(*  Title:      Pure/pure_thy.ML

     ID:         $Id$

     Author:     Markus Wenzel, TU Muenchen

 Theorem storage.  The ProtoPure theory.

 *)

 signature BASIC_PURE_THY =

 sig

   val get_thm: theory -> Facts.ref -> thm

   val get_thms: theory -> Facts.ref -> thm list

   structure ProtoPure:

     sig

       val thy: theory

       val prop_def: thm

       val term_def: thm

       val conjunction_def: thm

     end

 end;

 signature PURE_THY =

 sig

   include BASIC_PURE_THY

   val tag_rule: Markup.property -> thm -> thm

   val untag_rule: string -> thm -> thm

   val tag: Markup.property -> attribute

   val untag: string -> attribute

   val has_name_hint: thm -> bool

   val get_name_hint: thm -> string

   val put_name_hint: string -> thm -> thm

   val get_group: thm -> string option

   val put_group: string -> thm -> thm

   val group: string -> attribute

   val has_kind: thm -> bool

   val get_kind: thm -> string

   val kind_rule: string -> thm -> thm

   val kind: string -> attribute

   val kind_internal: attribute

   val has_internal: Markup.property list -> bool

   val is_internal: thm -> bool

   val get_thms_silent: theory -> Facts.ref -> thm list

   val theorems_of: theory -> thm list NameSpace.table

   val all_facts_of: theory -> Facts.T

   val thms_of: theory -> (string * thm) list

   val all_thms_of: theory -> (string * thm) list

   val hide_thms: bool -> string list -> theory -> theory

   val map_facts: ('a -> 'b) -> ('c * ('a list * 'd) list) list -> ('c * ('b list * 'd) list) list

   val burrow_fact: ('a list -> 'b list) -> ('a list * 'c) list -> ('b list * 'c) list

   val burrow_facts: ('a list -> 'b list) ->

     ('c * ('a list * 'd) list) list -> ('c * ('b list * 'd) list) list

   val name_multi: string -> 'a list -> (string * 'a) list

   val name_thm: bool -> bool -> string -> thm -> thm

   val name_thms: bool -> bool -> string -> thm list -> thm list

   val name_thmss: bool -> string -> (thm list * 'a) list -> (thm list * 'a) list

   val store_thm: (bstring * thm) * attribute list -> theory -> thm * theory

   val smart_store_thms: (bstring * thm list) -> thm list

   val smart_store_thms_open: (bstring * thm list) -> thm list

   val forall_elim_var: int -> thm -> thm

   val forall_elim_vars: int -> thm -> thm

   val add_thms: ((bstring * thm) * attribute list) list -> theory -> thm list * theory

   val add_thmss: ((bstring * thm list) * attribute list) list -> theory -> thm list list * theory

   val note: string -> string * thm -> theory -> thm * theory

   val note_thmss: string -> ((bstring * attribute list) *

     (Facts.ref * attribute list) list) list -> theory -> (bstring * thm list) list * theory

   val note_thmss_i: string -> ((bstring * attribute list) *

     (thm list * attribute list) list) list -> theory -> (bstring * thm list) list * theory

   val note_thmss_grouped: string -> string -> ((bstring * attribute list) *

     (thm list * attribute list) list) list -> theory -> (bstring * thm list) list * theory

   val note_thmss_qualified: string -> string -> ((bstring * attribute list) *

     (thm list * attribute list) list) list -> theory -> (bstring * thm list) list * theory

   val add_axioms: ((bstring * string) * attribute list) list -> theory -> thm list * theory

   val add_axioms_i: ((bstring * term) * attribute list) list -> theory -> thm list * theory

   val add_axiomss: ((bstring * string list) * attribute list) list ->

     theory -> thm list list * theory

   val add_axiomss_i: ((bstring * term list) * attribute list) list ->

     theory -> thm list list * theory

   val add_defs: bool -> ((bstring * string) * attribute list) list ->

     theory -> thm list * theory

   val add_defs_i: bool -> ((bstring * term) * attribute list) list ->

     theory -> thm list * theory

   val add_defs_unchecked: bool -> ((bstring * string) * attribute list) list ->

     theory -> thm list * theory

   val add_defs_unchecked_i: bool -> ((bstring * term) * attribute list) list ->

     theory -> thm list * theory

   val appl_syntax: (string * typ * mixfix) list

   val applC_syntax: (string * typ * mixfix) list

 end;

 structure PureThy: PURE_THY =

 struct

 (*** theorem tags ***)

