src/HOL/Tools/Sledgehammer/sledgehammer_filter.ML
author blanchet
Sat Dec 18 21:07:34 2010 +0100 (2010-12-18 ago)
changeset 41273 35ce17cd7967
parent 41211 1e2e16bc0077
child 41279 e0400b05a62c
permissions -rw-r--r--
made the relevance filter treat unatomizable facts like "atomize_all" properly (these result in problems that get E spinning seemingly forever);
disabled inductions (E and SPASS don't like them), but kept "ext" (seems more harmless)
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(*  Title:      HOL/Tools/Sledgehammer/sledgehammer_filter.ML
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    Author:     Jia Meng, Cambridge University Computer Laboratory and NICTA
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    Author:     Jasmin Blanchette, TU Muenchen
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Sledgehammer's relevance filter.
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*)
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signature SLEDGEHAMMER_FILTER =
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sig
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  datatype locality = General | Intro | Elim | Simp | Local | Assum | Chained
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  type relevance_fudge =
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    {allow_ext : bool,
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     worse_irrel_freq : real,
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     higher_order_irrel_weight : real,
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     abs_rel_weight : real,
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     abs_irrel_weight : real,
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     skolem_irrel_weight : real,
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     theory_const_rel_weight : real,
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     theory_const_irrel_weight : real,
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     intro_bonus : real,
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     elim_bonus : real,
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     simp_bonus : real,
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     local_bonus : real,
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     assum_bonus : real,
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     chained_bonus : real,
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     max_imperfect : real,
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     max_imperfect_exp : real,
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     threshold_divisor : real,
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     ridiculous_threshold : real}
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  type relevance_override =
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    {add : (Facts.ref * Attrib.src list) list,
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     del : (Facts.ref * Attrib.src list) list,
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     only : bool}
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  val trace : bool Unsynchronized.ref
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  val fact_from_ref :
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    Proof.context -> unit Symtab.table -> thm list
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    -> Facts.ref * Attrib.src list -> ((string * locality) * thm) list
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  val relevant_facts :
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    Proof.context -> bool -> real * real -> int
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    -> (string * typ -> term list -> bool) -> relevance_fudge
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    -> relevance_override -> thm list -> term list -> term
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    -> ((string * locality) * thm) list
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end;
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structure Sledgehammer_Filter : SLEDGEHAMMER_FILTER =
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struct
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open Sledgehammer_Util
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val trace = Unsynchronized.ref false
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fun trace_msg msg = if !trace then tracing (msg ()) else ()
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(* experimental features *)
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val respect_no_atp = true
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val instantiate_inducts = false
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datatype locality = General | Intro | Elim | Simp | Local | Assum | Chained
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type relevance_fudge =
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  {allow_ext : bool,
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   worse_irrel_freq : real,
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   higher_order_irrel_weight : real,
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   abs_rel_weight : real,
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   abs_irrel_weight : real,
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   skolem_irrel_weight : real,
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   theory_const_rel_weight : real,
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   theory_const_irrel_weight : real,
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   intro_bonus : real,
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   elim_bonus : real,
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   simp_bonus : real,
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   local_bonus : real,
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   assum_bonus : real,
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   chained_bonus : real,
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   max_imperfect : real,
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   max_imperfect_exp : real,
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   threshold_divisor : real,
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   ridiculous_threshold : real}
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type relevance_override =
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  {add : (Facts.ref * Attrib.src list) list,
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   del : (Facts.ref * Attrib.src list) list,
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   only : bool}
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val sledgehammer_prefix = "Sledgehammer" ^ Long_Name.separator
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val abs_name = sledgehammer_prefix ^ "abs"
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val skolem_prefix = sledgehammer_prefix ^ "sko"
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val theory_const_suffix = Long_Name.separator ^ " 1"
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fun needs_quoting reserved s =
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  Symtab.defined reserved s orelse
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  exists (not o Syntax.is_identifier) (Long_Name.explode s)
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fun make_name reserved multi j name =
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  (name |> needs_quoting reserved name ? quote) ^
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  (if multi then "(" ^ Int.toString j ^ ")" else "")
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fun explode_interval _ (Facts.FromTo (i, j)) = i upto j
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  | explode_interval max (Facts.From i) = i upto i + max - 1
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  | explode_interval _ (Facts.Single i) = [i]
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fun fact_from_ref ctxt reserved chained_ths (xthm as (xref, args)) =
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  let
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    val ths = Attrib.eval_thms ctxt [xthm]
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    val bracket =
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      implode (map (fn arg => "[" ^ Pretty.str_of (Args.pretty_src ctxt arg)
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                               ^ "]") args)
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    fun nth_name j =
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      case xref of
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        Facts.Fact s => "`" ^ s ^ "`" ^ bracket
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      | Facts.Named (("", _), _) => "[" ^ bracket ^ "]"
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      | Facts.Named ((name, _), NONE) =>
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        make_name reserved (length ths > 1) (j + 1) name ^ bracket
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      | Facts.Named ((name, _), SOME intervals) =>
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        make_name reserved true
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                 (nth (maps (explode_interval (length ths)) intervals) j) name ^
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        bracket
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  in
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    (ths, (0, []))
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    |-> fold (fn th => fn (j, rest) =>
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                 (j + 1, ((nth_name j,
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                          if member Thm.eq_thm chained_ths th then Chained
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                          else General), th) :: rest))
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    |> snd
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  end
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(* This is a terrible hack. Free variables are sometimes code as "M__" when they
