eliminated old-style sys_error/SYS_ERROR in favour of exception Fail -- after careful checking that there is no overlap with existing handling of that;
tuned some error messages;
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 ProofContext:
22 val theory_of: Proof.context -> theory
23 val init_global: theory -> Proof.context
31 val parents_of: theory -> theory list
32 val ancestors_of: theory -> theory list
33 val theory_name: theory -> string
34 val is_stale: theory -> bool
35 val is_draft: theory -> bool
36 val reject_draft: theory -> theory
38 val display_names: theory -> string list
39 val pretty_thy: theory -> Pretty.T
40 val string_of_thy: theory -> string
41 val pretty_abbrev_thy: theory -> Pretty.T
42 val str_of_thy: theory -> string
43 val deref: theory_ref -> theory
44 val check_thy: theory -> theory_ref
45 val eq_thy: theory * theory -> bool
46 val subthy: theory * theory -> bool
47 val joinable: theory * theory -> bool
48 val merge: theory * theory -> theory
49 val merge_refs: theory_ref * theory_ref -> theory_ref
50 val copy_thy: theory -> theory
51 val checkpoint_thy: theory -> theory
52 val finish_thy: theory -> theory
53 val begin_thy: (theory -> Pretty.pp) -> string -> theory list -> theory
55 val raw_transfer: theory -> Proof.context -> Proof.context
57 datatype generic = Theory of theory | Proof of Proof.context
58 val cases: (theory -> 'a) -> (Proof.context -> 'a) -> generic -> 'a
59 val mapping: (theory -> theory) -> (Proof.context -> Proof.context) -> generic -> generic
60 val mapping_result: (theory -> 'a * theory) -> (Proof.context -> 'a * Proof.context) ->
61 generic -> 'a * generic
62 val the_theory: generic -> theory
63 val the_proof: generic -> Proof.context
64 val map_theory: (theory -> theory) -> generic -> generic
65 val map_proof: (Proof.context -> Proof.context) -> generic -> generic
66 val map_theory_result: (theory -> 'a * theory) -> generic -> 'a * generic
67 val map_proof_result: (Proof.context -> 'a * Proof.context) -> generic -> 'a * generic
68 val theory_map: (generic -> generic) -> theory -> theory
69 val proof_map: (generic -> generic) -> Proof.context -> Proof.context
70 val theory_of: generic -> theory (*total*)
71 val proof_of: generic -> Proof.context (*total*)
73 val thread_data: unit -> generic option
74 val the_thread_data: unit -> generic
75 val set_thread_data: generic option -> unit
76 val setmp_thread_data: generic option -> ('a -> 'b) -> 'a -> 'b
77 val >> : (generic -> generic) -> unit
78 val >>> : (generic -> 'a * generic) -> 'a
81 signature PRIVATE_CONTEXT =
84 structure Theory_Data:
86 val declare: Object.T -> (Object.T -> Object.T) ->
87 (Pretty.pp -> Object.T * Object.T -> Object.T) -> serial
88 val get: serial -> (Object.T -> 'a) -> theory -> 'a
89 val put: serial -> ('a -> Object.T) -> 'a -> theory -> theory
93 val declare: (theory -> Object.T) -> serial
94 val get: serial -> (Object.T -> 'a) -> Proof.context -> 'a
95 val put: serial -> ('a -> Object.T) -> 'a -> Proof.context -> Proof.context
99 structure Context: PRIVATE_CONTEXT =
102 (*** theory context ***)
106 (* data kinds and access methods *)
108 (*private copy avoids potential conflict of table exceptions*)
109 structure Datatab = Table(type key = int val ord = int_ord);
115 extend: Object.T -> Object.T,
116 merge: Pretty.pp -> Object.T * Object.T -> Object.T};
118 val kinds = Unsynchronized.ref (Datatab.empty: kind Datatab.table);
121 (case Datatab.lookup (! kinds) k of
