src/HOL/Tools/Sledgehammer/metis_tactics.ML
author blanchet
Thu Apr 29 10:25:26 2010 +0200 (2010-04-29)
changeset 36556 81dc2c20f052
parent 36401 31252c4d4923
child 36909 7d5587f6d5f7
permissions -rw-r--r--
use readable names in "debug" mode for type vars + don't pipe facts using "using" but rather give them directly to metis (works better with type variables)
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(*  Title:      HOL/Tools/Sledgehammer/metis_tactics.ML
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    Author:     Kong W. Susanto and Lawrence C. Paulson, CU Computer Laboratory
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    Copyright   Cambridge University 2007
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HOL setup for the Metis prover.
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*)
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signature METIS_TACTICS =
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sig
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  val trace: bool Unsynchronized.ref
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  val type_lits: bool Config.T
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  val metis_tac: Proof.context -> thm list -> int -> tactic
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  val metisF_tac: Proof.context -> thm list -> int -> tactic
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  val metisFT_tac: Proof.context -> thm list -> int -> tactic
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  val setup: theory -> theory
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end
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structure Metis_Tactics : METIS_TACTICS =
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struct
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open Sledgehammer_FOL_Clause
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open Sledgehammer_Fact_Preprocessor
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open Sledgehammer_HOL_Clause
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open Sledgehammer_Proof_Reconstruct
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open Sledgehammer_Fact_Filter
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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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val (type_lits, type_lits_setup) = Attrib.config_bool "metis_type_lits" (K true);
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datatype mode = FO | HO | FT  (* first-order, higher-order, fully-typed *)
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(* ------------------------------------------------------------------------- *)
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(* Useful Theorems                                                           *)
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(* ------------------------------------------------------------------------- *)
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val EXCLUDED_MIDDLE = @{lemma "P ==> ~ P ==> False" by (rule notE)}
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val REFL_THM = incr_indexes 2 @{lemma "t ~= t ==> False" by simp}
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val subst_em = @{lemma "s = t ==> P s ==> ~ P t ==> False" by simp}
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val ssubst_em = @{lemma "s = t ==> P t ==> ~ P s ==> False" by simp}
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(* ------------------------------------------------------------------------- *)
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(* Useful Functions                                                          *)
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(* ------------------------------------------------------------------------- *)
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(* match untyped terms*)
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fun untyped_aconv (Const(a,_))   (Const(b,_))   = (a=b)
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  | untyped_aconv (Free(a,_))    (Free(b,_))    = (a=b)
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  | untyped_aconv (Var((a,_),_)) (Var((b,_),_)) = (a=b)   (*the index is ignored!*)
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  | untyped_aconv (Bound i)      (Bound j)      = (i=j)
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  | untyped_aconv (Abs(a,_,t))  (Abs(b,_,u))    = (a=b) andalso untyped_aconv t u
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  | untyped_aconv (t1$t2) (u1$u2)  = untyped_aconv t1 u1 andalso untyped_aconv t2 u2
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  | untyped_aconv _              _              = false;
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(* Finding the relative location of an untyped term within a list of terms *)
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fun get_index lit =
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  let val lit = Envir.eta_contract lit
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      fun get n [] = raise Empty
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        | get n (x::xs) = if untyped_aconv lit (Envir.eta_contract (HOLogic.dest_Trueprop x))
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                          then n  else get (n+1) xs
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  in get 1 end;
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(* ------------------------------------------------------------------------- *)
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(* HOL to FOL  (Isabelle to Metis)                                           *)
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(* ------------------------------------------------------------------------- *)
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fun fn_isa_to_met "equal" = "="
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  | fn_isa_to_met x       = x;
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fun metis_lit b c args = (b, (c, args));
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fun hol_type_to_fol (TyVar (x, _)) = Metis.Term.Var x
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  | hol_type_to_fol (TyFree (s, _)) = Metis.Term.Fn (s, [])
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  | hol_type_to_fol (TyConstr ((s, _), tps)) =
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    Metis.Term.Fn (s, map hol_type_to_fol tps);
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(*These two functions insert type literals before the real literals. That is the
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  opposite order from TPTP linkup, but maybe OK.*)
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fun hol_term_to_fol_FO tm =
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  case strip_combterm_comb tm of
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      (CombConst ((c, _), _, tys), tms) =>
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        let val tyargs = map hol_type_to_fol tys
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            val args   = map hol_term_to_fol_FO tms
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        in Metis.Term.Fn (c, tyargs @ args) end
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    | (CombVar ((v, _), _), []) => Metis.Term.Var v
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    | _ => error "hol_term_to_fol_FO";
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fun hol_term_to_fol_HO (CombVar ((s, _), _)) = Metis.Term.Var s
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  | hol_term_to_fol_HO (CombConst ((a, _), _, tylist)) =