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   are displayed as "M" and we want to avoid clashes with these. But sometimes
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   it's even worse: "Ma__" encodes "M". So we simply reserve all prefixes of all
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   free variables. In the worse case scenario, where the fact won't be resolved
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   correctly, the user can fix it manually, e.g., by naming the fact in
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   question. Ideally we would need nothing of it, but backticks just don't work
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   with schematic variables. *)
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fun all_prefixes_of s =
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  map (fn i => String.extract (s, 0, SOME i)) (1 upto size s - 1)
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fun close_form t =
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  (t, [] |> Term.add_free_names t |> maps all_prefixes_of)
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  |> fold (fn ((s, i), T) => fn (t', taken) =>
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              let val s' = Name.variant taken s in
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                ((if fastype_of t' = HOLogic.boolT then HOLogic.all_const
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                  else Term.all) T
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                 $ Abs (s', T, abstract_over (Var ((s, i), T), t')),
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                 s' :: taken)
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              end)
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          (Term.add_vars t [] |> sort_wrt (fst o fst))
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  |> fst
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fun string_for_term ctxt t =
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  Print_Mode.setmp (filter (curry (op =) Symbol.xsymbolsN)
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                   (print_mode_value ())) (Syntax.string_of_term ctxt) t
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  |> String.translate (fn c => if Char.isPrint c then str c else "")
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  |> simplify_spaces
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(** Structural induction rules **)
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fun struct_induct_rule_on th =
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  case Logic.strip_horn (prop_of th) of
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    (prems, @{const Trueprop}
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            $ ((p as Var ((p_name, 0), _)) $ (a as Var (_, ind_T)))) =>
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    if not (is_TVar ind_T) andalso length prems > 1 andalso
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       exists (exists_subterm (curry (op aconv) p)) prems andalso
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       not (exists (exists_subterm (curry (op aconv) a)) prems) then
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      SOME (p_name, ind_T)
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    else
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      NONE
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  | _ => NONE
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fun instantiate_induct_rule ctxt concl_prop p_name ((name, loc), (multi, th))
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                            ind_x =
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  let
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    fun varify_noninducts (t as Free (s, T)) =
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        if (s, T) = ind_x orelse can dest_funT T then t else Var ((s, 0), T)
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      | varify_noninducts t = t
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    val p_inst =
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      concl_prop |> map_aterms varify_noninducts |> close_form
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                 |> lambda (Free ind_x)
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                 |> string_for_term ctxt
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  in
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    ((fn () => name () ^ "[where " ^ p_name ^ " = " ^ quote p_inst ^ "]", loc),
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     (multi, th |> read_instantiate ctxt [((p_name, 0), p_inst)]))
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  end
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fun type_match thy (T1, T2) =
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  (Sign.typ_match thy (T2, T1) Vartab.empty; true)
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  handle Type.TYPE_MATCH => false
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fun instantiate_if_induct_rule ctxt stmt stmt_xs (ax as (_, (_, th))) =
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  case struct_induct_rule_on th of
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    SOME (p_name, ind_T) =>
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    let val thy = ProofContext.theory_of ctxt in
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      stmt_xs |> filter (fn (_, T) => type_match thy (T, ind_T))
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              |> map_filter (try (instantiate_induct_rule ctxt stmt p_name ax))
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    end
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  | NONE => [ax]
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(***************************************************************)
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(* Relevance Filtering                                         *)
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(***************************************************************)
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(*** constants with types ***)
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fun order_of_type (Type (@{type_name fun}, [T1, @{typ bool}])) =
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    order_of_type T1 (* cheat: pretend sets are first-order *)
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  | order_of_type (Type (@{type_name fun}, [T1, T2])) =
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    Int.max (order_of_type T1 + 1, order_of_type T2)
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  | order_of_type (Type (_, Ts)) = fold (Integer.max o order_of_type) Ts 0
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  | order_of_type _ = 0
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(* An abstraction of Isabelle types and first-order terms *)
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datatype pattern = PVar | PApp of string * pattern list
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datatype ptype = PType of int * pattern list
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fun string_for_pattern PVar = "_"
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  | string_for_pattern (PApp (s, ps)) =
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    if null ps then s else s ^ string_for_patterns ps
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and string_for_patterns ps = "(" ^ commas (map string_for_pattern ps) ^ ")"
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fun string_for_ptype (PType (_, ps)) = string_for_patterns ps
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(*Is the second type an instance of the first one?*)
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fun match_pattern (PVar, _) = true
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  | match_pattern (PApp _, PVar) = false
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  | match_pattern (PApp (s, ps), PApp (t, qs)) =
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    s = t andalso match_patterns (ps, qs)
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and match_patterns (_, []) = true
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  | match_patterns ([], _) = false
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  | match_patterns (p :: ps, q :: qs) =
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    match_pattern (p, q) andalso match_patterns (ps, qs)
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fun match_ptype (PType (_, ps), PType (_, qs)) = match_patterns (ps, qs)
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(* Is there a unifiable constant? *)
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fun pconst_mem f consts (s, ps) =
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  exists (curry (match_ptype o f) ps)
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         (map snd (filter (curry (op =) s o fst) consts))
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fun pconst_hyper_mem f const_tab (s, ps) =
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  exists (curry (match_ptype o f) ps) (these (Symtab.lookup const_tab s))
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fun pattern_for_type (Type (s, Ts)) = PApp (s, map pattern_for_type Ts)
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  | pattern_for_type (TFree (s, _)) = PApp (s, [])
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  | pattern_for_type (TVar _) = PVar
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(* Pairs a constant with the list of its type instantiations. *)
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fun ptype thy const x =
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  (if const then map pattern_for_type (these (try (Sign.const_typargs thy) x))
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   else [])
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fun rich_ptype thy const (s, T) =
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  PType (order_of_type T, ptype thy const (s, T))