 (* add / delete tags *)

 fun tag_rule tg = Thm.map_tags (insert (op =) tg);

 fun untag_rule s = Thm.map_tags (filter_out (fn (s', _) => s = s'));

 fun tag tg x = Thm.rule_attribute (K (tag_rule tg)) x;

 fun untag s x = Thm.rule_attribute (K (untag_rule s)) x;

 (* unofficial theorem names *)

 fun the_name_hint thm = the (AList.lookup (op =) (Thm.get_tags thm) Markup.nameN);

 val has_name_hint = can the_name_hint;

 val get_name_hint = the_default "??.unknown" o try the_name_hint;

 fun put_name_hint name = untag_rule Markup.nameN #> tag_rule (Markup.nameN, name);

 (* theorem groups *)

 fun get_group thm = AList.lookup (op =) (Thm.get_tags thm) Markup.groupN;

 fun put_group name =

   if name = "" then I else Thm.map_tags (AList.update (op =) (Markup.groupN, name));

 fun group name = Thm.rule_attribute (K (put_group name));

 (* theorem kinds *)

 fun the_kind thm = the (AList.lookup (op =) (Thm.get_tags thm) Markup.kindN);

 val has_kind = can the_kind;

 val get_kind = the_default "" o try the_kind;

 fun kind_rule k = tag_rule (Markup.kindN, k) o untag_rule Markup.kindN;

 fun kind k x = if k = "" then x else Thm.rule_attribute (K (kind_rule k)) x;

 fun kind_internal x = kind Thm.internalK x;

 fun has_internal tags = exists (fn tg => tg = (Markup.kindN, Thm.internalK)) tags;

 val is_internal = has_internal o Thm.get_tags;

 (*** theorem database ***)

 (** dataype theorems **)

 datatype thms = Thms of

  {theorems: thm list NameSpace.table,   (* FIXME legacy *)

   all_facts: Facts.T};

 fun make_thms theorems all_facts = Thms {theorems = theorems, all_facts = all_facts};

 structure TheoremsData = TheoryDataFun

 (

   type T = thms ref;   (* FIXME legacy *)

   val empty = ref (make_thms NameSpace.empty_table Facts.empty);

   fun copy (ref x) = ref x;

   fun extend (ref (Thms {theorems = _, all_facts})) = ref (make_thms NameSpace.empty_table all_facts);

   fun merge _

      (ref (Thms {theorems = _, all_facts = all_facts1}),

       ref (Thms {theorems = _, all_facts = all_facts2})) =

     ref (make_thms NameSpace.empty_table (Facts.merge (all_facts1, all_facts2)));

 );

 val get_theorems_ref = TheoremsData.get;

 val get_theorems = (fn Thms args => args) o ! o get_theorems_ref;

 val theorems_of = #theorems o get_theorems;

 val all_facts_of = #all_facts o get_theorems;

 (** retrieve theorems **)

 fun the_thms _ (SOME thms) = thms

   | the_thms name NONE = error ("Unknown theorem(s) " ^ quote name);

 local

 fun lookup_thms thy xname =

   let

     val (space, thms) = #theorems (get_theorems thy);

     val name = NameSpace.intern space xname;

   in Option.map (pair name) (Symtab.lookup thms name) end;

 fun lookup_fact thy xname =

   let

     val facts = all_facts_of thy;

     val name = NameSpace.intern (Facts.space_of facts) xname;

   in Option.map (pair name) (Facts.lookup facts name) end;

 fun show_result NONE = "none"

   | show_result (SOME (name, _)) = quote name;

 fun get_fact silent theory thmref =

   let

     val name = Facts.name_of_ref thmref;

     val new_res = lookup_fact theory name;

     val old_res = get_first (fn thy => lookup_thms thy name) (theory :: Theory.ancestors_of theory);

     val is_same =

       (case (new_res, old_res) of

         (NONE, NONE) => true

       | (SOME (name1, ths1), SOME (name2, ths2)) => name1 = name2 andalso Thm.eq_thms (ths1, ths2)

       | _ => false);

     val _ =

       if is_same orelse silent then ()

       else legacy_feature ("Fact lookup differs from old-style thm database:\n" ^

         show_result new_res ^ " vs " ^ show_result old_res ^

         Position.str_of (Position.thread_data ()));

   in Option.map #2 old_res |> the_thms name |> Facts.select thmref |> map (Thm.transfer theory) end;

 in

 val get_thms_silent = get_fact true;

 val get_thms = get_fact false;

 fun get_thm thy thmref = Facts.the_single (Facts.name_of_ref thmref) (get_thms thy thmref);

 end;

