src/Pure/Isar/theory_target.ML
author haftmann
Fri Oct 19 15:08:33 2007 +0200 (2007-10-19)
changeset 25096 b8950f7cf92e
parent 25083 765528b4b419
child 25105 c9f67836c4d8
permissions -rw-r--r--
clarified abbreviations in class context
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(*  Title:      Pure/Isar/theory_target.ML
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    ID:         $Id$
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    Author:     Makarius
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Common theory/locale/class targets.
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*)
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signature THEORY_TARGET =
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sig
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  val peek: local_theory -> {target: string, is_locale: bool, is_class: bool}
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  val begin: string -> Proof.context -> local_theory
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  val init: string option -> theory -> local_theory
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  val init_cmd: xstring option -> theory -> local_theory
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end;
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structure TheoryTarget: THEORY_TARGET =
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struct
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(* context data *)
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datatype target = Target of {target: string, is_locale: bool, is_class: bool};
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fun make_target target is_locale is_class =
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  Target {target = target, is_locale = is_locale, is_class = is_class};
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structure Data = ProofDataFun
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(
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  type T = target;
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  fun init _ = make_target "" false false;
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);
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val peek = (fn Target args => args) o Data.get;
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(* pretty *)
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fun pretty (Target {target, is_locale, is_class}) ctxt =
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  let
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    val thy = ProofContext.theory_of ctxt;
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    val target_name = (if is_class then "class " else "locale ") ^ Locale.extern thy target;
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    val fixes = map (fn (x, T) => (x, SOME T, NoSyn)) (#1 (ProofContext.inferred_fixes ctxt));
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    val assumes = map (fn A => (("", []), [(A, [])])) (map Thm.term_of (Assumption.assms_of ctxt));
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    val elems =
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      (if null fixes then [] else [Element.Fixes fixes]) @
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      (if null assumes then [] else [Element.Assumes assumes]);
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  in
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    Pretty.block [Pretty.str "theory", Pretty.brk 1, Pretty.str (Context.theory_name thy)] ::
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     (if target = "" then []
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      else if null elems then [Pretty.str target_name]
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      else [Pretty.big_list (target_name ^ " =")
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        (map (Pretty.chunks o Element.pretty_ctxt ctxt) elems)])
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  end;
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(* target declarations *)
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fun target_decl add (Target {target, ...}) d lthy =
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  let
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    val d' = Morphism.transform (LocalTheory.target_morphism lthy) d;
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    val d0 = Morphism.form d';
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  in
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    if target = "" then
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      lthy
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      |> LocalTheory.theory (Context.theory_map d0)
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      |> LocalTheory.target (Context.proof_map d0)
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    else
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      lthy
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      |> LocalTheory.target (add target d')
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  end;
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val type_syntax = target_decl Locale.add_type_syntax;
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val term_syntax = target_decl Locale.add_term_syntax;
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val declaration = target_decl Locale.add_declaration;
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fun target_naming (Target {target, ...}) lthy =
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  (if target = "" then Sign.naming_of (ProofContext.theory_of lthy)
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   else ProofContext.naming_of (LocalTheory.target_of lthy))
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  |> NameSpace.qualified_names;
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(* notes *)
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fun import_export_proof ctxt (name, raw_th) =
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  let
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    val thy = ProofContext.theory_of ctxt;
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    val thy_ctxt = ProofContext.init thy;
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    val certT = Thm.ctyp_of thy;
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    val cert = Thm.cterm_of thy;
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    (*export assumes/defines*)
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    val th = Goal.norm_result raw_th;
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    val (defs, th') = LocalDefs.export ctxt thy_ctxt th;
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    val concl_conv = MetaSimplifier.rewrite true defs (Thm.cprop_of th);
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    val assms = map (MetaSimplifier.rewrite_rule defs o Thm.assume) (Assumption.assms_of ctxt);