123 | NONE => raise Fail "Invalid theory data identifier");
127 fun invoke_empty k = invoke (K o #empty) k ();
128 val invoke_extend = invoke #extend;
129 fun invoke_merge pp = invoke (fn kind => #merge kind pp);
131 fun declare_theory_data empty extend merge =
134 val kind = {empty = empty, extend = extend, merge = merge};
135 val _ = CRITICAL (fn () => Unsynchronized.change kinds (Datatab.update (k, kind)));
138 val extend_data = Datatab.map' invoke_extend;
140 fun merge_data pp (data1, data2) =
141 Datatab.keys (Datatab.merge (K true) (data1, data2))
142 |> Par_List.map (fn k =>
143 (case (Datatab.lookup data1 k, Datatab.lookup data2 k) of
144 (SOME x, NONE) => (k, invoke_extend k x)
145 | (NONE, SOME y) => (k, invoke_extend k y)
146 | (SOME x, SOME y) => (k, invoke_merge pp k (invoke_extend k x, invoke_extend k y))))
153 (** datatype theory **)
158 {self: theory Unsynchronized.ref option, (*dynamic self reference -- follows theory changes*)
159 draft: bool, (*draft mode -- linear destructive changes*)
160 id: serial, (*identifier*)
161 ids: unit Inttab.table} * (*cumulative identifiers of non-drafts -- symbolic body content*)
163 Object.T Datatab.table * (*body content*)
165 {parents: theory list, (*immediate predecessors*)
166 ancestors: theory list} * (*all predecessors -- canonical reverse order*)
168 {name: string, (*official theory name*)
169 stage: int}; (*checkpoint counter*)
171 exception THEORY of string * theory list;
173 fun rep_theory (Theory args) = args;
175 val identity_of = #1 o rep_theory;
176 val data_of = #2 o rep_theory;
177 val ancestry_of = #3 o rep_theory;
178 val history_of = #4 o rep_theory;
180 fun make_identity self draft id ids = {self = self, draft = draft, id = id, ids = ids};
181 fun make_ancestry parents ancestors = {parents = parents, ancestors = ancestors};
182 fun make_history name stage = {name = name, stage = stage};
184 val the_self = the o #self o identity_of;
185 val parents_of = #parents o ancestry_of;
186 val ancestors_of = #ancestors o ancestry_of;
187 val theory_name = #name o history_of;
192 fun eq_id (i: int, j) = i = j;
196 SOME (Unsynchronized.ref (Theory ({id = id', ...}, _, _, _))), id, ...}, _, _, _)) =
197 not (eq_id (id, id'))
198 | is_stale (Theory ({self = NONE, ...}, _, _, _)) = true;
200 fun vitalize (thy as Theory ({self = SOME r, ...}, _, _, _)) = (r := thy; thy)
201 | vitalize (thy as Theory ({self = NONE, draft, id, ids}, data, ancestry, history)) =
203 val r = Unsynchronized.ref thy;
204 val thy' = Theory (make_identity (SOME r) draft id ids, data, ancestry, history);
205 in r := thy'; thy' end;
210 val is_draft = #draft o identity_of;
212 fun reject_draft thy =
214 raise THEORY ("Illegal draft theory -- stable checkpoint required", [thy])
224 fun display_names thy =
226 val draft = if is_draft thy then [draftN] else [];
227 val {stage, ...} = history_of thy;
229 if stage = finished then theory_name thy
230 else theory_name thy ^ ":" ^ string_of_int stage;
231 val ancestor_names = map theory_name (ancestors_of thy);
232 val stale = if is_stale thy then ["!"] else [];
233 in rev (stale @ draft @ [name] @ ancestor_names) end;
235 val pretty_thy = Pretty.str_list "{" "}" o display_names;
236 val string_of_thy = Pretty.string_of o pretty_thy;
238 fun pretty_abbrev_thy thy =
240 val names = display_names thy;
241 val n = length names;
242 val abbrev = if n > 5 then "..." :: List.drop (names, n - 5) else names;
243 in Pretty.str_list "{" "}" abbrev end;
