(*  Title:      Pure/Tools/codegen_package.ML

     ID:         $Id$

     Author:     Florian Haftmann, TU Muenchen

 Code generator extraction kernel. Code generator Isar setup.

 *)

 signature CODEGEN_PACKAGE =

 sig

   include BASIC_CODEGEN_THINGOL;

   val codegen_term: theory -> term -> thm * iterm;

   val eval_term: theory -> (string (*reference name!*) * 'a option ref) * term -> 'a;

   val const_of_idf: theory -> string -> string * typ;

   val get_root_module: theory -> CodegenThingol.code;

   type appgen;

   val add_appconst: string * appgen -> theory -> theory;

   val appgen_numeral: (theory -> term -> IntInf.int) -> appgen;

   val appgen_char: (term -> int option) -> appgen;

   val appgen_case: (theory -> term

     -> ((string * typ) list * ((term * typ) * (term * term) list)) option)

     -> appgen;

   val appgen_let: appgen;

 end;

 structure CodegenPackage : CODEGEN_PACKAGE =

 struct

 open BasicCodegenThingol;

 val tracing = CodegenThingol.tracing;

 val succeed = CodegenThingol.succeed;

 val fail = CodegenThingol.fail;

 (** code extraction **)

 (* theory data *)

 structure Code = CodeDataFun

 (struct

   val name = "Pure/code";

   type T = CodegenThingol.code;

   val empty = CodegenThingol.empty_code;

   fun merge _ = CodegenThingol.merge_code;

   fun purge _ NONE _ = CodegenThingol.empty_code

     | purge NONE _ _ = CodegenThingol.empty_code

     | purge (SOME thy) (SOME cs) code =

         let

           val cs_exisiting =

             map_filter (CodegenNames.const_rev thy) (Graph.keys code);

         in

           Graph.del_nodes

             ((Graph.all_succs code

               o map (CodegenNames.const thy)

               o filter (member CodegenConsts.eq_const cs_exisiting)

               ) cs)

             code

         end;

 end);

 type appgen = theory -> ((sort -> sort) * Sorts.algebra) * Consts.T

   -> CodegenFuncgr.T

   -> bool * string list option

   -> (string * typ) * term list -> CodegenThingol.transact -> iterm * CodegenThingol.transact;

 type appgens = (int * (appgen * stamp)) Symtab.table;

 val merge_appgens : appgens * appgens -> appgens =

   Symtab.merge (fn ((bounds1, (_, stamp1)), (bounds2, (_, stamp2))) =>

     bounds1 = bounds2 andalso stamp1 = stamp2);

 structure Consttab = CodegenConsts.Consttab;

 type abstypes = typ Symtab.table * CodegenConsts.const Consttab.table;

 fun merge_abstypes ((typs1, consts1) : abstypes, (typs2, consts2) : abstypes) =

   (Symtab.merge (Type.eq_type Vartab.empty) (typs1, typs2),

     Consttab.merge CodegenConsts.eq_const (consts1, consts2));

 structure CodegenPackageData = TheoryDataFun

 (struct

   val name = "Pure/codegen_package";

   type T = appgens * abstypes;

   val empty = (Symtab.empty, (Symtab.empty, Consttab.empty));

   val copy = I;

   val extend = I;

   fun merge _ ((appgens1, abstypes1), (appgens2, abstypes2)) =

     (merge_appgens (appgens1, appgens2), merge_abstypes (abstypes1, abstypes2));

   fun print _ _ = ();

 end);

 val _ = Context.add_setup (Code.init #> CodegenPackageData.init);

 (* extraction kernel *)

 fun check_strict (false, _) has_seri x =

       false

   | check_strict (_, SOME targets) has_seri x =

       not (has_seri targets x)

   | check_strict (true, _) has_seri x =

       true;

 fun get_abstype thy (tyco, tys) = case Symtab.lookup ((fst o snd o CodegenPackageData.get) thy) tyco

  of SOME ty => SOME ((map_atyps (fn TFree (n, _) => nth tys (the (Int.fromString n)))) ty)

   | NONE => NONE;

 fun ensure_def_class thy (algbr as ((proj_sort, _), _)) funcgr strct class trns =

   let

     val (v, cs) = (ClassPackage.the_consts_sign thy) class;

     val superclasses = (proj_sort o Sign.super_classes thy) class;

     val classops' = map (CodegenNames.const thy o CodegenConsts.norm_of_typ thy) cs;