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      Metis.Term.Fn (fn_isa_to_met a, map hol_type_to_fol tylist)
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  | hol_term_to_fol_HO (CombApp (tm1, tm2)) =
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       Metis.Term.Fn (".", map hol_term_to_fol_HO [tm1, tm2]);
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(*The fully-typed translation, to avoid type errors*)
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fun wrap_type (tm, ty) = Metis.Term.Fn("ti", [tm, hol_type_to_fol ty]);
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fun hol_term_to_fol_FT (CombVar ((s, _), ty)) = wrap_type (Metis.Term.Var s, ty)
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  | hol_term_to_fol_FT (CombConst((a, _), ty, _)) =
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      wrap_type (Metis.Term.Fn(fn_isa_to_met a, []), ty)
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  | hol_term_to_fol_FT (tm as CombApp(tm1,tm2)) =
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       wrap_type (Metis.Term.Fn(".", map hol_term_to_fol_FT [tm1,tm2]),
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                  type_of_combterm tm);
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fun hol_literal_to_fol FO (Literal (pol, tm)) =
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      let val (CombConst((p, _), _, tys), tms) = strip_combterm_comb tm
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          val tylits = if p = "equal" then [] else map hol_type_to_fol tys
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          val lits = map hol_term_to_fol_FO tms
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      in metis_lit pol (fn_isa_to_met p) (tylits @ lits) end
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  | hol_literal_to_fol HO (Literal (pol, tm)) =
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     (case strip_combterm_comb tm of
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          (CombConst(("equal", _), _, _), tms) =>
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            metis_lit pol "=" (map hol_term_to_fol_HO tms)
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        | _ => metis_lit pol "{}" [hol_term_to_fol_HO tm])   (*hBOOL*)
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  | hol_literal_to_fol FT (Literal (pol, tm)) =
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     (case strip_combterm_comb tm of
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          (CombConst(("equal", _), _, _), tms) =>
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            metis_lit pol "=" (map hol_term_to_fol_FT tms)
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        | _ => metis_lit pol "{}" [hol_term_to_fol_FT tm])   (*hBOOL*);
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fun literals_of_hol_thm thy mode t =
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      let val (lits, types_sorts) = literals_of_term thy t
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      in  (map (hol_literal_to_fol mode) lits, types_sorts) end;
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(*Sign should be "true" for conjecture type constraints, "false" for type lits in clauses.*)
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fun metis_of_type_literals pos (TyLitVar (s, (s', _))) =
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    metis_lit pos s [Metis.Term.Var s']
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  | metis_of_type_literals pos (TyLitFree (s, (s', _))) =
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    metis_lit pos s [Metis.Term.Fn (s',[])]
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fun default_sort _ (TVar _) = false
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  | default_sort ctxt (TFree (x, s)) = (s = the_default [] (Variable.def_sort ctxt (x, ~1)));
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fun metis_of_tfree tf =
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  Metis.Thm.axiom (Metis.LiteralSet.singleton (metis_of_type_literals true tf));
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fun hol_thm_to_fol is_conjecture ctxt mode th =
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  let val thy = ProofContext.theory_of ctxt
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      val (mlits, types_sorts) =
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             (literals_of_hol_thm thy mode o HOLogic.dest_Trueprop o prop_of) th
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  in
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      if is_conjecture then
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          (Metis.Thm.axiom (Metis.LiteralSet.fromList mlits),
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           add_type_literals types_sorts)
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      else
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        let val tylits = add_type_literals (filter (not o default_sort ctxt) types_sorts)
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            val mtylits = if Config.get ctxt type_lits
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                          then map (metis_of_type_literals false) tylits else []
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        in
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          (Metis.Thm.axiom (Metis.LiteralSet.fromList(mtylits @ mlits)), [])
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        end
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  end;
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(* ARITY CLAUSE *)
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fun m_arity_cls (TConsLit (c,t,args)) =
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      metis_lit true (make_type_class c) [Metis.Term.Fn(t, map Metis.Term.Var args)]
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  | m_arity_cls (TVarLit (c,str))     =
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      metis_lit false (make_type_class c) [Metis.Term.Var str];
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(*TrueI is returned as the Isabelle counterpart because there isn't any.*)
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fun arity_cls (ArityClause {conclLit, premLits, ...}) =
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  (TrueI,
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   Metis.Thm.axiom (Metis.LiteralSet.fromList (map m_arity_cls (conclLit :: premLits))));
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(* CLASSREL CLAUSE *)
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fun m_classrel_cls subclass superclass =
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  [metis_lit false subclass [Metis.Term.Var "T"], metis_lit true superclass [Metis.Term.Var "T"]];
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fun classrel_cls (ClassrelClause {subclass, superclass, ...}) =
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  (TrueI, Metis.Thm.axiom (Metis.LiteralSet.fromList (m_classrel_cls subclass superclass)));
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(* ------------------------------------------------------------------------- *)
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(* FOL to HOL  (Metis to Isabelle)                                           *)
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(* ------------------------------------------------------------------------- *)
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datatype term_or_type = Term of Term.term | Type of Term.typ;
