1 (* Title: Pure/variable.ML
4 Fixed type/term variables and polymorphic term abbreviations.
9 val is_body: Proof.context -> bool
10 val set_body: bool -> Proof.context -> Proof.context
11 val restore_body: Proof.context -> Proof.context -> Proof.context
12 val names_of: Proof.context -> Name.context
13 val binds_of: Proof.context -> (typ * term) Vartab.table
14 val maxidx_of: Proof.context -> int
15 val sorts_of: Proof.context -> sort list
16 val constraints_of: Proof.context -> typ Vartab.table * sort Vartab.table
17 val is_declared: Proof.context -> string -> bool
18 val check_name: binding -> string
19 val default_type: Proof.context -> string -> typ option
20 val def_type: Proof.context -> bool -> indexname -> typ option
21 val def_sort: Proof.context -> indexname -> sort option
22 val declare_names: term -> Proof.context -> Proof.context
23 val declare_constraints: term -> Proof.context -> Proof.context
24 val declare_term: term -> Proof.context -> Proof.context
25 val declare_typ: typ -> Proof.context -> Proof.context
26 val declare_prf: Proofterm.proof -> Proof.context -> Proof.context
27 val declare_thm: thm -> Proof.context -> Proof.context
28 val global_thm_context: thm -> Proof.context
29 val variant_frees: Proof.context -> term list -> (string * 'a) list -> (string * 'a) list
30 val bind_term: indexname * term option -> Proof.context -> Proof.context
31 val expand_binds: Proof.context -> term -> term
32 val lookup_const: Proof.context -> string -> string option
33 val is_const: Proof.context -> string -> bool
34 val declare_const: string * string -> Proof.context -> Proof.context
35 val next_bound: string * typ -> Proof.context -> term * Proof.context
36 val revert_bounds: Proof.context -> term -> term
37 val is_fixed: Proof.context -> string -> bool
38 val newly_fixed: Proof.context -> Proof.context -> string -> bool
39 val fixed_ord: Proof.context -> string * string -> order
40 val intern_fixed: Proof.context -> string -> string
41 val markup_fixed: Proof.context -> string -> Markup.T
42 val lookup_fixed: Proof.context -> string -> string option
43 val revert_fixed: Proof.context -> string -> string
44 val add_fixed_names: Proof.context -> term -> string list -> string list
45 val add_fixed: Proof.context -> term -> (string * typ) list -> (string * typ) list
46 val add_free_names: Proof.context -> term -> string list -> string list
47 val add_frees: Proof.context -> term -> (string * typ) list -> (string * typ) list
48 val add_fixes_binding: binding list -> Proof.context -> string list * Proof.context
49 val add_fixes: string list -> Proof.context -> string list * Proof.context
50 val add_fixes_direct: string list -> Proof.context -> Proof.context
51 val auto_fixes: term -> Proof.context -> Proof.context
52 val variant_fixes: string list -> Proof.context -> string list * Proof.context
53 val dest_fixes: Proof.context -> (string * string) list
54 val invent_types: sort list -> Proof.context -> (string * sort) list * Proof.context
55 val export_terms: Proof.context -> Proof.context -> term list -> term list
56 val exportT_terms: Proof.context -> Proof.context -> term list -> term list
57 val exportT: Proof.context -> Proof.context -> thm list -> thm list
58 val export_prf: Proof.context -> Proof.context -> Proofterm.proof -> Proofterm.proof
59 val export: Proof.context -> Proof.context -> thm list -> thm list
60 val export_morphism: Proof.context -> Proof.context -> morphism
61 val importT_inst: term list -> Proof.context -> ((indexname * sort) * typ) list * Proof.context
62 val import_inst: bool -> term list -> Proof.context ->