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    val nprems = Thm.nprems_of th' - Thm.nprems_of th;
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    (*export fixes*)
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    val tfrees = map TFree (Thm.fold_terms Term.add_tfrees th' []);
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    val frees = map Free (Thm.fold_terms Term.add_frees th' []);
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    val (th'' :: vs) = (th' :: map (Drule.mk_term o cert) (map Logic.mk_type tfrees @ frees))
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      |> Variable.export ctxt thy_ctxt
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      |> Drule.zero_var_indexes_list;
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    (*thm definition*)
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    val result = th''
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      |> PureThy.name_thm true true ""
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      |> Goal.close_result
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      |> fold PureThy.tag_rule (ContextPosition.properties_of ctxt)
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      |> PureThy.name_thm true true name;
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    (*import fixes*)
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    val (tvars, vars) =
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      chop (length tfrees) (map (Thm.term_of o Drule.dest_term) vs)
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      |>> map Logic.dest_type;
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    val instT = map_filter (fn (TVar v, T) => SOME (v, T) | _ => NONE) (tvars ~~ tfrees);
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    val inst = filter (is_Var o fst) (vars ~~ frees);
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    val cinstT = map (pairself certT o apfst TVar) instT;
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    val cinst = map (pairself (cert o Term.map_types (TermSubst.instantiateT instT))) inst;
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    val result' = Thm.instantiate (cinstT, cinst) result;
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    (*import assumes/defines*)
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    val assm_tac = FIRST' (map (fn assm => Tactic.compose_tac (false, assm, 0)) assms);
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    val result'' =
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      (case SINGLE (Seq.INTERVAL assm_tac 1 nprems) result' of
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        NONE => raise THM ("Failed to re-import result", 0, [result'])
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      | SOME res => LocalDefs.trans_props ctxt [res, Thm.symmetric concl_conv])
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      |> Goal.norm_result
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      |> PureThy.name_thm false false name;
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  in (result'', result) end;
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fun notes (Target {target, is_locale, ...}) kind facts lthy =
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  let
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    val thy = ProofContext.theory_of lthy;
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    val full = LocalTheory.full_name lthy;
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    val facts' = facts
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      |> map (fn (a, bs) => (a, PureThy.burrow_fact (PureThy.name_multi (full (fst a))) bs))
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      |> PureThy.map_facts (import_export_proof lthy);
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    val local_facts = PureThy.map_facts #1 facts'
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      |> Attrib.map_facts (Attrib.attribute_i thy);
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    val target_facts = PureThy.map_facts #1 facts'
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      |> is_locale ? Element.facts_map (Element.morph_ctxt (LocalTheory.target_morphism lthy));
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    val global_facts = PureThy.map_facts #2 facts'
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      |> Attrib.map_facts (if is_locale then K I else Attrib.attribute_i thy);
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  in
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    lthy |> LocalTheory.theory
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      (Sign.qualified_names
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        #> PureThy.note_thmss_i kind global_facts #> snd
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        #> Sign.restore_naming thy)
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    |> is_locale ? LocalTheory.target (Locale.add_thmss target kind target_facts)
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    |> ProofContext.qualified_names
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    |> ProofContext.note_thmss_i kind local_facts
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    ||> ProofContext.restore_naming lthy
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  end;
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(* consts *)
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fun fork_mixfix false _ mx = ((NoSyn, NoSyn), mx)
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  | fork_mixfix true false mx = ((NoSyn, mx), NoSyn)
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  | fork_mixfix true true mx = ((mx, NoSyn), NoSyn);
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fun locale_const (prmode as (mode, _)) pos ((c, mx), rhs) phi =
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  let
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    val c' = Morphism.name phi c;
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    val rhs' = Morphism.term phi rhs;
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    val legacy_arg = (c', Term.close_schematic_term (Logic.legacy_varify rhs'));
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    val arg = (c', Term.close_schematic_term rhs');
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  in
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    Context.mapping_result
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      (Sign.add_abbrev Syntax.internalM pos legacy_arg)
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      (ProofContext.add_abbrev Syntax.internalM pos arg)
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    #-> (fn (lhs' as Const (d, _), _) =>
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        Type.similar_types (rhs, rhs') ?
