(*  Title:      Pure/Isar/code.ML

    ID:         $Id$

    Author:     Florian Haftmann, TU Muenchen

Abstract executable content of theory.  Management of data dependent on

executable content.  Cache assumes non-concurrent processing of a single theory.

*)

signature CODE =

sig

  val add_func: thm -> theory -> theory

  val add_nonlinear_func: thm -> theory -> theory

  val add_liberal_func: thm -> theory -> theory

  val add_default_func: thm -> theory -> theory

  val add_default_func_attr: Attrib.src

  val del_func: thm -> theory -> theory

  val del_funcs: string -> theory -> theory

  val add_funcl: string * (thm * bool) list Susp.T -> theory -> theory

  val map_pre: (MetaSimplifier.simpset -> MetaSimplifier.simpset) -> theory -> theory

  val map_post: (MetaSimplifier.simpset -> MetaSimplifier.simpset) -> theory -> theory

  val add_inline: thm -> theory -> theory

  val del_inline: thm -> theory -> theory

  val add_post: thm -> theory -> theory

  val del_post: thm -> theory -> theory

  val add_functrans: string * (theory -> thm list -> thm list option) -> theory -> theory

  val del_functrans: string -> theory -> theory

  val add_datatype: (string * typ) list -> theory -> theory

  val add_datatype_cmd: string list -> theory -> theory

  val type_interpretation:

    (string * ((string * sort) list * (string * typ list) list)

      -> theory -> theory) -> theory -> theory

  val add_case: thm -> theory -> theory

  val add_undefined: string -> theory -> theory

  val purge_data: theory -> theory

  val coregular_algebra: theory -> Sorts.algebra

  val operational_algebra: theory -> (sort -> sort) * Sorts.algebra

  val these_funcs: theory -> string -> (thm * bool) list

  val get_datatype: theory -> string -> ((string * sort) list * (string * typ list) list)

  val get_datatype_of_constr: theory -> string -> string option

  val get_case_data: theory -> string -> (int * string list) option

  val is_undefined: theory -> string -> bool

  val default_typ: theory -> string -> (string * sort) list * typ

  val preprocess_conv: cterm -> thm

  val preprocess_term: theory -> term -> term

  val postprocess_conv: cterm -> thm

  val postprocess_term: theory -> term -> term

  val add_attribute: string * (Args.T list -> attribute * Args.T list) -> theory -> theory

  val print_codesetup: theory -> unit

end;

signature CODE_DATA_ARGS =

sig

  type T

  val empty: T

  val purge: theory -> string list -> T -> T

end;

signature CODE_DATA =

sig

  type T

  val get: theory -> T

  val change: theory -> (T -> T) -> T

  val change_yield: theory -> (T -> 'a * T) -> 'a * T

end;

signature PRIVATE_CODE =

sig

  include CODE

  val declare_data: Object.T -> (theory -> string list -> Object.T -> Object.T)

    -> serial

  val get_data: serial * ('a -> Object.T) * (Object.T -> 'a)

    -> theory -> 'a

  val change_data: serial * ('a -> Object.T) * (Object.T -> 'a)

    -> theory -> ('a -> 'a) -> 'a

  val change_yield_data: serial * ('a -> Object.T) * (Object.T -> 'a)

    -> theory -> ('a -> 'b * 'a) -> 'b * 'a

end;

structure Code : PRIVATE_CODE =

struct

(** code attributes **)

structure CodeAttr = TheoryDataFun (

  type T = (string * (Args.T list -> attribute * Args.T list)) list;

  val empty = [];

  val copy = I;

  val extend = I;

  fun merge _ = AList.merge (op = : string * string -> bool) (K true);

);

fun add_attribute (attr as (name, _)) =

  let

    fun add_parser ("", parser) attrs = attrs @ [("", parser)]

      | add_parser (name, parser) attrs = (name, Args.$$$ name |-- parser) :: attrs;

    fun error "" = error ("Code attribute already declared")

      | error name = error ("Code attribute " ^ name ^ " already declared")

  in CodeAttr.map (fn attrs => if AList.defined (op =) attrs name

    then error name else add_parser attr attrs)

  end;

val _ =

  let

    val code_attr = Attrib.syntax (Scan.peek (fn context =>

      List.foldr op || Scan.fail (map snd (CodeAttr.get (Context.theory_of context)))));

  in

    Context.>> (Context.map_theory

      (Attrib.add_attributes

        [("code", code_attr, "declare theorems for code generation")]))

  end;