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fun terms_of [] = []
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  | terms_of (Term t :: tts) = t :: terms_of tts
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  | terms_of (Type _ :: tts) = terms_of tts;
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fun types_of [] = []
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  | types_of (Term (Term.Var ((a,idx), _)) :: tts) =
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      if String.isPrefix "_" a then
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          (*Variable generated by Metis, which might have been a type variable.*)
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          TVar (("'" ^ a, idx), HOLogic.typeS) :: types_of tts
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      else types_of tts
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  | types_of (Term _ :: tts) = types_of tts
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  | types_of (Type T :: tts) = T :: types_of tts;
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fun apply_list rator nargs rands =
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  let val trands = terms_of rands
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  in  if length trands = nargs then Term (list_comb(rator, trands))
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      else error
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        ("apply_list: wrong number of arguments: " ^ Syntax.string_of_term_global Pure.thy rator ^
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          " expected " ^ Int.toString nargs ^
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          " received " ^ commas (map (Syntax.string_of_term_global Pure.thy) trands))
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  end;
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fun infer_types ctxt =
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  Syntax.check_terms (ProofContext.set_mode ProofContext.mode_pattern ctxt);
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(*We use 1 rather than 0 because variable references in clauses may otherwise conflict
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  with variable constraints in the goal...at least, type inference often fails otherwise.
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  SEE ALSO axiom_inf below.*)
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fun mk_var (w,T) = Term.Var((w,1), T);
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(*include the default sort, if available*)
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fun mk_tfree ctxt w =
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  let val ww = "'" ^ w
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  in  TFree(ww, the_default HOLogic.typeS (Variable.def_sort ctxt (ww, ~1)))  end;
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(*Remove the "apply" operator from an HO term*)
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fun strip_happ args (Metis.Term.Fn(".",[t,u])) = strip_happ (u::args) t
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  | strip_happ args x = (x, args);
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fun fol_type_to_isa _ (Metis.Term.Var v) =
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     (case strip_prefix tvar_prefix v of
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          SOME w => make_tvar w
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        | NONE   => make_tvar v)
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  | fol_type_to_isa ctxt (Metis.Term.Fn(x, tys)) =
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     (case strip_prefix tconst_prefix x of
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          SOME tc => Term.Type (invert_type_const tc, map (fol_type_to_isa ctxt) tys)
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        | NONE    =>
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      case strip_prefix tfree_prefix x of
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          SOME tf => mk_tfree ctxt tf
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        | NONE    => error ("fol_type_to_isa: " ^ x));
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(*Maps metis terms to isabelle terms*)
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fun fol_term_to_hol_RAW ctxt fol_tm =
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  let val thy = ProofContext.theory_of ctxt
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      val _ = trace_msg (fn () => "fol_term_to_hol: " ^ Metis.Term.toString fol_tm)
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      fun tm_to_tt (Metis.Term.Var v) =
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             (case strip_prefix tvar_prefix v of
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                  SOME w => Type (make_tvar w)
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                | NONE =>
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              case strip_prefix schematic_var_prefix v of
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                  SOME w => Term (mk_var (w, HOLogic.typeT))
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                | NONE   => Term (mk_var (v, HOLogic.typeT)) )
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                    (*Var from Metis with a name like _nnn; possibly a type variable*)
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        | tm_to_tt (Metis.Term.Fn ("{}", [arg])) = tm_to_tt arg   (*hBOOL*)
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        | tm_to_tt (t as Metis.Term.Fn (".",_)) =
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            let val (rator,rands) = strip_happ [] t
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            in  case rator of
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                    Metis.Term.Fn(fname,ts) => applic_to_tt (fname, ts @ rands)
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                  | _ => case tm_to_tt rator of
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                             Term t => Term (list_comb(t, terms_of (map tm_to_tt rands)))
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                           | _ => error "tm_to_tt: HO application"
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            end
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        | tm_to_tt (Metis.Term.Fn (fname, args)) = applic_to_tt (fname,args)
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      and applic_to_tt ("=",ts) =
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            Term (list_comb(Const (@{const_name "op ="}, HOLogic.typeT), terms_of (map tm_to_tt ts)))
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        | applic_to_tt (a,ts) =
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            case strip_prefix const_prefix a of
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                SOME b =>
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                  let val c = invert_const b
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                      val ntypes = num_typargs thy c
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                      val nterms = length ts - ntypes
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                      val tts = map tm_to_tt ts
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                      val tys = types_of (List.take(tts,ntypes))
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                      val ntyargs = num_typargs thy c
