src/Provers/classical.ML
author wenzelm
Wed Dec 05 03:12:52 2001 +0100 (2001-12-05 ago)
changeset 12376 480303e3fa08
parent 12362 57cd572103c4
child 12401 4363432ef0cd
permissions -rw-r--r--
simplified (and clarified) integration with Pure/ContextRules;
removed "extra" rules as separate slots, only keep xtra_netpair for
single-step view of plain haz/safe rules;
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(*  Title:      Provers/classical.ML
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    ID:         $Id$
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    Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
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    Copyright   1992  University of Cambridge
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Theorem prover for classical reasoning, including predicate calculus, set
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theory, etc.
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Rules must be classified as intro, elim, safe, hazardous (unsafe).
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A rule is unsafe unless it can be applied blindly without harmful results.
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For a rule to be safe, its premises and conclusion should be logically
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equivalent.  There should be no variables in the premises that are not in
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the conclusion.
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*)
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(*higher precedence than := facilitates use of references*)
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infix 4 addSIs addSEs addSDs addIs addEs addDs delrules
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  addSWrapper delSWrapper addWrapper delWrapper
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  addSbefore addSafter addbefore addafter
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  addD2 addE2 addSD2 addSE2;
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(*should be a type abbreviation in signature CLASSICAL*)
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type netpair = (int * (bool * thm)) Net.net * (int * (bool * thm)) Net.net;
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type wrapper = (int -> tactic) -> (int -> tactic);
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signature CLASSICAL_DATA =
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sig
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  val make_elim : thm -> thm    (* Tactic.make_elim or a classical version*)
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  val mp        : thm           (* [| P-->Q;  P |] ==> Q *)
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  val not_elim  : thm           (* [| ~P;  P |] ==> R *)
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  val classical : thm           (* (~P ==> P) ==> P *)
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  val sizef     : thm -> int    (* size function for BEST_FIRST *)
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  val hyp_subst_tacs: (int -> tactic) list
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end;
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signature BASIC_CLASSICAL =
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sig
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  type claset
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  val empty_cs: claset
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  val print_cs: claset -> unit
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  val print_claset: theory -> unit
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  val rep_cs: (* BLAST_DATA in blast.ML dependent on this *)
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    claset -> {safeIs: thm list, safeEs: thm list,
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                 hazIs: thm list, hazEs: thm list,
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                 swrappers: (string * wrapper) list,
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                 uwrappers: (string * wrapper) list,
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                 safe0_netpair: netpair, safep_netpair: netpair,
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                 haz_netpair: netpair, dup_netpair: netpair, xtra_netpair: netpair}
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  val merge_cs          : claset * claset -> claset
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  val addDs             : claset * thm list -> claset
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  val addEs             : claset * thm list -> claset
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  val addIs             : claset * thm list -> claset
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  val addSDs            : claset * thm list -> claset
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  val addSEs            : claset * thm list -> claset
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  val addSIs            : claset * thm list -> claset
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  val delrules          : claset * thm list -> claset
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  val addSWrapper       : claset * (string * wrapper) -> claset
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  val delSWrapper       : claset *  string            -> claset
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  val addWrapper        : claset * (string * wrapper) -> claset
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  val delWrapper        : claset *  string            -> claset
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  val addSbefore        : claset * (string * (int -> tactic)) -> claset
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  val addSafter         : claset * (string * (int -> tactic)) -> claset
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  val addbefore         : claset * (string * (int -> tactic)) -> claset
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  val addafter          : claset * (string * (int -> tactic)) -> claset
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  val addD2             : claset * (string * thm) -> claset
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  val addE2             : claset * (string * thm) -> claset
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  val addSD2            : claset * (string * thm) -> claset
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  val addSE2            : claset * (string * thm) -> claset
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  val appSWrappers      : claset -> wrapper
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  val appWrappers       : claset -> wrapper
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  val claset_ref_of_sg: Sign.sg -> claset ref
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  val claset_ref_of: theory -> claset ref
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  val claset_of_sg: Sign.sg -> claset
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  val claset_of: theory -> claset
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  val CLASET: (claset -> tactic) -> tactic
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  val CLASET': (claset -> 'a -> tactic) -> 'a -> tactic
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  val claset: unit -> claset
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  val claset_ref: unit -> claset ref
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  val fast_tac          : claset -> int -> tactic
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  val slow_tac          : claset -> int -> tactic
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  val weight_ASTAR      : int ref
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  val astar_tac         : claset -> int -> tactic
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  val slow_astar_tac    : claset -> int -> tactic