(** logical and syntactical specification of executable code **)

(* defining equations with linear flag, default flag and lazy theorems *)

fun pretty_lthms ctxt r = case Susp.peek r

 of SOME thms => map (ProofContext.pretty_thm ctxt o fst) thms

  | NONE => [Pretty.str "[...]"];

fun certificate thy f r =

  case Susp.peek r

   of SOME thms => (Susp.value o burrow_fst (f thy)) thms

    | NONE => let

        val thy_ref = Theory.check_thy thy;

      in Susp.delay (fn () => (burrow_fst (f (Theory.deref thy_ref)) o Susp.force) r) end;

fun add_drop_redundant (thm, linear) thms =

  let

    val thy = Thm.theory_of_thm thm;

    val args_of = snd o strip_comb o fst o Logic.dest_equals o Thm.plain_prop_of;

    val args = args_of thm;

    fun matches_args args' = length args <= length args' andalso

      Pattern.matchess thy (args, curry Library.take (length args) args');

    fun drop (thm', _) = if matches_args (args_of thm') then 

      (warning ("Code generator: dropping redundant defining equation\n" ^ Display.string_of_thm thm'); true)

      else false;

  in (thm, linear) :: filter_out drop thms end;

fun add_thm _ thm (false, thms) = (false, Susp.map_force (add_drop_redundant thm) thms)

  | add_thm true thm (true, thms) = (true, Susp.map_force (fn thms => thms @ [thm]) thms)

  | add_thm false thm (true, thms) = (false, Susp.value [thm]);

fun add_lthms lthms _ = (false, lthms);

fun del_thm thm = (apsnd o Susp.map_force) (remove (eq_fst Thm.eq_thm_prop) (thm, true));

fun merge_defthms ((true, _), defthms2) = defthms2

  | merge_defthms (defthms1 as (false, _), (true, _)) = defthms1

  | merge_defthms ((false, _), defthms2 as (false, _)) = defthms2;

(* syntactic datatypes *)

val eq_string = op = : string * string -> bool;

fun eq_dtyp ((vs1, cs1), (vs2, cs2)) = 

  gen_eq_set (eq_pair eq_string (gen_eq_set eq_string)) (vs1, vs2)

    andalso gen_eq_set (eq_fst eq_string) (cs1, cs2);

fun merge_dtyps (tabs as (tab1, tab2)) =

  let

    fun join _ (cos as (_, cos2)) = if eq_dtyp cos then raise Symtab.SAME else cos2;

  in Symtab.join join tabs end;

(* specification data *)

datatype spec = Spec of {

  funcs: (bool * (thm * bool) list Susp.T) Symtab.table,

  dtyps: ((string * sort) list * (string * typ list) list) Symtab.table,

  cases: (int * string list) Symtab.table * unit Symtab.table

};

fun mk_spec (funcs, (dtyps, cases)) =

  Spec { funcs = funcs, dtyps = dtyps, cases = cases };

fun map_spec f (Spec { funcs = funcs, dtyps = dtyps, cases = cases }) =

  mk_spec (f (funcs, (dtyps, cases)));

fun merge_spec (Spec { funcs = funcs1, dtyps = dtyps1, cases = (cases1, undefs1) },

  Spec { funcs = funcs2, dtyps = dtyps2, cases = (cases2, undefs2) }) =

  let

    val funcs = Symtab.join (K merge_defthms) (funcs1, funcs2);

    val dtyps = merge_dtyps (dtyps1, dtyps2);

    val cases = (Symtab.merge (K true) (cases1, cases2),

      Symtab.merge (K true) (undefs1, undefs2));

  in mk_spec (funcs, (dtyps, cases)) end;

(* pre- and postprocessor *)

datatype thmproc = Thmproc of {

  pre: MetaSimplifier.simpset,

  post: MetaSimplifier.simpset,

  functrans: (string * (serial * (theory -> thm list -> thm list option))) list

};

fun mk_thmproc ((pre, post), functrans) =

  Thmproc { pre = pre, post = post, functrans = functrans };

fun map_thmproc f (Thmproc { pre, post, functrans }) =

  mk_thmproc (f ((pre, post), functrans));

fun merge_thmproc (Thmproc { pre = pre1, post = post1, functrans = functrans1 },

  Thmproc { pre = pre2, post = post2, functrans = functrans2 }) =

    let

      val pre = MetaSimplifier.merge_ss (pre1, pre2);

      val post = MetaSimplifier.merge_ss (post1, post2);

      val functrans = AList.merge (op =) (eq_fst (op =)) (functrans1, functrans2);

    in mk_thmproc ((pre, post), functrans) end;

datatype exec = Exec of {

  thmproc: thmproc,

  spec: spec

};