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                  in if length tys = ntyargs then
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                         apply_list (Const (c, dummyT)) nterms (List.drop(tts,ntypes))
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                     else error ("Constant " ^ c ^ " expects " ^ Int.toString ntyargs ^
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                                 " but gets " ^ Int.toString (length tys) ^
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                                 " type arguments\n" ^
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                                 cat_lines (map (Syntax.string_of_typ ctxt) tys) ^
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                                 " the terms are \n" ^
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                                 cat_lines (map (Syntax.string_of_term ctxt) (terms_of tts)))
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                     end
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              | NONE => (*Not a constant. Is it a type constructor?*)
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            case strip_prefix tconst_prefix a of
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                SOME b =>
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                  Type (Term.Type (invert_type_const b, types_of (map tm_to_tt ts)))
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              | NONE => (*Maybe a TFree. Should then check that ts=[].*)
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            case strip_prefix tfree_prefix a of
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                SOME b => Type (mk_tfree ctxt b)
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              | NONE => (*a fixed variable? They are Skolem functions.*)
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            case strip_prefix fixed_var_prefix a of
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                SOME b =>
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                  let val opr = Term.Free(b, HOLogic.typeT)
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                  in  apply_list opr (length ts) (map tm_to_tt ts)  end
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              | NONE => error ("unexpected metis function: " ^ a)
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  in  case tm_to_tt fol_tm of Term t => t | _ => error "fol_tm_to_tt: Term expected"  end;
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(*Maps fully-typed metis terms to isabelle terms*)
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   289
fun fol_term_to_hol_FT ctxt fol_tm =
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  let val _ = trace_msg (fn () => "fol_term_to_hol_FT: " ^ Metis.Term.toString fol_tm)
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   291
      fun cvt (Metis.Term.Fn ("ti", [Metis.Term.Var v, _])) =
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   292
             (case strip_prefix schematic_var_prefix v of
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                  SOME w =>  mk_var(w, dummyT)
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   294
                | NONE   => mk_var(v, dummyT))
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        | cvt (Metis.Term.Fn ("ti", [Metis.Term.Fn ("=",[]), _])) =
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   296
            Const ("op =", HOLogic.typeT)
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   297
        | cvt (Metis.Term.Fn ("ti", [Metis.Term.Fn (x,[]), ty])) =
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   298
           (case strip_prefix const_prefix x of
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   299
                SOME c => Const (invert_const c, dummyT)
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   300
              | NONE => (*Not a constant. Is it a fixed variable??*)
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   301
            case strip_prefix fixed_var_prefix x of
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   302
                SOME v => Free (v, fol_type_to_isa ctxt ty)
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   303
              | NONE => error ("fol_term_to_hol_FT bad constant: " ^ x))
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   304
        | cvt (Metis.Term.Fn ("ti", [Metis.Term.Fn (".",[tm1,tm2]), _])) =
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   305
            cvt tm1 $ cvt tm2
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   306
        | cvt (Metis.Term.Fn (".",[tm1,tm2])) = (*untyped application*)
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   307
            cvt tm1 $ cvt tm2
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   308
        | cvt (Metis.Term.Fn ("{}", [arg])) = cvt arg   (*hBOOL*)
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   309
        | cvt (Metis.Term.Fn ("=", [tm1,tm2])) =
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   310
            list_comb(Const (@{const_name "op ="}, HOLogic.typeT), map cvt [tm1,tm2])
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   311
        | cvt (t as Metis.Term.Fn (x, [])) =
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   312
           (case strip_prefix const_prefix x of
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   313
                SOME c => Const (invert_const c, dummyT)
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   314
              | NONE => (*Not a constant. Is it a fixed variable??*)
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   315
            case strip_prefix fixed_var_prefix x of
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   316
                SOME v => Free (v, dummyT)
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   317
              | NONE => (trace_msg (fn () => "fol_term_to_hol_FT bad const: " ^ x);
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   318
                  fol_term_to_hol_RAW ctxt t))
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   319
        | cvt t = (trace_msg (fn () => "fol_term_to_hol_FT bad term: " ^ Metis.Term.toString t);
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   320
            fol_term_to_hol_RAW ctxt t)
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   321
  in  cvt fol_tm   end;
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   322
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   323
fun fol_term_to_hol ctxt FO = fol_term_to_hol_RAW ctxt
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   324
  | fol_term_to_hol ctxt HO = fol_term_to_hol_RAW ctxt
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   325
  | fol_term_to_hol ctxt FT = fol_term_to_hol_FT ctxt;
paulson@32532
   326
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   327
fun fol_terms_to_hol ctxt mode fol_tms =
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   328
  let val ts = map (fol_term_to_hol ctxt mode) fol_tms
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   329
      val _ = trace_msg (fn () => "  calling type inference:")
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   330
      val _ = app (fn t => trace_msg (fn () => Syntax.string_of_term ctxt t)) ts
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   331
      val ts' = infer_types ctxt ts;
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   332
      val _ = app (fn t => trace_msg
