src/Pure/Isar/generic_target.ML

yet another attempt for terminology: foo_target_bar denotes an operation bar operating solely on the target context of target foo, foo_bar denotes a whole stack of operations to accomplish bar for target foo

(*  Title:      Pure/Isar/generic_target.ML
    Author:     Makarius
    Author:     Florian Haftmann, TU Muenchen

Common target infrastructure.
*)

signature GENERIC_TARGET =
sig
  (* declarations *)
  val standard_declaration: (int * int -> bool) -> declaration -> local_theory -> local_theory

  (* consts *)
  val standard_const: (int * int -> bool) -> Syntax.mode -> (binding * mixfix) * term ->
    local_theory -> local_theory

  (* background operations *)
  val background_foundation: ((binding * typ) * mixfix) * (binding * term) ->
    term list * term list -> local_theory -> (term * thm) * local_theory
  val background_declaration: declaration -> local_theory -> local_theory
  val background_abbrev: binding * term -> term list -> local_theory -> (term * term) * local_theory

  (* lifting primitives to local theory operations *)
  val define: (((binding * typ) * mixfix) * (binding * term) ->
      term list * term list -> local_theory -> (term * thm) * local_theory) ->
    bool -> (binding * mixfix) * (Attrib.binding * term) -> local_theory ->
    (term * (string * thm)) * local_theory
  val notes:
    (string -> (Attrib.binding * (thm list * Args.src list) list) list ->
      (Attrib.binding * (thm list * Args.src list) list) list -> local_theory -> local_theory) ->
    string -> (Attrib.binding * (thm list * Args.src list) list) list -> local_theory ->
    (string * thm list) list * local_theory
  val abbrev: (string * bool -> binding * mixfix -> term ->
      term list * term list -> local_theory -> local_theory) ->
    string * bool -> (binding * mixfix) * term -> local_theory -> (term * term) * local_theory

  (* theory operations *)
  val theory_foundation: ((binding * typ) * mixfix) * (binding * term) ->
    term list * term list -> local_theory -> (term * thm) * local_theory
  val theory_notes: string ->
    (Attrib.binding * (thm list * Args.src list) list) list ->
    (Attrib.binding * (thm list * Args.src list) list) list ->
    local_theory -> local_theory
  val theory_declaration: declaration -> local_theory -> local_theory
  val theory_abbrev: Syntax.mode -> (binding * mixfix) -> term -> term list * term list ->
    local_theory -> local_theory
  val theory_registration: string * morphism -> (morphism * bool) option -> morphism ->
    local_theory -> local_theory

  (* locale operations *)
  val locale_notes: string -> string ->
    (Attrib.binding * (thm list * Args.src list) list) list ->
    (Attrib.binding * (thm list * Args.src list) list) list ->
    local_theory -> local_theory
  val locale_target_declaration: string -> bool -> declaration -> local_theory -> local_theory
  val locale_target_const: string -> (morphism -> bool) -> Syntax.mode ->
    (binding * mixfix) * term -> local_theory -> local_theory
  val locale_const: string -> Syntax.mode -> (binding * mixfix) * term ->
    local_theory -> local_theory
  val locale_dependency: string -> string * morphism -> (morphism * bool) option -> morphism ->
    local_theory -> local_theory
end

structure Generic_Target: GENERIC_TARGET =
struct

(** notes **)

fun standard_facts lthy ctxt =
  Element.transform_facts (Local_Theory.standard_morphism lthy ctxt);

fun standard_notes pred kind facts lthy =
  Local_Theory.map_contexts (fn level => fn ctxt =>
    if pred (Local_Theory.level lthy, level)
    then Attrib.local_notes kind (standard_facts lthy ctxt facts) ctxt |> snd
    else ctxt) lthy;


(** declarations **)

fun standard_declaration pred decl lthy =
  Local_Theory.map_contexts (fn level => fn ctxt =>
    if pred (Local_Theory.level lthy, level)
    then Context.proof_map (Local_Theory.standard_form lthy ctxt decl) ctxt
    else ctxt) lthy;


