1 (* Title: Pure/context.ML
2 Author: Markus Wenzel, TU Muenchen
4 Generic theory contexts with unique identity, arbitrarily typed data,
5 monotonic development graph and history support. Generic proof
6 contexts with arbitrarily typed data.
8 Firm naming conventions:
9 thy, thy', thy1, thy2: theory
10 ctxt, ctxt', ctxt1, ctxt2: Proof.context
11 context: Context.generic
14 signature BASIC_CONTEXT =
18 exception THEORY of string * theory list
19 structure Proof: sig type context end
20 structure Proof_Context:
22 val theory_of: Proof.context -> theory
23 val init_global: theory -> Proof.context
31 val timing: bool Unsynchronized.ref
33 val parents_of: theory -> theory list
34 val ancestors_of: theory -> theory list
35 val theory_name: theory -> string
36 val is_stale: theory -> bool
37 val is_draft: theory -> bool
38 val reject_draft: theory -> theory
40 val display_names: theory -> string list
41 val pretty_thy: theory -> Pretty.T
42 val string_of_thy: theory -> string
43 val pretty_abbrev_thy: theory -> Pretty.T
44 val str_of_thy: theory -> string
45 val get_theory: theory -> string -> theory
46 val this_theory: theory -> string -> theory
47 val deref: theory_ref -> theory
48 val check_thy: theory -> theory_ref
49 val eq_thy: theory * theory -> bool
50 val subthy: theory * theory -> bool
51 val joinable: theory * theory -> bool
52 val merge: theory * theory -> theory
53 val merge_refs: theory_ref * theory_ref -> theory_ref
54 val copy_thy: theory -> theory
55 val checkpoint_thy: theory -> theory
56 val finish_thy: theory -> theory
57 val begin_thy: (theory -> pretty) -> string -> theory list -> theory
59 val raw_transfer: theory -> Proof.context -> Proof.context
61 datatype generic = Theory of theory | Proof of Proof.context
62 val cases: (theory -> 'a) -> (Proof.context -> 'a) -> generic -> 'a
63 val mapping: (theory -> theory) -> (Proof.context -> Proof.context) -> generic -> generic
64 val mapping_result: (theory -> 'a * theory) -> (Proof.context -> 'a * Proof.context) ->
65 generic -> 'a * generic
66 val the_theory: generic -> theory
67 val the_proof: generic -> Proof.context
68 val map_theory: (theory -> theory) -> generic -> generic
69 val map_proof: (Proof.context -> Proof.context) -> generic -> generic
70 val map_theory_result: (theory -> 'a * theory) -> generic -> 'a * generic
71 val map_proof_result: (Proof.context -> 'a * Proof.context) -> generic -> 'a * generic
72 val theory_map: (generic -> generic) -> theory -> theory
73 val proof_map: (generic -> generic) -> Proof.context -> Proof.context
74 val theory_of: generic -> theory (*total*)
75 val proof_of: generic -> Proof.context (*total*)
76 (*pretty printing context*)
77 val pretty: Proof.context -> pretty
78 val pretty_global: theory -> pretty
79 val pretty_context: (theory -> Proof.context) -> pretty -> Proof.context
81 val thread_data: unit -> generic option
82 val the_thread_data: unit -> generic
83 val set_thread_data: generic option -> unit
84 val setmp_thread_data: generic option -> ('a -> 'b) -> 'a -> 'b
85 val >> : (generic -> generic) -> unit
86 val >>> : (generic -> 'a * generic) -> 'a
89 signature PRIVATE_CONTEXT =
92 structure Theory_Data:
94 val declare: Position.T -> Object.T -> (Object.T -> Object.T) ->
95 (pretty -> Object.T * Object.T -> Object.T) -> serial
96 val get: serial -> (Object.T -> 'a) -> theory -> 'a
97 val put: serial -> ('a -> Object.T) -> 'a -> theory -> theory
101 val declare: (theory -> Object.T) -> serial
102 val get: serial -> (Object.T -> 'a) -> Proof.context -> 'a
103 val put: serial -> ('a -> Object.T) -> 'a -> Proof.context -> Proof.context
107 structure Context: PRIVATE_CONTEXT =
110 (*** theory context ***)
114 (* data kinds and access methods *)