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fun rich_pconst thy const (s, T) = (s, rich_ptype thy const (s, T))
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fun string_for_hyper_pconst (s, ps) =
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  s ^ "{" ^ commas (map string_for_ptype ps) ^ "}"
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(* Add a pconstant to the table, but a [] entry means a standard
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   connective, which we ignore.*)
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fun add_pconst_to_table also_skolem (s, p) =
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  if (not also_skolem andalso String.isPrefix skolem_prefix s) then I
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  else Symtab.map_default (s, [p]) (insert (op =) p)
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fun pconsts_in_terms thy is_built_in_const also_skolems pos ts =
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  let
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    val flip = Option.map not
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    (* We include free variables, as well as constants, to handle locales. For
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       each quantifiers that must necessarily be skolemized by the automatic
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       prover, we introduce a fresh constant to simulate the effect of
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       Skolemization. *)
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    fun do_const const x ts =
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      (not (is_built_in_const x ts)
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       ? add_pconst_to_table also_skolems (rich_pconst thy const x))
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      #> fold do_term ts
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    and do_term t =
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      case strip_comb t of
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        (Const x, ts) => do_const true x ts
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      | (Free x, ts) => do_const false x ts
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      | (Abs (_, T, t'), ts) =>
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        (null ts
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         ? add_pconst_to_table true (abs_name, PType (order_of_type T + 1, [])))
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        #> fold do_term (t' :: ts)
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      | (_, ts) => fold do_term ts
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    fun do_quantifier will_surely_be_skolemized abs_T body_t =
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      do_formula pos body_t
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      #> (if also_skolems andalso will_surely_be_skolemized then
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            add_pconst_to_table true
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                (gensym skolem_prefix, PType (order_of_type abs_T, []))
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          else
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            I)
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    and do_term_or_formula T =
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      if T = HOLogic.boolT then do_formula NONE else do_term
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    and do_formula pos t =
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      case t of
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        Const (@{const_name all}, _) $ Abs (_, T, t') =>
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        do_quantifier (pos = SOME false) T t'
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      | @{const "==>"} $ t1 $ t2 =>
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        do_formula (flip pos) t1 #> do_formula pos t2
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      | Const (@{const_name "=="}, Type (_, [T, _])) $ t1 $ t2 =>
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        fold (do_term_or_formula T) [t1, t2]
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      | @{const Trueprop} $ t1 => do_formula pos t1
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      | @{const False} => I
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      | @{const True} => I
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      | @{const Not} $ t1 => do_formula (flip pos) t1
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      | Const (@{const_name All}, _) $ Abs (_, T, t') =>
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        do_quantifier (pos = SOME false) T t'
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      | Const (@{const_name Ex}, _) $ Abs (_, T, t') =>
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        do_quantifier (pos = SOME true) T t'
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      | @{const HOL.conj} $ t1 $ t2 => fold (do_formula pos) [t1, t2]
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      | @{const HOL.disj} $ t1 $ t2 => fold (do_formula pos) [t1, t2]
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      | @{const HOL.implies} $ t1 $ t2 =>
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        do_formula (flip pos) t1 #> do_formula pos t2
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      | Const (@{const_name HOL.eq}, Type (_, [T, _])) $ t1 $ t2 =>
blanchet@38587
   310
        fold (do_term_or_formula T) [t1, t2]
blanchet@38587
   311
      | Const (@{const_name If}, Type (_, [_, Type (_, [T, _])]))
blanchet@38587
   312
        $ t1 $ t2 $ t3 =>
blanchet@38587
   313
        do_formula NONE t1 #> fold (do_term_or_formula T) [t2, t3]
blanchet@38939
   314
      | Const (@{const_name Ex1}, _) $ Abs (_, T, t') =>
blanchet@38939
   315
        do_quantifier (is_some pos) T t'
blanchet@38939
   316
      | Const (@{const_name Ball}, _) $ t1 $ Abs (_, T, t') =>
blanchet@38939
   317
        do_quantifier (pos = SOME false) T
blanchet@38939
   318
                      (HOLogic.mk_imp (incr_boundvars 1 t1 $ Bound 0, t'))
blanchet@38939
   319
      | Const (@{const_name Bex}, _) $ t1 $ Abs (_, T, t') =>
blanchet@38939
   320
        do_quantifier (pos = SOME true) T
blanchet@38939
   321
                      (HOLogic.mk_conj (incr_boundvars 1 t1 $ Bound 0, t'))
blanchet@37537
   322
      | (t0 as Const (_, @{typ bool})) $ t1 =>
blanchet@37537
   323
        do_term t0 #> do_formula pos t1  (* theory constant *)
blanchet@37537
   324
      | _ => do_term t
blanchet@38819
   325
  in Symtab.empty |> fold (do_formula pos) ts end
paulson@24287
   326
paulson@24287
   327
(*Inserts a dummy "constant" referring to the theory name, so that relevance
paulson@24287
   328
  takes the given theory into account.*)
blanchet@41200
   329
fun theory_constify ({theory_const_rel_weight, theory_const_irrel_weight, ...}
blanchet@41200
   330
                     : relevance_fudge) thy_name t =
blanchet@40070
   331
  if exists (curry (op <) 0.0) [theory_const_rel_weight,
blanchet@40070
   332
                                theory_const_irrel_weight] then
blanchet@41200
   333
    Const (thy_name ^ theory_const_suffix, @{typ bool}) $ t
blanchet@37505
   334
  else
blanchet@41200
   335
    t
blanchet@41200
   336
blanchet@41200
   337
fun theory_const_prop_of fudge th =
blanchet@41200
   338
  theory_constify fudge (Context.theory_name (theory_of_thm th)) (prop_of th)
blanchet@37505
   339
paulson@24287
   340
(**** Constant / Type Frequencies ****)
paulson@24287
   341
blanchet@38743
   342
(* A two-dimensional symbol table counts frequencies of constants. It's keyed
blanchet@38743
   343
   first by constant name and second by its list of type instantiations. For the
blanchet@38823
   344
   latter, we need a linear ordering on "pattern list". *)
paulson@24287
   345
blanchet@38823
   346
fun pattern_ord p =
blanchet@38743
   347
  case p of
blanchet@38744
   348
    (PVar, PVar) => EQUAL
blanchet@38823
   349
  | (PVar, PApp _) => LESS
blanchet@38823
   350
  | (PApp _, PVar) => GREATER
blanchet@38823
   351
  | (PApp q1, PApp q2) =>
blanchet@38823
   352
    prod_ord fast_string_ord (dict_ord pattern_ord) (q1, q2)
blanchet@38939
   353
fun ptype_ord (PType p, PType q) =
blanchet@38939
   354
  prod_ord (dict_ord pattern_ord) int_ord (swap p, swap q)
paulson@24287
   355
blanchet@38939
   356
structure PType_Tab = Table(type key = ptype val ord = ptype_ord)
paulson@24287
   357
blanchet@40204
   358
fun count_fact_consts thy fudge =
blanchet@37503
   359
  let
blanchet@38827
   360
    fun do_const const (s, T) ts =
blanchet@38827
   361
      (* Two-dimensional table update. Constant maps to types maps to count. *)
blanchet@41204
   362
      PType_Tab.map_default (rich_ptype thy const (s, T), 0) (Integer.add 1)
blanchet@38939
   363
      |> Symtab.map_default (s, PType_Tab.empty)
blanchet@38827
   364
      #> fold do_term ts
blanchet@38827
   365
    and do_term t =
blanchet@38827
   366
      case strip_comb t of
blanchet@38827
   367
        (Const x, ts) => do_const true x ts
blanchet@38827
   368
      | (Free x, ts) => do_const false x ts
blanchet@38827
   369
      | (Abs (_, _, t'), ts) => fold do_term (t' :: ts)
blanchet@38827
   370
      | (_, ts) => fold do_term ts
blanchet@40070
   371
  in do_term o theory_const_prop_of fudge o snd end
paulson@24287
   372
paulson@24287
   373
paulson@24287
   374
(**** Actual Filtering Code ****)
paulson@24287
   375
blanchet@39367
   376
fun pow_int _ 0 = 1.0
blanchet@38939
   377
  | pow_int x 1 = x
blanchet@38939
   378
  | pow_int x n = if n > 0 then x * pow_int x (n - 1) else pow_int x (n + 1) / x
blanchet@38939
   379
paulson@24287
   380
(*The frequency of a constant is the sum of those of all instances of its type.*)
blanchet@38824
   381
fun pconst_freq match const_tab (c, ps) =
blanchet@38939
   382
  PType_Tab.fold (fn (qs, m) => match (ps, qs) ? Integer.add m)
blanchet@38939
   383
                 (the (Symtab.lookup const_tab c)) 0
blanchet@38686
   384
paulson@24287
   385
blanchet@38085
   386
(* A surprising number of theorems contain only a few significant constants.