(* code setup data *)

fun mk_exec (thmproc, spec) =

  Exec { thmproc = thmproc, spec = spec };

fun map_exec f (Exec { thmproc = thmproc, spec = spec }) =

  mk_exec (f (thmproc, spec));

fun merge_exec (Exec { thmproc = thmproc1, spec = spec1 },

  Exec { thmproc = thmproc2, spec = spec2 }) =

  let

    val thmproc = merge_thmproc (thmproc1, thmproc2);

    val spec = merge_spec (spec1, spec2);

  in mk_exec (thmproc, spec) end;

val empty_exec = mk_exec (mk_thmproc ((MetaSimplifier.empty_ss, MetaSimplifier.empty_ss), []),

  mk_spec (Symtab.empty, (Symtab.empty, (Symtab.empty, Symtab.empty))));

fun the_thmproc (Exec { thmproc = Thmproc x, ...}) = x;

fun the_spec (Exec { spec = Spec x, ...}) = x;

val the_funcs = #funcs o the_spec;

val the_dtyps = #dtyps o the_spec;

val the_cases = #cases o the_spec;

val map_thmproc = map_exec o apfst o map_thmproc;

val map_funcs = map_exec o apsnd o map_spec o apfst;

val map_dtyps = map_exec o apsnd o map_spec o apsnd o apfst;

val map_cases = map_exec o apsnd o map_spec o apsnd o apsnd;

(* data slots dependent on executable content *)

(*private copy avoids potential conflict of table exceptions*)

structure Datatab = TableFun(type key = int val ord = int_ord);

local

type kind = {

  empty: Object.T,

  purge: theory -> string list -> Object.T -> Object.T

};

val kinds = ref (Datatab.empty: kind Datatab.table);

val kind_keys = ref ([]: serial list);

fun invoke f k = case Datatab.lookup (! kinds) k

 of SOME kind => f kind

  | NONE => sys_error "Invalid code data identifier";

in

fun declare_data empty purge =

  let

    val k = serial ();

    val kind = {empty = empty, purge = purge};

    val _ = change kinds (Datatab.update (k, kind));

    val _ = change kind_keys (cons k);

  in k end;

fun invoke_init k = invoke (fn kind => #empty kind) k;

fun invoke_purge_all thy cs =

  fold (fn k => Datatab.map_entry k

    (invoke (fn kind => #purge kind thy cs) k)) (! kind_keys);

end; (*local*)

(** theory store **)

local

type data = Object.T Datatab.table;

val empty_data = Datatab.empty : data;

structure CodeData = TheoryDataFun

(

  type T = exec * data ref;

  val empty = (empty_exec, ref empty_data);

  fun copy (exec, data) = (exec, ref (! data));

  val extend = copy;

  fun merge pp ((exec1, data1), (exec2, data2)) =

    (merge_exec (exec1, exec2), ref empty_data);

);

val _ = Context.>> (Context.map_theory CodeData.init);

fun thy_data f thy = f ((snd o CodeData.get) thy);

fun get_ensure_init kind data_ref =

  case Datatab.lookup (! data_ref) kind

   of SOME x => x

    | NONE => let val y = invoke_init kind

        in (change data_ref (Datatab.update (kind, y)); y) end;

in

(* access to executable content *)

val the_exec = fst o CodeData.get;

fun complete_class_params thy cs =

  fold (fn c => case AxClass.inst_of_param thy c

   of NONE => insert (op =) c

    | SOME (c', _) => insert (op =) c' #> insert (op =) c) cs [];

fun map_exec_purge touched f thy =

  CodeData.map (fn (exec, data) => (f exec, ref (case touched

   of SOME cs => invoke_purge_all thy (complete_class_params thy cs) (! data)

    | NONE => empty_data))) thy;

val purge_data = (CodeData.map o apsnd) (K (ref empty_data));

(* access to data dependent on abstract executable content *)

fun get_data (kind, _, dest) = thy_data (get_ensure_init kind #> dest);

fun change_data (kind, mk, dest) =

  let

    fun chnge data_ref f =

      let

        val data = get_ensure_init kind data_ref;

        val data' = f (dest data);

      in (change data_ref (Datatab.update (kind, mk data')); data') end;

  in thy_data chnge end;

fun change_yield_data (kind, mk, dest) =

  let

    fun chnge data_ref f =

      let

        val data = get_ensure_init kind data_ref;

        val (x, data') = f (dest data);

      in (x, (change data_ref (Datatab.update (kind, mk data')); data')) end;

  in thy_data chnge end;

end; (*local*)