 (* thms_of etc. *)

 fun thms_of thy =

   let val thms = #2 (theorems_of thy)

   in map (`(get_name_hint)) (maps snd (Symtab.dest thms)) end;

 fun all_thms_of thy = maps thms_of (thy :: Theory.ancestors_of thy);

 (** store theorems **)                    (*DESTRUCTIVE*)

 (* hiding -- affects current theory node only *)

 fun hide_thms fully names thy = CRITICAL (fn () =>

   let

     val r as ref (Thms {theorems = (space, thms), all_facts}) = get_theorems_ref thy;

     val space' = fold (NameSpace.hide fully) names space;

   in r := make_thms (space', thms) all_facts; thy end);

 (* fact specifications *)

 fun map_facts f = map (apsnd (map (apfst (map f))));

 fun burrow_fact f = split_list #>> burrow f #> op ~~;

 fun burrow_facts f = split_list ##> burrow (burrow_fact f) #> op ~~;

 (* naming *)

 fun gen_names _ len "" = replicate len ""

   | gen_names j len name = map (fn i => name ^ "_" ^ string_of_int i) (j + 1 upto j + len);

 fun name_multi name [x] = [(name, x)]

   | name_multi name xs = gen_names 0 (length xs) name ~~ xs;

 fun name_thm pre official name thm = thm

   |> (if Thm.get_name thm <> "" andalso pre orelse not official then I else Thm.put_name name)

   |> (if has_name_hint thm andalso pre orelse name = "" then I else put_name_hint name)

   |> Thm.map_tags (Position.default_properties (Position.thread_data ()));

 fun name_thms pre official name xs =

   map (uncurry (name_thm pre official)) (name_multi name xs);

 fun name_thmss official name fact =

   burrow_fact (name_thms true official name) fact;

 (* enter_thms *)

 fun warn_overwrite name = warning ("Replaced old copy of theorems " ^ quote name);

 fun warn_same name = warning ("Theorem database already contains a copy of " ^ quote name);

 fun enter_thms _ _ app_att ("", thms) thy = app_att (thy, thms) |> swap

   | enter_thms pre_name post_name app_att (bname, thms) thy = CRITICAL (fn () =>

       let

         val name = Sign.full_name thy bname;

         val (thy', thms') = apsnd (post_name name) (app_att (thy, pre_name name thms));

         val r as ref (Thms {theorems = (space, theorems), all_facts}) = get_theorems_ref thy';

         val space' = Sign.declare_name thy' name space;

         val theorems' = Symtab.update (name, thms') theorems;

         val all_facts' = Facts.add_global (Sign.naming_of thy') (name, thms') all_facts;

       in

         (case Symtab.lookup theorems name of

           NONE => ()

         | SOME thms'' =>

             if Thm.eq_thms (thms', thms'') then warn_same name

             else warn_overwrite name);

         r := make_thms (space', theorems') all_facts';

         (thms', thy')

       end);

 (* add_thms(s) *)

 fun add_thms_atts pre_name ((bname, thms), atts) =

   enter_thms pre_name (name_thms false true)

     (foldl_map (Thm.theory_attributes atts)) (bname, thms);

 fun gen_add_thmss pre_name =

   fold_map (add_thms_atts pre_name);

 fun gen_add_thms pre_name args =

   apfst (map hd) o gen_add_thmss pre_name (map (apfst (apsnd single)) args);

 val add_thmss = gen_add_thmss (name_thms true true);

 val add_thms = gen_add_thms (name_thms true true);

 (* note_thmss(_i) *)

 local

 fun gen_note_thmss get tag = fold_map (fn ((bname, more_atts), ths_atts) => fn thy =>

   let

     fun app (x, (ths, atts)) = foldl_map (Thm.theory_attributes atts) (x, ths);

     val (thms, thy') = thy |> enter_thms

       (name_thmss true) (name_thms false true) (apsnd flat o foldl_map app)