blanchet@38085
   387
   These include all induction rules, and other general theorems. *)
blanchet@37503
   388
blanchet@37503
   389
(* "log" seems best in practice. A constant function of one ignores the constant
blanchet@38938
   390
   frequencies. Rare constants give more points if they are relevant than less
blanchet@38938
   391
   rare ones. *)
blanchet@39367
   392
fun rel_weight_for _ freq = 1.0 + 2.0 / Math.ln (Real.fromInt freq + 1.0)
blanchet@38938
   393
blanchet@38938
   394
(* Irrelevant constants are treated differently. We associate lower penalties to
blanchet@38938
   395
   very rare constants and very common ones -- the former because they can't
blanchet@38938
   396
   lead to the inclusion of too many new facts, and the latter because they are
blanchet@38938
   397
   so common as to be of little interest. *)
blanchet@40070
   398
fun irrel_weight_for ({worse_irrel_freq, higher_order_irrel_weight, ...}
blanchet@40070
   399
                      : relevance_fudge) order freq =
blanchet@40070
   400
  let val (k, x) = worse_irrel_freq |> `Real.ceil in
blanchet@38939
   401
    (if freq < k then Math.ln (Real.fromInt (freq + 1)) / Math.ln x
blanchet@38939
   402
     else rel_weight_for order freq / rel_weight_for order k)
blanchet@40070
   403
    * pow_int higher_order_irrel_weight (order - 1)
blanchet@38938
   404
  end
blanchet@37503
   405
blanchet@37503
   406
(* Computes a constant's weight, as determined by its frequency. *)
blanchet@38992
   407
fun generic_pconst_weight abs_weight skolem_weight theory_const_weight
blanchet@38992
   408
                          weight_for f const_tab (c as (s, PType (m, _))) =
blanchet@38816
   409
  if s = abs_name then abs_weight
blanchet@38816
   410
  else if String.isPrefix skolem_prefix s then skolem_weight
blanchet@38992
   411
  else if String.isSuffix theory_const_suffix s then theory_const_weight
blanchet@38939
   412
  else weight_for m (pconst_freq (match_ptype o f) const_tab c)
blanchet@38821
   413
blanchet@40070
   414
fun rel_pconst_weight ({abs_rel_weight, theory_const_rel_weight, ...}
blanchet@40070
   415
                       : relevance_fudge) const_tab =
blanchet@40070
   416
  generic_pconst_weight abs_rel_weight 0.0 theory_const_rel_weight
blanchet@38992
   417
                        rel_weight_for I const_tab
blanchet@40070
   418
fun irrel_pconst_weight (fudge as {abs_irrel_weight, skolem_irrel_weight,
blanchet@40070
   419
                                   theory_const_irrel_weight, ...}) const_tab =
blanchet@40070
   420
  generic_pconst_weight abs_irrel_weight skolem_irrel_weight
blanchet@40070
   421
                        theory_const_irrel_weight (irrel_weight_for fudge) swap
blanchet@40070
   422
                        const_tab
paulson@24287
   423
blanchet@40070
   424
fun locality_bonus (_ : relevance_fudge) General = 0.0
blanchet@40070
   425
  | locality_bonus {intro_bonus, ...} Intro = intro_bonus
blanchet@40070
   426
  | locality_bonus {elim_bonus, ...} Elim = elim_bonus
blanchet@40070
   427
  | locality_bonus {simp_bonus, ...} Simp = simp_bonus
blanchet@40070
   428
  | locality_bonus {local_bonus, ...} Local = local_bonus
blanchet@40070
   429
  | locality_bonus {assum_bonus, ...} Assum = assum_bonus
blanchet@40070
   430
  | locality_bonus {chained_bonus, ...} Chained = chained_bonus
blanchet@38751
   431
blanchet@40418
   432
fun is_odd_const_name s =
blanchet@40418
   433
  s = abs_name orelse String.isPrefix skolem_prefix s orelse
blanchet@40418
   434
  String.isSuffix theory_const_suffix s
blanchet@40418
   435
blanchet@40204
   436
fun fact_weight fudge loc const_tab relevant_consts fact_consts =
blanchet@40204
   437
  case fact_consts |> List.partition (pconst_hyper_mem I relevant_consts)
blanchet@40204
   438
                   ||> filter_out (pconst_hyper_mem swap relevant_consts) of
blanchet@38827
   439
    ([], _) => 0.0
blanchet@38744
   440
  | (rel, irrel) =>
blanchet@40418
   441
    if forall (forall (is_odd_const_name o fst)) [rel, irrel] then
blanchet@40371
   442
      0.0
blanchet@40371
   443
    else
blanchet@40371
   444
      let
blanchet@40371
   445
        val irrel = irrel |> filter_out (pconst_mem swap rel)
blanchet@40371
   446
        val rel_weight =
blanchet@40371
   447
          0.0 |> fold (curry (op +) o rel_pconst_weight fudge const_tab) rel
blanchet@40371
   448
        val irrel_weight =
blanchet@40371
   449
          ~ (locality_bonus fudge loc)
blanchet@40371
   450
          |> fold (curry (op +) o irrel_pconst_weight fudge const_tab) irrel
blanchet@40371
   451
        val res = rel_weight / (rel_weight + irrel_weight)
blanchet@40371
   452
      in if Real.isFinite res then res else 0.0 end
blanchet@38747
   453
blanchet@40369
   454
fun pconsts_in_fact thy is_built_in_const t =
blanchet@38825
   455
  Symtab.fold (fn (s, pss) => fold (cons o pair s) pss)
blanchet@40369
   456
              (pconsts_in_terms thy is_built_in_const true (SOME true) [t]) []
blanchet@40369
   457
fun pair_consts_fact thy is_built_in_const fudge fact =
blanchet@40204
   458
  case fact |> snd |> theory_const_prop_of fudge
blanchet@40369
   459
            |> pconsts_in_fact thy is_built_in_const of
blanchet@38827
   460
    [] => NONE
blanchet@40204
   461
  | consts => SOME ((fact, consts), NONE)
paulson@24287
   462
blanchet@38699
   463
type annotated_thm =
blanchet@38939
   464
  (((unit -> string) * locality) * thm) * (string * ptype) list
blanchet@37505
   465
blanchet@38904
   466
fun take_most_relevant max_relevant remaining_max
blanchet@40070
   467
        ({max_imperfect, max_imperfect_exp, ...} : relevance_fudge) 
blanchet@40070
   468
        (candidates : (annotated_thm * real) list) =
blanchet@38744
   469
  let
blanchet@38747
   470
    val max_imperfect =
blanchet@40070
   471
      Real.ceil (Math.pow (max_imperfect,
blanchet@38904
   472
                    Math.pow (Real.fromInt remaining_max
blanchet@40070
   473
                              / Real.fromInt max_relevant, max_imperfect_exp)))
blanchet@38747
   474
    val (perfect, imperfect) =
blanchet@38889
   475
      candidates |> sort (Real.compare o swap o pairself snd)
blanchet@38889
   476
                 |> take_prefix (fn (_, w) => w > 0.99999)
blanchet@38747
   477
    val ((accepts, more_rejects), rejects) =
blanchet@38747
   478
      chop max_imperfect imperfect |>> append perfect |>> chop remaining_max
blanchet@38744
   479
  in
blanchet@38889
   480
    trace_msg (fn () =>
blanchet@38889
   481
        "Actually passed (" ^ Int.toString (length accepts) ^ " of " ^
blanchet@38889
   482
        Int.toString (length candidates) ^ "): " ^
blanchet@38889
   483
        (accepts |> map (fn ((((name, _), _), _), weight) =>