(* print executable content *)

fun print_codesetup thy =

  let

    val ctxt = ProofContext.init thy;

    val exec = the_exec thy;

    fun pretty_func (s, (_, lthms)) =

      (Pretty.block o Pretty.fbreaks) (

        Pretty.str s :: pretty_lthms ctxt lthms

      );

    fun pretty_dtyp (s, []) =

          Pretty.str s

      | pretty_dtyp (s, cos) =

          (Pretty.block o Pretty.breaks) (

            Pretty.str s

            :: Pretty.str "="

            :: separate (Pretty.str "|") (map (fn (c, []) => Pretty.str c

                 | (c, tys) =>

                     (Pretty.block o Pretty.breaks)

                        (Pretty.str (Code_Unit.string_of_const thy c)

                          :: Pretty.str "of"

                          :: map (Pretty.quote o Syntax.pretty_typ_global thy) tys)) cos)

          );

    val pre = (#pre o the_thmproc) exec;

    val post = (#post o the_thmproc) exec;

    val functrans = (map fst o #functrans o the_thmproc) exec;

    val funcs = the_funcs exec

      |> Symtab.dest

      |> (map o apfst) (Code_Unit.string_of_const thy)

      |> sort (string_ord o pairself fst);

    val dtyps = the_dtyps exec

      |> Symtab.dest

      |> map (fn (dtco, (vs, cos)) =>

          (Syntax.string_of_typ_global thy (Type (dtco, map TFree vs)), cos))

      |> sort (string_ord o pairself fst)

  in

    (Pretty.writeln o Pretty.chunks) [

      Pretty.block (

        Pretty.str "defining equations:"

        :: Pretty.fbrk

        :: (Pretty.fbreaks o map pretty_func) funcs

      ),

      Pretty.block [

        Pretty.str "preprocessing simpset:",

        Pretty.fbrk,

        MetaSimplifier.pretty_ss pre

      ],

      Pretty.block [

        Pretty.str "postprocessing simpset:",

        Pretty.fbrk,

        MetaSimplifier.pretty_ss post

      ],

      Pretty.block (

        Pretty.str "function transformers:"

        :: Pretty.fbrk

        :: (Pretty.fbreaks o map Pretty.str) functrans

      ),

      Pretty.block (

        Pretty.str "datatypes:"

        :: Pretty.fbrk

        :: (Pretty.fbreaks o map pretty_dtyp) dtyps

      )

    ]

  end;

(** theorem transformation and certification **)

fun const_of thy = dest_Const o fst o strip_comb o fst o Logic.dest_equals

  o ObjectLogic.drop_judgment thy o Thm.plain_prop_of;

fun const_of_func thy = AxClass.unoverload_const thy o const_of thy;

fun common_typ_funcs [] = []

  | common_typ_funcs [thm] = [thm]

  | common_typ_funcs (thms as thm :: _) = (*FIXME is too general*)

      let

        val thy = Thm.theory_of_thm thm;

        fun incr_thm thm max =

          let

            val thm' = incr_indexes max thm;

            val max' = Thm.maxidx_of thm' + 1;

          in (thm', max') end;

        val (thms', maxidx) = fold_map incr_thm thms 0;

        val ty1 :: tys = map (snd o const_of thy) thms';

        fun unify ty env = Sign.typ_unify thy (ty1, ty) env

          handle Type.TUNIFY =>

            error ("Type unificaton failed, while unifying defining equations\n"

            ^ (cat_lines o map Display.string_of_thm) thms

            ^ "\nwith types\n"

            ^ (cat_lines o map (Code_Unit.string_of_typ thy)) (ty1 :: tys));

        val (env, _) = fold unify tys (Vartab.empty, maxidx)

        val instT = Vartab.fold (fn (x_i, (sort, ty)) =>

          cons (Thm.ctyp_of thy (TVar (x_i, sort)), Thm.ctyp_of thy ty)) env [];

      in map (Thm.instantiate (instT, [])) thms' end;

fun certify_const thy const thms =

  let

    fun cert thm = if const = const_of_func thy thm

      then thm else error ("Wrong head of defining equation,\nexpected constant "

        ^ Code_Unit.string_of_const thy const ^ "\n" ^ Display.string_of_thm thm)

  in map cert thms end;

