src/Tools/nbe.ML
author haftmann
Fri Nov 26 23:13:58 2010 +0100 (2010-11-26)
changeset 40730 2aa0390a2da7
parent 40564 6827505e96e1
child 41037 6d6f23b3a879
permissions -rw-r--r--
nbe decides equality of abstractions by extensionality
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(*  Title:      Tools/nbe.ML
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    Authors:    Klaus Aehlig, LMU Muenchen; Tobias Nipkow, Florian Haftmann, TU Muenchen
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Normalization by evaluation, based on generic code generator.
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*)
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signature NBE =
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sig
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  val dynamic_eval_conv: conv
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  val dynamic_eval_value: theory -> term -> term
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  val static_eval_conv: theory -> string list -> conv
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  datatype Univ =
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      Const of int * Univ list               (*named (uninterpreted) constants*)
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    | DFree of string * int                  (*free (uninterpreted) dictionary parameters*)
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    | BVar of int * Univ list
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    | Abs of (int * (Univ list -> Univ)) * Univ list
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  val apps: Univ -> Univ list -> Univ        (*explicit applications*)
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  val abss: int -> (Univ list -> Univ) -> Univ
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                                             (*abstractions as closures*)
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  val eq_Univ: Univ * Univ -> bool
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  val put_result: (unit -> Univ list -> Univ list) -> Proof.context -> Proof.context
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  val trace: bool Unsynchronized.ref
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  val setup: theory -> theory
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  val add_const_alias: thm -> theory -> theory
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end;
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structure Nbe: NBE =
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struct
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(* generic non-sense *)
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val trace = Unsynchronized.ref false;
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fun traced f x = if !trace then (tracing (f x); x) else x;
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(** certificates and oracle for "trivial type classes" **)
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structure Triv_Class_Data = Theory_Data
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(
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  type T = (class * thm) list;
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  val empty = [];
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  val extend = I;
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  fun merge data : T = AList.merge (op =) (K true) data;
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);
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fun add_const_alias thm thy =
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  let
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    val (ofclass, eqn) = case try Logic.dest_equals (Thm.prop_of thm)
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     of SOME ofclass_eq => ofclass_eq
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      | _ => error ("Bad certificate: " ^ Display.string_of_thm_global thy thm);
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    val (T, class) = case try Logic.dest_of_class ofclass
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     of SOME T_class => T_class
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      | _ => error ("Bad certificate: " ^ Display.string_of_thm_global thy thm);
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    val tvar = case try Term.dest_TVar T
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     of SOME (tvar as (_, sort)) => if null (filter (can (AxClass.get_info thy)) sort)
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          then tvar
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          else error ("Bad sort: " ^ Display.string_of_thm_global thy thm)
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      | _ => error ("Bad type: " ^ Display.string_of_thm_global thy thm);
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    val _ = if Term.add_tvars eqn [] = [tvar] then ()
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      else error ("Inconsistent type: " ^ Display.string_of_thm_global thy thm);
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    val lhs_rhs = case try Logic.dest_equals eqn
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     of SOME lhs_rhs => lhs_rhs
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      | _ => error ("Not an equation: " ^ Syntax.string_of_term_global thy eqn);