63 (((indexname * sort) * typ) list * ((indexname * typ) * term) list) * Proof.context
64 val importT_terms: term list -> Proof.context -> term list * Proof.context
65 val import_terms: bool -> term list -> Proof.context -> term list * Proof.context
66 val importT: thm list -> Proof.context -> ((ctyp * ctyp) list * thm list) * Proof.context
67 val import_prf: bool -> Proofterm.proof -> Proof.context -> Proofterm.proof * Proof.context
68 val import: bool -> thm list -> Proof.context ->
69 (((ctyp * ctyp) list * (cterm * cterm) list) * thm list) * Proof.context
70 val tradeT: (Proof.context -> thm list -> thm list) -> Proof.context -> thm list -> thm list
71 val trade: (Proof.context -> thm list -> thm list) -> Proof.context -> thm list -> thm list
72 val focus: term -> Proof.context -> ((string * (string * typ)) list * term) * Proof.context
73 val focus_cterm: cterm -> Proof.context -> ((string * cterm) list * cterm) * Proof.context
74 val focus_subgoal: int -> thm -> Proof.context -> ((string * cterm) list * cterm) * Proof.context
75 val warn_extra_tfrees: Proof.context -> Proof.context -> unit
76 val polymorphic_types: Proof.context -> term list -> (indexname * sort) list * term list
77 val polymorphic: Proof.context -> term list -> term list
80 structure Variable: VARIABLE =
83 (** local context data **)
85 type fixes = string Name_Space.table;
86 val empty_fixes: fixes = Name_Space.empty_table Markup.fixedN;
88 datatype data = Data of
89 {is_body: bool, (*inner body mode*)
90 names: Name.context, (*type/term variable names*)
91 consts: string Symtab.table, (*consts within the local scope*)
92 bounds: int * ((string * typ) * string) list, (*next index, internal name, type, external name*)
93 fixes: fixes, (*term fixes -- global name space, intern ~> extern*)
94 binds: (typ * term) Vartab.table, (*term bindings*)
95 type_occs: string list Symtab.table, (*type variables -- possibly within term variables*)
96 maxidx: int, (*maximum var index*)
97 sorts: sort Ord_List.T, (*declared sort occurrences*)
99 typ Vartab.table * (*type constraints*)
100 sort Vartab.table}; (*default sorts*)
103 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =
104 Data {is_body = is_body, names = names, consts = consts, bounds = bounds, fixes = fixes,
105 binds = binds, type_occs = type_occs, maxidx = maxidx, sorts = sorts, constraints = constraints};
107 structure Data = Proof_Data
111 make_data (false, Name.context, Symtab.empty, (0, []), empty_fixes, Vartab.empty,
112 Symtab.empty, ~1, [], (Vartab.empty, Vartab.empty));
117 Data {is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints} =>
119 (f (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints)));
123 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
124 (is_body, f names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints));
128 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
129 (is_body, names, f consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints));
133 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
134 (is_body, names, consts, f bounds, fixes, binds, type_occs, maxidx, sorts, constraints));
138 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
139 (is_body, names, consts, bounds, f fixes, binds, type_occs, maxidx, sorts, constraints));
143 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
144 (is_body, names, consts, bounds, fixes, f binds, type_occs, maxidx, sorts, constraints));
146 fun map_type_occs f =
148 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
149 (is_body, names, consts, bounds, fixes, binds, f type_occs, maxidx, sorts, constraints));