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   333
                    (fn () => "  final term: " ^ Syntax.string_of_term ctxt t ^
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   334
                              "  of type  " ^ Syntax.string_of_typ ctxt (type_of t)))
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   335
                  ts'
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   336
  in  ts'  end;
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   337
blanchet@35865
   338
fun mk_not (Const (@{const_name Not}, _) $ b) = b
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   339
  | mk_not b = HOLogic.mk_not b;
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   340
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   341
val metis_eq = Metis.Term.Fn ("=", []);
paulson@32532
   342
wenzelm@32956
   343
(* ------------------------------------------------------------------------- *)
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   344
(* FOL step Inference Rules                                                  *)
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   345
(* ------------------------------------------------------------------------- *)
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   346
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   347
(*for debugging only*)
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   348
fun print_thpair (fth,th) =
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   349
  (trace_msg (fn () => "=============================================");
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   350
   trace_msg (fn () => "Metis: " ^ Metis.Thm.toString fth);
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   351
   trace_msg (fn () => "Isabelle: " ^ Display.string_of_thm_without_context th));
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   352
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   353
fun lookth thpairs (fth : Metis.Thm.thm) =
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   354
  the (AList.lookup (uncurry Metis.Thm.equal) thpairs fth)
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   355
  handle Option => error ("Failed to find a Metis theorem " ^ Metis.Thm.toString fth);
wenzelm@23442
   356
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   357
fun is_TrueI th = Thm.eq_thm(TrueI,th);
wenzelm@23442
   358
wenzelm@32956
   359
fun cterm_incr_types thy idx = cterm_of thy o (map_types (Logic.incr_tvar idx));
paulson@24974
   360
wenzelm@32956
   361
fun inst_excluded_middle thy i_atm =
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   362
  let val th = EXCLUDED_MIDDLE
wenzelm@32956
   363
      val [vx] = Term.add_vars (prop_of th) []
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   364
      val substs = [(cterm_of thy (Var vx), cterm_of thy i_atm)]
wenzelm@32956
   365
  in  cterm_instantiate substs th  end;
wenzelm@23442
   366
wenzelm@32956
   367
(* INFERENCE RULE: AXIOM *)
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   368
fun axiom_inf thpairs th = incr_indexes 1 (lookth thpairs th);
wenzelm@32956
   369
    (*This causes variables to have an index of 1 by default. SEE ALSO mk_var above.*)
wenzelm@23442
   370
wenzelm@32956
   371
(* INFERENCE RULE: ASSUME *)
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   372
fun assume_inf ctxt mode atm =
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   373
  inst_excluded_middle
wenzelm@32956
   374
    (ProofContext.theory_of ctxt)
wenzelm@32956
   375
    (singleton (fol_terms_to_hol ctxt mode) (Metis.Term.Fn atm));
wenzelm@23442
   376
wenzelm@32956
   377
(* INFERENCE RULE: INSTANTIATE (Subst). Type instantiations are ignored. Trying to reconstruct
wenzelm@32956
   378
   them admits new possibilities of errors, e.g. concerning sorts. Instead we try to arrange
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   379
   that new TVars are distinct and that types can be inferred from terms.*)
wenzelm@32956
   380
fun inst_inf ctxt mode thpairs fsubst th =
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   381
  let val thy = ProofContext.theory_of ctxt
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   382
      val i_th   = lookth thpairs th
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   383
      val i_th_vars = Term.add_vars (prop_of i_th) []
wenzelm@33035
   384
      fun find_var x = the (List.find (fn ((a,_),_) => a=x) i_th_vars)
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   385
      fun subst_translation (x,y) =
wenzelm@32956
   386
            let val v = find_var x
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   387
                val t = fol_term_to_hol ctxt mode y (*we call infer_types below*)
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   388
            in  SOME (cterm_of thy (Var v), t)  end
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   389
            handle Option =>
wenzelm@32956
   390
                (trace_msg (fn() => "List.find failed for the variable " ^ x ^
wenzelm@32956
   391
                                       " in " ^ Display.string_of_thm ctxt i_th);
wenzelm@32956
   392
                 NONE)
wenzelm@32956
   393
      fun remove_typeinst (a, t) =
blanchet@35865
   394
            case strip_prefix schematic_var_prefix a of
wenzelm@32956
   395
                SOME b => SOME (b, t)
blanchet@35865
   396
              | NONE   => case strip_prefix tvar_prefix a of
wenzelm@32956
   397
                SOME _ => NONE          (*type instantiations are forbidden!*)
wenzelm@32956
   398
              | NONE   => SOME (a,t)    (*internal Metis var?*)
wenzelm@32956
   399
      val _ = trace_msg (fn () => "  isa th: " ^ Display.string_of_thm ctxt i_th)
wenzelm@32956
   400
      val substs = map_filter remove_typeinst (Metis.Subst.toList fsubst)
wenzelm@32956
   401
      val (vars,rawtms) = ListPair.unzip (map_filter subst_translation substs)
wenzelm@32956
   402
      val tms = infer_types ctxt rawtms;
wenzelm@32956
   403
      val ctm_of = cterm_incr_types thy (1 + Thm.maxidx_of i_th)
wenzelm@32956
   404
      val substs' = ListPair.zip (vars, map ctm_of tms)
wenzelm@32956
   405
      val _ = trace_msg (fn () =>
wenzelm@32956
   406
        cat_lines ("subst_translations:" ::
wenzelm@32956
   407
          (substs' |> map (fn (x, y) =>
wenzelm@32956
   408
            Syntax.string_of_term ctxt (term_of x) ^ " |-> " ^
wenzelm@32956
   409
            Syntax.string_of_term ctxt (term_of y)))));
wenzelm@32956
   410
  in  cterm_instantiate substs' i_th
wenzelm@32956
   411
      handle THM (msg, _, _) => error ("metis error (inst_inf): " ^ msg)
wenzelm@32956
   412
  end;
wenzelm@23442
   413
wenzelm@32956
   414
(* INFERENCE RULE: RESOLVE *)
wenzelm@25713
   415
wenzelm@32956
   416
(*Like RSN, but we rename apart only the type variables. Vars here typically have an index
wenzelm@32956
   417
  of 1, and the use of RSN would increase this typically to 3. Instantiations of those Vars
wenzelm@32956
   418
  could then fail. See comment on mk_var.*)
wenzelm@32956
   419
fun resolve_inc_tyvars(tha,i,thb) =
wenzelm@32956
   420
  let val tha = Drule.incr_type_indexes (1 + Thm.maxidx_of thb) tha
wenzelm@32956
   421
      val ths = Seq.list_of (Thm.bicompose false (false,tha,nprems_of tha) i thb)
wenzelm@32956
   422
  in
wenzelm@32956
   423
      case distinct Thm.eq_thm ths of
wenzelm@32956
   424
        [th] => th
wenzelm@32956
   425
      | _ => raise THM ("resolve_inc_tyvars: unique result expected", i, [tha,thb])
wenzelm@32956
   426
  end;
wenzelm@23442
   427
wenzelm@32956
   428
fun resolve_inf ctxt mode thpairs atm th1 th2 =
wenzelm@32956
   429
  let
wenzelm@32956
   430
    val i_th1 = lookth thpairs th1 and i_th2 = lookth thpairs th2