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    val c_c' = case try (pairself (AxClass.unoverload_const thy o dest_Const)) lhs_rhs
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     of SOME c_c' => c_c'
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      | _ => error ("Not an equation with two constants: "
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          ^ Syntax.string_of_term_global thy eqn);
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    val _ = if the_list (AxClass.class_of_param thy (snd c_c')) = [class] then ()
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      else error ("Inconsistent class: " ^ Display.string_of_thm_global thy thm);
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  in Triv_Class_Data.map (AList.update (op =) (class, thm)) thy end;
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local
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val get_triv_classes = map fst o Triv_Class_Data.get;
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val (_, triv_of_class) = Context.>>> (Context.map_theory_result
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  (Thm.add_oracle (Binding.name "triv_of_class", fn (thy, T, class) =>
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    Thm.cterm_of thy (Logic.mk_of_class (T, class)))));
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in
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fun lift_triv_classes_conv thy conv ct =
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  let
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    val algebra = Sign.classes_of thy;
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    val certT = Thm.ctyp_of thy;
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    val triv_classes = get_triv_classes thy;
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    fun additional_classes sort = filter_out (fn class => Sorts.sort_le algebra (sort, [class])) triv_classes;
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    fun mk_entry (v, sort) =
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      let
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        val T = TFree (v, sort);
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        val cT = certT T;
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        val triv_sort = additional_classes sort;
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      in
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        (v, (Sorts.inter_sort algebra (sort, triv_sort),
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          (cT, AList.make (fn class => Thm.of_class (cT, class)) sort
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            @ AList.make (fn class => triv_of_class (thy, T, class)) triv_sort)))
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      end;
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    val vs_tab = map mk_entry (Term.add_tfrees (Thm.term_of ct) []);
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    fun instantiate thm =
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      let
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        val cert_tvars = map (certT o TVar) (Term.add_tvars
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          ((fst o Logic.dest_equals o Logic.strip_imp_concl o Thm.prop_of) thm) []);
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        val instantiation =
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          map2 (fn cert_tvar => fn (_, (_, (cT, _))) => (cert_tvar, cT)) cert_tvars vs_tab;
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      in Thm.instantiate (instantiation, []) thm end;
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    fun of_class (TFree (v, _), class) =
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          the (AList.lookup (op =) ((snd o snd o the o AList.lookup (op =) vs_tab) v) class)
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      | of_class (T, _) = error ("Bad type " ^ Syntax.string_of_typ_global thy T);
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    fun strip_of_class thm =
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      let
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        val prems_of_class = Thm.prop_of thm
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          |> Logic.strip_imp_prems
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          |> map (Logic.dest_of_class #> of_class);
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      in fold Thm.elim_implies prems_of_class thm end;
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  in
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    ct
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    |> (Drule.cterm_fun o map_types o map_type_tfree)
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        (fn (v, sort) => TFree (v, (fst o the o AList.lookup (op =) vs_tab) v))
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    |> conv
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    |> Thm.strip_shyps
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    |> Thm.varifyT_global
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    |> Thm.unconstrainT
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    |> instantiate
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    |> strip_of_class
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  end;