     val class' = CodegenNames.class thy class;

     fun defgen_class trns =

       trns

       |> fold_map (ensure_def_class thy algbr funcgr strct) superclasses

       ||>> (fold_map (exprgen_type thy algbr funcgr strct) o map snd) cs

       |-> (fn (superclasses, classoptyps) => succeed

         (CodegenThingol.Class (superclasses,

           (unprefix "'" v, classops' ~~ classoptyps))))

   in

     trns

     |> tracing (fn _ => "generating class " ^ quote class)

     |> CodegenThingol.ensure_def defgen_class true

         ("generating class " ^ quote class) class'

     |> pair class'

   end

 and ensure_def_tyco thy algbr funcgr strct tyco trns =

   let

     fun defgen_datatype trns =

       case CodegenData.get_datatype thy tyco

        of SOME (vs, cos) =>

             trns

             |> fold_map (exprgen_tyvar_sort thy algbr funcgr strct) vs

             ||>> fold_map (fn (c, tys) =>

               fold_map (exprgen_type thy algbr funcgr strct) tys

               #-> (fn tys' =>

                 pair ((CodegenNames.const thy o CodegenConsts.norm_of_typ thy)

                   (c, tys ---> Type (tyco, map TFree vs)), tys'))) cos

             |-> (fn (vs, cos) => succeed (CodegenThingol.Datatype (vs, cos)))

         | NONE =>

             trns

             |> fail ("No such datatype: " ^ quote tyco)

     val tyco' = CodegenNames.tyco thy tyco;

     val strict = check_strict strct (CodegenSerializer.tyco_has_serialization thy) tyco';

   in

     trns

     |> tracing (fn _ => "generating type constructor " ^ quote tyco)

     |> CodegenThingol.ensure_def defgen_datatype strict

         ("generating type constructor " ^ quote tyco) tyco'

     |> pair tyco'

   end

 and exprgen_tyvar_sort thy (algbr as ((proj_sort, _), _)) funcgr strct (v, sort) trns =

   trns

   |> fold_map (ensure_def_class thy algbr funcgr strct) (proj_sort sort)

   |-> (fn sort => pair (unprefix "'" v, sort))

 and exprgen_type thy algbr funcgr strct (TVar _) trns =

       error "TVar encountered in typ during code generation"

   | exprgen_type thy algbr funcgr strct (TFree vs) trns =

       trns

       |> exprgen_tyvar_sort thy algbr funcgr strct vs

       |-> (fn (v, sort) => pair (ITyVar v))

   | exprgen_type thy algbr funcgr strct (Type ("fun", [t1, t2])) trns =

       trns

       |> exprgen_type thy algbr funcgr strct t1

       ||>> exprgen_type thy algbr funcgr strct t2

       |-> (fn (t1', t2') => pair (t1' `-> t2'))

   | exprgen_type thy algbr funcgr strct (Type (tyco, tys)) trns =

       case get_abstype thy (tyco, tys)

        of SOME ty =>

             trns

             |> exprgen_type thy algbr funcgr strct ty

         | NONE =>

             trns

             |> ensure_def_tyco thy algbr funcgr strct tyco

             ||>> fold_map (exprgen_type thy algbr funcgr strct) tys

             |-> (fn (tyco, tys) => pair (tyco `%% tys));

 exception CONSTRAIN of (string * typ) * typ;

 fun exprgen_typinst thy (algbr as ((proj_sort, algebra), consts)) funcgr strct (ty_ctxt, sort_decl) trns =

   let

     val pp = Sign.pp thy;

     datatype inst =

         Inst of (class * string) * inst list list

       | Contxt of (string * sort) * (class list * int);

     fun classrel (l as Contxt (v_sort, (classes, n)), _) class  =

           Contxt (v_sort, (class :: classes, n))

       | classrel (Inst ((_, tyco), lss), _) class =

           Inst ((class, tyco), lss);

     fun constructor tyco iss class =

       Inst ((class, tyco), (map o map) fst iss);

     fun variable (TFree (v, sort)) =

       let

         val sort' = proj_sort sort;

       in map_index (fn (n, class) => (Contxt ((v, sort'), ([], n)), class)) sort' end;

     val insts = Sorts.of_sort_derivation pp algebra

       {classrel = classrel, constructor = constructor, variable = variable}

       (ty_ctxt, proj_sort sort_decl);