(** operational sort algebra and class discipline **)

local

fun aggr_neutr f y [] = y

  | aggr_neutr f y (x::xs) = aggr_neutr f (f y x) xs;

fun aggregate f [] = NONE

  | aggregate f (x::xs) = SOME (aggr_neutr f x xs);

fun inter_sorts algebra =

  aggregate (map2 (curry (Sorts.inter_sort algebra)));

fun specific_constraints thy (class, tyco) =

  let

    val vs = Name.invents Name.context "" (Sign.arity_number thy tyco);

    val classparams = (map fst o these o try (#params o AxClass.get_info thy)) class;

    val funcs = classparams

      |> map_filter (fn c => try (AxClass.param_of_inst thy) (c, tyco))

      |> map (Symtab.lookup ((the_funcs o the_exec) thy))

      |> (map o Option.map) (map fst o Susp.force o snd)

      |> maps these

      |> map (Thm.transfer thy);

    fun sorts_of [Type (_, tys)] = map (snd o dest_TVar) tys

      | sorts_of tys = map (snd o dest_TVar) tys;

    val sorts = map (sorts_of o Sign.const_typargs thy o const_of thy) funcs;

  in sorts end;

fun weakest_constraints thy algebra (class, tyco) =

  let

    val all_superclasses = Sorts.complete_sort algebra [class];

  in case inter_sorts algebra (maps (fn class => specific_constraints thy (class, tyco)) all_superclasses)

   of SOME sorts => sorts

    | NONE => Sorts.mg_domain algebra tyco [class]

  end;

fun strongest_constraints thy algebra (class, tyco) =

  let

    val all_subclasses = class :: Graph.all_preds ((#classes o Sorts.rep_algebra) algebra) [class];

    val inst_subclasses = filter (can (Sorts.mg_domain algebra tyco) o single) all_subclasses;

  in case inter_sorts algebra (maps (fn class => specific_constraints thy (class, tyco)) inst_subclasses)

   of SOME sorts => sorts

    | NONE => replicate

        (Sign.arity_number thy tyco) (Sorts.minimize_sort algebra (Sorts.all_classes algebra))

  end;

fun get_algebra thy (class, tyco) =

  let

    val base_algebra = Sign.classes_of thy;

  in if can (Sorts.mg_domain base_algebra tyco) [class]

    then base_algebra

    else let

      val superclasses = Sorts.super_classes base_algebra class;

      val sorts = inter_sorts base_algebra

          (map_filter (fn class => try (Sorts.mg_domain base_algebra tyco) [class]) superclasses)

        |> the_default (replicate (Sign.arity_number thy tyco) [])

    in

      base_algebra

      |> Sorts.add_arities (Syntax.pp_global thy) (tyco, [(class, sorts)])

    end

  end;

fun gen_classparam_typ constr thy class (c, tyco) = 

  let

    val algebra = get_algebra thy (class, tyco);

    val cs = these (try (#params o AxClass.get_info thy) class);

    val SOME ty = AList.lookup (op =) cs c;

    val sort_args = Name.names (Name.declare Name.aT Name.context) Name.aT

      (constr thy algebra (class, tyco));

    val ty_inst = Type (tyco, map TFree sort_args);

  in Logic.varifyT (map_type_tfree (K ty_inst) ty) end;

fun retrieve_algebra thy operational =

  Sorts.subalgebra (Syntax.pp_global thy) operational

    (weakest_constraints thy (Sign.classes_of thy))

    (Sign.classes_of thy);

in

fun coregular_algebra thy = retrieve_algebra thy (K true) |> snd;

fun operational_algebra thy =

  let

    fun add_iff_operational class =

      can (AxClass.get_info thy) class ? cons class;

    val operational_classes = fold add_iff_operational (Sign.all_classes thy) []

  in retrieve_algebra thy (member (op =) operational_classes) end;

val classparam_weakest_typ = gen_classparam_typ weakest_constraints;

val classparam_strongest_typ = gen_classparam_typ strongest_constraints;

fun assert_func_typ thm =

  let

    val thy = Thm.theory_of_thm thm;

    fun check_typ_classparam tyco (c, thm) =

          let

            val SOME class = AxClass.class_of_param thy c;

            val (_, ty) = const_of thy thm;

            val ty_decl = classparam_weakest_typ thy class (c, tyco);

            val ty_strongest = classparam_strongest_typ thy class (c, tyco);

            fun constrain thm = 

              let

                val max = Thm.maxidx_of thm + 1;