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          (Context.mapping (Sign.revert_abbrev mode d) (ProofContext.revert_abbrev mode d) #>
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           Morphism.form (ProofContext.target_notation true prmode [(lhs', mx)])))
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  end;
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fun declare_consts (ta as Target {target, is_locale, is_class}) depends decls lthy =
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  let
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    val pos = ContextPosition.properties_of lthy;
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    val thy = ProofContext.theory_of lthy;
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    val xs = filter depends (#1 (ProofContext.inferred_fixes (LocalTheory.target_of lthy)));
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    fun const ((c, T), mx) thy =
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      let
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        val U = map #2 xs ---> T;
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        val (mx12, mx3) = fork_mixfix is_locale is_class mx;
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        val (const, thy') = Sign.declare_const pos (c, U, mx3) thy;
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        val t = Term.list_comb (const, map Free xs);
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      in (((c, mx12), t), thy') end;
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    fun class_const ((c, _), _) ((_, (mx1, _)), t) =
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      LocalTheory.raw_theory_result (Class.add_logical_const target pos ((c, mx1), t))
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      #> snd
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      #> LocalTheory.target (Class.refresh_syntax target);
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    val (abbrs, lthy') = lthy
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      |> LocalTheory.theory_result (fold_map const decls)
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    val abbrs' = (map o apfst o apsnd) snd abbrs;
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  in
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    lthy'
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    |> is_locale ? fold (term_syntax ta o locale_const Syntax.mode_default pos) abbrs'
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    |> is_class ? fold2 class_const decls abbrs
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    |> fold_map (apfst (apsnd snd) oo LocalDefs.add_def) abbrs'
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  end;
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(* abbrev *)
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local
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fun context_abbrev pos (c, t) lthy = lthy
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  |> ProofContext.add_abbrev Syntax.internalM pos (c, t) |> snd
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  |> LocalDefs.add_def ((c, NoSyn), t);
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fun class_abbrev target prmode pos ((c, mx), rhs) lthy = lthy
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  |> LocalTheory.raw_theory_result
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       (Class.add_syntactic_const target prmode pos ((c, mx), rhs))
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  |> snd
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  |> LocalTheory.target (Class.refresh_syntax target);
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in
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fun abbrev (ta as Target {target, is_locale, is_class}) prmode ((raw_c, mx), raw_t) lthy =
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  let
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    val pos = ContextPosition.properties_of lthy;
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    val thy_ctxt = ProofContext.init (ProofContext.theory_of lthy);
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    val target_ctxt = LocalTheory.target_of lthy;
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    val target_morphism = LocalTheory.target_morphism lthy;
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    val c = Morphism.name target_morphism raw_c;
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    val t = Morphism.term target_morphism raw_t;
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    val xs = map Free (rev (Variable.add_fixed target_ctxt t []));
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    val ((mx1, mx2), mx3) = fork_mixfix is_locale is_class mx;
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    val global_rhs =
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      singleton (Variable.export_terms (Variable.declare_term t target_ctxt) thy_ctxt)
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        (fold_rev lambda xs t);
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  in
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    if is_locale then
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      lthy
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      |> LocalTheory.theory_result (Sign.add_abbrev Syntax.internalM pos (c, global_rhs))
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      |-> (fn (lhs, _) =>
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        let val lhs' = Term.list_comb (Logic.unvarify lhs, xs) in
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          term_syntax ta (locale_const prmode pos ((c, mx2), lhs')) #>
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          is_class ? class_abbrev target prmode pos ((c, mx1), lhs')
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        end)
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      |> context_abbrev pos (c, raw_t)
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    else
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      lthy
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      |> LocalTheory.theory
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        (Sign.add_abbrev (#1 prmode) pos (c, global_rhs)
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          #-> (fn (lhs, _) => Sign.notation true prmode [(lhs, mx3)]))
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      |> context_abbrev pos (c, raw_t)
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  end;
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end;
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(* define *)
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fun define (ta as Target {target, is_locale, is_class})
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    kind ((c, mx), ((name, atts), rhs)) lthy =