245 val str_of_thy = Pretty.str_of o pretty_abbrev_thy;
248 (* theory references *)
250 (*theory_ref provides a safe way to store dynamic references to a
251 theory in external data structures -- a plain theory value would
252 become stale as the self reference moves on*)
254 datatype theory_ref = Theory_Ref of theory Unsynchronized.ref;
256 fun deref (Theory_Ref (Unsynchronized.ref thy)) = thy;
258 fun check_thy thy = (*thread-safe version*)
259 let val thy_ref = Theory_Ref (the_self thy) in
260 if is_stale thy then error ("Stale theory encountered:\n" ^ string_of_thy thy)
267 fun insert_id draft id ids =
269 else Inttab.update (id, ()) ids;
272 (Theory ({draft = draft1, id = id1, ids = ids1, ...}, _, _, _))
273 (Theory ({draft = draft2, id = id2, ids = ids2, ...}, _, _, _)) =
274 Inttab.merge (K true) (ids1, ids2)
275 |> insert_id draft1 id1
276 |> insert_id draft2 id2;
279 (* equality and inclusion *)
281 val eq_thy = eq_id o pairself (#id o identity_of);
283 fun proper_subthy (Theory ({id, ...}, _, _, _), Theory ({ids, ...}, _, _, _)) =
284 Inttab.defined ids id;
286 fun subthy thys = eq_thy thys orelse proper_subthy thys;
288 fun joinable (thy1, thy2) = subthy (thy1, thy2) orelse subthy (thy2, thy1);
291 (* consistent ancestors *)
293 fun extend_ancestors thy thys =
294 if member eq_thy thys thy then
295 raise THEORY ("Duplicate theory node", thy :: thys)
298 fun extend_ancestors_of thy = extend_ancestors thy (ancestors_of thy);
300 val merge_ancestors = merge (fn (thy1, thy2) =>
301 eq_thy (thy1, thy2) orelse
302 theory_name thy1 = theory_name thy2 andalso
303 raise THEORY ("Inconsistent theory versions", [thy1, thy2]));
308 fun merge (thy1, thy2) =
309 if eq_thy (thy1, thy2) then thy1
310 else if proper_subthy (thy2, thy1) then thy1
311 else if proper_subthy (thy1, thy2) then thy2
312 else error (cat_lines ["Attempt to perform non-trivial merge of theories:",
313 str_of_thy thy1, str_of_thy thy2]);
315 fun merge_refs (ref1, ref2) =
316 if ref1 = ref2 then ref1
317 else check_thy (merge (deref ref1, deref ref2));
321 (** build theories **)
326 val lock = Mutex.mutex ();
328 fun SYNCHRONIZED e = Simple_Thread.synchronized "theory" lock e;
331 fun create_thy self draft ids data ancestry history =
332 let val identity = make_identity self draft (serial ()) ids;
333 in vitalize (Theory (identity, data, ancestry, history)) end;
335 fun change_thy draft' f thy =
337 val Theory ({self, draft, id, ids}, data, ancestry, history) = thy;
338 val (self', data', ancestry') =
339 if draft then (self, data, ancestry) (*destructive change!*)
340 else if #stage history > 0
341 then (NONE, data, ancestry)
342 else (NONE, extend_data data, make_ancestry [thy] (extend_ancestors_of thy));
343 val ids' = insert_id draft id ids;
344 val data'' = f data';
345 val thy' = SYNCHRONIZED (fn () =>
346 (check_thy thy; create_thy self' draft' ids' data'' ancestry' history));
349 val name_thy = change_thy false I;
350 val extend_thy = change_thy true I;
351 val modify_thy = change_thy true;
355 val Theory ({draft, id, ids, ...}, data, ancestry, history) = thy;
356 val ids' = insert_id draft id ids;
357 val thy' = SYNCHRONIZED (fn () =>
358 (check_thy thy; create_thy NONE true ids' data ancestry history));
361 val pre_pure_thy = create_thy NONE true Inttab.empty
362 Datatab.empty (make_ancestry [] []) (make_history PureN 0);
365 (* named theory nodes *)
367 fun merge_thys pp (thy1, thy2) =
369 val ids = merge_ids thy1 thy2;