     fun mk_dict (Inst (inst, instss)) trns =

           trns

           |> ensure_def_inst thy algbr funcgr strct inst

           ||>> (fold_map o fold_map) mk_dict instss

           |-> (fn (inst, instss) => pair (Instance (inst, instss)))

       | mk_dict (Contxt ((v, sort), (classes, k))) trns =

           trns

           |> fold_map (ensure_def_class thy algbr funcgr strct) classes

           |-> (fn classes => pair (Context (classes, (unprefix "'" v,

                 if length sort = 1 then ~1 else k))))

   in

     trns

     |> fold_map mk_dict insts

   end

 and exprgen_typinst_const thy (algbr as (_, consts)) funcgr strct (c, ty_ctxt) trns =

   let

     val c' = CodegenConsts.norm_of_typ thy (c, ty_ctxt)

     val idf = CodegenNames.const thy c';

     val ty_decl = Consts.declaration consts idf;

     val insts = (op ~~ o apsnd (map (snd o dest_TVar)) oo pairself)

       (curry (Consts.typargs consts) idf) (ty_ctxt, ty_decl);

     val _ = if exists not (map (Sign.of_sort thy) insts)

       then raise CONSTRAIN ((c, ty_decl), ty_ctxt) else ();

   in

     trns

     |> fold_map (exprgen_typinst thy algbr funcgr strct) insts

   end

 and ensure_def_inst thy (algbr as ((proj_sort, _), _)) funcgr strct (class, tyco) trns =

   let

     val (vs, classop_defs) = ((apsnd o map) Const o ClassPackage.the_inst_sign thy)

       (class, tyco);

     val classops = (map (CodegenConsts.norm_of_typ thy) o snd

       o ClassPackage.the_consts_sign thy) class;

     val arity_typ = Type (tyco, (map TFree vs));

     val superclasses = (proj_sort o Sign.super_classes thy) class

     fun gen_superarity superclass trns =

       trns

       |> ensure_def_class thy algbr funcgr strct superclass

       ||>> exprgen_typinst thy algbr funcgr strct (arity_typ, [superclass])

       |-> (fn (superclass, [Instance (inst, iss)]) => pair (superclass, (inst, iss)));

     fun gen_classop_def (classop, t) trns =

       trns

       |> ensure_def_const thy algbr funcgr strct classop

       ||>> exprgen_term thy algbr funcgr strct t;

     fun defgen_inst trns =

       trns

       |> ensure_def_class thy algbr funcgr strct class

       ||>> ensure_def_tyco thy algbr funcgr strct tyco

       ||>> fold_map (exprgen_tyvar_sort thy algbr funcgr strct) vs

       ||>> fold_map gen_superarity superclasses

       ||>> fold_map gen_classop_def (classops ~~ classop_defs)

       |-> (fn ((((class, tyco), arity), superarities), classops) =>

              succeed (CodegenThingol.Classinst ((class, (tyco, arity)), (superarities, classops))));

     val inst = CodegenNames.instance thy (class, tyco);

   in

     trns

     |> tracing (fn _ => "generating instance " ^ quote class ^ " / " ^ quote tyco)

     |> CodegenThingol.ensure_def defgen_inst true

          ("generating instance " ^ quote class ^ " / " ^ quote tyco) inst

     |> pair inst

   end

 and ensure_def_const thy (algbr as (_, consts)) funcgr strct (c, tys) trns =

   let

     val c' = CodegenNames.const thy (c, tys);

     fun defgen_datatypecons trns =

       trns

       |> ensure_def_tyco thy algbr funcgr strct

           ((the o CodegenData.get_datatype_of_constr thy) (c, tys))

       |-> (fn _ => succeed CodegenThingol.Bot);

     fun defgen_classop trns =

       trns

       |> ensure_def_class thy algbr funcgr strct ((the o AxClass.class_of_param thy) c)

       |-> (fn _ => succeed CodegenThingol.Bot);

     fun defgen_fun trns =

       case CodegenFuncgr.get_funcs funcgr

         (perhaps (Consttab.lookup ((snd o snd o CodegenPackageData.get) thy)) (c, tys))

        of eq_thms as eq_thm :: _ =>

             let

               val msg = cat_lines ("generating code for theorems " :: map string_of_thm eq_thms);

               val ty = (Logic.unvarifyT o CodegenData.typ_func thy) eq_thm;

               val vs = (map dest_TFree o Consts.typargs consts) (c', ty);