       (bname, map (fn (ths, atts) => (get thy ths, surround tag (atts @ more_atts))) ths_atts);

   in ((bname, thms), thy') end);

 in

 fun note_thmss k = gen_note_thmss get_thms (kind k);

 fun note_thmss_i k = gen_note_thmss (K I) (kind k);

 fun note_thmss_grouped k g = gen_note_thmss (K I) (kind k #> group g);

 end;

 fun note kind (name, thm) =

   note_thmss_i kind [((name, []), [([thm], [])])]

   #>> (fn [(_, [thm])] => thm);

 fun note_thmss_qualified k path facts thy =

   thy

   |> Sign.add_path path

   |> Sign.no_base_names

   |> note_thmss_i k facts

   ||> Sign.restore_naming thy;

 (* store_thm *)

 fun store_thm ((bname, thm), atts) thy =

   let val ([th'], thy') = add_thms_atts (name_thms true true) ((bname, [thm]), atts) thy

   in (th', thy') end;

 (* smart_store_thms(_open) *)

 local

 fun smart_store _ (name, []) =

       error ("Cannot store empty list of theorems: " ^ quote name)

   | smart_store official (name, [thm]) =

       fst (enter_thms (name_thms true official) (name_thms false official) I (name, [thm])

         (Thm.theory_of_thm thm))

   | smart_store official (name, thms) =

       let val thy = Theory.merge_list (map Thm.theory_of_thm thms) in

         fst (enter_thms (name_thms true official) (name_thms false official) I (name, thms) thy)

       end;

 in

 val smart_store_thms = smart_store true;

 val smart_store_thms_open = smart_store false;

 end;

 (* forall_elim_var(s) -- belongs to drule.ML *)

 fun forall_elim_vars_aux strip_vars i th =

   let

     val {thy, tpairs, prop, ...} = Thm.rep_thm th;

     val add_used = Term.fold_aterms

       (fn Var ((x, j), _) => if i = j then insert (op =) x else I | _ => I);

     val used = fold (fn (t, u) => add_used t o add_used u) tpairs (add_used prop []);

     val vars = strip_vars prop;

     val cvars = (Name.variant_list used (map #1 vars), vars)

       |> ListPair.map (fn (x, (_, T)) => Thm.cterm_of thy (Var ((x, i), T)));

   in fold Thm.forall_elim cvars th end;

 val forall_elim_vars = forall_elim_vars_aux Term.strip_all_vars;

 fun forall_elim_var i th = forall_elim_vars_aux

   (fn Const ("all", _) $ Abs (a, T, _) => [(a, T)]

   | _ => raise THM ("forall_elim_vars", i, [th])) i th;

 (* store axioms as theorems *)

 local

   fun get_ax thy (name, _) = Thm.get_axiom_i thy (Sign.full_name thy name);

   fun get_axs thy named_axs = map (forall_elim_vars 0 o get_ax thy) named_axs;

   fun add_single add ((name, ax), atts) thy =

     let

       val named_ax = [(name, ax)];

       val thy' = add named_ax thy;

       val thm = hd (get_axs thy' named_ax);

     in apfst hd (gen_add_thms (K I) [((name, thm), atts)] thy') end;

   fun add_multi add ((name, axs), atts) thy =

     let

       val named_axs = name_multi name axs;

       val thy' = add named_axs thy;

       val thms = get_axs thy' named_axs;

     in apfst hd (gen_add_thmss (K I) [((name, thms), atts)] thy') end;

   fun add_singles add = fold_map (add_single add);

   fun add_multis add = fold_map (add_multi add);

 in

   val add_axioms           = add_singles Theory.add_axioms;

   val add_axioms_i         = add_singles Theory.add_axioms_i;

   val add_axiomss          = add_multis Theory.add_axioms;

   val add_axiomss_i        = add_multis Theory.add_axioms_i;

   val add_defs             = add_singles o Theory.add_defs false;

   val add_defs_i           = add_singles o Theory.add_defs_i false;

   val add_defs_unchecked   = add_singles o Theory.add_defs true;

   val add_defs_unchecked_i = add_singles o Theory.add_defs_i true;

 end;

 (*** the ProtoPure theory ***)

 val typ = SimpleSyntax.read_typ;

 val term = SimpleSyntax.read_term;

 val prop = SimpleSyntax.read_prop;

 val appl_syntax =

  [("_appl", typ "('b => 'a) => args => logic", Mixfix ("(1_/(1'(_')))", [1000, 0], 1000)),