wenzelm@32956
   431
    val _ = trace_msg (fn () => "  isa th1 (pos): " ^ Display.string_of_thm ctxt i_th1)
wenzelm@32956
   432
    val _ = trace_msg (fn () => "  isa th2 (neg): " ^ Display.string_of_thm ctxt i_th2)
wenzelm@32956
   433
  in
wenzelm@32956
   434
    if is_TrueI i_th1 then i_th2 (*Trivial cases where one operand is type info*)
wenzelm@32956
   435
    else if is_TrueI i_th2 then i_th1
wenzelm@32956
   436
    else
wenzelm@32956
   437
      let
wenzelm@32956
   438
        val i_atm = singleton (fol_terms_to_hol ctxt mode) (Metis.Term.Fn atm)
wenzelm@32956
   439
        val _ = trace_msg (fn () => "  atom: " ^ Syntax.string_of_term ctxt i_atm)
wenzelm@32956
   440
        val prems_th1 = prems_of i_th1
wenzelm@32956
   441
        val prems_th2 = prems_of i_th2
wenzelm@32956
   442
        val index_th1 = get_index (mk_not i_atm) prems_th1
wenzelm@32956
   443
              handle Empty => error "Failed to find literal in th1"
wenzelm@32956
   444
        val _ = trace_msg (fn () => "  index_th1: " ^ Int.toString index_th1)
wenzelm@32956
   445
        val index_th2 = get_index i_atm prems_th2
wenzelm@32956
   446
              handle Empty => error "Failed to find literal in th2"
wenzelm@32956
   447
        val _ = trace_msg (fn () => "  index_th2: " ^ Int.toString index_th2)
wenzelm@32956
   448
    in  resolve_inc_tyvars (Meson.select_literal index_th1 i_th1, index_th2, i_th2)  end
wenzelm@32956
   449
  end;
wenzelm@23442
   450
wenzelm@32956
   451
(* INFERENCE RULE: REFL *)
wenzelm@32956
   452
val refl_x = cterm_of @{theory} (Var (hd (Term.add_vars (prop_of REFL_THM) [])));
wenzelm@32956
   453
val refl_idx = 1 + Thm.maxidx_of REFL_THM;
wenzelm@25713
   454
wenzelm@32956
   455
fun refl_inf ctxt mode t =
wenzelm@32956
   456
  let val thy = ProofContext.theory_of ctxt
wenzelm@32956
   457
      val i_t = singleton (fol_terms_to_hol ctxt mode) t
wenzelm@32956
   458
      val _ = trace_msg (fn () => "  term: " ^ Syntax.string_of_term ctxt i_t)
wenzelm@32956
   459
      val c_t = cterm_incr_types thy refl_idx i_t
wenzelm@32956
   460
  in  cterm_instantiate [(refl_x, c_t)] REFL_THM  end;
wenzelm@23442
   461
blanchet@35865
   462
fun get_ty_arg_size _ (Const (@{const_name "op ="}, _)) = 0  (*equality has no type arguments*)
blanchet@35865
   463
  | get_ty_arg_size thy (Const (c, _)) = (num_typargs thy c handle TYPE _ => 0)
wenzelm@32994
   464
  | get_ty_arg_size _ _ = 0;
wenzelm@23442
   465
wenzelm@32956
   466
(* INFERENCE RULE: EQUALITY *)
wenzelm@32994
   467
fun equality_inf ctxt mode (pos, atm) fp fr =
wenzelm@32956
   468
  let val thy = ProofContext.theory_of ctxt
wenzelm@32956
   469
      val m_tm = Metis.Term.Fn atm
wenzelm@32956
   470
      val [i_atm,i_tm] = fol_terms_to_hol ctxt mode [m_tm, fr]
wenzelm@32956
   471
      val _ = trace_msg (fn () => "sign of the literal: " ^ Bool.toString pos)
wenzelm@32994
   472
      fun replace_item_list lx 0 (_::ls) = lx::ls
wenzelm@32956
   473
        | replace_item_list lx i (l::ls) = l :: replace_item_list lx (i-1) ls
wenzelm@32956
   474
      fun path_finder_FO tm [] = (tm, Term.Bound 0)
wenzelm@32956
   475
        | path_finder_FO tm (p::ps) =
blanchet@35865
   476
            let val (tm1,args) = strip_comb tm
wenzelm@32956
   477
                val adjustment = get_ty_arg_size thy tm1
wenzelm@32956
   478
                val p' = if adjustment > p then p else p-adjustment
wenzelm@32956
   479
                val tm_p = List.nth(args,p')
wenzelm@32956
   480
                  handle Subscript => error ("equality_inf: " ^ Int.toString p ^ " adj " ^
wenzelm@32956
   481
                    Int.toString adjustment  ^ " term " ^  Syntax.string_of_term ctxt tm)
wenzelm@32956
   482
                val _ = trace_msg (fn () => "path_finder: " ^ Int.toString p ^
wenzelm@32956
   483
                                      "  " ^ Syntax.string_of_term ctxt tm_p)
wenzelm@32956
   484
                val (r,t) = path_finder_FO tm_p ps
wenzelm@32956
   485
            in
wenzelm@32956
   486
                (r, list_comb (tm1, replace_item_list t p' args))
wenzelm@32956
   487
            end
wenzelm@32956
   488
      fun path_finder_HO tm [] = (tm, Term.Bound 0)
wenzelm@32956
   489
        | path_finder_HO (t$u) (0::ps) = (fn(x,y) => (x, y$u)) (path_finder_HO t ps)
wenzelm@32994
   490
        | path_finder_HO (t$u) (_::ps) = (fn(x,y) => (x, t$y)) (path_finder_HO u ps)
wenzelm@32956
   491
      fun path_finder_FT tm [] _ = (tm, Term.Bound 0)
wenzelm@32994
   492
        | path_finder_FT tm (0::ps) (Metis.Term.Fn ("ti", [t1, _])) =
wenzelm@32956
   493
            path_finder_FT tm ps t1
wenzelm@32994
   494
        | path_finder_FT (t$u) (0::ps) (Metis.Term.Fn (".", [t1, _])) =
wenzelm@32956
   495
            (fn(x,y) => (x, y$u)) (path_finder_FT t ps t1)
wenzelm@32994
   496
        | path_finder_FT (t$u) (1::ps) (Metis.Term.Fn (".", [_, t2])) =
wenzelm@32956
   497
            (fn(x,y) => (x, t$y)) (path_finder_FT u ps t2)
wenzelm@32956
   498
        | path_finder_FT tm ps t = error ("equality_inf, path_finder_FT: path = " ^
wenzelm@32956
   499
                                        space_implode " " (map Int.toString ps) ^
wenzelm@32956
   500
                                        " isa-term: " ^  Syntax.string_of_term ctxt tm ^
wenzelm@32956
   501
                                        " fol-term: " ^ Metis.Term.toString t)
wenzelm@32956
   502
      fun path_finder FO tm ps _ = path_finder_FO tm ps
blanchet@35865
   503
        | path_finder HO (tm as Const(@{const_name "op ="},_) $ _ $ _) (p::ps) _ =
wenzelm@32956
   504
             (*equality: not curried, as other predicates are*)
wenzelm@32956
   505
             if p=0 then path_finder_HO tm (0::1::ps)  (*select first operand*)
wenzelm@32956
   506
             else path_finder_HO tm (p::ps)        (*1 selects second operand*)
wenzelm@32994
   507
        | path_finder HO tm (_ :: ps) (Metis.Term.Fn ("{}", [_])) =
wenzelm@32956
   508
             path_finder_HO tm ps      (*if not equality, ignore head to skip hBOOL*)
blanchet@35865
   509
        | path_finder FT (tm as Const(@{const_name "op ="}, _) $ _ $ _) (p::ps)
wenzelm@32956
   510
                            (Metis.Term.Fn ("=", [t1,t2])) =
wenzelm@32956
   511
             (*equality: not curried, as other predicates are*)
wenzelm@32956
   512
             if p=0 then path_finder_FT tm (0::1::ps)
wenzelm@32956
   513
                          (Metis.Term.Fn (".", [Metis.Term.Fn (".", [metis_eq,t1]), t2]))
wenzelm@32956
   514
                          (*select first operand*)
wenzelm@32956
   515
             else path_finder_FT tm (p::ps)
wenzelm@32956
   516
                   (Metis.Term.Fn (".", [metis_eq,t2]))
wenzelm@32956
   517
                   (*1 selects second operand*)
wenzelm@32994
   518
        | path_finder FT tm (_ :: ps) (Metis.Term.Fn ("{}", [t1])) = path_finder_FT tm ps t1
wenzelm@32956
   519
             (*if not equality, ignore head to skip the hBOOL predicate*)
wenzelm@32956
   520
        | path_finder FT tm ps t = path_finder_FT tm ps t  (*really an error case!*)
blanchet@35865
   521
      fun path_finder_lit ((nt as Const (@{const_name Not}, _)) $ tm_a) idx =
wenzelm@32956
   522
            let val (tm, tm_rslt) = path_finder mode tm_a idx m_tm
wenzelm@32956
   523
            in (tm, nt $ tm_rslt) end
wenzelm@32956
   524
        | path_finder_lit tm_a idx = path_finder mode tm_a idx m_tm
wenzelm@32956
   525
      val (tm_subst, body) = path_finder_lit i_atm fp
wenzelm@32956
   526
      val tm_abs = Term.Abs("x", Term.type_of tm_subst, body)
wenzelm@32956
   527
      val _ = trace_msg (fn () => "abstraction: " ^ Syntax.string_of_term ctxt tm_abs)
wenzelm@32956
   528