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fun lift_triv_classes_rew thy rew t =
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  let
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    val algebra = Sign.classes_of thy;
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    val triv_classes = get_triv_classes thy;
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    val vs = Term.add_tfrees t [];
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  in t
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    |> (map_types o map_type_tfree)
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        (fn (v, sort) => TFree (v, Sorts.inter_sort algebra (sort, triv_classes)))
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    |> rew
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    |> (map_types o map_type_tfree)
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        (fn (v, _) => TFree (v, the (AList.lookup (op =) vs v)))
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  end;
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end;
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(** the semantic universe **)
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(*
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   Functions are given by their semantical function value. To avoid
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   trouble with the ML-type system, these functions have the most
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   generic type, that is "Univ list -> Univ". The calling convention is
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   that the arguments come as a list, the last argument first. In
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   other words, a function call that usually would look like
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   f x_1 x_2 ... x_n   or   f(x_1,x_2, ..., x_n)
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   would be in our convention called as
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              f [x_n,..,x_2,x_1]
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   Moreover, to handle functions that are still waiting for some
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   arguments we have additionally a list of arguments collected to far
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   and the number of arguments we're still waiting for.
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*)
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datatype Univ =
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    Const of int * Univ list           (*named (uninterpreted) constants*)
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  | DFree of string * int              (*free (uninterpreted) dictionary parameters*)
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  | BVar of int * Univ list            (*bound variables, named*)
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  | Abs of (int * (Univ list -> Univ)) * Univ list
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                                       (*abstractions as closures*);
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(* constructor functions *)
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fun abss n f = Abs ((n, f), []);
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fun apps (Abs ((n, f), xs)) ys = let val k = n - length ys in
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      case int_ord (k, 0)
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       of EQUAL => f (ys @ xs)
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        | LESS => let val (zs, ws) = chop (~ k) ys in apps (f (ws @ xs)) zs end
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        | GREATER => Abs ((k, f), ys @ xs) (*note: reverse convention also for apps!*)
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      end
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  | apps (Const (name, xs)) ys = Const (name, ys @ xs)
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  | apps (BVar (n, xs)) ys = BVar (n, ys @ xs);
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fun satisfy_abs (abs as ((n, f), xs)) some_k =
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  let
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    val ys = case some_k
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     of NONE => replicate n (BVar (0, []))
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      | SOME k => map_range (fn l => BVar (k + l, [])) n;
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  in (apps (Abs abs) ys, ys) end;
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fun maxidx (Const (_, xs)) = fold maxidx xs
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  | maxidx (DFree _) = I
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  | maxidx (BVar (l, xs)) = fold maxidx xs #> Integer.max (l + 1)
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  | maxidx (Abs abs) = maxidx (fst (satisfy_abs abs NONE));
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fun eq_Univ (Const (k, xs), Const (l, ys)) = k = l andalso eq_list eq_Univ (xs, ys)
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  | eq_Univ (DFree (s, k), DFree (t, l)) = s = t andalso k = l
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  | eq_Univ (BVar (k, xs), BVar (l, ys)) = k = l andalso eq_list eq_Univ (xs, ys)
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  | eq_Univ (x as Abs abs, y) =