blanchet@38752
   484
                            name () ^ " [" ^ Real.toString weight ^ "]")
blanchet@38745
   485
                 |> commas));
blanchet@38747
   486
    (accepts, more_rejects @ rejects)
blanchet@38744
   487
  end
paulson@24287
   488
blanchet@40369
   489
fun if_empty_replace_with_locality thy is_built_in_const facts loc tab =
blanchet@38819
   490
  if Symtab.is_empty tab then
blanchet@40369
   491
    pconsts_in_terms thy is_built_in_const false (SOME false)
blanchet@38819
   492
        (map_filter (fn ((_, loc'), th) =>
blanchet@40204
   493
                        if loc' = loc then SOME (prop_of th) else NONE) facts)
blanchet@38819
   494
  else
blanchet@38819
   495
    tab
blanchet@38819
   496
blanchet@41158
   497
fun add_arities is_built_in_const th =
blanchet@41158
   498
  let
blanchet@41158
   499
    fun aux _ _ NONE = NONE
blanchet@41158
   500
      | aux t args (SOME tab) =
blanchet@41158
   501
        case t of
blanchet@41158
   502
          t1 $ t2 => SOME tab |> aux t1 (t2 :: args) |> aux t2 []
blanchet@41158
   503
        | Const (x as (s, _)) =>
blanchet@41158
   504
          (if is_built_in_const x args then
blanchet@41158
   505
             SOME tab
blanchet@41158
   506
           else case Symtab.lookup tab s of
blanchet@41158
   507
             NONE => SOME (Symtab.update (s, length args) tab)
blanchet@41158
   508
           | SOME n => if n = length args then SOME tab else NONE)
blanchet@41158
   509
        | _ => SOME tab
blanchet@41158
   510
  in aux (prop_of th) [] end
blanchet@41158
   511
blanchet@41158
   512
fun needs_ext is_built_in_const facts =
blanchet@41158
   513
  fold (add_arities is_built_in_const o snd) facts (SOME Symtab.empty)
blanchet@41158
   514
  |> is_none
blanchet@41158
   515
blanchet@40369
   516
fun relevance_filter ctxt threshold0 decay max_relevant is_built_in_const
blanchet@40070
   517
        (fudge as {threshold_divisor, ridiculous_threshold, ...})
blanchet@40204
   518
        ({add, del, ...} : relevance_override) facts goal_ts =
blanchet@38739
   519
  let
blanchet@38739
   520
    val thy = ProofContext.theory_of ctxt
blanchet@40204
   521
    val const_tab = fold (count_fact_consts thy fudge) facts Symtab.empty
blanchet@38819
   522
    val goal_const_tab =
blanchet@40369
   523
      pconsts_in_terms thy is_built_in_const false (SOME false) goal_ts
blanchet@40369
   524
      |> fold (if_empty_replace_with_locality thy is_built_in_const facts)
blanchet@38993
   525
              [Chained, Assum, Local]
blanchet@39012
   526
    val add_ths = Attrib.eval_thms ctxt add
blanchet@39012
   527
    val del_ths = Attrib.eval_thms ctxt del
blanchet@40204
   528
    val facts = facts |> filter_out (member Thm.eq_thm del_ths o snd)
blanchet@38747
   529
    fun iter j remaining_max threshold rel_const_tab hopeless hopeful =
blanchet@38739
   530
      let
blanchet@40191
   531
        fun relevant [] _ [] =
blanchet@38747
   532
            (* Nothing has been added this iteration. *)
blanchet@40070
   533
            if j = 0 andalso threshold >= ridiculous_threshold then
blanchet@38747
   534
              (* First iteration? Try again. *)
blanchet@40070
   535
              iter 0 max_relevant (threshold / threshold_divisor) rel_const_tab
blanchet@38747
   536
                   hopeless hopeful
blanchet@38744
   537
            else
blanchet@40191
   538
              []
blanchet@38889
   539
          | relevant candidates rejects [] =
blanchet@38739
   540
            let
blanchet@38747
   541
              val (accepts, more_rejects) =
blanchet@40070
   542
                take_most_relevant max_relevant remaining_max fudge candidates
blanchet@38739
   543
              val rel_const_tab' =
blanchet@38745
   544
                rel_const_tab
blanchet@41066
   545
                |> fold (add_pconst_to_table false) (maps (snd o fst) accepts)
blanchet@38744
   546
              fun is_dirty (c, _) =
blanchet@38744
   547
                Symtab.lookup rel_const_tab' c <> Symtab.lookup rel_const_tab c
blanchet@38745
   548
              val (hopeful_rejects, hopeless_rejects) =
blanchet@38745
   549
                 (rejects @ hopeless, ([], []))
blanchet@38745
   550
                 |-> fold (fn (ax as (_, consts), old_weight) =>
blanchet@38745
   551
                              if exists is_dirty consts then
blanchet@38745
   552
                                apfst (cons (ax, NONE))
blanchet@38745
   553
                              else
blanchet@38745
   554
                                apsnd (cons (ax, old_weight)))
blanchet@38745
   555
                 |>> append (more_rejects
blanchet@38745
   556
                             |> map (fn (ax as (_, consts), old_weight) =>
blanchet@38745
   557
                                        (ax, if exists is_dirty consts then NONE
blanchet@38745
   558
                                             else SOME old_weight)))
blanchet@38747
   559
              val threshold =
blanchet@38822
   560
                1.0 - (1.0 - threshold)
blanchet@38822
   561
                      * Math.pow (decay, Real.fromInt (length accepts))
blanchet@38747
   562
              val remaining_max = remaining_max - length accepts
blanchet@38739
   563
            in
blanchet@38744
   564
              trace_msg (fn () => "New or updated constants: " ^
blanchet@38744
   565
                  commas (rel_const_tab' |> Symtab.dest
blanchet@38822
   566
                          |> subtract (op =) (rel_const_tab |> Symtab.dest)
blanchet@38827
   567
                          |> map string_for_hyper_pconst));
blanchet@38745
   568
              map (fst o fst) accepts @
blanchet@38747
   569
              (if remaining_max = 0 then
blanchet@40191
   570
                 []
blanchet@38745
   571
               else
blanchet@38747
   572
                 iter (j + 1) remaining_max threshold rel_const_tab'
blanchet@38747
   573
                      hopeless_rejects hopeful_rejects)
blanchet@38739
   574
            end
blanchet@38889
   575
          | relevant candidates rejects
blanchet@40204
   576
                     (((ax as (((_, loc), _), fact_consts)), cached_weight)
blanchet@38747
   577
                      :: hopeful) =
blanchet@38739
   578
            let
blanchet@38739
   579
              val weight =
blanchet@38739
   580
                case cached_weight of
blanchet@38739
   581
                  SOME w => w
blanchet@40204
   582
                | NONE => fact_weight fudge loc const_tab rel_const_tab
blanchet@40204
   583
                                      fact_consts
blanchet@38739
   584
            in
blanchet@38741
   585
              if weight >= threshold then