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  val best_tac          : claset -> int -> tactic
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  val first_best_tac    : claset -> int -> tactic
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  val slow_best_tac     : claset -> int -> tactic
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  val depth_tac         : claset -> int -> int -> tactic
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  val deepen_tac        : claset -> int -> int -> tactic
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  val contr_tac         : int -> tactic
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  val dup_elim          : thm -> thm
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  val dup_intr          : thm -> thm
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  val dup_step_tac      : claset -> int -> tactic
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  val eq_mp_tac         : int -> tactic
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  val haz_step_tac      : claset -> int -> tactic
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  val joinrules         : thm list * thm list -> (bool * thm) list
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  val mp_tac            : int -> tactic
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  val safe_tac          : claset -> tactic
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  val safe_steps_tac    : claset -> int -> tactic
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  val safe_step_tac     : claset -> int -> tactic
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  val clarify_tac       : claset -> int -> tactic
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  val clarify_step_tac  : claset -> int -> tactic
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  val step_tac          : claset -> int -> tactic
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  val slow_step_tac     : claset -> int -> tactic
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  val swap              : thm                 (* ~P ==> (~Q ==> P) ==> Q *)
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  val swapify           : thm list -> thm list
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  val swap_res_tac      : thm list -> int -> tactic
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  val inst_step_tac     : claset -> int -> tactic
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  val inst0_step_tac    : claset -> int -> tactic
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  val instp_step_tac    : claset -> int -> tactic
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  val AddDs             : thm list -> unit
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  val AddEs             : thm list -> unit
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  val AddIs             : thm list -> unit
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  val AddSDs            : thm list -> unit
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  val AddSEs            : thm list -> unit
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  val AddSIs            : thm list -> unit
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  val Delrules          : thm list -> unit
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  val Safe_tac          : tactic
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  val Safe_step_tac     : int -> tactic
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  val Clarify_tac       : int -> tactic
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  val Clarify_step_tac  : int -> tactic
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  val Step_tac          : int -> tactic
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  val Fast_tac          : int -> tactic
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  val Best_tac          : int -> tactic
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  val Slow_tac          : int -> tactic
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  val Slow_best_tac     : int -> tactic
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  val Deepen_tac        : int -> int -> tactic
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end;
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signature CLASSICAL =
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sig
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  include BASIC_CLASSICAL
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  val print_local_claset: Proof.context -> unit
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  val get_local_claset: Proof.context -> claset
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  val put_local_claset: claset -> Proof.context -> Proof.context
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  val safe_dest_global: theory attribute
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  val safe_elim_global: theory attribute
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  val safe_intro_global: theory attribute
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  val haz_dest_global: theory attribute
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  val haz_elim_global: theory attribute
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  val haz_intro_global: theory attribute
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  val rule_del_global: theory attribute
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  val safe_dest_local: Proof.context attribute
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  val safe_elim_local: Proof.context attribute
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  val safe_intro_local: Proof.context attribute
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  val haz_dest_local: Proof.context attribute
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  val haz_elim_local: Proof.context attribute
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  val haz_intro_local: Proof.context attribute
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  val rule_del_local: Proof.context attribute
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  val cla_modifiers: (Args.T list -> (Method.modifier * Args.T list)) list
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  val cla_meth: (claset -> tactic) -> thm list -> Proof.context -> Proof.method
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  val cla_meth': (claset -> int -> tactic) -> thm list -> Proof.context -> Proof.method
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  val cla_method: (claset -> tactic) -> Args.src -> Proof.context -> Proof.method
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  val cla_method': (claset -> int -> tactic) -> Args.src -> Proof.context -> Proof.method
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  val setup: (theory -> theory) list
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end;
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functor ClassicalFun(Data: CLASSICAL_DATA): CLASSICAL =
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struct
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local open Data in
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(*** Useful tactics for classical reasoning ***)
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val imp_elim = (*cannot use bind_thm within a structure!*)
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  store_thm ("imp_elim", Data.make_elim mp);
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(*Prove goal that assumes both P and ~P.
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  No backtracking if it finds an equal assumption.  Perhaps should call
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  ematch_tac instead of eresolve_tac, but then cannot prove ZF/cantor.*)
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val contr_tac = eresolve_tac [not_elim]  THEN'
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                (eq_assume_tac ORELSE' assume_tac);
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(*Finds P-->Q and P in the assumptions, replaces implication by Q.
