165  (case node_of state of
166    Proof (prf, _) => Proof_Node.position prf
167  | _ => ~1);
168
169fun is_end_theory (State (NONE, SOME (Theory (Context.Theory _, _)))) = true
170  | is_end_theory _ = false;
171
172fun end_theory _ (State (NONE, SOME (Theory (Context.Theory thy, _)))) = thy
173  | end_theory pos (State (NONE, _)) = error ("Bad theory" ^ Position.here pos)
174  | end_theory pos (State (SOME _, _)) = error ("Unfinished theory" ^ Position.here pos);
175
176
177(* presentation context *)
178
179structure Presentation_State = Proof_Data
180(
181  type T = state option;
182  fun init _ = NONE;
183);
184
185fun presentation_context0 state =
186  (case try node_of state of
187    SOME (Theory (_, SOME ctxt)) => ctxt
188  | SOME node => cases_node Context.proof_of Proof.context_of node
189  | NONE =>
190      (case try Theory.get_pure () of
191        SOME thy => Proof_Context.init_global thy
192      | NONE => raise UNDEF));
193
194fun presentation_context (state as State (current, _)) =
195  presentation_context0 state
196  |> Presentation_State.put (SOME (State (current, NONE)));
197
198fun presentation_state ctxt =
199  (case Presentation_State.get ctxt of
200    NONE => State (SOME (Theory (Context.Proof ctxt, SOME ctxt)), NONE)
201  | SOME state => state);
202
203
204(* print state *)
205
206fun pretty_context state =
207  (case try node_of state of
208    NONE => []
209  | SOME node =>
210      let
211        val gthy =
212          (case node of
213            Theory (gthy, _) => gthy
214          | Proof (_, (_, gthy)) => gthy
215          | Skipped_Proof (_, (_, gthy)) => gthy);
216        val lthy = Context.cases (Named_Target.theory_init) I gthy;
217      in Local_Theory.pretty lthy end);
218
219fun pretty_state state =
220  (case try node_of state of
221    NONE => []
222  | SOME (Theory _) => []
223  | SOME (Proof (prf, _)) => Proof.pretty_state (Proof_Node.current prf)
224  | SOME (Skipped_Proof (d, _)) => [Pretty.str ("skipped proof: depth " ^ string_of_int d)]);
225
226val string_of_state = pretty_state #> Pretty.chunks #> Pretty.string_of;
227
228fun pretty_abstract state = Pretty.str ("<Isar " ^ str_of_state state ^ ">");
229
230val _ = ML_system_pp (fn _ => fn _ => Pretty.to_polyml o pretty_abstract);
231
232
233
234(** toplevel transitions **)
235
236(* node transactions -- maintaining stable checkpoints *)
237
238exception FAILURE of state * exn;
239
240local
241
242fun reset_presentation (Theory (gthy, _)) = Theory (gthy, NONE)
243  | reset_presentation node = node;
244
245in
246
247fun apply_transaction f g node =
248  let
249    val cont_node = reset_presentation node;
250    val context = cases_node I (Context.Proof o Proof.context_of) cont_node;
251    fun state_error e nd = (State (SOME nd, SOME cont_node), e);
252
253    val (result, err) =
254      cont_node
255      |> Runtime.controlled_execution (SOME context) f
256      |> state_error NONE
257      handle exn => state_error (SOME exn) cont_node;
258  in
259    (case err of
260      NONE => tap g result
261    | SOME exn => raise FAILURE (result, exn))
262  end;
263
264val exit_transaction =
265  apply_transaction
266    (fn Theory (Context.Theory thy, _) => Theory (Context.Theory (Theory.end_theory thy), NONE)
267      | node => node) (K ())
268  #> (fn State (node', _) => State (NONE, node'));
269
270end;
271
272
273(* primitive transitions *)
274
275datatype trans =
276  Init of unit -> theory |               (*init theory*)
277  Exit |                                 (*formal exit of theory*)
278  Keep of bool -> state -> unit |        (*peek at state*)
279  Transaction of (bool -> node -> node) * (state -> unit);  (*node transaction and presentation*)
280
281local
282
283fun apply_tr _ (Init f) (State (NONE, _)) =
284      State (SOME (Theory (Context.Theory (Runtime.controlled_execution NONE f ()), NONE)), NONE)