370 val data = merge_data (pp thy1) (data_of thy1, data_of thy2);
371 val ancestry = make_ancestry [] [];
372 val history = make_history "" 0;
373 val thy' = SYNCHRONIZED (fn () =>
374 (check_thy thy1; check_thy thy2; create_thy NONE true ids data ancestry history));
377 fun maximal_thys thys =
378 thys |> filter_out (fn thy => exists (fn thy' => proper_subthy (thy, thy')) thys);
380 fun begin_thy pp name imports =
381 if name = "" orelse name = draftN then error ("Bad theory name: " ^ quote name)
384 val parents = maximal_thys (distinct eq_thy imports);
386 Library.foldl merge_ancestors ([], map ancestors_of parents)
387 |> fold extend_ancestors parents;
389 val Theory ({ids, ...}, data, _, _) =
391 [] => error "No parent theories"
392 | [thy] => extend_thy thy
393 | thy :: thys => Library.foldl (merge_thys pp) (thy, thys));
395 val ancestry = make_ancestry parents ancestors;
396 val history = make_history name 0;
397 val thy' = SYNCHRONIZED (fn () =>
398 (map check_thy imports; create_thy NONE true ids data ancestry history));
404 fun history_stage f thy =
406 val {name, stage} = history_of thy;
407 val _ = stage = finished andalso raise THEORY ("Theory already finished", [thy]);
408 val history' = make_history name (f stage);
409 val thy' as Theory (identity', data', ancestry', _) = name_thy thy;
410 val thy'' = SYNCHRONIZED (fn () =>
411 (check_thy thy'; vitalize (Theory (identity', data', ancestry', history'))));
414 fun checkpoint_thy thy =
415 if is_draft thy then history_stage (fn stage => stage + 1) thy
418 val finish_thy = history_stage (fn _ => finished);
423 structure Theory_Data =
426 val declare = declare_theory_data;
429 (case Datatab.lookup (data_of thy) k of
431 | NONE => invoke_empty k) |> dest;
433 fun put k mk x = modify_thy (Datatab.update (k, mk x));
439 (*** proof context ***)
441 (* datatype Proof.context *)
445 datatype context = Context of Object.T Datatab.table * theory_ref;
448 fun theory_of_proof (Proof.Context (_, thy_ref)) = deref thy_ref;
449 fun data_of_proof (Proof.Context (data, _)) = data;
450 fun map_prf f (Proof.Context (data, thy_ref)) = Proof.Context (f data, thy_ref);
453 (* proof data kinds *)
457 val kinds = Unsynchronized.ref (Datatab.empty: (theory -> Object.T) Datatab.table);
460 (case Datatab.lookup (! kinds) k of
462 | NONE => raise Fail "Invalid proof data identifier");
465 Datatab.map' (fn k => fn _ => invoke_init k thy) (! kinds);
467 fun init_new_data data thy =
468 Datatab.merge (K true) (data, init_data thy);
472 fun raw_transfer thy' (Proof.Context (data, thy_ref)) =
474 val thy = deref thy_ref;
475 val _ = subthy (thy, thy') orelse error "transfer proof context: not a super theory";
476 val _ = check_thy thy;
477 val data' = init_new_data data thy';
478 val thy_ref' = check_thy thy';
479 in Proof.Context (data', thy_ref') end;
481 structure ProofContext =
483 val theory_of = theory_of_proof;
484 fun init_global thy = Proof.Context (init_data thy, check_thy thy);
487 structure Proof_Data =
493 val _ = CRITICAL (fn () => Unsynchronized.change kinds (Datatab.update (k, init)));
497 dest (case Datatab.lookup (data_of_proof prf) k of
499 | NONE => invoke_init k (ProofContext.theory_of prf)); (*adhoc value*)
501 fun put k mk x = map_prf (Datatab.update (k, mk x));
509 (*** generic context ***)
511 datatype generic = Theory of theory | Proof of Proof.context;
513 fun cases f _ (Theory thy) = f thy
514 | cases _ g (Proof prf) = g prf;