      val _ = trace_msg (fn () => "i_tm: " ^ Syntax.string_of_term ctxt i_tm)
wenzelm@32956
   529
      val _ = trace_msg (fn () => "located term: " ^ Syntax.string_of_term ctxt tm_subst)
wenzelm@32956
   530
      val imax = maxidx_of_term (i_tm $ tm_abs $ tm_subst)  (*ill typed but gives right max*)
wenzelm@32956
   531
      val subst' = incr_indexes (imax+1) (if pos then subst_em else ssubst_em)
wenzelm@32956
   532
      val _ = trace_msg (fn () => "subst' " ^ Display.string_of_thm ctxt subst')
wenzelm@32956
   533
      val eq_terms = map (pairself (cterm_of thy))
wenzelm@33227
   534
        (ListPair.zip (OldTerm.term_vars (prop_of subst'), [tm_abs, tm_subst, i_tm]))
wenzelm@32956
   535
  in  cterm_instantiate eq_terms subst'  end;
wenzelm@23442
   536
wenzelm@32956
   537
val factor = Seq.hd o distinct_subgoals_tac;
paulson@28528
   538
wenzelm@32994
   539
fun step _ _ thpairs (fol_th, Metis.Proof.Axiom _) = factor (axiom_inf thpairs fol_th)
wenzelm@32994
   540
  | step ctxt mode _ (_, Metis.Proof.Assume f_atm) = assume_inf ctxt mode f_atm
wenzelm@32994
   541
  | step ctxt mode thpairs (_, Metis.Proof.Subst (f_subst, f_th1)) =
wenzelm@32956
   542
      factor (inst_inf ctxt mode thpairs f_subst f_th1)
wenzelm@32994
   543
  | step ctxt mode thpairs (_, Metis.Proof.Resolve(f_atm, f_th1, f_th2)) =
wenzelm@32956
   544
      factor (resolve_inf ctxt mode thpairs f_atm f_th1 f_th2)
wenzelm@32994
   545
  | step ctxt mode _ (_, Metis.Proof.Refl f_tm) = refl_inf ctxt mode f_tm
wenzelm@32994
   546
  | step ctxt mode _ (_, Metis.Proof.Equality (f_lit, f_p, f_r)) =
wenzelm@32994
   547
      equality_inf ctxt mode f_lit f_p f_r;
wenzelm@23442
   548
blanchet@35865
   549
fun real_literal (_, (c, _)) = not (String.isPrefix class_prefix c);
wenzelm@23442
   550
wenzelm@32994
   551
fun translate _ _ thpairs [] = thpairs
wenzelm@32956
   552
  | translate mode ctxt thpairs ((fol_th, inf) :: infpairs) =
wenzelm@32956
   553
      let val _ = trace_msg (fn () => "=============================================")
wenzelm@32956
   554
          val _ = trace_msg (fn () => "METIS THM: " ^ Metis.Thm.toString fol_th)
wenzelm@32956
   555
          val _ = trace_msg (fn () => "INFERENCE: " ^ Metis.Proof.inferenceToString inf)
wenzelm@32956
   556
          val th = Meson.flexflex_first_order (step ctxt mode thpairs (fol_th, inf))
wenzelm@32956
   557
          val _ = trace_msg (fn () => "ISABELLE THM: " ^ Display.string_of_thm ctxt th)
wenzelm@32956
   558
          val _ = trace_msg (fn () => "=============================================")
wenzelm@32994
   559
          val n_metis_lits =
wenzelm@32994
   560
            length (filter real_literal (Metis.LiteralSet.toList (Metis.Thm.clause fol_th)))
wenzelm@32956
   561
      in
wenzelm@32956
   562
          if nprems_of th = n_metis_lits then ()
wenzelm@32956
   563
          else error "Metis: proof reconstruction has gone wrong";
wenzelm@32956
   564
          translate mode ctxt ((fol_th, th) :: thpairs) infpairs
wenzelm@32956
   565
      end;
wenzelm@23442
   566
wenzelm@32956
   567
(*Determining which axiom clauses are actually used*)
wenzelm@32956
   568
fun used_axioms axioms (th, Metis.Proof.Axiom _) = SOME (lookth axioms th)
wenzelm@32994
   569
  | used_axioms _ _ = NONE;
paulson@24855
   570
wenzelm@32956
   571
(* ------------------------------------------------------------------------- *)
wenzelm@32956
   572
(* Translation of HO Clauses                                                 *)
wenzelm@32956
   573
(* ------------------------------------------------------------------------- *)
wenzelm@23442
   574
blanchet@35865
   575
fun cnf_th thy th = hd (cnf_axiom thy th);
wenzelm@23442
   576
wenzelm@32956
   577
fun type_ext thy tms =
blanchet@35865
   578
  let val subs = tfree_classes_of_terms tms
blanchet@35865
   579
      val supers = tvar_classes_of_terms tms
blanchet@35865
   580
      and tycons = type_consts_of_terms thy tms
blanchet@35865
   581
      val (supers', arity_clauses) = make_arity_clauses thy tycons supers
blanchet@35865
   582
      val classrel_clauses = make_classrel_clauses thy subs supers'
wenzelm@32956
   583
  in  map classrel_cls classrel_clauses @ map arity_cls arity_clauses
wenzelm@32956
   584
  end;
wenzelm@23442
   585
wenzelm@32956
   586
(* ------------------------------------------------------------------------- *)
wenzelm@32956
   587
(* Logic maps manage the interface between HOL and first-order logic.        *)
wenzelm@32956
   588
(* ------------------------------------------------------------------------- *)
wenzelm@23442
   589
wenzelm@32956
   590
type logic_map =
blanchet@35865
   591
  {axioms: (Metis.Thm.thm * thm) list,
blanchet@35865
   592
   tfrees: type_literal list};
wenzelm@23442
   593
wenzelm@32994
   594
fun const_in_metis c (pred, tm_list) =
wenzelm@32956
   595
  let
wenzelm@32994
   596
    fun in_mterm (Metis.Term.Var _) = false
wenzelm@32956
   597
      | in_mterm (Metis.Term.Fn (".", tm_list)) = exists in_mterm tm_list
wenzelm@32956
   598
      | in_mterm (Metis.Term.Fn (nm, tm_list)) = c=nm orelse exists in_mterm tm_list
wenzelm@32994
   599
  in  c = pred orelse exists in_mterm tm_list  end;
wenzelm@23442
   600
wenzelm@32956
   601
(*Extract TFree constraints from context to include as conjecture clauses*)
wenzelm@32956
   602
fun init_tfrees ctxt =
wenzelm@32956
   603
  let fun add ((a,i),s) Ts = if i = ~1 then TFree(a,s) :: Ts else Ts
blanchet@36556
   604
  in
blanchet@36556
   605
    add_type_literals (Vartab.fold add (#2 (Variable.constraints_of ctxt)) [])
blanchet@36556
   606
  end;
paulson@24937
   607
wenzelm@32956
   608
(*transform isabelle type / arity clause to metis clause *)
wenzelm@32956
   609
fun add_type_thm [] lmap = lmap
wenzelm@32956
   610
  | add_type_thm ((ith, mth) :: cls) {axioms, tfrees} =
wenzelm@32956
   611
      add_type_thm cls {axioms = (mth, ith) :: axioms,
wenzelm@32956
   612
                        tfrees = tfrees}
wenzelm@23442
   613
wenzelm@32956
   614
(*Insert non-logical axioms corresponding to all accumulated TFrees*)
wenzelm@32956
   615
fun add_tfrees {axioms, tfrees} : logic_map =
wenzelm@32956
   616
     {axioms = (map (fn tf => (metis_of_tfree tf, TrueI)) (distinct op= tfrees)) @ axioms,
wenzelm@32956
   617
      tfrees = tfrees};
wenzelm@25713
   618
wenzelm@32956
   619
fun string_of_mode FO = "FO"
wenzelm@32956
   620
  | string_of_mode HO = "HO"
wenzelm@32956
   621
  | string_of_mode FT = "FT"
paulson@32532
   622
wenzelm@32956
   623
(* Function to generate metis clauses, including comb and type clauses *)
wenzelm@32956
   624
fun build_map mode0 ctxt cls ths =
wenzelm@32956
   625
  let val thy = ProofContext.theory_of ctxt
wenzelm@32956
   626
      (*The modes FO and FT are sticky. HO can be downgraded to FO.*)
wenzelm@32956
   627
      fun set_mode FO = FO
wenzelm@32956
   628
        | set_mode HO = if forall (Meson.is_fol_term thy o prop_of) (cls@ths) then FO else HO
wenzelm@32956
   629
        | set_mode FT = FT
wenzelm@32956
   630
      val mode = set_mode mode0
wenzelm@32956
   631
      (*transform isabelle clause to metis clause *)
wenzelm@33339
   632
      fun add_thm is_conjecture ith {axioms, tfrees} : logic_map =
wenzelm@32956
   633
        let val (mth, tfree_lits) = hol_thm_to_fol is_conjecture ctxt mode ith
wenzelm@32956
   634
        in
wenzelm@32956
   635
           {axioms = (mth, Meson.make_meta_clause ith) :: axioms,
haftmann@33042
   636
            tfrees = union (op =) tfree_lits tfrees}
wenzelm@32956
   637
        end;
wenzelm@33339
   638
      val lmap0 = fold (add_thm true) cls {axioms = [], tfrees = init_tfrees ctxt}
wenzelm@33339
   639
      val lmap = fold (add_thm false) ths (add_tfrees lmap0)
wenzelm@32956
   640