153 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
154 (is_body, names, consts, bounds, fixes, binds, type_occs, f maxidx, sorts, constraints));
158 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
159 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, f sorts, constraints));
161 fun map_constraints f =
163 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
164 (is_body, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, f constraints));
166 fun rep_data ctxt = Data.get ctxt |> (fn Data rep => rep);
168 val is_body = #is_body o rep_data;
171 map_data (fn (_, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints) =>
172 (b, names, consts, bounds, fixes, binds, type_occs, maxidx, sorts, constraints));
174 fun restore_body ctxt = set_body (is_body ctxt);
176 val names_of = #names o rep_data;
177 val fixes_of = #fixes o rep_data;
178 val fixes_space = #1 o fixes_of;
179 val binds_of = #binds o rep_data;
180 val type_occs_of = #type_occs o rep_data;
181 val maxidx_of = #maxidx o rep_data;
182 val sorts_of = #sorts o rep_data;
183 val constraints_of = #constraints o rep_data;
185 val is_declared = Name.is_declared o names_of;
187 val check_name = Name_Space.base_name o tap Binding.check;
193 (* default sorts and types *)
195 fun default_type ctxt x = Vartab.lookup (#1 (constraints_of ctxt)) (x, ~1);
197 fun def_type ctxt pattern xi =
198 let val {binds, constraints = (types, _), ...} = rep_data ctxt in
199 (case Vartab.lookup types xi of
202 else Vartab.lookup binds xi |> Option.map (Type.mark_polymorphic o #1)
206 val def_sort = Vartab.lookup o #2 o constraints_of;
211 fun declare_type_names t =
212 map_names (fold_types (fold_atyps Term.declare_typ_names) t) #>
213 map_maxidx (fold_types Term.maxidx_typ t);
215 fun declare_names t =
216 declare_type_names t #>
217 map_names (fold_aterms Term.declare_term_frees t) #>
218 map_maxidx (Term.maxidx_term t);
221 (* type occurrences *)
223 fun decl_type_occsT T = fold_atyps (fn TFree (a, _) => Symtab.default (a, []) | _ => I) T;
225 val decl_type_occs = fold_term_types
226 (fn Free (x, _) => fold_atyps (fn TFree (a, _) => Symtab.insert_list (op =) (a, x) | _ => I)
227 | _ => decl_type_occsT);
229 val declare_type_occsT = map_type_occs o fold_types decl_type_occsT;
230 val declare_type_occs = map_type_occs o decl_type_occs;
235 fun constrain_tvar (xi, raw_S) =
236 let val S = #2 (Term_Position.decode_positionS raw_S)
237 in if S = dummyS then Vartab.delete_safe xi else Vartab.update (xi, S) end;
239 fun declare_constraints t = map_constraints (fn (types, sorts) =>
241 val types' = fold_aterms
242 (fn Free (x, T) => Vartab.update ((x, ~1), T)
243 | Var v => Vartab.update v
245 val sorts' = (fold_types o fold_atyps)
246 (fn TFree (x, S) => constrain_tvar ((x, ~1), S)
247 | TVar v => constrain_tvar v
249 in (types', sorts') end)
250 #> declare_type_occsT t
251 #> declare_type_names t;
254 (* common declarations *)
256 fun declare_internal t =
258 declare_type_occs t #>
259 map_sorts (Sorts.insert_term t);
262 declare_internal t #>
263 declare_constraints t;
265 val declare_typ = declare_term o Logic.mk_type;
267 val declare_prf = Proofterm.fold_proof_terms declare_internal (declare_internal o Logic.mk_type);
269 val declare_thm = Thm.fold_terms declare_internal;
270 fun global_thm_context th = declare_thm th (Proof_Context.init_global (Thm.theory_of_thm th));
273 (* renaming term/type frees *)
275 fun variant_frees ctxt ts frees =
277 val names = names_of (fold declare_names ts ctxt);
278 val xs = fst (fold_map Name.variant (map #1 frees) names);
279 in xs ~~ map snd frees end;
283 (** term bindings **)