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  let
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    val thy = ProofContext.theory_of lthy;
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    val thy_ctxt = ProofContext.init thy;
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    val name' = Thm.def_name_optional c name;
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    val (rhs', rhs_conv) =
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      LocalDefs.export_cterm lthy thy_ctxt (Thm.cterm_of thy rhs) |>> Thm.term_of;
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    val xs = Variable.add_fixed (LocalTheory.target_of lthy) rhs' [];
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    val T = Term.fastype_of rhs;
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    (*consts*)
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    val ([(lhs, local_def)], lthy2) = lthy
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      |> declare_consts ta (member (op =) xs) [((c, T), mx)];
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    val (_, lhs') = Logic.dest_equals (Thm.prop_of local_def);
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    (*def*)
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    val (global_def, lthy3) = lthy2
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      |> LocalTheory.theory_result (Thm.add_def false (name', Logic.mk_equals (lhs', rhs')));
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    val def = LocalDefs.trans_terms lthy3
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      [(*c == global.c xs*)     local_def,
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       (*global.c xs == rhs'*)  global_def,
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       (*rhs' == rhs*)          Thm.symmetric rhs_conv];
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    (*notes*)
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    val ([(res_name, [res])], lthy4) = lthy3
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      |> notes ta kind [((name', atts), [([def], [])])];
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  in ((lhs, (res_name, res)), lthy4) end;
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(* axioms *)
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fun axioms ta kind (vars, specs) lthy =
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  let
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    val thy_ctxt = ProofContext.init (ProofContext.theory_of lthy);
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    val expanded_props = map (Assumption.export_term lthy thy_ctxt) (maps snd specs);
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    val xs = fold Term.add_frees expanded_props [];
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    (*consts*)
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    val (consts, lthy') = declare_consts ta (member (op =) xs) vars lthy;
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    val global_consts = map (Term.dest_Const o Term.head_of o Thm.term_of o Thm.rhs_of o #2) consts;
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    (*axioms*)
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    val hyps = map Thm.term_of (Assumption.assms_of lthy');
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    fun axiom ((name, atts), props) thy = thy
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      |> fold_map (Thm.add_axiom hyps) (PureThy.name_multi name props)
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      |-> (fn ths => pair ((name, atts), [(ths, [])]));
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  in
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    lthy'
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    |> fold Variable.declare_term expanded_props
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    |> LocalTheory.theory (fold (fn c => Theory.add_deps "" c []) global_consts)
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    |> LocalTheory.theory_result (fold_map axiom specs)
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    |-> notes ta kind
wenzelm@24987
   321
    |>> pair (map #1 consts)
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   322
  end;
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   323
wenzelm@24939
   324
wenzelm@20894
   325
(* init and exit *)
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   326
wenzelm@25012
   327
fun begin target ctxt =
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  let
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    val thy = ProofContext.theory_of ctxt;
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    val is_locale = target <> "";
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    val is_class = Class.is_class thy target;
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    val ta = Target {target = target, is_locale = is_locale, is_class = is_class};
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   333
  in
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    ctxt
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    |> Data.put ta
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   336
    |> is_class ? Class.init target
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    |> LocalTheory.init (NameSpace.base target)
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     {pretty = pretty ta,
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   339
      axioms = axioms ta,
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   340
      abbrev = abbrev ta,
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   341
      define = define ta,
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   342
      notes = notes ta,
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   343
      type_syntax = type_syntax ta,
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   344
      term_syntax = term_syntax ta,
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   345
      declaration = declaration ta,
wenzelm@25012
   346
      target_naming = target_naming ta,
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   347
      reinit = fn _ =>
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        begin target o (if is_locale then Locale.init target else ProofContext.init),
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   349
      exit = LocalTheory.target_of}
wenzelm@21747
   350
  end;
wenzelm@20894
   351
wenzelm@24935
   352
fun init NONE thy = begin "" (ProofContext.init thy)
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  | init (SOME target) thy = begin target (Locale.init target thy);
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   354
wenzelm@24935
   355
fun init_cmd (SOME "-") thy = init NONE thy
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   356
  | init_cmd target thy = init (Option.map (Locale.intern thy) target) thy;
wenzelm@20894
   357
wenzelm@20894
   358
end;