285  | apply_tr _ Exit (State (SOME (state as Theory (Context.Theory _, _)), _)) =
286      exit_transaction state
287  | apply_tr int (Keep f) state =
288      Runtime.controlled_execution (try generic_theory_of state) (fn x => tap (f int) x) state
289  | apply_tr int (Transaction (f, g)) (State (SOME node, _)) =
290      apply_transaction (fn x => f int x) g node
291  | apply_tr _ _ _ = raise UNDEF;
292
293fun apply_union _ [] state = raise FAILURE (state, UNDEF)
294  | apply_union int (tr :: trs) state =
295      apply_union int trs state
296        handle Runtime.UNDEF => apply_tr int tr state
297          | FAILURE (alt_state, UNDEF) => apply_tr int tr alt_state
298          | exn as FAILURE _ => raise exn
299          | exn => raise FAILURE (state, exn);
300
301in
302
303fun apply_trans int trs state = (apply_union int trs state, NONE)
304  handle FAILURE (alt_state, exn) => (alt_state, SOME exn) | exn => (state, SOME exn);
305
306end;
307
308
309(* datatype transition *)
310
311datatype transition = Transition of
312 {name: string,              (*command name*)
313  pos: Position.T,           (*source position*)
314  timing: Time.time,         (*prescient timing information*)
315  trans: trans list};        (*primitive transitions (union)*)
316
317fun make_transition (name, pos, timing, trans) =
318  Transition {name = name, pos = pos, timing = timing, trans = trans};
319
320fun map_transition f (Transition {name, pos, timing, trans}) =
321  make_transition (f (name, pos, timing, trans));
322
323val empty = make_transition ("", Position.none, Time.zeroTime, []);
324
325
326(* diagnostics *)
327
328fun name_of (Transition {name, ...}) = name;
329fun pos_of (Transition {pos, ...}) = pos;
330
331fun command_msg msg tr =
332  msg ^ "command " ^ quote (Markup.markup Markup.keyword1 (name_of tr)) ^
333    Position.here (pos_of tr);
334
335fun at_command tr = command_msg "At " tr;
336fun type_error tr = command_msg "Bad context for " tr;
337
338
339(* modify transitions *)
340
341fun name name = map_transition (fn (_, pos, timing, trans) =>
342  (name, pos, timing, trans));
343
344fun position pos = map_transition (fn (name, _, timing, trans) =>
345  (name, pos, timing, trans));
346
347fun add_trans tr = map_transition (fn (name, pos, timing, trans) =>
348  (name, pos, timing, tr :: trans));
349
350val reset_trans = map_transition (fn (name, pos, timing, _) =>
351  (name, pos, timing, []));
352
353
354(* basic transitions *)
355
356fun init_theory f = add_trans (Init f);
357
358fun is_init (Transition {trans = [Init _], ...}) = true
359  | is_init _ = false;
360
361fun modify_init f tr = if is_init tr then init_theory f (reset_trans tr) else tr;
362
363val exit = add_trans Exit;
364val keep' = add_trans o Keep;
365
366fun present_transaction f g = add_trans (Transaction (f, g));
367fun transaction f = present_transaction f (K ());
368
369fun keep f = add_trans (Keep (fn _ => f));
370
371fun keep_proof f =
372  keep (fn st =>
373    if is_proof st then f st
374    else if is_skipped_proof st then ()
375    else warning "No proof state");
376
377fun ignored pos = empty |> name "<ignored>" |> position pos |> keep (fn _ => ());
378fun is_ignored tr = name_of tr = "<ignored>";
379
380fun malformed pos msg =
381  empty |> name "<malformed>" |> position pos |> keep (fn _ => error msg);
382
383
384(* theory transitions *)
385
386fun generic_theory f = transaction (fn _ =>
387  (fn Theory (gthy, _) => Theory (f gthy, NONE)
388    | _ => raise UNDEF));
389
390fun theory' f = transaction (fn int =>
391  (fn Theory (Context.Theory thy, _) =>
392      let val thy' = thy
393        |> Sign.new_group
394        |> f int
395        |> Sign.reset_group;
396      in Theory (Context.Theory thy', NONE) end
397    | _ => raise UNDEF));
398
399fun theory f = theory' (K f);
400
401fun begin_local_theory begin f = transaction (fn _ =>
402  (fn Theory (Context.Theory thy, _) =>
403        let
404          val lthy = f thy;