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      let
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        val (x, ys) = satisfy_abs abs ((SOME o maxidx x o maxidx y) 0)
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      in eq_Univ (x, apps y ys) end
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  | eq_Univ (x, y as Abs _) = eq_Univ (y, x)
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  | eq_Univ _ = false;
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(** assembling and compiling ML code from terms **)
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(* abstract ML syntax *)
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infix 9 `$` `$$`;
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fun e1 `$` e2 = "(" ^ e1 ^ " " ^ e2 ^ ")";
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fun e `$$` [] = e
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  | e `$$` es = "(" ^ e ^ " " ^ space_implode " " es ^ ")";
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fun ml_abs v e = "(fn " ^ v ^ " => " ^ e ^ ")";
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fun ml_cases t cs =
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  "(case " ^ t ^ " of " ^ space_implode " | " (map (fn (p, t) => p ^ " => " ^ t) cs) ^ ")";
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fun ml_Let d e = "let\n" ^ d ^ " in " ^ e ^ " end";
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fun ml_as v t = "(" ^ v ^ " as " ^ t ^ ")";
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fun ml_and [] = "true"
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  | ml_and [x] = x
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  | ml_and xs = "(" ^ space_implode " andalso " xs ^ ")";
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fun ml_if b x y = "(if " ^ b ^ " then " ^ x ^ " else " ^ y ^ ")";
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fun ml_list es = "[" ^ commas es ^ "]";
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fun ml_fundefs ([(name, [([], e)])]) =
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      "val " ^ name ^ " = " ^ e ^ "\n"
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  | ml_fundefs (eqs :: eqss) =
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      let
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        fun fundef (name, eqs) =
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          let
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            fun eqn (es, e) = name ^ " " ^ space_implode " " es ^ " = " ^ e
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          in space_implode "\n  | " (map eqn eqs) end;
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      in
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        (prefix "fun " o fundef) eqs :: map (prefix "and " o fundef) eqss
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        |> cat_lines
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        |> suffix "\n"
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      end;
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(* nbe specific syntax and sandbox communication *)
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structure Univs = Proof_Data (
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  type T = unit -> Univ list -> Univ list
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  fun init _ () = error "Univs"
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);
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val put_result = Univs.put;
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local
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  val prefix =      "Nbe.";
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  val name_put =    prefix ^ "put_result";
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  val name_ref =    prefix ^ "univs_ref";
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  val name_const =  prefix ^ "Const";
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  val name_abss =   prefix ^ "abss";
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  val name_apps =   prefix ^ "apps";
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  val name_eq =     prefix ^ "eq_Univ";
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in
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val univs_cookie = (Univs.get, put_result, name_put);
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fun nbe_fun 0 "" = "nbe_value"
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  | nbe_fun i c = "c_" ^ translate_string (fn "." => "_" | c => c) c ^ "_" ^ string_of_int i;
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fun nbe_dict v n = "d_" ^ v ^ "_" ^ string_of_int n;
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fun nbe_bound v = "v_" ^ v;
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fun nbe_bound_optional NONE = "_"
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  | nbe_bound_optional (SOME v) = nbe_bound v;
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fun nbe_default v = "w_" ^ v;
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(*note: these three are the "turning spots" where proper argument order is established!*)
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fun nbe_apps t [] = t
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  | nbe_apps t ts = name_apps `$$` [t, ml_list (rev ts)];