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  Could do the same thing for P<->Q and P... *)
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fun mp_tac i = eresolve_tac [not_elim, imp_elim] i  THEN  assume_tac i;
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(*Like mp_tac but instantiates no variables*)
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fun eq_mp_tac i = ematch_tac [not_elim, imp_elim] i  THEN  eq_assume_tac i;
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val swap =
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  store_thm ("swap", rule_by_tactic (etac thin_rl 1) (not_elim RS classical));
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(*Creates rules to eliminate ~A, from rules to introduce A*)
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fun swapify intrs = intrs RLN (2, [swap]);
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(*Uses introduction rules in the normal way, or on negated assumptions,
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  trying rules in order. *)
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fun swap_res_tac rls =
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    let fun addrl (rl,brls) = (false, rl) :: (true, rl RSN (2,swap)) :: brls
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    in  assume_tac      ORELSE'
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        contr_tac       ORELSE'
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        biresolve_tac (foldr addrl (rls,[]))
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    end;
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(*Duplication of hazardous rules, for complete provers*)
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fun dup_intr th = zero_var_indexes (th RS classical);
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fun dup_elim th =
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  (case try
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      (rule_by_tactic (TRYALL (etac revcut_rl)))
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      (th RSN (2, revcut_rl) |> assumption 2 |> Seq.hd) of
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    Some th' => th'
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  | _ => error ("Bad format for elimination rule\n" ^ string_of_thm th));
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(**** Classical rule sets ****)
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datatype claset =
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  CS of {safeIs         : thm list,             (*safe introduction rules*)
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         safeEs         : thm list,             (*safe elimination rules*)
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         hazIs          : thm list,             (*unsafe introduction rules*)
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         hazEs          : thm list,             (*unsafe elimination rules*)
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         swrappers      : (string * wrapper) list, (*for transf. safe_step_tac*)
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         uwrappers      : (string * wrapper) list, (*for transforming step_tac*)
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         safe0_netpair  : netpair,              (*nets for trivial cases*)
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         safep_netpair  : netpair,              (*nets for >0 subgoals*)
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         haz_netpair    : netpair,              (*nets for unsafe rules*)
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         dup_netpair    : netpair,              (*nets for duplication*)
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         xtra_netpair   : netpair};             (*nets for extra rules*)
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(*Desired invariants are
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        safe0_netpair = build safe0_brls,
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        safep_netpair = build safep_brls,
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        haz_netpair = build (joinrules(hazIs, hazEs)),
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        dup_netpair = build (joinrules(map dup_intr hazIs,
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                                       map dup_elim hazEs))
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where build = build_netpair(Net.empty,Net.empty),
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      safe0_brls contains all brules that solve the subgoal, and
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      safep_brls contains all brules that generate 1 or more new subgoals.
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The theorem lists are largely comments, though they are used in merge_cs and print_cs.
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Nets must be built incrementally, to save space and time.
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*)
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val empty_netpair = (Net.empty, Net.empty);
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val empty_cs =
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  CS{safeIs     = [],
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     safeEs     = [],
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     hazIs      = [],
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     hazEs      = [],
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     swrappers  = [],
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     uwrappers  = [],
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     safe0_netpair = empty_netpair,
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     safep_netpair = empty_netpair,
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     haz_netpair   = empty_netpair,
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     dup_netpair   = empty_netpair,
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     xtra_netpair  = empty_netpair};
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fun print_cs (CS {safeIs, safeEs, hazIs, hazEs, ...}) =
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  let val pretty_thms = map Display.pretty_thm in
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    [Pretty.big_list "safe introduction rules (intro!):" (pretty_thms safeIs),
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      Pretty.big_list "introduction rules (intro):" (pretty_thms hazIs),
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      Pretty.big_list "safe elimination rules (elim!):" (pretty_thms safeEs),
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      Pretty.big_list "elimination rules (elim):" (pretty_thms hazEs)]
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    |> Pretty.chunks |> Pretty.writeln
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  end;
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fun rep_cs (CS args) = args;
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local
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  fun wrap l tac = foldr (fn ((name,tacf),w) => tacf w) (l, tac);
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in
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  fun appSWrappers (CS{swrappers,...}) = wrap swrappers;
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  fun appWrappers  (CS{uwrappers,...}) = wrap uwrappers;
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end;
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(*** Adding (un)safe introduction or elimination rules.
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    In case of overlap, new rules are tried BEFORE old ones!!
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***)
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(*For use with biresolve_tac.  Combines intro rules with swap to handle negated
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  assumptions.  Pairs elim rules with true. *)
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fun joinrules (intrs, elims) =
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  (map (pair true) (elims @ swapify intrs) @ map (pair false) intrs);
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fun joinrules_simple (intrs, elims) =
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  (map (pair true) elims @ map (pair false) intrs);
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(*Priority: prefer rules with fewest subgoals,
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  then rules added most recently (preferring the head of the list).*)
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fun tag_brls k [] = []
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  | tag_brls k (brl::brls) =
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      (1000000*subgoals_of_brl brl + k, brl) ::
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      tag_brls (k+1) brls;
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fun tag_brls_simple k [] = []
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  | tag_brls_simple k (brl::brls) = (k, brl) :: tag_brls_simple (k+1) brls;
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fun insert_tagged_list kbrls netpr = foldr Tactic.insert_tagged_brl (kbrls, netpr);
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(*Insert into netpair that already has nI intr rules and nE elim rules.