               val dest_eqthm =

                 apfst (snd o strip_comb) o Logic.dest_equals o Logic.unvarify o prop_of;

               fun exprgen_eq (args, rhs) trns =

                 trns

                 |> fold_map (exprgen_term thy algbr funcgr strct) args

                 ||>> exprgen_term thy algbr funcgr strct rhs;

             in

               trns

               |> CodegenThingol.message msg (fn trns => trns

               |> fold_map (exprgen_eq o dest_eqthm) eq_thms

               ||>> fold_map (exprgen_tyvar_sort thy algbr funcgr strct) vs

               ||>> exprgen_type thy algbr funcgr strct ty

               |-> (fn ((eqs, vs), ty) => succeed (CodegenThingol.Fun (eqs, (vs, ty)))))

             end

         | [] =>

               trns

               |> fail ("No defining equations found for "

                    ^ (quote o CodegenConsts.string_of_const thy) (c, tys));

     val defgen =

       if CodegenNames.has_nsp CodegenNames.nsp_fun c'

       then defgen_fun

       else if CodegenNames.has_nsp CodegenNames.nsp_classop c'

       then defgen_classop

       else if CodegenNames.has_nsp CodegenNames.nsp_dtco c'

       then defgen_datatypecons

       else error ("Illegal shallow name space for constant: " ^ quote c');

     val strict = check_strict strct (CodegenSerializer.const_has_serialization thy) c';

   in

     trns

     |> tracing (fn _ => "generating constant "

         ^ (quote o CodegenConsts.string_of_const thy) (c, tys))

     |> CodegenThingol.ensure_def defgen strict ("generating constant "

          ^ CodegenConsts.string_of_const thy (c, tys)) c'

     |> pair c'

   end

 and exprgen_term thy algbr funcgr strct (Const (c, ty)) trns =

       trns

       |> select_appgen thy algbr funcgr strct ((c, ty), [])

   | exprgen_term thy algbr funcgr strct (Var _) trns =

       error "Var encountered in term during code generation"

   | exprgen_term thy algbr funcgr strct (Free (v, ty)) trns =

       trns

       |> exprgen_type thy algbr funcgr strct ty

       |-> (fn _ => pair (IVar v))

   | exprgen_term thy algbr funcgr strct (Abs (raw_v, ty, raw_t)) trns =

       let

         val (v, t) = Syntax.variant_abs (CodegenNames.purify_var raw_v, ty, raw_t);

       in

         trns

         |> exprgen_type thy algbr funcgr strct ty

         ||>> exprgen_term thy algbr funcgr strct t

         |-> (fn (ty, t) => pair ((v, ty) `|-> t))

       end

   | exprgen_term thy algbr funcgr strct (t as _ $ _) trns =

       case strip_comb t

        of (Const (c, ty), ts) =>

             trns

             |> select_appgen thy algbr funcgr strct ((c, ty), ts)

             |-> (fn t => pair t)

         | (t', ts) =>

             trns

             |> exprgen_term thy algbr funcgr strct t'

             ||>> fold_map (exprgen_term thy algbr funcgr strct) ts

             |-> (fn (t, ts) => pair (t `$$ ts))

 and appgen_default thy algbr funcgr strct ((c, ty), ts) trns =

   trns

   |> ensure_def_const thy algbr funcgr strct (CodegenConsts.norm_of_typ thy (c, ty))

   ||>> exprgen_type thy algbr funcgr strct ty

   ||>> exprgen_typinst_const thy algbr funcgr strct (c, ty)

   ||>> fold_map (exprgen_term thy algbr funcgr strct) ts

   |-> (fn (((c, ty), iss), ts) =>

          pair (IConst (c, (iss, ty)) `$$ ts))

 and select_appgen thy algbr funcgr strct ((c, ty), ts) trns =

   case Symtab.lookup (fst (CodegenPackageData.get thy)) c

    of SOME (i, (appgen, _)) =>

         if length ts < i then

           let

             val tys = Library.take (i - length ts, ((fst o strip_type) ty));

             val vs = Name.names (Name.declare c Name.context) "a" tys;

           in

             trns

             |> fold_map (exprgen_type thy algbr funcgr strct) tys

             ||>> appgen thy algbr funcgr strct ((c, ty), ts @ map Free vs)

             |-> (fn (tys, t) => pair (map2 (fn (v, _) => pair v) vs tys `|--> t))

           end

         else if length ts > i then

           trns

           |> appgen thy algbr funcgr strct ((c, ty), Library.take (i, ts))

           ||>> fold_map (exprgen_term thy algbr funcgr strct) (Library.drop (i, ts))

           |-> (fn (t, ts) => pair (t `$$ ts))

         else

           trns

           |> appgen thy algbr funcgr strct ((c, ty), ts)

     | NONE =>

         trns

         |> appgen_default thy algbr funcgr strct ((c, ty), ts);