(** consts **)

fun check_mixfix ctxt (b, extra_tfrees) mx =
  if null extra_tfrees then mx
  else
   (if Context_Position.is_visible ctxt then
      warning
        ("Additional type variable(s) in specification of " ^ Binding.print b ^ ": " ^
          commas (map (Syntax.string_of_typ ctxt o TFree) (sort_wrt #1 extra_tfrees)) ^
          (if mx = NoSyn then ""
           else "\nDropping mixfix syntax " ^ Pretty.string_of (Mixfix.pretty_mixfix mx)))
    else (); NoSyn);

fun check_mixfix_global (b, no_params) mx =
  if no_params orelse mx = NoSyn then mx
  else (warning ("Dropping global mixfix syntax: " ^ Binding.print b ^ " " ^
    Pretty.string_of (Mixfix.pretty_mixfix mx)); NoSyn);

fun const_decl phi_pred prmode ((b, mx), rhs) phi context =
  if phi_pred phi then
    let
      val b' = Morphism.binding phi b;
      val rhs' = Morphism.term phi rhs;
      val same_shape = Term.aconv_untyped (rhs, rhs');
      val const_alias =
        if same_shape then
          (case rhs' of
            Const (c, T) =>
              let
                val thy = Context.theory_of context;
                val ctxt = Context.proof_of context;
              in
                (case Type_Infer_Context.const_type ctxt c of
                  SOME T' => if Sign.typ_equiv thy (T, T') then SOME c else NONE
                | NONE => NONE)
              end
          | _ => NONE)
        else NONE;
    in
      case const_alias of
        SOME c =>
          context
          |> Context.mapping (Sign.const_alias b' c) (Proof_Context.const_alias b' c)
          |> Morphism.form (Proof_Context.generic_notation true prmode [(rhs', mx)])
      | NONE =>
          context
          |> Proof_Context.generic_add_abbrev Print_Mode.internal (b', Term.close_schematic_term rhs')
          |-> (fn (const as Const (c, _), _) => same_shape ?
                (Proof_Context.generic_revert_abbrev (#1 prmode) c #>
                 Morphism.form (Proof_Context.generic_notation true prmode [(const, mx)])))
    end
  else context;

fun standard_const pred prmode ((b, mx), rhs) =
  standard_declaration pred (const_decl (K true) prmode ((b, mx), rhs));


(** background primitives **)

fun background_foundation (((b, U), mx), (b_def, rhs)) (type_params, term_params) lthy =
  let
    val params = type_params @ term_params;
    val mx' = check_mixfix_global (b, null params) mx;

    val (const, lthy2) = lthy
      |> Local_Theory.background_theory_result (Sign.declare_const lthy ((b, U), mx'));
    val lhs = Term.list_comb (const, params);

    val ((_, def), lthy3) = lthy2
      |> Local_Theory.background_theory_result
        (Thm.add_def lthy2 false false
          (Thm.def_binding_optional b b_def, Logic.mk_equals (lhs, rhs)));
  in ((lhs, def), lthy3) end;

fun background_declaration decl lthy =
  let
    val theory_decl =
      Local_Theory.standard_form lthy
        (Proof_Context.init_global (Proof_Context.theory_of lthy)) decl;
  in Local_Theory.background_theory (Context.theory_map theory_decl) lthy end;

fun background_abbrev (b, global_rhs) params =
  Local_Theory.background_theory_result (Sign.add_abbrev Print_Mode.internal (b, global_rhs))
  #>> pairself (fn t => Term.list_comb (Logic.unvarify_global t, params))


(** lifting primitive to local theory operations **)

(* define *)

fun define foundation internal ((b, mx), ((b_def, atts), rhs)) lthy =
  let
    val thy = Proof_Context.theory_of lthy;
    val thy_ctxt = Proof_Context.init_global thy;