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  Count the intr rules double (to account for swapify).  Negate to give the
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  new insertions the lowest priority.*)
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fun insert (nI, nE) = insert_tagged_list o (tag_brls (~(2*nI+nE))) o joinrules;
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fun insert_simple (nI, nE) = insert_tagged_list o tag_brls_simple (~(nI + nE)) o joinrules_simple;
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fun delete_tagged_list brls netpr = foldr Tactic.delete_tagged_brl (brls, netpr);
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fun delete x = delete_tagged_list (joinrules x);
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fun delete_simple x = delete_tagged_list (joinrules_simple x);
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paulson@2813
   311
val mem_thm = gen_mem eq_thm
paulson@2813
   312
and rem_thm = gen_rem eq_thm;
paulson@2813
   313
paulson@1927
   314
(*Warn if the rule is already present ELSEWHERE in the claset.  The addition
paulson@1927
   315
  is still allowed.*)
wenzelm@12376
   316
fun warn_dup th (CS{safeIs, safeEs, hazIs, hazEs, ...}) =
wenzelm@10736
   317
       if mem_thm (th, safeIs) then
wenzelm@9938
   318
         warning ("Rule already declared as safe introduction (intro!)\n" ^ string_of_thm th)
paulson@2813
   319
  else if mem_thm (th, safeEs) then
wenzelm@9408
   320
         warning ("Rule already declared as safe elimination (elim!)\n" ^ string_of_thm th)
wenzelm@10736
   321
  else if mem_thm (th, hazIs) then
wenzelm@9760
   322
         warning ("Rule already declared as introduction (intro)\n" ^ string_of_thm th)
wenzelm@10736
   323
  else if mem_thm (th, hazEs) then
wenzelm@9760
   324
         warning ("Rule already declared as elimination (elim)\n" ^ string_of_thm th)
paulson@1927
   325
  else ();
paulson@1927
   326
wenzelm@12376
   327
paulson@1800
   328
(*** Safe rules ***)
lcp@982
   329
wenzelm@12376
   330
fun addSI (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   331
              safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair},
wenzelm@9938
   332
           th)  =
wenzelm@10736
   333
  if mem_thm (th, safeIs) then
wenzelm@9938
   334
         (warning ("Ignoring duplicate safe introduction (intro!)\n" ^ string_of_thm th);
wenzelm@9938
   335
          cs)
paulson@1927
   336
  else
lcp@1073
   337
  let val (safe0_rls, safep_rls) = (*0 subgoals vs 1 or more*)
wenzelm@7559
   338
          partition Thm.no_prems [th]
paulson@1927
   339
      val nI = length safeIs + 1
lcp@1073
   340
      and nE = length safeEs
paulson@1927
   341
  in warn_dup th cs;
wenzelm@9938
   342
     CS{safeIs  = th::safeIs,
lcp@1073
   343
        safe0_netpair = insert (nI,nE) (safe0_rls, []) safe0_netpair,
wenzelm@9938
   344
        safep_netpair = insert (nI,nE) (safep_rls, []) safep_netpair,
wenzelm@9938
   345
        safeEs  = safeEs,
wenzelm@9938
   346
        hazIs   = hazIs,
wenzelm@9938
   347
        hazEs   = hazEs,
wenzelm@9938
   348
        swrappers    = swrappers,
wenzelm@9938
   349
        uwrappers    = uwrappers,
wenzelm@9938
   350
        haz_netpair  = haz_netpair,
wenzelm@9938
   351
        dup_netpair  = dup_netpair,
wenzelm@12376
   352
        xtra_netpair = insert_simple (nI,nE) ([th], []) xtra_netpair}
lcp@1073
   353
  end;
lcp@1073
   354
wenzelm@12376
   355
fun addSE (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   356
                    safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair},
wenzelm@9938
   357
           th)  =
wenzelm@10736
   358
  if mem_thm (th, safeEs) then
wenzelm@9938
   359
         (warning ("Ignoring duplicate safe elimination (elim!)\n" ^ string_of_thm th);
wenzelm@9938
   360
          cs)
paulson@1927
   361
  else
lcp@1073
   362
  let val (safe0_rls, safep_rls) = (*0 subgoals vs 1 or more*)
paulson@1927
   363
          partition (fn rl => nprems_of rl=1) [th]
lcp@1073
   364
      val nI = length safeIs
paulson@1927
   365
      and nE = length safeEs + 1
paulson@1927
   366
  in warn_dup th cs;
wenzelm@9938
   367
     CS{safeEs  = th::safeEs,