405          val gthy = if begin then Context.Proof lthy else Context.Theory (Named_Target.exit lthy);
406          val _ =
407            (case Local_Theory.pretty lthy of
408              [] => ()
409            | prts => Output.state (Pretty.string_of (Pretty.chunks prts)));
410        in Theory (gthy, SOME lthy) end
411    | _ => raise UNDEF));
412
413val end_local_theory = transaction (fn _ =>
414  (fn Theory (Context.Proof lthy, _) => Theory (Context.Theory (Named_Target.exit lthy), SOME lthy)
415    | _ => raise UNDEF));
416
417fun open_target f = transaction (fn _ =>
418  (fn Theory (gthy, _) =>
419        let val lthy = f gthy
420        in Theory (Context.Proof lthy, SOME lthy) end
421    | _ => raise UNDEF));
422
423val close_target = transaction (fn _ =>
424  (fn Theory (Context.Proof lthy, _) =>
425        (case try Local_Theory.close_target lthy of
426          SOME ctxt' =>
427            let
428              val gthy' =
429                if can Local_Theory.assert ctxt'
430                then Context.Proof ctxt'
431                else Context.Theory (Proof_Context.theory_of ctxt');
432            in Theory (gthy', SOME lthy) end
433        | NONE => raise UNDEF)
434    | _ => raise UNDEF));
435
436fun restricted_context (SOME (strict, scope)) =
437      Proof_Context.map_naming (Name_Space.restricted strict scope)
438  | restricted_context NONE = I;
439
440fun local_theory' restricted target f = present_transaction (fn int =>
441  (fn Theory (gthy, _) =>
442        let
443          val (finish, lthy) = Named_Target.switch target gthy;
444          val lthy' = lthy
445            |> restricted_context restricted
446            |> Local_Theory.new_group
447            |> f int
448            |> Local_Theory.reset_group;
449        in Theory (finish lthy', SOME lthy') end
450    | _ => raise UNDEF))
451  (K ());
452
453fun local_theory restricted target f = local_theory' restricted target (K f);
454
455fun present_local_theory target = present_transaction (fn _ =>
456  (fn Theory (gthy, _) =>
457        let val (finish, lthy) = Named_Target.switch target gthy;
458        in Theory (finish lthy, SOME lthy) end
459    | _ => raise UNDEF));
460
461
462(* proof transitions *)
463
464fun end_proof f = transaction (fn int =>
465  (fn Proof (prf, (finish, _)) =>
466        let val state = Proof_Node.current prf in
467          if can (Proof.assert_bottom true) state then
468            let
469              val ctxt' = f int state;
470              val gthy' = finish ctxt';
471            in Theory (gthy', SOME ctxt') end
472          else raise UNDEF
473        end
474    | Skipped_Proof (0, (gthy, _)) => Theory (gthy, NONE)
475    | _ => raise UNDEF));
476
477local
478
479fun begin_proof init = transaction (fn int =>
480  (fn Theory (gthy, _) =>
481    let
482      val (finish, prf) = init int gthy;
483      val document = Options.default_string "document";
484      val skip = (document = "" orelse document = "false") andalso Goal.skip_proofs_enabled ();
485      val schematic_goal = try Proof.schematic_goal prf;
486      val _ =
487        if skip andalso schematic_goal = SOME true then
488          warning "Cannot skip proof of schematic goal statement"
489        else ();
490    in
491      if skip andalso schematic_goal = SOME false then
492        Skipped_Proof (0, (finish (Proof.global_skip_proof true prf), gthy))
493      else Proof (Proof_Node.init prf, (finish, gthy))
494    end
495  | _ => raise UNDEF));
496
497in
498
499fun local_theory_to_proof' restricted target f = begin_proof
500  (fn int => fn gthy =>
501    let
502      val (finish, lthy) = Named_Target.switch target gthy;
503      val prf = lthy
504        |> restricted_context restricted
505        |> Local_Theory.new_group
506        |> f int;
507    in (finish o Local_Theory.reset_group, prf) end);
508
509fun local_theory_to_proof restricted target f =