   ("_appl", typ "('b => 'a) => args => aprop", Mixfix ("(1_/(1'(_')))", [1000, 0], 1000))];

 val applC_syntax =

  [("",       typ "'a => cargs",                  Delimfix "_"),

   ("_cargs", typ "'a => cargs => cargs",         Mixfix ("_/ _", [1000, 1000], 1000)),

   ("_applC", typ "('b => 'a) => cargs => logic", Mixfix ("(1_/ _)", [1000, 1000], 999)),

   ("_applC", typ "('b => 'a) => cargs => aprop", Mixfix ("(1_/ _)", [1000, 1000], 999))];

 val proto_pure =

   Context.pre_pure_thy

   |> Compress.init_data

   |> TheoremsData.init

   |> Sign.add_types

    [("fun", 2, NoSyn),

     ("prop", 0, NoSyn),

     ("itself", 1, NoSyn),

     ("dummy", 0, NoSyn)]

   |> Sign.add_nonterminals Syntax.basic_nonterms

   |> Sign.add_syntax_i

    [("_lambda",     typ "pttrns => 'a => logic",     Mixfix ("(3%_./ _)", [0, 3], 3)),

     ("_abs",        typ "'a",                        NoSyn),

     ("",            typ "'a => args",                Delimfix "_"),

     ("_args",       typ "'a => args => args",        Delimfix "_,/ _"),

     ("",            typ "id => idt",                 Delimfix "_"),

     ("_idtdummy",   typ "idt",                       Delimfix "'_"),

     ("_idtyp",      typ "id => type => idt",         Mixfix ("_::_", [], 0)),

     ("_idtypdummy", typ "type => idt",               Mixfix ("'_()::_", [], 0)),

     ("",            typ "idt => idt",                Delimfix "'(_')"),

     ("",            typ "idt => idts",               Delimfix "_"),

     ("_idts",       typ "idt => idts => idts",       Mixfix ("_/ _", [1, 0], 0)),

     ("",            typ "idt => pttrn",              Delimfix "_"),

     ("",            typ "pttrn => pttrns",           Delimfix "_"),

     ("_pttrns",     typ "pttrn => pttrns => pttrns", Mixfix ("_/ _", [1, 0], 0)),

     ("",            typ "id => aprop",               Delimfix "_"),

     ("",            typ "longid => aprop",           Delimfix "_"),

     ("",            typ "var => aprop",              Delimfix "_"),

     ("_DDDOT",      typ "aprop",                     Delimfix "..."),

     ("_aprop",      typ "aprop => prop",             Delimfix "PROP _"),

     ("_asm",        typ "prop => asms",              Delimfix "_"),

     ("_asms",       typ "prop => asms => asms",      Delimfix "_;/ _"),

     ("_bigimpl",    typ "asms => prop => prop",      Mixfix ("((3[| _ |])/ ==> _)", [0, 1], 1)),

     ("_ofclass",    typ "type => logic => prop",     Delimfix "(1OFCLASS/(1'(_,/ _')))"),

     ("_mk_ofclass", typ "dummy",                     NoSyn),

     ("_TYPE",       typ "type => logic",             Delimfix "(1TYPE/(1'(_')))"),

     ("",            typ "id => logic",               Delimfix "_"),

     ("",            typ "longid => logic",           Delimfix "_"),

     ("",            typ "var => logic",              Delimfix "_"),

     ("_DDDOT",      typ "logic",                     Delimfix "..."),

     ("_constify",   typ "num => num_const",          Delimfix "_"),

     ("_indexnum",   typ "num_const => index",        Delimfix "\\<^sub>_"),

     ("_index",      typ "logic => index",            Delimfix "(00\\<^bsub>_\\<^esub>)"),

     ("_indexdefault", typ "index",                   Delimfix ""),

     ("_indexvar",   typ "index",                     Delimfix "'\\<index>"),

     ("_struct",     typ "index => logic",            Mixfix ("\\<struct>_", [1000], 1000)),

     ("==>",         typ "prop => prop => prop",      Delimfix "op ==>"),

     (Term.dummy_patternN, typ "aprop",               Delimfix "'_")]

   |> Sign.add_syntax_i appl_syntax

   |> Sign.add_modesyntax_i (Symbol.xsymbolsN, true)

    [("fun",      typ "type => type => type",   Mixfix ("(_/ \\<Rightarrow> _)", [1, 0], 0)),