lcp@1073
   368
        safe0_netpair = insert (nI,nE) ([], safe0_rls) safe0_netpair,
wenzelm@9938
   369
        safep_netpair = insert (nI,nE) ([], safep_rls) safep_netpair,
wenzelm@9938
   370
        safeIs  = safeIs,
wenzelm@9938
   371
        hazIs   = hazIs,
wenzelm@9938
   372
        hazEs   = hazEs,
wenzelm@9938
   373
        swrappers    = swrappers,
wenzelm@9938
   374
        uwrappers    = uwrappers,
wenzelm@9938
   375
        haz_netpair  = haz_netpair,
wenzelm@9938
   376
        dup_netpair  = dup_netpair,
wenzelm@12376
   377
        xtra_netpair = insert_simple (nI,nE) ([], [th]) xtra_netpair}
lcp@1073
   378
  end;
clasohm@0
   379
paulson@1927
   380
fun rev_foldl f (e, l) = foldl f (e, rev l);
paulson@1927
   381
paulson@1927
   382
val op addSIs = rev_foldl addSI;
paulson@1927
   383
val op addSEs = rev_foldl addSE;
paulson@1927
   384
wenzelm@9938
   385
fun cs addSDs ths = cs addSEs (map Data.make_elim ths);
clasohm@0
   386
lcp@1073
   387
paulson@1800
   388
(*** Hazardous (unsafe) rules ***)
clasohm@0
   389
wenzelm@12376
   390
fun addI (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   391
                   safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair},
wenzelm@9938
   392
          th)=
wenzelm@10736
   393
  if mem_thm (th, hazIs) then
wenzelm@9938
   394
         (warning ("Ignoring duplicate introduction (intro)\n" ^ string_of_thm th);
wenzelm@9938
   395
          cs)
paulson@1927
   396
  else
paulson@1927
   397
  let val nI = length hazIs + 1
lcp@1073
   398
      and nE = length hazEs
paulson@1927
   399
  in warn_dup th cs;
wenzelm@9938
   400
     CS{hazIs   = th::hazIs,
wenzelm@9938
   401
        haz_netpair = insert (nI,nE) ([th], []) haz_netpair,
wenzelm@9938
   402
        dup_netpair = insert (nI,nE) (map dup_intr [th], []) dup_netpair,
wenzelm@10736
   403
        safeIs  = safeIs,
wenzelm@9938
   404
        safeEs  = safeEs,
wenzelm@9938
   405
        hazEs   = hazEs,
wenzelm@9938
   406
        swrappers     = swrappers,
wenzelm@9938
   407
        uwrappers     = uwrappers,
wenzelm@9938
   408
        safe0_netpair = safe0_netpair,
wenzelm@9938
   409
        safep_netpair = safep_netpair,
wenzelm@12376
   410
        xtra_netpair = insert_simple (nI,nE) ([th], []) xtra_netpair}
lcp@1073
   411
  end;
lcp@1073
   412
wenzelm@12376
   413
fun addE (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   414
                   safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair},
wenzelm@9938
   415
          th) =
wenzelm@10736
   416
  if mem_thm (th, hazEs) then
wenzelm@9938
   417
         (warning ("Ignoring duplicate elimination (elim)\n" ^ string_of_thm th);
wenzelm@9938
   418
          cs)
paulson@1927
   419
  else
wenzelm@10736
   420
  let val nI = length hazIs
paulson@1927
   421
      and nE = length hazEs + 1
paulson@1927
   422
  in warn_dup th cs;
wenzelm@9938
   423
     CS{hazEs   = th::hazEs,
wenzelm@9938
   424
        haz_netpair = insert (nI,nE) ([], [th]) haz_netpair,
wenzelm@9938
   425
        dup_netpair = insert (nI,nE) ([], map dup_elim [th]) dup_netpair,
wenzelm@10736
   426
        safeIs  = safeIs,
wenzelm@9938
   427
        safeEs  = safeEs,
wenzelm@9938
   428
        hazIs   = hazIs,
wenzelm@9938
   429
        swrappers     = swrappers,
wenzelm@9938
   430
        uwrappers     = uwrappers,
wenzelm@9938
   431
        safe0_netpair = safe0_netpair,
wenzelm@9938
   432
        safep_netpair = safep_netpair,
wenzelm@12376
   433
        xtra_netpair = insert_simple (nI,nE) ([], [th]) xtra_netpair}
lcp@1073
   434
  end;
clasohm@0
   435
paulson@1927
   436
val op addIs = rev_foldl addI;
paulson@1927
   437
val op addEs = rev_foldl addE;
paulson@1927
   438
wenzelm@9938
   439
fun cs addDs ths = cs addEs (map Data.make_elim ths);
clasohm@0
   440
lcp@1073
   441
wenzelm@10736
   442
(*** Deletion of rules
paulson@1800
   443
     Working out what to delete, requires repeating much of the code used
wenzelm@9938
   444
        to insert.
paulson@1927
   445
     Separate functions delSI, etc., are not exported; instead delrules
paulson@2813
   446
        searches in all the lists and chooses the relevant delXX functions.