                val ty_decl' = Logic.incr_tvar max ty_decl;

                val (_, ty') = const_of thy thm;

                val (env, _) = Sign.typ_unify thy (ty_decl', ty') (Vartab.empty, max);

                val instT = Vartab.fold (fn (x_i, (sort, ty)) =>

                  cons (Thm.ctyp_of thy (TVar (x_i, sort)), Thm.ctyp_of thy ty)) env [];

              in Thm.instantiate (instT, []) thm end;

          in if Sign.typ_instance thy (ty_strongest, ty)

            then if Sign.typ_instance thy (ty, ty_decl)

            then thm

            else (warning ("Constraining type\n" ^ Code_Unit.string_of_typ thy ty

              ^ "\nof defining equation\n"

              ^ Display.string_of_thm thm

              ^ "\nto permitted most general type\n"

              ^ Code_Unit.string_of_typ thy ty_decl);

              constrain thm)

            else Code_Unit.bad_thm ("Type\n" ^ Code_Unit.string_of_typ thy ty

              ^ "\nof defining equation\n"

              ^ Display.string_of_thm thm

              ^ "\nis incompatible with permitted least general type\n"

              ^ Code_Unit.string_of_typ thy ty_strongest)

          end;

    fun check_typ_fun (c, thm) =

      let

        val (_, ty) = const_of thy thm;

        val ty_decl = Sign.the_const_type thy c;

      in if Sign.typ_equiv thy (Type.strip_sorts ty_decl, Type.strip_sorts ty)

        then thm

        else Code_Unit.bad_thm ("Type\n" ^ Code_Unit.string_of_typ thy ty

           ^ "\nof defining equation\n"

           ^ Display.string_of_thm thm

           ^ "\nis incompatible with declared function type\n"

           ^ Code_Unit.string_of_typ thy ty_decl)

      end;

    fun check_typ (c, thm) =

      case AxClass.inst_of_param thy c

       of SOME (c, tyco) => check_typ_classparam tyco (c, thm)

        | NONE => check_typ_fun (c, thm);

  in check_typ (const_of_func thy thm, thm) end;

fun mk_func linear = Code_Unit.error_thm (assert_func_typ o Code_Unit.mk_func linear);

val mk_liberal_func = Code_Unit.warning_thm (assert_func_typ o Code_Unit.mk_func true);

val mk_syntactic_func = Code_Unit.warning_thm (assert_func_typ o Code_Unit.mk_func false);

val mk_default_func = Code_Unit.try_thm (assert_func_typ o Code_Unit.mk_func true);

end; (*local*)

(** interfaces and attributes **)

fun delete_force msg key xs =

  if AList.defined (op =) xs key then AList.delete (op =) key xs

  else error ("No such " ^ msg ^ ": " ^ quote key);

fun get_datatype thy tyco =

  case Symtab.lookup ((the_dtyps o the_exec) thy) tyco

   of SOME spec => spec

    | NONE => Sign.arity_number thy tyco

        |> Name.invents Name.context Name.aT

        |> map (rpair [])

        |> rpair [];

fun get_datatype_of_constr thy c =

  case (snd o strip_type o Sign.the_const_type thy) c

   of Type (tyco, _) => if member (op =)

       ((the_default [] o Option.map (map fst o snd) o Symtab.lookup ((the_dtyps o the_exec) thy)) tyco) c

       then SOME tyco else NONE

    | _ => NONE;

fun get_constr_typ thy c =

  case get_datatype_of_constr thy c

   of SOME tyco => let

          val (vs, cos) = get_datatype thy tyco;

          val SOME tys = AList.lookup (op =) cos c;

          val ty = tys ---> Type (tyco, map TFree vs);

        in SOME (Logic.varifyT ty) end

    | NONE => NONE;

val get_case_data = Symtab.lookup o fst o the_cases o the_exec;

val is_undefined = Symtab.defined o snd o the_cases o the_exec;

fun gen_add_func linear strict default thm thy =

  case (if strict then SOME o mk_func linear else mk_liberal_func) thm

   of SOME func =>

        let

          val c = const_of_func thy func;

          val _ = if strict andalso (is_some o AxClass.class_of_param thy) c

            then error ("Rejected polymorphic equation for overloaded constant:\n"

              ^ Display.string_of_thm thm)

            else ();

          val _ = if strict andalso (is_some o get_datatype_of_constr thy) c

            then error ("Rejected equation for datatype constructor:\n"