116 val timing = Unsynchronized.ref false;
118 (*private copy avoids potential conflict of table exceptions*)
119 structure Datatab = Table(type key = int val ord = int_ord);
121 datatype pretty = Pretty of Object.T;
128 extend: Object.T -> Object.T,
129 merge: pretty -> Object.T * Object.T -> Object.T};
131 val kinds = Synchronized.var "Theory_Data" (Datatab.empty: kind Datatab.table);
133 fun invoke name f k x =
134 (case Datatab.lookup (Synchronized.value kinds) k of
136 if ! timing andalso name <> "" then
137 Timing.cond_timeit true ("Theory_Data." ^ name ^ Position.str_of (#pos kind))
140 | NONE => raise Fail "Invalid theory data identifier");
144 fun invoke_empty k = invoke "" (K o #empty) k ();
145 val invoke_extend = invoke "extend" #extend;
146 fun invoke_merge pp = invoke "merge" (fn kind => #merge kind pp);
148 fun declare_theory_data pos empty extend merge =
151 val kind = {pos = pos, empty = empty, extend = extend, merge = merge};
152 val _ = Synchronized.change kinds (Datatab.update (k, kind));
155 val extend_data = Datatab.map invoke_extend;
156 fun merge_data pp = Datatab.join (invoke_merge pp) o pairself extend_data;
162 (** datatype theory **)
167 {self: theory Unsynchronized.ref option, (*dynamic self reference -- follows theory changes*)
168 draft: bool, (*draft mode -- linear destructive changes*)
169 id: serial, (*identifier*)
170 ids: unit Inttab.table} * (*cumulative identifiers of non-drafts -- symbolic body content*)
172 Object.T Datatab.table * (*body content*)
174 {parents: theory list, (*immediate predecessors*)
175 ancestors: theory list} * (*all predecessors -- canonical reverse order*)
177 {name: string, (*official theory name*)
178 stage: int}; (*checkpoint counter*)
180 exception THEORY of string * theory list;
182 fun rep_theory (Theory args) = args;
184 val identity_of = #1 o rep_theory;
185 val data_of = #2 o rep_theory;
186 val ancestry_of = #3 o rep_theory;
187 val history_of = #4 o rep_theory;
189 fun make_identity self draft id ids = {self = self, draft = draft, id = id, ids = ids};
190 fun make_ancestry parents ancestors = {parents = parents, ancestors = ancestors};
191 fun make_history name stage = {name = name, stage = stage};
193 val the_self = the o #self o identity_of;
194 val parents_of = #parents o ancestry_of;
195 val ancestors_of = #ancestors o ancestry_of;
196 val theory_name = #name o history_of;
201 fun eq_id (i: int, j) = i = j;
205 SOME (Unsynchronized.ref (Theory ({id = id', ...}, _, _, _))), id, ...}, _, _, _)) =
206 not (eq_id (id, id'))
207 | is_stale (Theory ({self = NONE, ...}, _, _, _)) = true;
209 fun vitalize (thy as Theory ({self = SOME r, ...}, _, _, _)) = (r := thy; thy)
210 | vitalize (thy as Theory ({self = NONE, draft, id, ids}, data, ancestry, history)) =
212 val r = Unsynchronized.ref thy;
213 val thy' = Theory (make_identity (SOME r) draft id ids, data, ancestry, history);
214 in r := thy'; thy' end;
219 val is_draft = #draft o identity_of;
221 fun reject_draft thy =
223 raise THEORY ("Illegal draft theory -- stable checkpoint required", [thy])
233 fun display_names thy =
235 val draft = if is_draft thy then [draftN] else [];
236 val {stage, ...} = history_of thy;
238 if stage = finished then theory_name thy
239 else theory_name thy ^ ":" ^ string_of_int stage;
240 val ancestor_names = map theory_name (ancestors_of thy);
241 val stale = if is_stale thy then ["!"] else [];
242 in rev (stale @ draft @ [name] @ ancestor_names) end;
244 val pretty_thy = Pretty.str_list "{" "}" o display_names;
245 val string_of_thy = Pretty.string_of o pretty_thy;
247 fun pretty_abbrev_thy thy =
249 val names = display_names thy;
250 val n = length names;
251 val abbrev = if n > 5 then "..." :: List.drop (names, n - 5) else names;