     ("_bracket", typ "types => type => type",  Mixfix ("([_]/ \\<Rightarrow> _)", [0, 0], 0)),

     ("_ofsort",  typ "tid => sort => type",    Mixfix ("_\\<Colon>_", [1000, 0], 1000)),

     ("_constrain", typ "'a => type => 'a",     Mixfix ("_\\<Colon>_", [4, 0], 3)),

     ("_idtyp",    typ "id => type => idt",     Mixfix ("_\\<Colon>_", [], 0)),

     ("_idtypdummy", typ "type => idt",         Mixfix ("'_()\\<Colon>_", [], 0)),

     ("_type_constraint_", typ "'a",            NoSyn),

     ("_lambda",  typ "pttrns => 'a => logic",  Mixfix ("(3\\<lambda>_./ _)", [0, 3], 3)),

     ("==",       typ "'a => 'a => prop",       InfixrName ("\\<equiv>", 2)),

     ("all_binder", typ "idts => prop => prop", Mixfix ("(3\\<And>_./ _)", [0, 0], 0)),

     ("==>",      typ "prop => prop => prop",   InfixrName ("\\<Longrightarrow>", 1)),

     ("_DDDOT",   typ "aprop",                  Delimfix "\\<dots>"),

     ("_bigimpl", typ "asms => prop => prop",   Mixfix ("((1\\<lbrakk>_\\<rbrakk>)/ \\<Longrightarrow> _)", [0, 1], 1)),

     ("_DDDOT",   typ "logic",                  Delimfix "\\<dots>")]

   |> Sign.add_modesyntax_i ("", false)

    [("prop", typ "prop => prop", Mixfix ("_", [0], 0)),

     ("ProtoPure.term", typ "'a => prop", Delimfix "TERM _"),

     ("ProtoPure.conjunction", typ "prop => prop => prop", InfixrName ("&&", 2))]

   |> Sign.add_modesyntax_i ("HTML", false)

    [("_lambda", typ "pttrns => 'a => logic", Mixfix ("(3\\<lambda>_./ _)", [0, 3], 3))]

   |> Sign.add_consts_i

    [("==", typ "'a => 'a => prop", InfixrName ("==", 2)),

     ("==>", typ "prop => prop => prop", Mixfix ("(_/ ==> _)", [2, 1], 1)),

     ("all", typ "('a => prop) => prop", Binder ("!!", 0, 0)),

     ("prop", typ "prop => prop", NoSyn),

     ("TYPE", typ "'a itself", NoSyn),

     (Term.dummy_patternN, typ "'a", Delimfix "'_")]

   |> Theory.add_deps "==" ("==", typ "'a => 'a => prop") []

   |> Theory.add_deps "==>" ("==>", typ "prop => prop => prop") []

   |> Theory.add_deps "all" ("all", typ "('a => prop) => prop") []

   |> Theory.add_deps "TYPE" ("TYPE", typ "'a itself") []

   |> Theory.add_deps Term.dummy_patternN (Term.dummy_patternN, typ "'a") []

   |> Sign.add_trfuns Syntax.pure_trfuns

   |> Sign.add_trfunsT Syntax.pure_trfunsT

   |> Sign.local_path

   |> Sign.add_consts_i

    [("term", typ "'a => prop", NoSyn),

     ("conjunction", typ "prop => prop => prop", NoSyn)]

   |> (add_defs_i false o map Thm.no_attributes)

    [("prop_def", prop "(CONST prop :: prop => prop) (A::prop) == A::prop"),

     ("term_def", prop "(CONST ProtoPure.term :: 'a => prop) (x::'a) == (!!A::prop. A ==> A)"),

     ("conjunction_def", prop "(A && B) == (!!C::prop. (A ==> B ==> C) ==> C)")] |> snd

   |> Sign.hide_consts false ["conjunction", "term"]

   |> add_thmss [(("nothing", []), [])] |> snd

   |> Theory.add_axioms_i Proofterm.equality_axms

   |> Theory.end_theory;

 structure ProtoPure =

 struct

   val thy = proto_pure;

   val prop_def = get_axiom thy "prop_def";

   val term_def = get_axiom thy "term_def";

   val conjunction_def = get_axiom thy "conjunction_def";

 end;

 end;

 structure BasicPureThy: BASIC_PURE_THY = PureThy;

 open BasicPureThy;