285 fun bind_term (xi, NONE) = map_binds (Vartab.delete_safe xi)
286 | bind_term ((x, i), SOME t) =
288 val u = Term.close_schematic_term t;
289 val U = Term.fastype_of u;
290 in declare_term u #> map_binds (Vartab.update ((x, i), (U, u))) end;
292 fun expand_binds ctxt =
294 val binds = binds_of ctxt;
295 val get = fn Var (xi, _) => Vartab.lookup binds xi | _ => NONE;
296 in Envir.beta_norm o Envir.expand_term get end;
302 val lookup_const = Symtab.lookup o #consts o rep_data;
303 val is_const = is_some oo lookup_const;
305 val declare_fixed = map_consts o Symtab.delete_safe;
306 val declare_const = map_consts o Symtab.update;
312 fun next_bound (a, T) ctxt =
314 val b = Name.bound (#1 (#bounds (rep_data ctxt)));
315 val ctxt' = ctxt |> map_bounds (fn (next, bounds) => (next + 1, ((b, T), a) :: bounds));
316 in (Free (b, T), ctxt') end;
318 fun revert_bounds ctxt t =
319 (case #2 (#bounds (rep_data ctxt)) of
323 val names = Term.declare_term_names t (names_of ctxt);
324 val xs = rev (#1 (fold_map Name.variant (rev (map #2 bounds)) names));
325 fun subst ((b, T), _) x' = (Free (b, T), Syntax_Trans.mark_bound_abs (x', T));
326 in Term.subst_atomic (map2 subst bounds xs) t end);
332 (* specialized name space *)
334 val is_fixed = Name_Space.defined_entry o fixes_space;
335 fun newly_fixed inner outer = is_fixed inner andf (not o is_fixed outer);
337 val fixed_ord = Name_Space.entry_ord o fixes_space;
338 val intern_fixed = Name_Space.intern o fixes_space;
340 fun lookup_fixed ctxt x =
341 let val x' = intern_fixed ctxt x
342 in if is_fixed ctxt x' then SOME x' else NONE end;
344 fun revert_fixed ctxt x =
345 (case Symtab.lookup (#2 (fixes_of ctxt)) x of
346 SOME x' => if intern_fixed ctxt x' = x then x' else x
349 fun markup_fixed ctxt x =
350 Name_Space.markup (fixes_space ctxt) x
351 |> Markup.name (revert_fixed ctxt x);
353 fun dest_fixes ctxt =
354 let val (space, tab) = fixes_of ctxt
355 in sort (Name_Space.entry_ord space o pairself #2) (map swap (Symtab.dest tab)) end;
358 (* collect variables *)
360 fun add_free_names ctxt =
361 fold_aterms (fn Free (x, _) => not (is_fixed ctxt x) ? insert (op =) x | _ => I);
364 fold_aterms (fn Free (x, T) => not (is_fixed ctxt x) ? insert (op =) (x, T) | _ => I);
366 fun add_fixed_names ctxt =
367 fold_aterms (fn Free (x, _) => is_fixed ctxt x ? insert (op =) x | _ => I);
370 fold_aterms (fn Free (x, T) => is_fixed ctxt x ? insert (op =) (x, T) | _ => I);
378 error ("Duplicate fixed variable(s): " ^ commas (map Binding.print dups));
380 fun new_fixed ((x, x'), pos) ctxt =
381 if is_some (lookup_fixed ctxt x') then err_dups [Binding.make (x, pos)]
383 let val context = Context.Proof ctxt |> Name_Space.map_naming (K Name_Space.default_naming) in
386 (Name_Space.define context true (Binding.make (x', pos), x) #> snd #>>
387 Name_Space.alias Name_Space.default_naming (Binding.make (x, pos)) x')
389 |> declare_constraints (Syntax.free x')
392 fun new_fixes names' xs xs' ps =
393 map_names (K names') #>
394 fold new_fixed ((xs ~~ xs') ~~ ps) #>
399 fun add_fixes_binding bs ctxt =
402 (case filter (Name.is_skolem o Binding.name_of) bs of
404 | bads => error ("Illegal internal Skolem constant(s): " ^ commas (map Binding.print bads)));
406 (case duplicates (op = o pairself Binding.name_of) bs of
408 | dups => err_dups dups);
410 val xs = map check_name bs;
411 val names = names_of ctxt;
413 if is_body ctxt then fold_map Name.variant xs names |>> map Name.skolem
414 else (xs, fold Name.declare xs names);
415 in ctxt |> new_fixes names' xs xs' (map Binding.pos_of bs) end;
417 fun variant_fixes raw_xs ctxt =
419 val names = names_of ctxt;