    (*term and type parameters*)
    val ((defs, _), rhs') = Thm.cterm_of thy rhs
      |> Local_Defs.export_cterm lthy thy_ctxt ||> Thm.term_of;

    val xs = Variable.add_fixed lthy rhs' [];
    val T = Term.fastype_of rhs;
    val tfreesT = Term.add_tfreesT T (fold (Term.add_tfreesT o #2) xs []);
    val extra_tfrees = rev (subtract (op =) tfreesT (Term.add_tfrees rhs []));
    val mx' = check_mixfix lthy (b, extra_tfrees) mx;

    val type_params = map (Logic.mk_type o TFree) extra_tfrees;
    val term_params = map Free (sort (Variable.fixed_ord lthy o pairself #1) xs);
    val params = type_params @ term_params;

    val U = map Term.fastype_of params ---> T;

    (*foundation*)
    val ((lhs', global_def), lthy2) = lthy
      |> foundation (((b, U), mx'), (b_def, rhs')) (type_params, term_params);

    (*local definition*)
    val ((lhs, local_def), lthy3) = lthy2
      |> Local_Defs.add_def ((b, NoSyn), lhs');

    (*result*)
    val def =
      Thm.transitive local_def global_def
      |> Local_Defs.contract lthy3 defs
          (Thm.cterm_of (Proof_Context.theory_of lthy3) (Logic.mk_equals (lhs, rhs)));
    val ([(res_name, [res])], lthy4) = lthy3
      |> Local_Theory.notes [((if internal then Binding.empty else b_def, atts), [([def], [])])];
  in ((lhs, (res_name, res)), lthy4) end;


(* notes *)

local

fun import_export_proof ctxt (name, raw_th) =
  let
    val thy = Proof_Context.theory_of ctxt;
    val thy_ctxt = Proof_Context.init_global thy;
    val certT = Thm.ctyp_of thy;
    val cert = Thm.cterm_of thy;

    (*export assumes/defines*)
    val th = Goal.norm_result ctxt raw_th;
    val ((defs, asms), th') = Local_Defs.export ctxt thy_ctxt th;
    val asms' = map (rewrite_rule ctxt (Drule.norm_hhf_eqs @ defs)) asms;

    (*export fixes*)
    val tfrees = map TFree (Thm.fold_terms Term.add_tfrees th' []);
    val frees = map Free (Thm.fold_terms Term.add_frees th' []);
    val (th'' :: vs) =
      (th' :: map (Drule.mk_term o cert) (map Logic.mk_type tfrees @ frees))
      |> Variable.export ctxt thy_ctxt
      |> Drule.zero_var_indexes_list;

    (*thm definition*)
    val result = Global_Theory.name_thm true true name th'';

    (*import fixes*)
    val (tvars, vars) =
      chop (length tfrees) (map (Thm.term_of o Drule.dest_term) vs)
      |>> map Logic.dest_type;

    val instT = map_filter (fn (TVar v, T) => SOME (v, T) | _ => NONE) (tvars ~~ tfrees);
    val inst = filter (is_Var o fst) (vars ~~ frees);
    val cinstT = map (pairself certT o apfst TVar) instT;
    val cinst = map (pairself (cert o Term.map_types (Term_Subst.instantiateT instT))) inst;
    val result' = Thm.instantiate (cinstT, cinst) result;

    (*import assumes/defines*)
    val result'' =
      (fold (curry op COMP) asms' result'
        handle THM _ => raise THM ("Failed to re-import result", 0, result' :: asms'))
      |> Local_Defs.contract ctxt defs (Thm.cprop_of th)
      |> Goal.norm_result ctxt
      |> Global_Theory.name_thm false false name;

  in (result'', result) end;

in

fun notes notes' kind facts lthy =
  let
    val facts' = facts
      |> map (fn (a, bs) => (a, Global_Theory.burrow_fact (Global_Theory.name_multi
          (Local_Theory.full_name lthy (fst a))) bs))
      |> Global_Theory.map_facts (import_export_proof lthy);
    val local_facts = Global_Theory.map_facts #1 facts';
    val global_facts = Global_Theory.map_facts #2 facts';
  in
    lthy
    |> notes' kind global_facts (Attrib.partial_evaluation lthy local_facts)
    |> Attrib.local_notes kind local_facts
  end;

end;