 (* entrance points into extraction kernel *)

 fun ensure_def_const' thy algbr funcgr strct c trns =

   ensure_def_const thy algbr funcgr strct c trns

   handle CONSTRAIN ((c, ty), ty_decl) => error (

     "Constant " ^ c ^ " with most general type\n"

     ^ Sign.string_of_typ thy ty

     ^ "\noccurs with type\n"

     ^ Sign.string_of_typ thy ty_decl);

 fun exprgen_term' thy algbr funcgr strct t trns =

   exprgen_term thy algbr funcgr strct t trns

   handle CONSTRAIN ((c, ty), ty_decl) => error ("In term " ^ (quote o Sign.string_of_term thy) t

     ^ ",\nconstant " ^ c ^ " with most general type\n"

     ^ Sign.string_of_typ thy ty

     ^ "\noccurs with type\n"

     ^ Sign.string_of_typ thy ty_decl);

 (* parametrized application generators, for instantiation in object logic *)

 (* (axiomatic extensions of extraction kernel *)

 fun appgen_numeral int_of_numeral thy algbr funcgr strct (app as (c, ts)) trns =

   case try (int_of_numeral thy) (list_comb (Const c, ts))

    of SOME i =>

         trns

         |> appgen_default thy algbr funcgr strct app

         |-> (fn t => pair (CodegenThingol.INum (i, t)))

     | NONE =>

         trns

         |> appgen_default thy algbr funcgr strct app;

 fun appgen_char char_to_index thy algbr funcgr strct (app as ((_, ty), _)) trns =

   case (char_to_index o list_comb o apfst Const) app

    of SOME i =>

         trns

         |> exprgen_type thy algbr funcgr strct ty

         ||>> appgen_default thy algbr funcgr strct app

         |-> (fn (_, t0) => pair (IChar (chr i, t0)))

     | NONE =>

         trns

         |> appgen_default thy algbr funcgr strct app;

 fun appgen_case dest_case_expr thy algbr funcgr strct (app as (c_ty, ts)) trns =

   let

     val SOME ([], ((st, sty), ds)) = dest_case_expr thy (list_comb (Const c_ty, ts));

     fun clausegen (dt, bt) trns =

       trns

       |> exprgen_term thy algbr funcgr strct dt

       ||>> exprgen_term thy algbr funcgr strct bt;

   in

     trns

     |> exprgen_term thy algbr funcgr strct st

     ||>> exprgen_type thy algbr funcgr strct sty

     ||>> fold_map clausegen ds

     ||>> appgen_default thy algbr funcgr strct app

     |-> (fn (((se, sty), ds), e0) => pair (ICase (((se, sty), ds), e0)))

   end;

 fun appgen_let thy algbr funcgr strct (app as (_, [st, ct])) trns =

   trns

   |> exprgen_term thy algbr funcgr strct ct

   ||>> exprgen_term thy algbr funcgr strct st

   ||>> appgen_default thy algbr funcgr strct app

   |-> (fn (((v, ty) `|-> be, se), e0) =>

             pair (ICase (((se, ty), case be

               of ICase (((IVar w, _), ds), _) => if v = w then ds else [(IVar v, be)]

                | _ => [(IVar v, be)]

             ), e0))

         | (_, e0) => pair e0);

 fun add_appconst (c, appgen) thy =

   let

     val i = (length o fst o strip_type o Sign.the_const_type thy) c;

     val _ = Code.change thy (K CodegenThingol.empty_code);

   in

     (CodegenPackageData.map o apfst)

       (Symtab.update (c, (i, (appgen, stamp ())))) thy

   end;