paulson@1800
   447
***)
paulson@1800
   448
wenzelm@10736
   449
fun delSI th
wenzelm@12376
   450
          (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   451
                    safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair}) =
paulson@2813
   452
 if mem_thm (th, safeIs) then
wenzelm@7559
   453
   let val (safe0_rls, safep_rls) = partition Thm.no_prems [th]
paulson@2813
   454
   in CS{safe0_netpair = delete (safe0_rls, []) safe0_netpair,
wenzelm@9938
   455
         safep_netpair = delete (safep_rls, []) safep_netpair,
wenzelm@9938
   456
         safeIs = rem_thm (safeIs,th),
wenzelm@9938
   457
         safeEs = safeEs,
wenzelm@9938
   458
         hazIs  = hazIs,
wenzelm@9938
   459
         hazEs  = hazEs,
wenzelm@9938
   460
         swrappers    = swrappers,
wenzelm@9938
   461
         uwrappers    = uwrappers,
wenzelm@9938
   462
         haz_netpair  = haz_netpair,
wenzelm@9938
   463
         dup_netpair  = dup_netpair,
wenzelm@12376
   464
         xtra_netpair = delete_simple ([th], []) xtra_netpair}
paulson@2813
   465
   end
paulson@2813
   466
 else cs;
paulson@1800
   467
paulson@2813
   468
fun delSE th
wenzelm@12376
   469
          (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   470
                    safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair}) =
paulson@2813
   471
 if mem_thm (th, safeEs) then
paulson@2813
   472
   let val (safe0_rls, safep_rls) = partition (fn rl => nprems_of rl=1) [th]
paulson@2813
   473
   in CS{safe0_netpair = delete ([], safe0_rls) safe0_netpair,
wenzelm@9938
   474
         safep_netpair = delete ([], safep_rls) safep_netpair,
wenzelm@9938
   475
         safeIs = safeIs,
wenzelm@9938
   476
         safeEs = rem_thm (safeEs,th),
wenzelm@9938
   477
         hazIs  = hazIs,
wenzelm@9938
   478
         hazEs  = hazEs,
wenzelm@9938
   479
         swrappers    = swrappers,
wenzelm@9938
   480
         uwrappers    = uwrappers,
wenzelm@9938
   481
         haz_netpair  = haz_netpair,
wenzelm@9938
   482
         dup_netpair  = dup_netpair,
wenzelm@12376
   483
         xtra_netpair = delete_simple ([], [th]) xtra_netpair}
paulson@2813
   484
   end
paulson@2813
   485
 else cs;
paulson@1800
   486
paulson@1800
   487
paulson@2813
   488
fun delI th
wenzelm@12376
   489
         (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   490
                   safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair}) =
paulson@2813
   491
 if mem_thm (th, hazIs) then
paulson@2813
   492
     CS{haz_netpair = delete ([th], []) haz_netpair,
wenzelm@9938
   493
        dup_netpair = delete ([dup_intr th], []) dup_netpair,
wenzelm@10736
   494
        safeIs  = safeIs,
wenzelm@9938
   495
        safeEs  = safeEs,
wenzelm@9938
   496
        hazIs   = rem_thm (hazIs,th),
wenzelm@9938
   497
        hazEs   = hazEs,
wenzelm@9938
   498
        swrappers     = swrappers,
wenzelm@9938
   499
        uwrappers     = uwrappers,
wenzelm@9938
   500
        safe0_netpair = safe0_netpair,
wenzelm@9938
   501
        safep_netpair = safep_netpair,
wenzelm@12376
   502
        xtra_netpair = delete_simple ([th], []) xtra_netpair}
paulson@2813
   503
 else cs;
paulson@1800
   504
paulson@2813
   505
fun delE th
wenzelm@12376
   506
         (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@9938
   507
                   safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair}) =
paulson@2813
   508
 if mem_thm (th, hazEs) then
paulson@2813
   509
     CS{haz_netpair = delete ([], [th]) haz_netpair,
wenzelm@9938
   510
        dup_netpair = delete ([], [dup_elim th]) dup_netpair,
wenzelm@10736
   511
        safeIs  = safeIs,
wenzelm@9938
   512
        safeEs  = safeEs,
wenzelm@9938
   513
        hazIs   = hazIs,
wenzelm@9938
   514
        hazEs   = rem_thm (hazEs,th),
wenzelm@9938
   515
        swrappers     = swrappers,
wenzelm@9938
   516
        uwrappers     = uwrappers,
wenzelm@9938
   517
        safe0_netpair = safe0_netpair,
wenzelm@9938
   518
        safep_netpair = safep_netpair,
wenzelm@12376
   519
        xtra_netpair = delete_simple ([], [th]) xtra_netpair}
wenzelm@6955
   520
 else cs;
wenzelm@6955
   521
paulson@1800
   522
paulson@2813
   523
(*Delete ALL occurrences of "th" in the claset (perhaps from several lists)*)
wenzelm@12376
   524
fun delrule (cs as CS{safeIs, safeEs, hazIs, hazEs, ...}, th) =
wenzelm@9938
   525
  let val th' = Data.make_elim th in
wenzelm@9938
   526