252 in Pretty.str_list "{" "}" abbrev end;
254 val str_of_thy = Pretty.str_of o pretty_abbrev_thy;
256 fun get_theory thy name =
257 if theory_name thy <> name then
258 (case find_first (fn thy' => theory_name thy' = name) (ancestors_of thy) of
260 | NONE => error ("Unknown ancestor theory " ^ quote name))
261 else if #stage (history_of thy) = finished then thy
262 else error ("Unfinished theory " ^ quote name);
264 fun this_theory thy name =
265 if theory_name thy = name then thy
266 else get_theory thy name;
269 (* theory references *)
271 (*theory_ref provides a safe way to store dynamic references to a
272 theory in external data structures -- a plain theory value would
273 become stale as the self reference moves on*)
275 datatype theory_ref = Theory_Ref of theory Unsynchronized.ref;
277 fun deref (Theory_Ref (Unsynchronized.ref thy)) = thy;
279 fun check_thy thy = (*thread-safe version*)
280 let val thy_ref = Theory_Ref (the_self thy) in
281 if is_stale thy then error ("Stale theory encountered:\n" ^ string_of_thy thy)
288 fun insert_id draft id ids =
290 else Inttab.update (id, ()) ids;
293 (Theory ({draft = draft1, id = id1, ids = ids1, ...}, _, _, _))
294 (Theory ({draft = draft2, id = id2, ids = ids2, ...}, _, _, _)) =
295 Inttab.merge (K true) (ids1, ids2)
296 |> insert_id draft1 id1
297 |> insert_id draft2 id2;
300 (* equality and inclusion *)
302 val eq_thy = eq_id o pairself (#id o identity_of);
304 fun proper_subthy (Theory ({id, ...}, _, _, _), Theory ({ids, ...}, _, _, _)) =
305 Inttab.defined ids id;
307 fun subthy thys = eq_thy thys orelse proper_subthy thys;
309 fun joinable (thy1, thy2) = subthy (thy1, thy2) orelse subthy (thy2, thy1);
312 (* consistent ancestors *)
314 fun extend_ancestors thy thys =
315 if member eq_thy thys thy then
316 raise THEORY ("Duplicate theory node", thy :: thys)
319 fun extend_ancestors_of thy = extend_ancestors thy (ancestors_of thy);
321 val merge_ancestors = merge (fn (thy1, thy2) =>
322 eq_thy (thy1, thy2) orelse
323 theory_name thy1 = theory_name thy2 andalso
324 raise THEORY ("Inconsistent theory versions", [thy1, thy2]));
329 fun merge (thy1, thy2) =
330 if eq_thy (thy1, thy2) then thy1
331 else if proper_subthy (thy2, thy1) then thy1
332 else if proper_subthy (thy1, thy2) then thy2
333 else error (cat_lines ["Attempt to perform non-trivial merge of theories:",
334 str_of_thy thy1, str_of_thy thy2]);
336 fun merge_refs (ref1, ref2) =
337 if ref1 = ref2 then ref1
338 else check_thy (merge (deref ref1, deref ref2));
342 (** build theories **)
347 val lock = Mutex.mutex ();
349 fun SYNCHRONIZED e = Simple_Thread.synchronized "theory" lock e;
352 fun create_thy self draft ids data ancestry history =
353 let val identity = make_identity self draft (serial ()) ids;
354 in vitalize (Theory (identity, data, ancestry, history)) end;
356 fun change_thy draft' f thy =
358 val Theory ({self, draft, id, ids}, data, ancestry, history) = thy;
359 val (self', data', ancestry') =
360 if draft then (self, data, ancestry) (*destructive change!*)
361 else if #stage history > 0
362 then (NONE, data, ancestry)
363 else (NONE, extend_data data, make_ancestry [thy] (extend_ancestors_of thy));
364 val ids' = insert_id draft id ids;
365 val data'' = f data';
366 val thy' = SYNCHRONIZED (fn () =>
367 (check_thy thy; create_thy self' draft' ids' data'' ancestry' history));
370 val name_thy = change_thy false I;
371 val extend_thy = change_thy true I;
372 val modify_thy = change_thy true;
376 val Theory ({draft, id, ids, ...}, data, ancestry, history) = thy;
377 val ids' = insert_id draft id ids;
378 val thy' = SYNCHRONIZED (fn () =>
379 (check_thy thy; create_thy NONE true ids' data ancestry history));