 (** abstype and constsubst interface **)

 fun gen_abstyp prep_const prep_typ (raw_abstyp, raw_substtyp) raw_absconsts thy =

   let

     val abstyp = Type.no_tvars (prep_typ thy raw_abstyp);

     val substtyp = Type.no_tvars (prep_typ thy raw_substtyp);

     val absconsts = (map o pairself) (prep_const thy) raw_absconsts;

     val Type (abstyco, tys) = abstyp handle BIND => error ("bad type: " ^ Sign.string_of_typ thy abstyp);

     val typarms = map (fst o dest_TFree) tys handle MATCH => error ("bad type: " ^ Sign.string_of_typ thy abstyp);

     fun mk_index v = 

       let

         val k = find_index (fn w => v = w) typarms;

       in if k = ~1

         then error ("free type variable: " ^ quote v)

         else TFree (string_of_int k, [])

       end;

     val typpat = map_atyps (fn TFree (v, _) => mk_index v) substtyp;

     fun apply_typpat (Type (tyco, tys)) =

           let

             val tys' = map apply_typpat tys;

           in if tyco = abstyco then

             (map_atyps (fn TFree (n, _) => nth tys' (the (Int.fromString n)))) typpat

           else

             Type (tyco, tys')

           end

       | apply_typpat ty = ty;

     val string_of_typ = setmp show_sorts true (Sign.string_of_typ thy);

     fun add_consts (c1, c2) =

       let

         val _ = if CodegenNames.has_nsp CodegenNames.nsp_fun (CodegenNames.const thy c2)

           then ()

           else error ("not a function: " ^ CodegenConsts.string_of_const thy c2);

         val funcgr = CodegenFuncgr.mk_funcgr thy [c1, c2] [];

         val ty_map = CodegenFuncgr.get_func_typs funcgr;

         val ty1 = (apply_typpat o the o AList.lookup CodegenConsts.eq_const ty_map) c1;

         val ty2 = (the o AList.lookup CodegenConsts.eq_const ty_map) c2;

         val _ = if Sign.typ_equiv thy (ty1, ty2) then () else

           error ("Incompatiable type signatures of " ^ CodegenConsts.string_of_const thy c1

             ^ " and " ^ CodegenConsts.string_of_const thy c2 ^ ":\n"

             ^ string_of_typ ty1 ^ "\n" ^ string_of_typ ty2);

       in Consttab.update (c1, c2) end;

     val _ = Code.change thy (K CodegenThingol.empty_code);

   in

     thy

     |> (CodegenPackageData.map o apsnd) (fn (abstypes, abscs) =>

           (abstypes

           |> Symtab.update (abstyco, typpat),

           abscs

           |> fold add_consts absconsts)

        )

   end;

 fun gen_constsubst prep_const raw_constsubsts thy =

   let

     val constsubsts = (map o pairself) (prep_const thy) raw_constsubsts;

     val string_of_typ = setmp show_sorts true (Sign.string_of_typ thy);

     fun add_consts (c1, c2) =

       let

         val _ = if CodegenNames.has_nsp CodegenNames.nsp_fun (CodegenNames.const thy c2)

           then ()

           else error ("not a function: " ^ CodegenConsts.string_of_const thy c2);

         val funcgr = CodegenFuncgr.mk_funcgr thy [c1, c2] [];

         val ty_map = CodegenFuncgr.get_func_typs funcgr;

         val ty1 = (the o AList.lookup CodegenConsts.eq_const ty_map) c1;

         val ty2 = (the o AList.lookup CodegenConsts.eq_const ty_map) c2;

         val _ = if Sign.typ_equiv thy (ty1, ty2) then () else

           error ("Incompatiable type signatures of " ^ CodegenConsts.string_of_const thy c1

             ^ " and " ^ CodegenConsts.string_of_const thy c2 ^ ":\n"

             ^ string_of_typ ty1 ^ "\n" ^ string_of_typ ty2);

       in Consttab.update (c1, c2) end;

     val _ = Code.change thy (K CodegenThingol.empty_code);

   in

     thy

     |> (CodegenPackageData.map o apsnd o apsnd) (fold add_consts constsubsts)

   end;

 val abstyp = gen_abstyp CodegenConsts.norm Sign.certify_typ;

 val abstyp_e = gen_abstyp CodegenConsts.read_const (fn thy => Sign.read_typ (thy, K NONE));

 val constsubst = gen_constsubst CodegenConsts.norm;

 val constsubst_e = gen_constsubst CodegenConsts.read_const;

 (** code generation interfaces **)

 fun generate thy (cs, rhss) targets init gen it =

   let

     val raw_funcgr = CodegenFuncgr.mk_funcgr thy cs rhss;

     val cs' = map_filter (Consttab.lookup ((snd o snd o CodegenPackageData.get) thy))