    if mem_thm (th, safeIs) orelse mem_thm (th, safeEs) orelse
wenzelm@9938
   527
      mem_thm (th, hazIs)  orelse mem_thm (th, hazEs) orelse
wenzelm@12376
   528
      mem_thm (th', safeEs) orelse mem_thm (th', hazEs)
wenzelm@12376
   529
    then delSI th (delSE th (delI th (delE th (delSE th' (delE th' cs)))))
wenzelm@9938
   530
    else (warning ("Undeclared classical rule\n" ^ (string_of_thm th)); cs)
wenzelm@9938
   531
  end;
paulson@1800
   532
paulson@1800
   533
val op delrules = foldl delrule;
paulson@1800
   534
paulson@1800
   535
oheimb@4767
   536
(*** Modifying the wrapper tacticals ***)
wenzelm@10736
   537
fun update_swrappers
wenzelm@12376
   538
(CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@6955
   539
    safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair}) f =
oheimb@4767
   540
 CS{safeIs = safeIs, safeEs = safeEs, hazIs = hazIs, hazEs = hazEs,
oheimb@4767
   541
    swrappers = f swrappers, uwrappers = uwrappers,
oheimb@4767
   542
    safe0_netpair = safe0_netpair, safep_netpair = safep_netpair,
wenzelm@6955
   543
    haz_netpair = haz_netpair, dup_netpair = dup_netpair, xtra_netpair = xtra_netpair};
oheimb@4767
   544
wenzelm@10736
   545
fun update_uwrappers
wenzelm@12376
   546
(CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers,
wenzelm@6955
   547
    safe0_netpair, safep_netpair, haz_netpair, dup_netpair, xtra_netpair}) f =
oheimb@4767
   548
 CS{safeIs = safeIs, safeEs = safeEs, hazIs = hazIs, hazEs = hazEs,
oheimb@4767
   549
    swrappers = swrappers, uwrappers = f uwrappers,
oheimb@4767
   550
    safe0_netpair = safe0_netpair, safep_netpair = safep_netpair,
wenzelm@6955
   551
    haz_netpair = haz_netpair, dup_netpair = dup_netpair, xtra_netpair = xtra_netpair};
oheimb@4767
   552
lcp@982
   553
oheimb@4651
   554
(*Add/replace a safe wrapper*)
oheimb@4767
   555
fun cs addSWrapper new_swrapper = update_swrappers cs (fn swrappers =>
nipkow@9721
   556
    overwrite_warn (swrappers, new_swrapper)
nipkow@9721
   557
       ("Overwriting safe wrapper " ^ fst new_swrapper));
oheimb@4651
   558
oheimb@4651
   559
(*Add/replace an unsafe wrapper*)
oheimb@4767
   560
fun cs addWrapper new_uwrapper = update_uwrappers cs (fn uwrappers =>
nipkow@9721
   561
    overwrite_warn (uwrappers, new_uwrapper)
wenzelm@9938
   562
        ("Overwriting unsafe wrapper "^fst new_uwrapper));
lcp@982
   563
oheimb@4651
   564
(*Remove a safe wrapper*)
oheimb@4767
   565
fun cs delSWrapper name = update_swrappers cs (fn swrappers =>
oheimb@4767
   566
    let val (del,rest) = partition (fn (n,_) => n=name) swrappers
wenzelm@10736
   567
    in if null del then (warning ("No such safe wrapper in claset: "^ name);
wenzelm@9938
   568
                         swrappers) else rest end);
lcp@982
   569
oheimb@4651
   570
(*Remove an unsafe wrapper*)
oheimb@4767
   571
fun cs delWrapper name = update_uwrappers cs (fn uwrappers =>
oheimb@4767
   572
    let val (del,rest) = partition (fn (n,_) => n=name) uwrappers
oheimb@4767
   573
    in if null del then (warning ("No such unsafe wrapper in claset: " ^ name);
oheimb@4767
   574
                         uwrappers) else rest end);
lcp@982
   575
oheimb@11168
   576
(* compose a safe tactic alternatively before/after safe_step_tac *)
wenzelm@10736
   577
fun cs addSbefore  (name,    tac1) =
oheimb@5523
   578
    cs addSWrapper (name, fn tac2 => tac1 ORELSE' tac2);
oheimb@11181
   579
fun cs addSafter   (name,    tac2) =
oheimb@5523
   580
    cs addSWrapper (name, fn tac1 => tac1 ORELSE' tac2);
lcp@982
   581
oheimb@11168
   582
(*compose a tactic alternatively before/after the step tactic *)
wenzelm@10736
   583
fun cs addbefore   (name,    tac1) =
oheimb@5523
   584
    cs addWrapper  (name, fn tac2 => tac1 APPEND' tac2);
oheimb@11181
   585
fun cs addafter    (name,    tac2) =
oheimb@5523
   586
    cs addWrapper  (name, fn tac1 => tac1 APPEND' tac2);
oheimb@4767
   587
wenzelm@10736
   588
fun cs addD2     (name, thm) =
oheimb@11181
   589
    cs addafter  (name, datac thm 1);
wenzelm@10736
   590
fun cs addE2     (name, thm) =
oheimb@11181
   591
    cs addafter  (name, eatac thm 1);
oheimb@11181
   592
fun cs addSD2    (name, thm) =
oheimb@11181
   593
    cs addSafter (name, dmatch_tac [thm] THEN' eq_assume_tac);
oheimb@11181
   594
fun cs addSE2    (name, thm) =
oheimb@11181
   595
    cs addSafter (name, ematch_tac [thm] THEN' eq_assume_tac);
lcp@982
   596
paulson@1711
   597
(*Merge works by adding all new rules of the 2nd claset into the 1st claset.