382 val pre_pure_thy = create_thy NONE true Inttab.empty
383 Datatab.empty (make_ancestry [] []) (make_history PureN 0);
386 (* named theory nodes *)
388 fun merge_thys pp (thy1, thy2) =
390 val ids = merge_ids thy1 thy2;
391 val data = merge_data (pp thy1) (data_of thy1, data_of thy2);
392 val ancestry = make_ancestry [] [];
393 val history = make_history "" 0;
394 val thy' = SYNCHRONIZED (fn () =>
395 (check_thy thy1; check_thy thy2; create_thy NONE true ids data ancestry history));
398 fun maximal_thys thys =
399 thys |> filter_out (fn thy => exists (fn thy' => proper_subthy (thy, thy')) thys);
401 fun begin_thy pp name imports =
402 if name = "" orelse name = draftN then error ("Bad theory name: " ^ quote name)
405 val parents = maximal_thys (distinct eq_thy imports);
407 Library.foldl merge_ancestors ([], map ancestors_of parents)
408 |> fold extend_ancestors parents;
410 val Theory ({ids, ...}, data, _, _) =
412 [] => error "No parent theories"
413 | [thy] => extend_thy thy
414 | thy :: thys => Library.foldl (merge_thys pp) (thy, thys));
416 val ancestry = make_ancestry parents ancestors;
417 val history = make_history name 0;
418 val thy' = SYNCHRONIZED (fn () =>
419 (map check_thy imports; create_thy NONE true ids data ancestry history));
425 fun history_stage f thy =
427 val {name, stage} = history_of thy;
428 val _ = stage = finished andalso raise THEORY ("Theory already finished", [thy]);
429 val history' = make_history name (f stage);
430 val thy' as Theory (identity', data', ancestry', _) = name_thy thy;
431 val thy'' = SYNCHRONIZED (fn () =>
432 (check_thy thy'; vitalize (Theory (identity', data', ancestry', history'))));
435 fun checkpoint_thy thy =
436 if is_draft thy then history_stage (fn stage => stage + 1) thy
439 val finish_thy = history_stage (fn _ => finished);
444 structure Theory_Data =
447 val declare = declare_theory_data;
450 (case Datatab.lookup (data_of thy) k of
452 | NONE => invoke_empty k) |> dest;
454 fun put k mk x = modify_thy (Datatab.update (k, mk x));
460 (*** proof context ***)
462 (* datatype Proof.context *)
466 datatype context = Context of Object.T Datatab.table * theory_ref;
469 fun theory_of_proof (Proof.Context (_, thy_ref)) = deref thy_ref;
470 fun data_of_proof (Proof.Context (data, _)) = data;
471 fun map_prf f (Proof.Context (data, thy_ref)) = Proof.Context (f data, thy_ref);
474 (* proof data kinds *)
478 val kinds = Synchronized.var "Proof_Data" (Datatab.empty: (theory -> Object.T) Datatab.table);
481 (case Datatab.lookup (Synchronized.value kinds) k of
483 | NONE => raise Fail "Invalid proof data identifier");
486 Datatab.map (fn k => fn _ => invoke_init k thy) (Synchronized.value kinds);
488 fun init_new_data data thy =
489 Datatab.merge (K true) (data, init_data thy);
493 fun raw_transfer thy' (Proof.Context (data, thy_ref)) =
495 val thy = deref thy_ref;
496 val _ = subthy (thy, thy') orelse error "transfer proof context: not a super theory";
497 val _ = check_thy thy;
498 val data' = init_new_data data thy';
499 val thy_ref' = check_thy thy';
500 in Proof.Context (data', thy_ref') end;
502 structure Proof_Context =
504 val theory_of = theory_of_proof;
505 fun init_global thy = Proof.Context (init_data thy, check_thy thy);
508 structure Proof_Data =
514 val _ = Synchronized.change kinds (Datatab.update (k, init));
518 dest (case Datatab.lookup (data_of_proof prf) k of
520 | NONE => invoke_init k (Proof_Context.theory_of prf)); (*adhoc value*)
522 fun put k mk x = map_prf (Datatab.update (k, mk x));
530 (*** generic context ***)
532 datatype generic = Theory of theory | Proof of Proof.context;
534 fun cases f _ (Theory thy) = f thy
535 | cases _ g (Proof prf) = g prf;
537 fun mapping f g = cases (Theory o f) (Proof o g);