510  local_theory_to_proof' restricted target (K f);
511
512fun theory_to_proof f = begin_proof
513  (fn _ => fn gthy =>
514    (Context.Theory o Sign.reset_group o Sign.change_check o Proof_Context.theory_of,
515      (case gthy of
516        Context.Theory thy => f (Sign.new_group thy)
517      | _ => raise UNDEF)));
518
519end;
520
521fun forget_proof strict = transaction (fn _ =>
522  (fn Proof (prf, (_, orig_gthy)) =>
523        if strict andalso not (Proof.has_bottom_goal (Proof_Node.current prf))
524        then raise UNDEF else Theory (orig_gthy, NONE)
525    | Skipped_Proof (_, (_, orig_gthy)) => Theory (orig_gthy, NONE)
526    | _ => raise UNDEF));
527
528fun proofs' f = transaction (fn int =>
529  (fn Proof (prf, x) => Proof (Proof_Node.applys (f int) prf, x)
530    | skip as Skipped_Proof _ => skip
531    | _ => raise UNDEF));
532
533fun proof' f = proofs' ((Seq.single o Seq.Result) oo f);
534val proofs = proofs' o K;
535val proof = proof' o K;
536
537
538(* skipped proofs *)
539
540fun actual_proof f = transaction (fn _ =>
541  (fn Proof (prf, x) => Proof (f prf, x)
542    | _ => raise UNDEF));
543
544fun skip_proof f = transaction (fn _ =>
545  (fn skip as Skipped_Proof _ => (f (); skip)
546    | _ => raise UNDEF));
547
548val skip_proof_open = transaction (fn _ =>
549  (fn Skipped_Proof (d, x) => Skipped_Proof (d + 1, x)
550    | _ => raise UNDEF));
551
552val skip_proof_close = transaction (fn _ =>
553  (fn Skipped_Proof (0, (gthy, _)) => Theory (gthy, NONE)
554    | Skipped_Proof (d, x) => Skipped_Proof (d - 1, x)
555    | _ => raise UNDEF));
556
557
558
559(** toplevel transactions **)
560
561(* runtime position *)
562
563fun exec_id id (tr as Transition {pos, ...}) =
564  position (Position.put_id (Document_ID.print id) pos) tr;
565
566fun setmp_thread_position (Transition {pos, ...}) f x =
567  Position.setmp_thread_data pos f x;
568
569
570(* post-transition hooks *)
571
572local
573  val hooks =
574    Synchronized.var "Toplevel.hooks" ([]: (transition -> state -> state -> unit) list);
575in
576
577fun add_hook hook = Synchronized.change hooks (cons hook);
578fun get_hooks () = Synchronized.value hooks;
579
580end;
581
582
583(* apply transitions *)
584
585fun get_timing (Transition {timing, ...}) = timing;
586fun put_timing timing = map_transition (fn (name, pos, _, trans) => (name, pos, timing, trans));
587
588local
589
590fun app int (tr as Transition {trans, ...}) =
591  setmp_thread_position tr
592    (Timing.protocol (name_of tr) (pos_of tr) (apply_trans int trans)
593      ##> Option.map (fn UNDEF => ERROR (type_error tr) | exn => exn));
594
595in
596
597fun transition int tr st =
598  let
599    val (st', opt_err) =
600      Context.setmp_generic_context (try (Context.Proof o presentation_context0) st)
601        (fn () => app int tr st) ();
602    val opt_err' = opt_err |> Option.map
603      (fn Runtime.EXCURSION_FAIL exn_info => exn_info
604        | exn => (Runtime.exn_context (try context_of st) exn, at_command tr));
605    val _ = get_hooks () |> List.app (fn f => (try (fn () => f tr st st') (); ()));
606  in (st', opt_err') end;
607
608end;
609
610
611(* managed commands *)
612
613fun command_errors int tr st =
614  (case transition int tr st of
615    (st', NONE) => ([], SOME st')
616  | (_, SOME (exn, _)) => (Runtime.exn_messages exn, NONE));
617
618fun command_exception int tr st =
619  (case transition int tr st of
620    (st', NONE) => st'
621  | (_, SOME (exn, info)) =>
622      if Exn.is_interrupt exn then Exn.reraise exn
623      else raise Runtime.EXCURSION_FAIL (exn, info));
624
625val command = command_exception false;
626
627
628(* reset state *)
629
630local
631
632fun reset_state check trans st =
633  if check st then NONE
634  else #2 (command_errors false (trans empty) st);
635
636in
637
638val reset_theory = reset_state is_theory (forget_proof false);
639
640val reset_proof =
641  reset_state is_proof