              ^ Display.string_of_thm func)

            else ();

        in

          (map_exec_purge (SOME [c]) o map_funcs) (Symtab.map_default

            (c, (true, Susp.value [])) (add_thm default (func, linear))) thy

        end

    | NONE => thy;

val add_func = gen_add_func true true false;

val add_liberal_func = gen_add_func true false false;

val add_default_func = gen_add_func true false true;

val add_nonlinear_func = gen_add_func false true false;

fun del_func thm thy = case mk_syntactic_func thm

 of SOME func => let

        val c = const_of_func thy func;

      in map_exec_purge (SOME [c]) (map_funcs

        (Symtab.map_entry c (del_thm func))) thy

      end

  | NONE => thy;

fun del_funcs c = map_exec_purge (SOME [c])

  (map_funcs (Symtab.map_entry c (K (false, Susp.value []))));

fun add_funcl (c, lthms) thy =

  let

    val lthms' = certificate thy (fn thy => certify_const thy c) lthms;

      (*FIXME must check compatibility with sort algebra;

        alas, naive checking results in non-termination!*)

  in

    map_exec_purge (SOME [c])

      (map_funcs (Symtab.map_default (c, (true, Susp.value []))

        (add_lthms lthms'))) thy

  end;

val add_default_func_attr = Attrib.internal (fn _ => Thm.declaration_attribute

  (fn thm => Context.mapping (add_default_func thm) I));

structure TypeInterpretation = InterpretationFun(type T = string * serial val eq = eq_snd (op =) : T * T -> bool);

fun add_datatype raw_cs thy =

  let

    val cs = map (fn c_ty as (_, ty) => (AxClass.unoverload_const thy c_ty, ty)) raw_cs;

    val (tyco, vs_cos) = Code_Unit.constrset_of_consts thy cs;

    val cs' = map fst (snd vs_cos);

    val purge_cs = case Symtab.lookup ((the_dtyps o the_exec) thy) tyco

     of SOME (vs, cos) => if null cos then NONE else SOME (cs' @ map fst cos)

      | NONE => NONE;

  in

    thy

    |> map_exec_purge purge_cs (map_dtyps (Symtab.update (tyco, vs_cos))

        #> map_funcs (fold (Symtab.delete_safe o fst) cs))

    |> TypeInterpretation.data (tyco, serial ())

  end;

fun type_interpretation f =  TypeInterpretation.interpretation

  (fn (tyco, _) => fn thy => f (tyco, get_datatype thy tyco) thy);

fun add_datatype_cmd raw_cs thy =

  let

    val cs = map (Code_Unit.read_bare_const thy) raw_cs;

  in add_datatype cs thy end;

fun add_case thm thy =

  let

    val entry as (c, _) = Code_Unit.case_cert thm;

  in

    (map_exec_purge (SOME [c]) o map_cases o apfst) (Symtab.update entry) thy

  end;

fun add_undefined c thy =

  (map_exec_purge (SOME [c]) o map_cases o apsnd) (Symtab.update (c, ())) thy;

val map_pre = map_exec_purge NONE o map_thmproc o apfst o apfst;

val map_post = map_exec_purge NONE o map_thmproc o apfst o apsnd;

fun add_inline thm thy = (map_pre o MetaSimplifier.add_simp)

  (Code_Unit.error_thm Code_Unit.mk_rew thm) thy;

    (*fully applied in order to get right context for mk_rew!*)

fun del_inline thm thy = (map_pre o MetaSimplifier.del_simp)

  (Code_Unit.error_thm Code_Unit.mk_rew thm) thy;

    (*fully applied in order to get right context for mk_rew!*)

fun add_post thm thy = (map_post o MetaSimplifier.add_simp)

  (Code_Unit.error_thm Code_Unit.mk_rew thm) thy;

    (*fully applied in order to get right context for mk_rew!*)

fun del_post thm thy = (map_post o MetaSimplifier.del_simp)

  (Code_Unit.error_thm Code_Unit.mk_rew thm) thy;

    (*fully applied in order to get right context for mk_rew!*)

fun add_functrans (name, f) =

  (map_exec_purge NONE o map_thmproc o apsnd)

    (AList.update (op =) (name, (serial (), f)));

fun del_functrans name =

  (map_exec_purge NONE o map_thmproc o apsnd)