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fun nbe_apps_local i c ts = nbe_fun i c `$` ml_list (rev ts);
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fun nbe_apps_constr idx_of c ts =
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  let
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    val c' = if !trace then string_of_int (idx_of c) ^ " (*" ^ c ^ "*)"
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      else string_of_int (idx_of c);
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  in name_const `$` ("(" ^ c' ^ ", " ^ ml_list (rev ts) ^ ")") end;
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fun nbe_abss 0 f = f `$` ml_list []
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  | nbe_abss n f = name_abss `$$` [string_of_int n, f];
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fun nbe_eq (v1, v2) = "(" ^ name_eq ^ " (" ^ nbe_bound v1 ^ ", " ^ nbe_bound v2 ^ "))";
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end;
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open Basic_Code_Thingol;
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(* code generation *)
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fun assemble_eqnss idx_of deps eqnss =
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  let
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    fun prep_eqns (c, (vs, eqns)) =
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      let
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        val dicts = maps (fn (v, sort) => map_index (nbe_dict v o fst) sort) vs;
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        val num_args = length dicts + ((length o fst o hd) eqns);
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      in (c, (num_args, (dicts, eqns))) end;
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    val eqnss' = map prep_eqns eqnss;
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    fun assemble_constapp c dss ts = 
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      let
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        val ts' = (maps o map) assemble_idict dss @ ts;
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      in case AList.lookup (op =) eqnss' c
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       of SOME (num_args, _) => if num_args <= length ts'
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            then let val (ts1, ts2) = chop num_args ts'
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            in nbe_apps (nbe_apps_local 0 c ts1) ts2
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            end else nbe_apps (nbe_abss num_args (nbe_fun 0 c)) ts'
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        | NONE => if member (op =) deps c
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            then nbe_apps (nbe_fun 0 c) ts'
haftmann@28337
   315
            else nbe_apps_constr idx_of c ts'
haftmann@25924
   316
      end
haftmann@25944
   317
    and assemble_idict (DictConst (inst, dss)) =
haftmann@25944
   318
          assemble_constapp inst dss []
haftmann@25944
   319
      | assemble_idict (DictVar (supers, (v, (n, _)))) =
haftmann@25944
   320
          fold_rev (fn super => assemble_constapp super [] o single) supers (nbe_dict v n);
haftmann@25924
   321
haftmann@28350
   322
    fun assemble_iterm constapp =
haftmann@24155
   323
      let
haftmann@28350
   324
        fun of_iterm match_cont t =
haftmann@25944
   325
          let
haftmann@28054
   326
            val (t', ts) = Code_Thingol.unfold_app t
haftmann@28350
   327
          in of_iapp match_cont t' (fold_rev (cons o of_iterm NONE) ts []) end
haftmann@31049
   328
        and of_iapp match_cont (IConst (c, ((_, dss), _))) ts = constapp c dss ts
haftmann@31889
   329
          | of_iapp match_cont (IVar v) ts = nbe_apps (nbe_bound_optional v) ts
haftmann@31724
   330
          | of_iapp match_cont ((v, _) `|=> t) ts =
haftmann@31888
   331
              nbe_apps (nbe_abss 1 (ml_abs (ml_list [nbe_bound_optional v]) (of_iterm NONE t))) ts
haftmann@28350
   332
          | of_iapp match_cont (ICase (((t, _), cs), t0)) ts =
haftmann@28350
   333
              nbe_apps (ml_cases (of_iterm NONE t)
haftmann@28350
   334
                (map (fn (p, t) => (of_iterm NONE p, of_iterm match_cont t)) cs
haftmann@28350
   335
                  @ [("_", case match_cont of SOME s => s | NONE => of_iterm NONE t0)])) ts
haftmann@25944
   336
      in of_iterm end;
haftmann@24155
   337
haftmann@28350
   338
    fun subst_nonlin_vars args =
haftmann@28350
   339
      let
haftmann@28350
   340
        val vs = (fold o Code_Thingol.fold_varnames)
wenzelm@33002
   341
          (fn v => AList.map_default (op =) (v, 0) (Integer.add 1)) args [];
haftmann@28350
   342
        val names = Name.make_context (map fst vs);
haftmann@28350
   343
        fun declare v k ctxt = let val vs = Name.invents ctxt v k
haftmann@28350
   344
          in (vs, fold Name.declare vs ctxt) end;
haftmann@28350
   345
        val (vs_renames, _) = fold_map (fn (v, k) => if k > 1
haftmann@28350
   346
          then declare v (k - 1) #>> (fn vs => (v, vs))
haftmann@28350
   347
          else pair (v, [])) vs names;
haftmann@28350
   348
        val samepairs = maps (fn (v, vs) => map (pair v) vs) vs_renames;
haftmann@28350
   349
        fun subst_vars (t as IConst _) samepairs = (t, samepairs)
haftmann@31889
   350
          | subst_vars (t as IVar NONE) samepairs = (t, samepairs)
haftmann@31889
   351