       (CodegenFuncgr.Constgraph.keys raw_funcgr);

     val funcgr = CodegenFuncgr.mk_funcgr thy cs' [];

     val qnaming = NameSpace.qualified_names NameSpace.default_naming;

     val algebr = ClassPackage.operational_algebra thy;

     val consttab = Consts.empty

       |> fold (fn (c, ty) => Consts.declare qnaming

            ((CodegenNames.const thy c, ty), true))

            (CodegenFuncgr.get_func_typs funcgr);

     val algbr = (algebr, consttab);

   in   

     Code.change_yield thy (CodegenThingol.start_transact init (gen thy algbr funcgr

         (true, targets) it))

     |> (fn (x, modl) => x)

   end;

 fun codegen_term thy t =

   let

     fun const_typ (c, ty) =

       let

         val const = CodegenConsts.norm_of_typ thy (c, ty);

         val funcgr = CodegenFuncgr.mk_funcgr thy [const] [];

       in case CodegenFuncgr.get_funcs funcgr const

        of (thm :: _) => CodegenData.typ_func thy thm

         | [] => Sign.the_const_type thy c

       end;

     val ct = Thm.cterm_of thy t;

     val (thm, ct') = CodegenData.preprocess_cterm thy

       (const_typ) ct;

     val t' = Thm.term_of ct';

     val cs_rhss = CodegenConsts.consts_of thy t';

   in

     (thm, generate thy cs_rhss (SOME []) NONE exprgen_term' t')

   end;

 fun const_of_idf thy =

   CodegenConsts.typ_of_inst thy o the o CodegenNames.const_rev thy;

 fun get_root_module thy =

   Code.get thy;

 fun eval_term thy (ref_spec, t) =

   let

     val _ = Term.fold_atyps (fn _ =>

       error ("Term" ^ Sign.string_of_term thy t ^ "is polymorhpic"))

       (Term.fastype_of t);

     val (_, t') = codegen_term thy t;

   in

     CodegenSerializer.eval_term thy (ref_spec, t') (Code.get thy)

   end;

 (** toplevel interface and setup **)

 local

 structure P = OuterParse

 and K = OuterKeyword

 fun code raw_cs seris thy =

   let

     val cs = map (CodegenConsts.read_const thy) raw_cs;

     val targets = case map fst seris

      of [] => NONE

       | xs => SOME xs;

     val seris' = map_filter (fn (target, args as _ :: _) =>

       SOME (CodegenSerializer.get_serializer thy (target, args)) | _ => NONE) seris;

     fun generate' thy = case cs

      of [] => []

       | _ =>

           generate thy (cs, []) targets NONE (fold_map oooo ensure_def_const') cs;

     fun serialize' [] code seri =

           seri NONE code 

       | serialize' cs code seri =

           seri (SOME cs) code;

     val cs = generate' thy;

     val code = Code.get thy;

   in

     (map (serialize' cs code) seris'; ())

   end;

 val (codeK, code_abstypeK, code_constsubstK) =

   ("code_gen", "code_abstype", "code_constsubst");

 in

 val codeP =

   OuterSyntax.improper_command codeK "generate and serialize executable code for constants" K.diag (

     Scan.repeat P.term

     -- Scan.repeat (P.$$$ "(" |--

         P.name -- P.arguments

         --| P.$$$ ")")

     >> (fn (raw_cs, seris) => Toplevel.keep (code raw_cs seris o Toplevel.theory_of))

   );

 val code_abstypeP =

   OuterSyntax.command code_abstypeK "axiomatic abstypes for code generation" K.thy_decl (

     (P.typ -- P.typ -- Scan.optional (P.$$$ "where" |-- Scan.repeat1

         (P.term --| (P.$$$ "\\<equiv>" || P.$$$ "==") -- P.term)) [])

     >> (Toplevel.theory o uncurry abstyp_e)

   );

 val code_constsubstP =

   OuterSyntax.command code_constsubstK "axiomatic constant substitutions for code generation" K.thy_decl (

     Scan.repeat1 (P.term --| (P.$$$ "\\<equiv>" || P.$$$ "==") -- P.term)

     >> (Toplevel.theory o constsubst_e)

   );

 val _ = OuterSyntax.add_parsers [codeP, code_abstypeP, code_constsubstP];

 end; (* local *)

 end; (* struct *)