642    (transaction (fn _ =>
643      (fn Theory (gthy, _) => Skipped_Proof (0, (gthy, gthy))
644        | _ => raise UNDEF)));
645
646end;
647
648
649(* scheduled proof result *)
650
651datatype result =
652  Result of transition * state |
653  Result_List of result list |
654  Result_Future of result future;
655
656fun join_results (Result x) = [x]
657  | join_results (Result_List xs) = maps join_results xs
658  | join_results (Result_Future x) = join_results (Future.join x);
659
660local
661
662structure Result = Proof_Data
663(
664  type T = result;
665  fun init _ = Result_List [];
666);
667
668val get_result = Result.get o Proof.context_of;
669val put_result = Proof.map_context o Result.put;
670
671fun timing_estimate elem =
672  let val trs = tl (Thy_Syntax.flat_element elem)
673  in fold (fn tr => fn t => get_timing tr + t) trs Time.zeroTime end;
674
675fun future_proofs_enabled estimate st =
676  (case try proof_of st of
677    NONE => false
678  | SOME state =>
679      not (Proof.is_relevant state) andalso
680       (if can (Proof.assert_bottom true) state
681        then Future.proofs_enabled 1
682        else Future.proofs_enabled 2 orelse Future.proofs_enabled_timing estimate));
683
684fun atom_result keywords tr st =
685  let
686    val st' =
687      if Future.proofs_enabled 1 andalso Keyword.is_diag keywords (name_of tr) then
688        (Execution.fork
689          {name = "Toplevel.diag", pos = pos_of tr, pri = ~1}
690          (fn () => command tr st); st)
691      else command tr st;
692  in (Result (tr, st'), st') end;
693
694in
695
696fun element_result keywords (Thy_Syntax.Element (tr, NONE)) st = atom_result keywords tr st
697  | element_result keywords (elem as Thy_Syntax.Element (head_tr, SOME element_rest)) st =
698      let
699        val (head_result, st') = atom_result keywords head_tr st;
700        val (body_elems, end_tr) = element_rest;
701        val estimate = timing_estimate elem;
702      in
703        if not (future_proofs_enabled estimate st')
704        then
705          let
706            val proof_trs = maps Thy_Syntax.flat_element body_elems @ [end_tr];
707            val (proof_results, st'') = fold_map (atom_result keywords) proof_trs st';
708          in (Result_List (head_result :: proof_results), st'') end
709        else
710          let
711            val finish = Context.Theory o Proof_Context.theory_of;
712
713            val future_proof =
714              Proof.future_proof (fn state =>
715                Execution.fork
716                  {name = "Toplevel.future_proof", pos = pos_of head_tr, pri = ~1}
717                  (fn () =>
718                    let
719                      val State (SOME (Proof (prf, (_, orig_gthy))), prev) = st';
720                      val prf' = Proof_Node.apply (K state) prf;
721                      val (result, result_state) =
722                        State (SOME (Proof (prf', (finish, orig_gthy))), prev)
723                        |> fold_map (element_result keywords) body_elems ||> command end_tr;
724                    in (Result_List result, presentation_context0 result_state) end))
725              #> (fn (res, state') => state' |> put_result (Result_Future res));
726
727            val forked_proof =
728              proof (future_proof #>
729                (fn state => state |> Proof.local_done_proof |> put_result (get_result state))) o
730              end_proof (fn _ => future_proof #>
731                (fn state => state |> Proof.global_done_proof |> Result.put (get_result state)));
732
733            val st'' = st'
734              |> command (head_tr |> reset_trans |> forked_proof);
735            val end_result = Result (end_tr, st'');
736            val result =
737              Result_List [head_result, Result.get (presentation_context0 st''), end_result];
738          in (result, st'') end
739      end;
740
741end;
742
743end;
744