          | subst_vars (t as IVar (SOME v)) samepairs = (case AList.lookup (op =) samepairs v
haftmann@31889
   352
             of SOME v' => (IVar (SOME v'), AList.delete (op =) v samepairs)
haftmann@28350
   353
              | NONE => (t, samepairs))
haftmann@28350
   354
          | subst_vars (t1 `$ t2) samepairs = samepairs
haftmann@28350
   355
              |> subst_vars t1
haftmann@28350
   356
              ||>> subst_vars t2
haftmann@28350
   357
              |>> (op `$)
haftmann@28350
   358
          | subst_vars (ICase (_, t)) samepairs = subst_vars t samepairs;
haftmann@28350
   359
        val (args', _) = fold_map subst_vars args samepairs;
haftmann@28350
   360
      in (samepairs, args') end;
haftmann@28350
   361
haftmann@28337
   362
    fun assemble_eqn c dicts default_args (i, (args, rhs)) =
haftmann@28337
   363
      let
haftmann@28337
   364
        val is_eval = (c = "");
haftmann@28337
   365
        val default_rhs = nbe_apps_local (i+1) c (dicts @ default_args);
haftmann@28337
   366
        val match_cont = if is_eval then NONE else SOME default_rhs;
haftmann@28350
   367
        val assemble_arg = assemble_iterm
haftmann@28350
   368
          (fn c => fn _ => fn ts => nbe_apps_constr idx_of c ts) NONE;
haftmann@35371
   369
        val assemble_rhs = assemble_iterm assemble_constapp match_cont;
haftmann@28350
   370
        val (samepairs, args') = subst_nonlin_vars args;
haftmann@28350
   371
        val s_args = map assemble_arg args';
haftmann@28350
   372
        val s_rhs = if null samepairs then assemble_rhs rhs
haftmann@40730
   373
          else ml_if (ml_and (map nbe_eq samepairs))
haftmann@28350
   374
            (assemble_rhs rhs) default_rhs;
haftmann@28337
   375
        val eqns = if is_eval then
haftmann@28350
   376
            [([ml_list (rev (dicts @ s_args))], s_rhs)]
haftmann@28337
   377
          else
haftmann@28350
   378
            [([ml_list (rev (dicts @ map2 ml_as default_args s_args))], s_rhs),
haftmann@28337
   379
              ([ml_list (rev (dicts @ default_args))], default_rhs)]
haftmann@28337
   380
      in (nbe_fun i c, eqns) end;
haftmann@28337
   381
haftmann@25944
   382
    fun assemble_eqns (c, (num_args, (dicts, eqns))) =
haftmann@25944
   383
      let
haftmann@28337
   384
        val default_args = map nbe_default
haftmann@28337
   385
          (Name.invent_list [] "a" (num_args - length dicts));
haftmann@28337
   386
        val eqns' = map_index (assemble_eqn c dicts default_args) eqns
haftmann@28337
   387
          @ (if c = "" then [] else [(nbe_fun (length eqns) c,
haftmann@28337
   388
            [([ml_list (rev (dicts @ default_args))],
haftmann@28337
   389
              nbe_apps_constr idx_of c (dicts @ default_args))])]);
haftmann@28337
   390
      in (eqns', nbe_abss num_args (nbe_fun 0 c)) end;
haftmann@24155
   391
haftmann@25944
   392
    val (fun_vars, fun_vals) = map_split assemble_eqns eqnss';
haftmann@28337
   393
    val deps_vars = ml_list (map (nbe_fun 0) deps);
haftmann@28337
   394
  in ml_abs deps_vars (ml_Let (ml_fundefs (flat fun_vars)) (ml_list fun_vals)) end;
haftmann@25944
   395
haftmann@35371
   396
haftmann@39392
   397
(* compile equations *)
haftmann@25944
   398
haftmann@39392
   399
fun compile_eqnss thy nbe_program raw_deps [] = []
haftmann@39392
   400
  | compile_eqnss thy nbe_program raw_deps eqnss =
haftmann@24155
   401
      let
haftmann@39392
   402
        val ctxt = ProofContext.init_global thy;
haftmann@26064
   403
        val (deps, deps_vals) = split_list (map_filter
haftmann@39392
   404
          (fn dep => Option.map (fn univ => (dep, univ)) (fst ((Graph.get_node nbe_program dep)))) raw_deps);
haftmann@26064
   405
        val idx_of = raw_deps
haftmann@39392
   406
          |> map (fn dep => (dep, snd (Graph.get_node nbe_program dep)))
haftmann@26064
   407
          |> AList.lookup (op =)
haftmann@26064
   408
          |> (fn f => the o f);
haftmann@26064
   409
        val s = assemble_eqnss idx_of deps eqnss;
haftmann@24155
   410
        val cs = map fst eqnss;
haftmann@25944
   411
      in
haftmann@25944
   412
        s
haftmann@32544
   413
        |> traced (fn s => "\n--- code to be evaluated:\n" ^ s)
haftmann@38931
   414
        |> pair ""
haftmann@39911
   415
        |> Code_Runtime.value ctxt univs_cookie
haftmann@25944
   416
        |> (fn f => f deps_vals)
haftmann@25944
   417
        |> (fn univs => cs ~~ univs)
haftmann@25944
   418
      end;
haftmann@25190
   419
wenzelm@30672
   420
haftmann@39392
   421
(* extract equations from statements *)
haftmann@24155
   422
haftmann@37437
   423
fun eqns_of_stmt (_, Code_Thingol.Fun (_, ((_, []), _))) =
haftmann@25101
   424
      []
haftmann@37437
   425
  | eqns_of_stmt (const, Code_Thingol.Fun (_, (((vs, _), eqns), _))) =
haftmann@25101
   426
      [(const, (vs, map fst eqns))]
haftmann@28054
   427
  | eqns_of_stmt (_, Code_Thingol.Datatypecons _) =
haftmann@25101
   428
      []
haftmann@28054
   429
  | eqns_of_stmt (_, Code_Thingol.Datatype _) =
haftmann@25101
   430
      []
haftmann@37447
   431
  | eqns_of_stmt (class, Code_Thingol.Class (_, (v, (super_classes, classparams)))) =
haftmann@25101
   432
      let
haftmann@37384
   433
        val names = map snd super_classes @ map fst classparams;
haftmann@25101
   434
        val params = Name.invent_list [] "d" (length names);
haftmann@25101
   435
        fun mk (k, name) =
haftmann@25101
   436
          (name, ([(v, [])],
haftmann@31889
   437
            [([IConst (class, (([], []), [])) `$$ map (IVar o SOME) params],