    (delete_force "function transformer" name);

val _ = Context.>> (Context.map_theory

  (let

    fun mk_attribute f = Thm.declaration_attribute (fn thm => Context.mapping (f thm) I);

    fun add_simple_attribute (name, f) =

      add_attribute (name, Scan.succeed (mk_attribute f));

    fun add_del_attribute (name, (add, del)) =

      add_attribute (name, Args.del |-- Scan.succeed (mk_attribute del)

        || Scan.succeed (mk_attribute add))

  in

    TypeInterpretation.init

    #> add_del_attribute ("func", (add_func, del_func))

    #> add_simple_attribute ("nbe", add_nonlinear_func)

    #> add_del_attribute ("inline", (add_inline, del_inline))

    #> add_del_attribute ("post", (add_post, del_post))

  end));

(** post- and preprocessing **)

local

fun apply_functrans thy [] = []

  | apply_functrans thy (thms as thm :: _) =

      let

        val const = const_of_func thy thm;

        val functrans = (map (fn (_, (_, f)) => f thy) o #functrans

          o the_thmproc o the_exec) thy;

        val thms' = perhaps (perhaps_loop (perhaps_apply functrans)) thms;

      in certify_const thy const thms' end;

fun rhs_conv conv thm =

  let

    val thm' = (conv o Thm.rhs_of) thm;

  in Thm.transitive thm thm' end

fun term_of_conv thy f =

  Thm.cterm_of thy

  #> f

  #> Thm.prop_of

  #> Logic.dest_equals

  #> snd;

in

fun preprocess thy thms =

  let

    val pre = (Simplifier.theory_context thy o #pre o the_thmproc o the_exec) thy;

  in

    thms

    |> apply_functrans thy

    |> map (Code_Unit.rewrite_func pre)

    (*FIXME - must check here: rewrite rule, defining equation, proper constant *)

    |> map (AxClass.unoverload thy)

    |> common_typ_funcs

  end;

fun preprocess_conv ct =

  let

    val thy = Thm.theory_of_cterm ct;

    val pre = (Simplifier.theory_context thy o #pre o the_thmproc o the_exec) thy;

  in

    ct

    |> Simplifier.rewrite pre

    |> rhs_conv (AxClass.unoverload_conv thy)

  end;

fun preprocess_term thy = term_of_conv thy preprocess_conv;

fun postprocess_conv ct =

  let

    val thy = Thm.theory_of_cterm ct;

    val post = (Simplifier.theory_context thy o #post o the_thmproc o the_exec) thy;

  in

    ct

    |> AxClass.overload_conv thy

    |> rhs_conv (Simplifier.rewrite post)

  end;

fun postprocess_term thy = term_of_conv thy postprocess_conv;

end; (*local*)

fun default_typ_proto thy c = case AxClass.inst_of_param thy c

 of SOME (c, tyco) => classparam_weakest_typ thy ((the o AxClass.class_of_param thy) c)

      (c, tyco) |> SOME

  | NONE => (case AxClass.class_of_param thy c

     of SOME class => SOME (Term.map_type_tvar

          (K (TVar ((Name.aT, 0), [class]))) (Sign.the_const_type thy c))

      | NONE => get_constr_typ thy c);

local

fun get_funcs thy const =

  Symtab.lookup ((the_funcs o the_exec) thy) const

  |> Option.map (Susp.force o snd)

  |> these

  |> (map o apfst) (Thm.transfer thy);

in

fun these_funcs thy const =

  let

    fun drop_refl thy = filter_out (is_equal o Term.fast_term_ord o Logic.dest_equals

      o ObjectLogic.drop_judgment thy o Thm.plain_prop_of o fst);

  in

    get_funcs thy const

    |> burrow_fst (preprocess thy)

    |> drop_refl thy

  end;

fun default_typ thy c = case default_typ_proto thy c

 of SOME ty => Code_Unit.typscheme thy (c, ty)

  | NONE => (case get_funcs thy c

     of (thm, _) :: _ => snd (Code_Unit.head_func (AxClass.unoverload thy thm))

      | [] => Code_Unit.typscheme thy (c, Sign.the_const_type thy c));

end; (*local*)

end; (*struct*)

(** type-safe interfaces for data depedent on executable content **)

functor CodeDataFun(Data: CODE_DATA_ARGS): CODE_DATA =

struct

type T = Data.T;

exception Data of T;

fun dest (Data x) = x

val kind = Code.declare_data (Data Data.empty)

  (fn thy => fn cs => fn Data x => Data (Data.purge thy cs x));

val data_op = (kind, Data, dest);

val get = Code.get_data data_op;

val change = Code.change_data data_op;

fun change_yield thy = Code.change_yield_data data_op thy;

end;

structure Code : CODE = struct open Code; end;