      val clause_lists = map (Metis.Thm.clause o #1) (#axioms lmap)
wenzelm@32994
   641
      fun used c = exists (Metis.LiteralSet.exists (const_in_metis c o #2)) clause_lists
wenzelm@32956
   642
      (*Now check for the existence of certain combinators*)
blanchet@35865
   643
      val thI  = if used "c_COMBI" then [cnf_th @{theory} @{thm COMBI_def}] else []
blanchet@35865
   644
      val thK  = if used "c_COMBK" then [cnf_th @{theory} @{thm COMBK_def}] else []
blanchet@35865
   645
      val thB   = if used "c_COMBB" then [cnf_th @{theory} @{thm COMBB_def}] else []
blanchet@35865
   646
      val thC   = if used "c_COMBC" then [cnf_th @{theory} @{thm COMBC_def}] else []
blanchet@35865
   647
      val thS   = if used "c_COMBS" then [cnf_th @{theory} @{thm COMBS_def}] else []
blanchet@35865
   648
      val thEQ  = if used "c_fequal" then [cnf_th @{theory} @{thm fequal_imp_equal}, cnf_th @{theory} @{thm equal_imp_fequal}] else []
wenzelm@32956
   649
      val lmap' = if mode=FO then lmap
wenzelm@33339
   650
                  else fold (add_thm false) (thEQ @ thS @ thC @ thB @ thK @ thI) lmap
wenzelm@32956
   651
  in
wenzelm@32956
   652
      (mode, add_type_thm (type_ext thy (map prop_of (cls @ ths))) lmap')
wenzelm@32956
   653
  end;
wenzelm@23442
   654
wenzelm@32956
   655
fun refute cls =
wenzelm@32956
   656
    Metis.Resolution.loop (Metis.Resolution.new Metis.Resolution.default cls);
wenzelm@23442
   657
wenzelm@32956
   658
fun is_false t = t aconv (HOLogic.mk_Trueprop HOLogic.false_const);
wenzelm@23442
   659
wenzelm@32956
   660
fun common_thm ths1 ths2 = exists (member Thm.eq_thm ths1) (map Meson.make_meta_clause ths2);
paulson@24855
   661
wenzelm@32956
   662
exception METIS of string;
paulson@28233
   663
wenzelm@32956
   664
(* Main function to start metis prove and reconstruction *)
wenzelm@32956
   665
fun FOL_SOLVE mode ctxt cls ths0 =
wenzelm@32956
   666
  let val thy = ProofContext.theory_of ctxt
blanchet@35826
   667
      val th_cls_pairs =
blanchet@35865
   668
        map (fn th => (Thm.get_name_hint th, cnf_axiom thy th)) ths0
wenzelm@32956
   669
      val ths = maps #2 th_cls_pairs
wenzelm@32956
   670
      val _ = trace_msg (fn () => "FOL_SOLVE: CONJECTURE CLAUSES")
wenzelm@32956
   671
      val _ = app (fn th => trace_msg (fn () => Display.string_of_thm ctxt th)) cls
wenzelm@32956
   672
      val _ = trace_msg (fn () => "THEOREM CLAUSES")
wenzelm@32956
   673
      val _ = app (fn th => trace_msg (fn () => Display.string_of_thm ctxt th)) ths
wenzelm@32956
   674
      val (mode, {axioms,tfrees}) = build_map mode ctxt cls ths
wenzelm@32956
   675
      val _ = if null tfrees then ()
wenzelm@32956
   676
              else (trace_msg (fn () => "TFREE CLAUSES");
blanchet@36556
   677
                    app (fn tf => trace_msg (fn _ => tptp_of_type_literal true tf NONE |> fst)) tfrees)
wenzelm@32956
   678
      val _ = trace_msg (fn () => "CLAUSES GIVEN TO METIS")
wenzelm@32956
   679
      val thms = map #1 axioms
wenzelm@32956
   680
      val _ = app (fn th => trace_msg (fn () => Metis.Thm.toString th)) thms
wenzelm@32956
   681
      val _ = trace_msg (fn () => "mode = " ^ string_of_mode mode)
wenzelm@32956
   682
      val _ = trace_msg (fn () => "START METIS PROVE PROCESS")
wenzelm@32956
   683
  in
wenzelm@33317
   684
      case filter (is_false o prop_of) cls of
wenzelm@32956
   685
          false_th::_ => [false_th RS @{thm FalseE}]
wenzelm@32956
   686
        | [] =>
wenzelm@32956
   687
      case refute thms of
wenzelm@32956
   688
          Metis.Resolution.Contradiction mth =>
wenzelm@32956
   689
            let val _ = trace_msg (fn () => "METIS RECONSTRUCTION START: " ^
wenzelm@32956
   690
                          Metis.Thm.toString mth)
wenzelm@32956
   691
                val ctxt' = fold Variable.declare_constraints (map prop_of cls) ctxt
wenzelm@32956
   692
                             (*add constraints arising from converting goal to clause form*)
wenzelm@32956
   693
                val proof = Metis.Proof.proof mth
wenzelm@32956
   694
                val result = translate mode ctxt' axioms proof
wenzelm@32956
   695
                and used = map_filter (used_axioms axioms) proof
wenzelm@32956
   696
                val _ = trace_msg (fn () => "METIS COMPLETED...clauses actually used:")
wenzelm@32956
   697
                val _ = app (fn th => trace_msg (fn () => Display.string_of_thm ctxt th)) used
wenzelm@33305
   698
                val unused = th_cls_pairs |> map_filter (fn (name, cls) =>
wenzelm@33305
   699
                  if common_thm used cls then NONE else SOME name)
wenzelm@32956
   700
            in
blanchet@36383
   701
                if not (null cls) andalso not (common_thm used cls) then
blanchet@36383
   702
                  warning "Metis: The assumptions are inconsistent."
blanchet@36383
   703
                else
blanchet@36383
   704
                  ();
blanchet@36383
   705
                if not (null unused) then
blanchet@36230
   706
                  warning ("Metis: Unused theorems: " ^ commas_quote unused
blanchet@36230
   707
                           ^ ".")
blanchet@36230
   708
                else
blanchet@36230
   709
                  ();
wenzelm@32956
   710
                case result of
wenzelm@32956
   711
                    (_,ith)::_ =>
blanchet@36230
   712
                        (trace_msg (fn () => "Success: " ^ Display.string_of_thm ctxt ith);
wenzelm@32956
   713
                         [ith])
blanchet@36230
   714
                  | _ => (trace_msg (fn () => "Metis: No result");
wenzelm@32956
   715
                          [])
wenzelm@32956
   716
            end
wenzelm@32956
   717
        | Metis.Resolution.Satisfiable _ =>
wenzelm@32956
   718
            (trace_msg (fn () => "Metis: No first-order proof with the lemmas supplied");
wenzelm@32956
   719
             [])
wenzelm@32956
   720
  end;
wenzelm@23442
   721
wenzelm@32956
   722
fun metis_general_tac mode ctxt ths i st0 =
wenzelm@32956
   723
  let val _ = trace_msg (fn () =>
wenzelm@32956
   724
        "Metis called with theorems " ^ cat_lines (map (Display.string_of_thm ctxt) ths))
wenzelm@32956
   725
  in
blanchet@35865
   726
    if exists_type type_has_topsort (prop_of st0)
wenzelm@35568
   727
    then raise METIS "Metis: Proof state contains the universal sort {}"
wenzelm@35568
   728
    else
blanchet@36401
   729
      (Meson.MESON (maps neg_clausify)
wenzelm@35568
   730
        (fn cls => resolve_tac (FOL_SOLVE mode ctxt cls ths) 1) ctxt i
blanchet@35865
   731
          THEN Meson_Tactic.expand_defs_tac st0) st0
wenzelm@32956
   732
  end
wenzelm@32956
   733
  handle METIS s => (warning ("Metis: " ^ s); Seq.empty);
wenzelm@23442
   734
wenzelm@32956
   735
val metis_tac = metis_general_tac HO;
wenzelm@32956
   736
val metisF_tac = metis_general_tac FO;
wenzelm@32956
   737
val metisFT_tac = metis_general_tac FT;
wenzelm@23442
   738
wenzelm@32956
   739
fun method name mode comment = Method.setup name (Attrib.thms >> (fn ths => fn ctxt =>
wenzelm@32956
   740
  SIMPLE_METHOD' (CHANGED_PROP o metis_general_tac mode ctxt ths))) comment;
wenzelm@23442
   741
wenzelm@32956
   742
val setup =
wenzelm@32956
   743
  type_lits_setup #>
blanchet@35865
   744
  method @{binding metis} HO "METIS for FOL and HOL problems" #>
wenzelm@32956
   745
  method @{binding metisF} FO "METIS for FOL problems" #>
wenzelm@35568
   746
  method @{binding metisFT} FT "METIS with fully-typed translation" #>
wenzelm@32956
   747
  Method.setup @{binding finish_clausify}
blanchet@35865
   748
    (Scan.succeed (K (SIMPLE_METHOD (Meson_Tactic.expand_defs_tac refl))))
wenzelm@32956
   749
    "cleanup after conversion to clauses";
wenzelm@23442
   750
wenzelm@23442
   751
end;