haftmann@31889
   438
              IVar (SOME (nth params k)))]));
haftmann@25101
   439
      in map_index mk names end
haftmann@28054
   440
  | eqns_of_stmt (_, Code_Thingol.Classrel _) =
haftmann@25101
   441
      []
haftmann@28054
   442
  | eqns_of_stmt (_, Code_Thingol.Classparam _) =
haftmann@25101
   443
      []
haftmann@37449
   444
  | eqns_of_stmt (inst, Code_Thingol.Classinst ((class, (_, arity_args)), (super_instances, (classparam_instances, _)))) =
haftmann@37384
   445
      [(inst, (arity_args, [([], IConst (class, (([], []), [])) `$$
haftmann@37384
   446
        map (fn (_, (_, (inst, dss))) => IConst (inst, (([], dss), []))) super_instances
haftmann@37384
   447
        @ map (IConst o snd o fst) classparam_instances)]))];
haftmann@24155
   448
haftmann@39392
   449
haftmann@39392
   450
(* compile whole programs *)
haftmann@39392
   451
haftmann@39399
   452
fun ensure_const_idx name (nbe_program, (maxidx, idx_tab)) =
haftmann@39399
   453
  if can (Graph.get_node nbe_program) name
haftmann@39399
   454
  then (nbe_program, (maxidx, idx_tab))
haftmann@39399
   455
  else (Graph.new_node (name, (NONE, maxidx)) nbe_program,
haftmann@39399
   456
    (maxidx + 1, Inttab.update_new (maxidx, name) idx_tab));
haftmann@39399
   457
haftmann@39392
   458
fun compile_stmts thy stmts_deps =
haftmann@25101
   459
  let
haftmann@25101
   460
    val names = map (fst o fst) stmts_deps;
haftmann@25101
   461
    val names_deps = map (fn ((name, _), deps) => (name, deps)) stmts_deps;
haftmann@25101
   462
    val eqnss = maps (eqns_of_stmt o fst) stmts_deps;
haftmann@26064
   463
    val refl_deps = names_deps
haftmann@25190
   464
      |> maps snd
haftmann@25190
   465
      |> distinct (op =)
haftmann@26064
   466
      |> fold (insert (op =)) names;
haftmann@39392
   467
    fun compile nbe_program = eqnss
haftmann@39392
   468
      |> compile_eqnss thy nbe_program refl_deps
haftmann@39392
   469
      |> rpair nbe_program;
haftmann@25101
   470
  in
haftmann@39399
   471
    fold ensure_const_idx refl_deps
haftmann@26064
   472
    #> apfst (fold (fn (name, deps) => fold (curry Graph.add_edge name) deps) names_deps
haftmann@26064
   473
      #> compile
haftmann@26064
   474
      #-> fold (fn (name, univ) => (Graph.map_node name o apfst) (K (SOME univ))))
haftmann@25101
   475
  end;
haftmann@24155
   476
haftmann@39392
   477
fun compile_program thy program =
haftmann@25101
   478
  let
haftmann@39392
   479
    fun add_stmts names (nbe_program, (maxidx, idx_tab)) = if exists ((can o Graph.get_node) nbe_program) names
haftmann@39392
   480
      then (nbe_program, (maxidx, idx_tab))
haftmann@39392
   481
      else (nbe_program, (maxidx, idx_tab))
haftmann@39392
   482
        |> compile_stmts thy (map (fn name => ((name, Graph.get_node program name),
haftmann@27103
   483
          Graph.imm_succs program name)) names);
haftmann@28706
   484
  in
haftmann@28706
   485
    fold_rev add_stmts (Graph.strong_conn program)
haftmann@28706
   486
  end;
haftmann@24155
   487
haftmann@25944
   488
haftmann@25944
   489
(** evaluation **)
haftmann@25944
   490
haftmann@39392
   491
(* term evaluation by compilation *)
haftmann@25944
   492
haftmann@39392
   493
fun compile_term thy nbe_program deps (vs : (string * sort) list, t) =
haftmann@25924
   494
  let 
haftmann@25924
   495
    val dict_frees = maps (fn (v, sort) => map_index (curry DFree v o fst) sort) vs;
haftmann@25924
   496
  in
haftmann@31064
   497
    ("", (vs, [([], t)]))
haftmann@39392
   498
    |> singleton (compile_eqnss thy nbe_program deps)
haftmann@25924
   499
    |> snd
haftmann@31064
   500
    |> (fn t => apps t (rev dict_frees))
haftmann@25924
   501
  end;
haftmann@24155
   502
haftmann@35371
   503
haftmann@39392
   504
(* reconstruction *)
haftmann@24155
   505
haftmann@30947
   506
fun typ_of_itype program vs (ityco `%% itys) =
haftmann@30947
   507
      let
haftmann@30947
   508
        val Code_Thingol.Datatype (tyco, _) = Graph.get_node program ityco;
haftmann@30947
   509
      in Type (tyco, map (typ_of_itype program vs) itys) end
haftmann@30947
   510
  | typ_of_itype program vs (ITyVar v) =
haftmann@30947
   511
      let
haftmann@30947
   512
        val sort = (the o AList.lookup (op =) vs) v;
haftmann@30947
   513
      in TFree ("'" ^ v, sort) end;
haftmann@30947
   514
haftmann@28663
   515
fun term_of_univ thy program idx_tab t =
haftmann@24155
   516
  let
haftmann@25101
   517
    fun take_until f [] = []
haftmann@25101
   518
      | take_until f (x::xs) = if f x then [] else x :: take_until f xs;
haftmann@28663
   519
    fun is_dict (Const (idx, _)) = (case (Graph.get_node program o the o Inttab.lookup idx_tab) idx
haftmann@28663
   520
         of Code_Thingol.Class _ => true
haftmann@28663
   521
          | Code_Thingol.Classrel _ => true
haftmann@28663
   522
          | Code_Thingol.Classinst _ => true
haftmann@28663
   523
          | _ => false)
haftmann@25101
   524
      | is_dict (DFree _) = true
haftmann@25101
   525
      | is_dict _ = false;
haftmann@28663
   526
    fun const_of_idx idx = (case (Graph.get_node program o the o Inttab.lookup idx_tab) idx
haftmann@35371
   527
     of Code_Thingol.Fun (c, _) => c
haftmann@35371
   528
      | Code_Thingol.Datatypecons (c, _) => c
haftmann@35371
   529
      | Code_Thingol.Classparam (c, _) => c);
haftmann@24155
   530
    fun of_apps bounds (t, ts) =
haftmann@24155
   531
      fold_map (of_univ bounds) ts
haftmann@24155
   532