blanchet@38889
   586
                relevant ((ax, weight) :: candidates) rejects hopeful
blanchet@38739
   587
              else
blanchet@38889
   588
                relevant candidates ((ax, weight) :: rejects) hopeful
blanchet@38739
   589
            end
blanchet@38739
   590
        in
blanchet@38744
   591
          trace_msg (fn () =>
blanchet@38744
   592
              "ITERATION " ^ string_of_int j ^ ": current threshold: " ^
blanchet@38744
   593
              Real.toString threshold ^ ", constants: " ^
blanchet@38744
   594
              commas (rel_const_tab |> Symtab.dest
blanchet@38744
   595
                      |> filter (curry (op <>) [] o snd)
blanchet@38827
   596
                      |> map string_for_hyper_pconst));
blanchet@38889
   597
          relevant [] [] hopeful
blanchet@38739
   598
        end
blanchet@41158
   599
    fun add_facts ths accepts =
blanchet@41167
   600
      (facts |> filter (member Thm.eq_thm ths o snd)) @
blanchet@41167
   601
      (accepts |> filter_out (member Thm.eq_thm ths o snd))
blanchet@40408
   602
      |> take max_relevant
blanchet@38739
   603
  in
blanchet@40369
   604
    facts |> map_filter (pair_consts_fact thy is_built_in_const fudge)
blanchet@40204
   605
          |> iter 0 max_relevant threshold0 goal_const_tab []
blanchet@41158
   606
          |> not (null add_ths) ? add_facts add_ths
blanchet@41158
   607
          |> (fn accepts =>
blanchet@41158
   608
                 accepts |> needs_ext is_built_in_const accepts
blanchet@41158
   609
                            ? add_facts @{thms ext})
blanchet@41158
   610
          |> tap (fn accepts => trace_msg (fn () =>
blanchet@41158
   611
                      "Total relevant: " ^ Int.toString (length accepts)))
blanchet@38739
   612
  end
paulson@24287
   613
blanchet@38744
   614
paulson@24287
   615
(***************************************************************)
mengj@19768
   616
(* Retrieving and filtering lemmas                             *)
mengj@19768
   617
(***************************************************************)
mengj@19768
   618
paulson@33022
   619
(*** retrieve lemmas and filter them ***)
mengj@19768
   620
paulson@20757
   621
(*Reject theorems with names like "List.filter.filter_list_def" or
paulson@21690
   622
  "Accessible_Part.acc.defs", as these are definitions arising from packages.*)
paulson@20757
   623
fun is_package_def a =
blanchet@40205
   624
  let val names = Long_Name.explode a in
blanchet@40205
   625
    (length names > 2 andalso not (hd names = "local") andalso
blanchet@40205
   626
     String.isSuffix "_def" a) orelse String.isSuffix "_defs" a
blanchet@40205
   627
  end
paulson@20757
   628
blanchet@38937
   629
fun mk_fact_table f xs =
blanchet@38937
   630
  fold (Termtab.update o `(prop_of o f)) xs Termtab.empty
blanchet@38937
   631
fun uniquify xs = Termtab.fold (cons o snd) (mk_fact_table snd xs) []
mengj@19768
   632
blanchet@37626
   633
(* FIXME: put other record thms here, or declare as "no_atp" *)
blanchet@37626
   634
val multi_base_blacklist =
blanchet@41199
   635
  ["defs", "select_defs", "update_defs", "split", "splits", "split_asm",
blanchet@41199
   636
   "cases", "ext_cases", "eq.simps", "eq.refl", "nchotomy", "case_cong",
blanchet@41199
   637
   "weak_case_cong"]
blanchet@41273
   638
  |> not instantiate_inducts ? append ["induct", "inducts"]
blanchet@38682
   639
  |> map (prefix ".")
blanchet@37626
   640
blanchet@37626
   641
val max_lambda_nesting = 3
blanchet@37626
   642
blanchet@37626
   643
fun term_has_too_many_lambdas max (t1 $ t2) =
blanchet@37626
   644
    exists (term_has_too_many_lambdas max) [t1, t2]
blanchet@37626
   645
  | term_has_too_many_lambdas max (Abs (_, _, t)) =
blanchet@37626
   646
    max = 0 orelse term_has_too_many_lambdas (max - 1) t
blanchet@37626
   647
  | term_has_too_many_lambdas _ _ = false
blanchet@37626
   648
blanchet@37626
   649
(* Don't count nested lambdas at the level of formulas, since they are
blanchet@37626
   650
   quantifiers. *)
blanchet@37626
   651
fun formula_has_too_many_lambdas Ts (Abs (_, T, t)) =
blanchet@37626
   652
    formula_has_too_many_lambdas (T :: Ts) t
blanchet@37626
   653
  | formula_has_too_many_lambdas Ts t =
blanchet@41273
   654
    if member (op =) [HOLogic.boolT, propT] (fastype_of1 (Ts, t)) then
blanchet@37626
   655
      exists (formula_has_too_many_lambdas Ts) (#2 (strip_comb t))
blanchet@37626
   656
    else
blanchet@37626
   657
      term_has_too_many_lambdas max_lambda_nesting t
blanchet@37626
   658
blanchet@38692
   659
(* The max apply depth of any "metis" call in "Metis_Examples" (on 2007-10-31)
blanchet@37626
   660
   was 11. *)
blanchet@37626
   661
val max_apply_depth = 15
blanchet@37626
   662
blanchet@37626
   663
fun apply_depth (f $ t) = Int.max (apply_depth f, apply_depth t + 1)
blanchet@37626
   664
  | apply_depth (Abs (_, _, t)) = apply_depth t
blanchet@37626
   665
  | apply_depth _ = 0
blanchet@37626
   666
blanchet@37626
   667
fun is_formula_too_complex t =
blanchet@38085
   668
  apply_depth t > max_apply_depth orelse formula_has_too_many_lambdas [] t
blanchet@37626
   669
blanchet@39946
   670
(* FIXME: Extend to "Meson" and "Metis" *)
blanchet@37543
   671
val exists_sledgehammer_const =
blanchet@37626
   672
  exists_Const (fn (s, _) => String.isPrefix sledgehammer_prefix s)
blanchet@37626
   673
blanchet@38904
   674
(* FIXME: make more reliable *)
blanchet@38904
   675
val exists_low_level_class_const =
blanchet@38904
   676
  exists_Const (fn (s, _) =>
blanchet@38904
   677
     String.isSubstring (Long_Name.separator ^ "class" ^ Long_Name.separator) s)
blanchet@38904
   678
blanchet@38821
   679
fun is_metastrange_theorem th =
blanchet@37626
   680
  case head_of (concl_of th) of
blanchet@37626
   681
      Const (a, _) => (a <> @{const_name Trueprop} andalso
blanchet@37626
   682
                       a <> @{const_name "=="})
blanchet@37626
   683
    | _ => false
blanchet@37626
   684
blanchet@38821
   685
fun is_that_fact th =
blanchet@38821
   686
  String.isSuffix (Long_Name.separator ^ Obtain.thatN) (Thm.get_name_hint th)
blanchet@38821
   687
  andalso exists_subterm (fn Free (s, _) => s = Name.skolem Auto_Bind.thesisN
blanchet@38821
   688
                           | _ => false) (prop_of th)
blanchet@38821
   689
blanchet@37626
   690
val type_has_top_sort =
blanchet@37626
   691
  exists_subtype (fn TFree (_, []) => true | TVar (_, []) => true | _ => false)
blanchet@37626
   692
blanchet@38085
   693
(**** Predicates to detect unwanted facts (prolific or likely to cause
blanchet@37347
   694
      unsoundness) ****)
paulson@21470
   695
blanchet@38289
   696
(* Too general means, positive equality literal with a variable X as one