538 fun mapping_result f g = cases (apsnd Theory o f) (apsnd Proof o g);
540 val the_theory = cases I (fn _ => error "Ill-typed context: theory expected");
541 val the_proof = cases (fn _ => error "Ill-typed context: proof expected") I;
543 fun map_theory f = Theory o f o the_theory;
544 fun map_proof f = Proof o f o the_proof;
546 fun map_theory_result f = apsnd Theory o f o the_theory;
547 fun map_proof_result f = apsnd Proof o f o the_proof;
549 fun theory_map f = the_theory o f o Theory;
550 fun proof_map f = the_proof o f o Proof;
552 val theory_of = cases I Proof_Context.theory_of;
553 val proof_of = cases Proof_Context.init_global I;
556 (* pretty printing context *)
558 exception PRETTY of generic;
560 val pretty = Pretty o PRETTY o Proof;
561 val pretty_global = Pretty o PRETTY o Theory;
563 fun pretty_context init (Pretty (PRETTY context)) = cases init I context;
569 local val tag = Universal.tag () : generic option Universal.tag in
572 (case Thread.getLocal tag of
573 SOME (SOME context) => SOME context
576 fun the_thread_data () =
577 (case thread_data () of
578 SOME context => context
579 | _ => error "Unknown context");
581 fun set_thread_data context = Thread.setLocal (tag, context);
582 fun setmp_thread_data context = Library.setmp_thread_data tag (thread_data ()) context;
588 val (res, context') = f (the_thread_data ());
589 val _ = set_thread_data (SOME context');
593 fun >> f = >>> (fn context => ((), f context));
595 val _ = set_thread_data (SOME (Theory pre_pure_thy));
599 structure Basic_Context: BASIC_CONTEXT = Context;
604 (*** type-safe interfaces for data declarations ***)
608 signature THEORY_DATA_PP_ARGS =
613 val merge: Context.pretty -> T * T -> T
616 signature THEORY_DATA_ARGS =
621 val merge: T * T -> T
624 signature THEORY_DATA =
628 val put: T -> theory -> theory
629 val map: (T -> T) -> theory -> theory
632 functor Theory_Data_PP(Data: THEORY_DATA_PP_ARGS): THEORY_DATA =
639 Context.Theory_Data.declare
640 (Position.thread_data ())
642 (fn Data x => Data (Data.extend x))
643 (fn pp => fn (Data x1, Data x2) => Data (Data.merge pp (x1, x2)));
645 val get = Context.Theory_Data.get kind (fn Data x => x);
646 val put = Context.Theory_Data.put kind Data;
647 fun map f thy = put (f (get thy)) thy;
651 functor Theory_Data(Data: THEORY_DATA_ARGS): THEORY_DATA =
655 val empty = Data.empty;
656 val extend = Data.extend;
657 fun merge _ = Data.merge;
664 signature PROOF_DATA_ARGS =
667 val init: theory -> T
670 signature PROOF_DATA =
673 val get: Proof.context -> T
674 val put: T -> Proof.context -> Proof.context
675 val map: (T -> T) -> Proof.context -> Proof.context
678 functor Proof_Data(Data: PROOF_DATA_ARGS): PROOF_DATA =
684 val kind = Context.Proof_Data.declare (Data o Data.init);
686 val get = Context.Proof_Data.get kind (fn Data x => x);
687 val put = Context.Proof_Data.put kind Data;
688 fun map f prf = put (f (get prf)) prf;
696 signature GENERIC_DATA_ARGS =
701 val merge: T * T -> T
704 signature GENERIC_DATA =
707 val get: Context.generic -> T
708 val put: T -> Context.generic -> Context.generic
709 val map: (T -> T) -> Context.generic -> Context.generic
712 functor Generic_Data(Data: GENERIC_DATA_ARGS): GENERIC_DATA =
715 structure Thy_Data = Theory_Data(Data);
716 structure Prf_Data = Proof_Data(type T = Data.T val init = Thy_Data.get);
720 fun get (Context.Theory thy) = Thy_Data.get thy
721 | get (Context.Proof prf) = Prf_Data.get prf;
723 fun put x (Context.Theory thy) = Context.Theory (Thy_Data.put x thy)
724 | put x (Context.Proof prf) = Context.Proof (Prf_Data.put x prf);
726 fun map f ctxt = put (f (get ctxt)) ctxt;
730 (*hide private interface*)
731 structure Context: CONTEXT = Context;