      #>> (fn ts' => list_comb (t, rev ts'))
haftmann@26064
   533
    and of_univ bounds (Const (idx, ts)) typidx =
haftmann@24155
   534
          let
haftmann@25101
   535
            val ts' = take_until is_dict ts;
haftmann@28663
   536
            val c = const_of_idx idx;
haftmann@31957
   537
            val T = map_type_tvar (fn ((v, i), _) =>
wenzelm@37145
   538
              Type_Infer.param typidx (v ^ string_of_int i, []))
haftmann@31957
   539
                (Sign.the_const_type thy c);
haftmann@30022
   540
            val typidx' = typidx + 1;
haftmann@31957
   541
          in of_apps bounds (Term.Const (c, T), ts') typidx' end
haftmann@27499
   542
      | of_univ bounds (BVar (n, ts)) typidx =
haftmann@27499
   543
          of_apps bounds (Bound (bounds - n - 1), ts) typidx
haftmann@24155
   544
      | of_univ bounds (t as Abs _) typidx =
haftmann@24155
   545
          typidx
haftmann@25924
   546
          |> of_univ (bounds + 1) (apps t [BVar (bounds, [])])
haftmann@24155
   547
          |-> (fn t' => pair (Term.Abs ("u", dummyT, t')))
haftmann@24155
   548
  in of_univ 0 t 0 |> fst end;
haftmann@24155
   549
haftmann@35371
   550
haftmann@39392
   551
(* evaluation with type reconstruction *)
haftmann@39392
   552
haftmann@39392
   553
fun eval_term thy program (nbe_program, idx_tab) ((vs0, (vs, ty)), t) deps =
haftmann@39392
   554
  let
haftmann@39392
   555
    val ctxt = Syntax.init_pretty_global thy;
haftmann@39392
   556
    val string_of_term = Syntax.string_of_term (Config.put show_types true ctxt);
haftmann@39392
   557
    val ty' = typ_of_itype program vs0 ty;
haftmann@39392
   558
    fun type_infer t = singleton
haftmann@39392
   559
      (Type_Infer.infer_types ctxt (try (Type.strip_sorts o Sign.the_const_type thy)) (K NONE))
haftmann@39392
   560
      (Type.constraint ty' t);
haftmann@39392
   561
    fun check_tvars t =
haftmann@39392
   562
      if null (Term.add_tvars t []) then t
haftmann@39392
   563
      else error ("Illegal schematic type variables in normalized term: " ^ string_of_term t);
haftmann@39392
   564
  in
haftmann@39392
   565
    compile_term thy nbe_program deps (vs, t)
haftmann@39392
   566
    |> term_of_univ thy program idx_tab
haftmann@39392
   567
    |> traced (fn t => "Normalized:\n" ^ string_of_term t)
haftmann@39392
   568
    |> type_infer
haftmann@39392
   569
    |> traced (fn t => "Types inferred:\n" ^ string_of_term t)
haftmann@39392
   570
    |> check_tvars
haftmann@39392
   571
    |> traced (fn _ => "---\n")
haftmann@39392
   572
  end;
haftmann@39392
   573
haftmann@39436
   574
haftmann@25101
   575
(* function store *)
haftmann@25101
   576
haftmann@34173
   577
structure Nbe_Functions = Code_Data
haftmann@25101
   578
(
haftmann@35500
   579
  type T = (Univ option * int) Graph.T * (int * string Inttab.table);
haftmann@35500
   580
  val empty = (Graph.empty, (0, Inttab.empty));
haftmann@25101
   581
);
haftmann@25101
   582
haftmann@39399
   583
fun compile ignore_cache thy program =
haftmann@24155
   584
  let
haftmann@39392
   585
    val (nbe_program, (_, idx_tab)) =
haftmann@39399
   586
      Nbe_Functions.change (if ignore_cache then NONE else SOME thy)
haftmann@39399
   587
        (compile_program thy program);
haftmann@39392
   588
  in (nbe_program, idx_tab) end;
haftmann@24155
   589
haftmann@32544
   590
haftmann@39396
   591
(* dynamic evaluation oracle *)
haftmann@24155
   592
haftmann@30947
   593
fun mk_equals thy lhs raw_rhs =
haftmann@26747
   594
  let
haftmann@30947
   595
    val ty = Thm.typ_of (Thm.ctyp_of_term lhs);
haftmann@30947
   596
    val eq = Thm.cterm_of thy (Term.Const ("==", ty --> ty --> propT));
haftmann@30947
   597
    val rhs = Thm.cterm_of thy raw_rhs;
haftmann@30947
   598
  in Thm.mk_binop eq lhs rhs end;
haftmann@26747
   599
haftmann@38669
   600
val (_, raw_oracle) = Context.>>> (Context.map_theory_result
haftmann@39399
   601
  (Thm.add_oracle (Binding.name "normalization_by_evaluation",
haftmann@39399
   602
    fn (thy, program, nbe_program_idx_tab, vsp_ty_t, deps, ct) =>
haftmann@39399
   603
      mk_equals thy ct (eval_term thy program nbe_program_idx_tab vsp_ty_t deps))));
haftmann@31064
   604
haftmann@39399
   605
fun oracle thy program nbe_program_idx_tab vsp_ty_t deps ct =
haftmann@39399
   606
  raw_oracle (thy, program, nbe_program_idx_tab, vsp_ty_t, deps, ct);
haftmann@30942
   607
haftmann@39606
   608
val dynamic_eval_conv = Conv.tap_thy (fn thy =>
haftmann@39606
   609
  lift_triv_classes_conv thy (Code_Thingol.dynamic_eval_conv thy
haftmann@39606
   610
    (K (fn program => oracle thy program (compile false thy program)))));
haftmann@24155
   611
haftmann@38669
   612
fun dynamic_eval_value thy = lift_triv_classes_rew thy
haftmann@39606
   613
  (Code_Thingol.dynamic_eval_value thy I
haftmann@39606
   614
    (K (fn program => eval_term thy program (compile false thy program))));
haftmann@39399
   615
haftmann@39606
   616
fun static_eval_conv thy consts =
haftmann@39606
   617
  lift_triv_classes_conv thy (Code_Thingol.static_eval_conv thy consts
haftmann@39475
   618
    (K (fn program => let val nbe_program = compile true thy program
haftmann@39606
   619
      in fn thy => oracle thy program nbe_program end)));
haftmann@24839
   620
haftmann@35371
   621
haftmann@39396
   622
(** setup **)
haftmann@24155
   623
haftmann@38669
   624
val setup = Value.add_evaluator ("nbe", dynamic_eval_value o ProofContext.theory_of);
haftmann@24155
   625
haftmann@24155
   626
end;
haftmann@28337
   627