blanchet@38289
   697
   operand, when X does not occur properly in the other operand. This rules out
blanchet@38289
   698
   clearly inconsistent facts such as X = a | X = b, though it by no means
blanchet@38289
   699
   guarantees soundness. *)
paulson@21470
   700
blanchet@38289
   701
(* Unwanted equalities are those between a (bound or schematic) variable that
blanchet@38289
   702
   does not properly occur in the second operand. *)
blanchet@38607
   703
val is_exhaustive_finite =
blanchet@38607
   704
  let
blanchet@38629
   705
    fun is_bad_equal (Var z) t =
blanchet@38629
   706
        not (exists_subterm (fn Var z' => z = z' | _ => false) t)
blanchet@38629
   707
      | is_bad_equal (Bound j) t = not (loose_bvar1 (t, j))
blanchet@38629
   708
      | is_bad_equal _ _ = false
blanchet@38629
   709
    fun do_equals t1 t2 = is_bad_equal t1 t2 orelse is_bad_equal t2 t1
blanchet@38607
   710
    fun do_formula pos t =
blanchet@38607
   711
      case (pos, t) of
blanchet@38615
   712
        (_, @{const Trueprop} $ t1) => do_formula pos t1
blanchet@38607
   713
      | (true, Const (@{const_name all}, _) $ Abs (_, _, t')) =>
blanchet@38607
   714
        do_formula pos t'
blanchet@38607
   715
      | (true, Const (@{const_name All}, _) $ Abs (_, _, t')) =>
blanchet@38607
   716
        do_formula pos t'
blanchet@38607
   717
      | (false, Const (@{const_name Ex}, _) $ Abs (_, _, t')) =>
blanchet@38607
   718
        do_formula pos t'
blanchet@38607
   719
      | (_, @{const "==>"} $ t1 $ t2) =>
blanchet@38629
   720
        do_formula (not pos) t1 andalso
blanchet@38629
   721
        (t2 = @{prop False} orelse do_formula pos t2)
haftmann@38786
   722
      | (_, @{const HOL.implies} $ t1 $ t2) =>
blanchet@38629
   723
        do_formula (not pos) t1 andalso
blanchet@38629
   724
        (t2 = @{const False} orelse do_formula pos t2)
blanchet@38607
   725
      | (_, @{const Not} $ t1) => do_formula (not pos) t1
haftmann@38795
   726
      | (true, @{const HOL.disj} $ t1 $ t2) => forall (do_formula pos) [t1, t2]
haftmann@38795
   727
      | (false, @{const HOL.conj} $ t1 $ t2) => forall (do_formula pos) [t1, t2]
haftmann@38864
   728
      | (true, Const (@{const_name HOL.eq}, _) $ t1 $ t2) => do_equals t1 t2
blanchet@38607
   729
      | (true, Const (@{const_name "=="}, _) $ t1 $ t2) => do_equals t1 t2
blanchet@38607
   730
      | _ => false
blanchet@38607
   731
  in do_formula true end
blanchet@38607
   732
blanchet@38592
   733
fun has_bound_or_var_of_type tycons =
blanchet@38592
   734
  exists_subterm (fn Var (_, Type (s, _)) => member (op =) tycons s
blanchet@38592
   735
                   | Abs (_, Type (s, _), _) => member (op =) tycons s
blanchet@38592
   736
                   | _ => false)
paulson@21431
   737
blanchet@38085
   738
(* Facts are forbidden to contain variables of these types. The typical reason
blanchet@37347
   739
   is that they lead to unsoundness. Note that "unit" satisfies numerous
blanchet@38085
   740
   equations like "?x = ()". The resulting clauses will have no type constraint,
blanchet@37347
   741
   yielding false proofs. Even "bool" leads to many unsound proofs, though only
blanchet@37347
   742
   for higher-order problems. *)
blanchet@38592
   743
val dangerous_types = [@{type_name unit}, @{type_name bool}, @{type_name prop}];
paulson@22217
   744
blanchet@38085
   745
(* Facts containing variables of type "unit" or "bool" or of the form
blanchet@38290
   746
   "ALL x. x = A | x = B | x = C" are likely to lead to unsound proofs if types
blanchet@38290
   747
   are omitted. *)
blanchet@41138
   748
fun is_dangerous_term no_dangerous_types t =
blanchet@41138
   749
  not no_dangerous_types andalso
blanchet@38679
   750
  let val t = transform_elim_term t in
blanchet@38679
   751
    has_bound_or_var_of_type dangerous_types t orelse
blanchet@38679
   752
    is_exhaustive_finite t
blanchet@38679
   753
  end
paulson@21470
   754
blanchet@41138
   755
fun is_theorem_bad_for_atps no_dangerous_types thm =
blanchet@38627
   756
  let val t = prop_of thm in
blanchet@38627
   757
    is_formula_too_complex t orelse exists_type type_has_top_sort t orelse
blanchet@41138
   758
    is_dangerous_term no_dangerous_types t orelse
blanchet@41138
   759
    exists_sledgehammer_const t orelse exists_low_level_class_const t orelse
blanchet@41138
   760
    is_metastrange_theorem thm orelse is_that_fact thm
blanchet@38627
   761
  end
blanchet@38627
   762
blanchet@38937
   763
fun clasimpset_rules_of ctxt =
blanchet@38937
   764
  let
blanchet@38937
   765
    val {safeIs, safeEs, hazIs, hazEs, ...} = ctxt |> claset_of |> rep_cs
blanchet@38937
   766
    val intros = safeIs @ hazIs
blanchet@38937
   767
    val elims = map Classical.classical_rule (safeEs @ hazEs)
blanchet@38937
   768
    val simps = ctxt |> simpset_of |> dest_ss |> #simps |> map snd
blanchet@38937
   769
  in (mk_fact_table I intros, mk_fact_table I elims, mk_fact_table I simps) end
blanchet@38937
   770
blanchet@41138
   771
fun all_facts ctxt reserved no_dangerous_types
blanchet@40205
   772
              ({intro_bonus, elim_bonus, simp_bonus, ...} : relevance_fudge)
blanchet@40205
   773
              add_ths chained_ths =
blanchet@38627
   774
  let
blanchet@38752
   775
    val thy = ProofContext.theory_of ctxt
wenzelm@39557
   776
    val global_facts = Global_Theory.facts_of thy
blanchet@38644
   777
    val local_facts = ProofContext.facts_of ctxt
blanchet@38644
   778
    val named_locals = local_facts |> Facts.dest_static []
blanchet@38993
   779
    val assms = Assumption.all_assms_of ctxt
blanchet@38993
   780
    fun is_assum th = exists (fn ct => prop_of th aconv term_of ct) assms
blanchet@38752
   781
    val is_chained = member Thm.eq_thm chained_ths
blanchet@38937
   782
    val (intros, elims, simps) =
blanchet@40070
   783
      if exists (curry (op <) 0.0) [intro_bonus, elim_bonus, simp_bonus] then
blanchet@38937
   784
        clasimpset_rules_of ctxt
blanchet@38937
   785
      else
blanchet@38937
   786
        (Termtab.empty, Termtab.empty, Termtab.empty)
blanchet@38738
   787
    fun is_good_unnamed_local th =
blanchet@38820
   788
      not (Thm.has_name_hint th) andalso
blanchet@38738
   789
      forall (fn (_, ths) => not (member Thm.eq_thm ths th)) named_locals
blanchet@38644
   790
    val unnamed_locals =
blanchet@38820
   791
      union Thm.eq_thm (Facts.props local_facts) chained_ths
blanchet@38820
   792
      |> filter is_good_unnamed_local |> map (pair "" o single)
blanchet@38627
   793
    val full_space =
blanchet@38738
   794
      Name_Space.merge (Facts.space_of global_facts, Facts.space_of local_facts)
blanchet@38752
   795