(* abbrev *)

fun abbrev abbrev' prmode ((b, mx), rhs) lthy =
  let
    val thy_ctxt = Proof_Context.init_global (Proof_Context.theory_of lthy);

    val rhs' = Assumption.export_term lthy (Local_Theory.target_of lthy) rhs;
    val term_params = map Free (sort (Variable.fixed_ord lthy o pairself #1) (Variable.add_fixed lthy rhs' []));
    val u = fold_rev lambda term_params rhs';
    val global_rhs = singleton (Variable.polymorphic thy_ctxt) u;

    val extra_tfrees =
      subtract (op =) (Term.add_tfreesT (Term.fastype_of u) []) (Term.add_tfrees u []);
    val mx' = check_mixfix lthy (b, extra_tfrees) mx;
    val type_params = map (Logic.mk_type o TFree) extra_tfrees;
  in
    lthy
    |> abbrev' prmode (b, mx') global_rhs (type_params, term_params)
    |> Proof_Context.add_abbrev Print_Mode.internal (b, rhs) |> snd
    |> Local_Defs.fixed_abbrev ((b, NoSyn), rhs)
  end;


(** theory operations **)

fun theory_foundation (((b, U), mx), (b_def, rhs)) (type_params, term_params) =
  background_foundation (((b, U), mx), (b_def, rhs)) (type_params, term_params)
  #-> (fn (lhs, def) => standard_const (op <>) Syntax.mode_default ((b, mx), lhs)
    #> pair (lhs, def));

fun theory_notes kind global_facts local_facts =
  Local_Theory.background_theory (Attrib.global_notes kind global_facts #> snd)
  #> standard_notes (op <>) kind local_facts;

fun theory_declaration decl =
  background_declaration decl #> standard_declaration (K true) decl;

fun theory_abbrev prmode (b, mx) global_rhs params =
  Local_Theory.background_theory_result
    (Sign.add_abbrev (#1 prmode) (b, global_rhs) #->
      (fn (lhs, _) =>  (* FIXME type_params!? *)
        Sign.notation true prmode [(lhs, check_mixfix_global (b, null (snd params)) mx)] #> pair lhs))
  #-> (fn lhs => standard_const (op <>) prmode
          ((b, if null (snd params) then NoSyn else mx), Term.list_comb (Logic.unvarify_global lhs, snd params)));

val theory_registration =
  Local_Theory.raw_theory o Context.theory_map ooo Locale.add_registration;


(** locale operations **)

fun locale_notes locale kind global_facts local_facts =
  Local_Theory.background_theory
    (Attrib.global_notes kind (Attrib.map_facts (K []) global_facts) #> snd) #>
  (fn lthy => lthy |>
    Local_Theory.target (fn ctxt => ctxt |>
      Locale.add_thmss locale kind (standard_facts lthy ctxt local_facts))) #>
  standard_notes (fn (this, other) => other <> 0 andalso this <> other) kind local_facts;

fun locale_target_declaration locale syntax decl lthy = lthy
  |> Local_Theory.target (fn ctxt => ctxt |>
    Locale.add_declaration locale syntax
      (Morphism.transform (Local_Theory.standard_morphism lthy ctxt) decl));

fun locale_target_const locale phi_pred prmode ((b, mx), rhs) =
  locale_target_declaration locale true (const_decl phi_pred prmode ((b, mx), rhs))

fun locale_const locale prmode ((b, mx), rhs) =
  locale_target_const locale (K true) prmode ((b, mx), rhs)
  #> standard_const (fn (this, other) => other <> 0 andalso this <> other) prmode ((b, mx), rhs);

fun locale_dependency locale dep_morph mixin export =
  (Local_Theory.raw_theory ooo Locale.add_dependency locale) dep_morph mixin export
  #> Local_Theory.activate_nonbrittle dep_morph mixin export;

end;