420 val xs = map (fn x => Name.clean x |> Name.is_internal x ? Name.internal) raw_xs;
421 val (xs', names') = fold_map Name.variant xs names |>> (is_body ctxt ? map Name.skolem);
422 in ctxt |> new_fixes names' xs xs' (replicate (length xs) Position.none) end;
426 val add_fixes = add_fixes_binding o map Binding.name;
428 fun add_fixes_direct xs ctxt = ctxt
430 |> (snd o add_fixes xs)
431 |> restore_body ctxt;
433 fun auto_fixes t ctxt = ctxt
434 |> not (is_body ctxt) ? add_fixes_direct (rev (add_free_names ctxt t []))
437 fun invent_types Ss ctxt =
439 val tfrees = Name.invent (names_of ctxt) Name.aT (length Ss) ~~ Ss;
440 val ctxt' = fold (declare_constraints o Logic.mk_type o TFree) tfrees ctxt;
441 in (tfrees, ctxt') end;
445 (** export -- generalize type/term variables (beware of closure sizes) **)
447 fun export_inst inner outer =
449 val declared_outer = is_declared outer;
450 val still_fixed = not o newly_fixed inner outer;
453 Symtab.fold (fn (y, _) => not (is_fixed outer y) ? cons y)
454 (#2 (fixes_of inner)) [];
456 val type_occs_inner = type_occs_of inner;
458 Symtab.fold (fn (a, xs) =>
459 if declared_outer a orelse exists still_fixed xs
460 then I else cons a) (fold decl_type_occs ts type_occs_inner) [];
461 in (gen_fixesT, gen_fixes) end;
463 fun exportT_inst inner outer = #1 (export_inst inner outer);
465 fun exportT_terms inner outer =
466 let val mk_tfrees = exportT_inst inner outer in
468 (Term_Subst.generalize (mk_tfrees ts, [])
469 (fold (Term.fold_types Term.maxidx_typ) ts ~1 + 1))
472 fun export_terms inner outer =
473 let val (mk_tfrees, tfrees) = export_inst inner outer in
475 (Term_Subst.generalize (mk_tfrees ts, tfrees)
476 (fold Term.maxidx_term ts ~1 + 1))
479 fun export_prf inner outer prf =
481 val (mk_tfrees, frees) = export_inst (declare_prf prf inner) outer;
482 val tfrees = mk_tfrees [];
483 val idx = Proofterm.maxidx_proof prf ~1 + 1;
484 val gen_term = Term_Subst.generalize_same (tfrees, frees) idx;
485 val gen_typ = Term_Subst.generalizeT_same tfrees idx;
486 in Same.commit (Proofterm.map_proof_terms_same gen_term gen_typ) prf end;
489 fun gen_export (mk_tfrees, frees) ths =
491 val tfrees = mk_tfrees (map Thm.full_prop_of ths);
492 val maxidx = fold Thm.maxidx_thm ths ~1;
493 in map (Thm.generalize (tfrees, frees) (maxidx + 1)) ths end;
495 fun exportT inner outer = gen_export (exportT_inst inner outer, []);
496 fun export inner outer = gen_export (export_inst inner outer);
498 fun export_morphism inner outer =
500 val fact = export inner outer;
501 val term = singleton (export_terms inner outer);
502 val typ = Logic.type_map term;
504 Morphism.morphism "Variable.export" {binding = [], typ = [typ], term = [term], fact = [fact]}
509 (** import -- fix schematic type/term variables **)
511 fun importT_inst ts ctxt =
513 val tvars = rev (fold Term.add_tvars ts []);
514 val (tfrees, ctxt') = invent_types (map #2 tvars) ctxt;
515 in (tvars ~~ map TFree tfrees, ctxt') end;
517 fun import_inst is_open ts ctxt =
519 val ren = Name.clean #> (if is_open then I else Name.internal);
520 val (instT, ctxt') = importT_inst ts ctxt;
521 val vars = map (apsnd (Term_Subst.instantiateT instT)) (rev (fold Term.add_vars ts []));
522 val (xs, ctxt'') = variant_fixes (map (ren o #1 o #1) vars) ctxt';
523 val inst = vars ~~ map Free (xs ~~ map #2 vars);
524 in ((instT, inst), ctxt'') end;
526 fun importT_terms ts ctxt =
527 let val (instT, ctxt') = importT_inst ts ctxt
528 in (map (Term_Subst.instantiate (instT, [])) ts, ctxt') end;
530 fun import_terms is_open ts ctxt =
531 let val (inst, ctxt') = import_inst is_open ts ctxt