    fun add_facts global foldx facts =
blanchet@38699
   796
      foldx (fn (name0, ths) =>
blanchet@38699
   797
        if name0 <> "" andalso
blanchet@39012
   798
           forall (not o member Thm.eq_thm add_ths) ths andalso
blanchet@38699
   799
           (Facts.is_concealed facts name0 orelse
blanchet@38699
   800
            (respect_no_atp andalso is_package_def name0) orelse
blanchet@38699
   801
            exists (fn s => String.isSuffix s name0) multi_base_blacklist orelse
blanchet@38699
   802
            String.isSuffix "_def_raw" (* FIXME: crude hack *) name0) then
blanchet@38627
   803
          I
blanchet@38627
   804
        else
blanchet@38627
   805
          let
blanchet@38699
   806
            val multi = length ths > 1
blanchet@41199
   807
            val backquotify =
blanchet@41199
   808
              enclose "`" "`" o string_for_term ctxt o close_form o prop_of
blanchet@38699
   809
            fun check_thms a =
blanchet@38699
   810
              case try (ProofContext.get_thms ctxt) a of
blanchet@38699
   811
                NONE => false
blanchet@38699
   812
              | SOME ths' => Thm.eq_thms (ths, ths')
blanchet@38627
   813
          in
blanchet@38699
   814
            pair 1
blanchet@38699
   815
            #> fold (fn th => fn (j, rest) =>
blanchet@38699
   816
                 (j + 1,
blanchet@41138
   817
                  if is_theorem_bad_for_atps no_dangerous_types th andalso
blanchet@39012
   818
                     not (member Thm.eq_thm add_ths th) then
blanchet@38699
   819
                    rest
blanchet@38699
   820
                  else
blanchet@38752
   821
                    (((fn () =>
blanchet@38752
   822
                          if name0 = "" then
blanchet@38752
   823
                            th |> backquotify
blanchet@38752
   824
                          else
blanchet@38752
   825
                            let
blanchet@38752
   826
                              val name1 = Facts.extern facts name0
blanchet@38752
   827
                              val name2 = Name_Space.extern full_space name0
blanchet@38752
   828
                            in
blanchet@38752
   829
                              case find_first check_thms [name1, name2, name0] of
blanchet@40375
   830
                                SOME name => make_name reserved multi j name
blanchet@38752
   831
                              | NONE => ""
blanchet@38937
   832
                            end),
blanchet@38937
   833
                      let val t = prop_of th in
blanchet@40071
   834
                        if is_chained th then
blanchet@40071
   835
                          Chained
blanchet@38993
   836
                        else if global then
blanchet@38993
   837
                          if Termtab.defined intros t then Intro
blanchet@38993
   838
                          else if Termtab.defined elims t then Elim
blanchet@38993
   839
                          else if Termtab.defined simps t then Simp
blanchet@38993
   840
                          else General
blanchet@38993
   841
                        else
blanchet@38993
   842
                          if is_assum th then Assum else Local
blanchet@38937
   843
                      end),
blanchet@38752
   844
                      (multi, th)) :: rest)) ths
blanchet@38699
   845
            #> snd
blanchet@38627
   846
          end)
blanchet@38644
   847
  in
blanchet@38752
   848
    [] |> add_facts false fold local_facts (unnamed_locals @ named_locals)
blanchet@38752
   849
       |> add_facts true Facts.fold_static global_facts global_facts
blanchet@38644
   850
  end
blanchet@38627
   851
blanchet@38627
   852
(* The single-name theorems go after the multiple-name ones, so that single
blanchet@38627
   853
   names are preferred when both are available. *)
blanchet@40205
   854
fun rearrange_facts ctxt respect_no_atp =
blanchet@38744
   855
  List.partition (fst o snd) #> op @ #> map (apsnd snd)
blanchet@38699
   856
  #> respect_no_atp ? filter_out (No_ATPs.member ctxt o snd)
blanchet@38627
   857
blanchet@41199
   858
fun external_frees t =
blanchet@41199
   859
  [] |> Term.add_frees t |> filter_out (can Name.dest_internal o fst)
blanchet@41199
   860
blanchet@41138
   861
fun relevant_facts ctxt no_dangerous_types (threshold0, threshold1)
blanchet@41138
   862
                   max_relevant is_built_in_const fudge
blanchet@41138
   863
                   (override as {add, only, ...}) chained_ths hyp_ts concl_t =
blanchet@37538
   864
  let
blanchet@41200
   865
    val thy = ProofContext.theory_of ctxt
blanchet@38822
   866
    val decay = Math.pow ((1.0 - threshold1) / (1.0 - threshold0),
blanchet@38822
   867
                          1.0 / Real.fromInt (max_relevant + 1))
blanchet@39012
   868
    val add_ths = Attrib.eval_thms ctxt add
blanchet@38696
   869
    val reserved = reserved_isar_keyword_table ()
blanchet@41199
   870
    val ind_stmt =
blanchet@41199
   871
      Logic.list_implies (hyp_ts |> filter_out (null o external_frees), concl_t)
blanchet@41211
   872
      |> Object_Logic.atomize_term thy
blanchet@41199
   873
    val ind_stmt_xs = external_frees ind_stmt
blanchet@40204
   874
    val facts =
blanchet@38699
   875
      (if only then
blanchet@38752
   876
         maps (map (fn ((name, loc), th) => ((K name, loc), (true, th)))
blanchet@40205
   877
               o fact_from_ref ctxt reserved chained_ths) add
blanchet@38699
   878
       else
blanchet@41138
   879
         all_facts ctxt reserved no_dangerous_types fudge add_ths chained_ths)
blanchet@41273
   880
      |> instantiate_inducts
blanchet@41273
   881
         ? maps (instantiate_if_induct_rule ctxt ind_stmt ind_stmt_xs)
blanchet@40205
   882
      |> rearrange_facts ctxt (respect_no_atp andalso not only)
blanchet@38937
   883
      |> uniquify
blanchet@37538
   884
  in
blanchet@40204
   885
    trace_msg (fn () => "Considering " ^ Int.toString (length facts) ^
blanchet@40204
   886
                        " facts");
blanchet@39366
   887
    (if only orelse threshold1 < 0.0 then
blanchet@40204
   888
       facts
blanchet@39366
   889
     else if threshold0 > 1.0 orelse threshold0 > threshold1 orelse
blanchet@39366
   890
             max_relevant = 0 then
blanchet@38739
   891
       []
blanchet@38739
   892
     else
blanchet@41200
   893
       ((concl_t |> theory_constify fudge (Context.theory_name thy)) :: hyp_ts)
blanchet@41200
   894
       |> relevance_filter ctxt threshold0 decay max_relevant is_built_in_const
blanchet@41200
   895
                           fudge override facts)
blanchet@38822
   896
    |> map (apfst (apfst (fn f => f ())))
blanchet@37538
   897
  end
immler@30536
   898
paulson@15347
   899
end;