516 fun mapping f g = cases (Theory o f) (Proof o g);
517 fun mapping_result f g = cases (apsnd Theory o f) (apsnd Proof o g);
519 val the_theory = cases I (fn _ => error "Ill-typed context: theory expected");
520 val the_proof = cases (fn _ => error "Ill-typed context: proof expected") I;
522 fun map_theory f = Theory o f o the_theory;
523 fun map_proof f = Proof o f o the_proof;
525 fun map_theory_result f = apsnd Theory o f o the_theory;
526 fun map_proof_result f = apsnd Proof o f o the_proof;
528 fun theory_map f = the_theory o f o Theory;
529 fun proof_map f = the_proof o f o Proof;
531 val theory_of = cases I ProofContext.theory_of;
532 val proof_of = cases ProofContext.init_global I;
538 local val tag = Universal.tag () : generic option Universal.tag in
541 (case Thread.getLocal tag of
542 SOME (SOME context) => SOME context
545 fun the_thread_data () =
546 (case thread_data () of
547 SOME context => context
548 | _ => error "Unknown context");
550 fun set_thread_data context = Thread.setLocal (tag, context);
551 fun setmp_thread_data context = Library.setmp_thread_data tag (thread_data ()) context;
557 val (res, context') = f (the_thread_data ());
558 val _ = set_thread_data (SOME context');
562 fun >> f = >>> (fn context => ((), f context));
564 val _ = set_thread_data (SOME (Theory pre_pure_thy));
568 structure Basic_Context: BASIC_CONTEXT = Context;
573 (*** type-safe interfaces for data declarations ***)
577 signature THEORY_DATA_PP_ARGS =
582 val merge: Pretty.pp -> T * T -> T
585 signature THEORY_DATA_ARGS =
590 val merge: T * T -> T
593 signature THEORY_DATA =
597 val put: T -> theory -> theory
598 val map: (T -> T) -> theory -> theory
601 functor Theory_Data_PP(Data: THEORY_DATA_PP_ARGS): THEORY_DATA =
607 val kind = Context.Theory_Data.declare
609 (fn Data x => Data (Data.extend x))
610 (fn pp => fn (Data x1, Data x2) => Data (Data.merge pp (x1, x2)));
612 val get = Context.Theory_Data.get kind (fn Data x => x);
613 val put = Context.Theory_Data.put kind Data;
614 fun map f thy = put (f (get thy)) thy;
618 functor Theory_Data(Data: THEORY_DATA_ARGS): THEORY_DATA =
622 val empty = Data.empty;
623 val extend = Data.extend;
624 fun merge _ = Data.merge;
631 signature PROOF_DATA_ARGS =
634 val init: theory -> T
637 signature PROOF_DATA =
640 val get: Proof.context -> T
641 val put: T -> Proof.context -> Proof.context
642 val map: (T -> T) -> Proof.context -> Proof.context
645 functor Proof_Data(Data: PROOF_DATA_ARGS): PROOF_DATA =
651 val kind = Context.Proof_Data.declare (Data o Data.init);
653 val get = Context.Proof_Data.get kind (fn Data x => x);
654 val put = Context.Proof_Data.put kind Data;
655 fun map f prf = put (f (get prf)) prf;
663 signature GENERIC_DATA_ARGS =
668 val merge: T * T -> T
671 signature GENERIC_DATA =
674 val get: Context.generic -> T
675 val put: T -> Context.generic -> Context.generic
676 val map: (T -> T) -> Context.generic -> Context.generic
679 functor Generic_Data(Data: GENERIC_DATA_ARGS): GENERIC_DATA =
682 structure Thy_Data = Theory_Data(Data);
683 structure Prf_Data = Proof_Data(type T = Data.T val init = Thy_Data.get);
687 fun get (Context.Theory thy) = Thy_Data.get thy
688 | get (Context.Proof prf) = Prf_Data.get prf;
690 fun put x (Context.Theory thy) = Context.Theory (Thy_Data.put x thy)
691 | put x (Context.Proof prf) = Context.Proof (Prf_Data.put x prf);
693 fun map f ctxt = put (f (get ctxt)) ctxt;
697 (*hide private interface*)
698 structure Context: CONTEXT = Context;