532 in (map (Term_Subst.instantiate inst) ts, ctxt') end;
534 fun importT ths ctxt =
536 val thy = Proof_Context.theory_of ctxt;
537 val (instT, ctxt') = importT_inst (map Thm.full_prop_of ths) ctxt;
538 val insts' as (instT', _) = Thm.certify_inst thy (instT, []);
539 val ths' = map (Thm.instantiate insts') ths;
540 in ((instT', ths'), ctxt') end;
542 fun import_prf is_open prf ctxt =
544 val ts = rev (Proofterm.fold_proof_terms cons (cons o Logic.mk_type) prf []);
545 val (insts, ctxt') = import_inst is_open ts ctxt;
546 in (Proofterm.instantiate insts prf, ctxt') end;
548 fun import is_open ths ctxt =
550 val thy = Proof_Context.theory_of ctxt;
551 val (insts, ctxt') = import_inst is_open (map Thm.full_prop_of ths) ctxt;
552 val insts' = Thm.certify_inst thy insts;
553 val ths' = map (Thm.instantiate insts') ths;
554 in ((insts', ths'), ctxt') end;
559 fun gen_trade imp exp f ctxt ths =
560 let val ((_, ths'), ctxt') = imp ths ctxt
561 in exp ctxt' ctxt (f ctxt' ths') end;
563 val tradeT = gen_trade importT exportT;
564 val trade = gen_trade (import true) export;
567 (* focus on outermost parameters: !!x y z. B *)
569 fun focus_params t ctxt =
572 split_list (Term.variant_frees t (Term.strip_all_vars t)); (*as they are printed :-*)
573 val (xs', ctxt') = variant_fixes xs ctxt;
575 val ctxt'' = ctxt' |> fold (declare_constraints o Free) ps;
576 in ((xs, ps), ctxt'') end;
580 val ((xs, ps), ctxt') = focus_params t ctxt;
581 val t' = Term.subst_bounds (rev (map Free ps), Term.strip_all_body t);
582 in (((xs ~~ ps), t'), ctxt') end;
584 fun forall_elim_prop t prop =
585 Thm.beta_conversion false (Thm.apply (Thm.dest_arg prop) t)
586 |> Thm.cprop_of |> Thm.dest_arg;
588 fun focus_cterm goal ctxt =
590 val cert = Thm.cterm_of (Thm.theory_of_cterm goal);
591 val ((xs, ps), ctxt') = focus_params (Thm.term_of goal) ctxt;
592 val ps' = map (cert o Free) ps;
593 val goal' = fold forall_elim_prop ps' goal;
594 in ((xs ~~ ps', goal'), ctxt') end;
596 fun focus_subgoal i st =
598 val all_vars = Thm.fold_terms Term.add_vars st [];
599 val no_binds = map (fn (xi, _) => (xi, NONE)) all_vars;
601 fold bind_term no_binds #>
602 fold (declare_constraints o Var) all_vars #>
603 focus_cterm (Thm.cprem_of st i)
608 (** implicit polymorphism **)
610 (* warn_extra_tfrees *)
612 fun warn_extra_tfrees ctxt1 ctxt2 =
614 fun occs_typ a = Term.exists_subtype (fn TFree (b, _) => a = b | _ => false);
616 (case def_type ctxt1 false (x, ~1) of
617 SOME T => if occs_typ a T then I else cons (a, x)
618 | NONE => cons (a, x));
620 val occs1 = type_occs_of ctxt1;
621 val occs2 = type_occs_of ctxt2;
622 val extras = Symtab.fold (fn (a, xs) =>
623 if Symtab.defined occs1 a then I else fold (occs_free a) xs) occs2 [];
624 val tfrees = map #1 extras |> sort_distinct string_ord;
625 val frees = map #2 extras |> sort_distinct string_ord;
627 if null extras orelse not (Context_Position.is_visible ctxt2) then ()
628 else warning ("Introduced fixed type variable(s): " ^ commas tfrees ^ " in " ^
629 space_implode " or " (map quote frees))
633 (* polymorphic terms *)
635 fun polymorphic_types ctxt ts =
637 val ctxt' = fold declare_term ts ctxt;
638 val occs = type_occs_of ctxt;
639 val occs' = type_occs_of ctxt';
640 val types = Symtab.fold (fn (a, _) => if Symtab.defined occs a then I else cons a) occs' [];
641 val idx = maxidx_of ctxt' + 1;
642 val Ts' = (fold o fold_types o fold_atyps)
644 (case Term_Subst.generalizeT types idx T of TVar v => insert (op =) v | _ => I)
646 val ts' = map (Term_Subst.generalize (types, []) idx) ts;
647 in (rev Ts', ts') end;
649 fun polymorphic ctxt ts = snd (polymorphic_types ctxt ts);