paulson@1711
   598
  Merging the term nets may look more efficient, but the rather delicate
paulson@1711
   599
  treatment of priority might get muddled up.*)
wenzelm@12376
   600
fun merge_cs (cs as CS{safeIs, safeEs, hazIs, hazEs, ...},
wenzelm@12376
   601
     CS{safeIs=safeIs2, safeEs=safeEs2, hazIs=hazIs2, hazEs=hazEs2, swrappers, uwrappers, ...}) =
paulson@1711
   602
  let val safeIs' = gen_rems eq_thm (safeIs2,safeIs)
paulson@1711
   603
      val safeEs' = gen_rems eq_thm (safeEs2,safeEs)
oheimb@2630
   604
      val  hazIs' = gen_rems eq_thm ( hazIs2, hazIs)
oheimb@2630
   605
      val  hazEs' = gen_rems eq_thm ( hazEs2, hazEs)
oheimb@4767
   606
      val cs1   = cs addSIs safeIs'
wenzelm@9938
   607
                     addSEs safeEs'
wenzelm@9938
   608
                     addIs  hazIs'
wenzelm@9938
   609
                     addEs  hazEs'
oheimb@4767
   610
      val cs2 = update_swrappers cs1 (fn ws => merge_alists ws swrappers);
oheimb@4767
   611
      val cs3 = update_uwrappers cs2 (fn ws => merge_alists ws uwrappers);
wenzelm@10736
   612
  in cs3
paulson@1711
   613
  end;
paulson@1711
   614
lcp@982
   615
paulson@1800
   616
(**** Simple tactics for theorem proving ****)
clasohm@0
   617
clasohm@0
   618
(*Attack subgoals using safe inferences -- matching, not resolution*)
wenzelm@10736
   619
fun safe_step_tac (cs as CS{safe0_netpair,safep_netpair,...}) =
oheimb@4651
   620
  appSWrappers cs (FIRST' [
wenzelm@9938
   621
        eq_assume_tac,
wenzelm@9938
   622
        eq_mp_tac,
wenzelm@9938
   623
        bimatch_from_nets_tac safe0_netpair,
wenzelm@9938
   624
        FIRST' hyp_subst_tacs,
wenzelm@9938
   625
        bimatch_from_nets_tac safep_netpair]);
clasohm@0
   626
oheimb@5757
   627
(*Repeatedly attack a subgoal using safe inferences -- it's deterministic!*)
wenzelm@10736
   628
fun safe_steps_tac cs = REPEAT_DETERM1 o
wenzelm@9938
   629
        (fn i => COND (has_fewer_prems i) no_tac (safe_step_tac cs i));
oheimb@5757
   630
clasohm@0
   631
(*Repeatedly attack subgoals using safe inferences -- it's deterministic!*)
oheimb@5757
   632
fun safe_tac cs = REPEAT_DETERM1 (FIRSTGOAL (safe_steps_tac cs));
lcp@747
   633
paulson@3705
   634
paulson@3705
   635
(*** Clarify_tac: do safe steps without causing branching ***)
paulson@3705
   636
paulson@3705
   637
fun nsubgoalsP n (k,brl) = (subgoals_of_brl brl = n);
paulson@3705
   638
paulson@3705
   639
(*version of bimatch_from_nets_tac that only applies rules that
paulson@3705
   640
  create precisely n subgoals.*)
wenzelm@10736
   641
fun n_bimatch_from_nets_tac n =
wenzelm@11783
   642
    biresolution_from_nets_tac (Tactic.orderlist o filter (nsubgoalsP n)) true;
paulson@3705
   643
paulson@3705
   644
fun eq_contr_tac i = ematch_tac [not_elim] i  THEN  eq_assume_tac i;
paulson@3705
   645
val eq_assume_contr_tac = eq_assume_tac ORELSE' eq_contr_tac;
paulson@3705
   646
paulson@3705
   647
(*Two-way branching is allowed only if one of the branches immediately closes*)
paulson@3705
   648
fun bimatch2_tac netpair i =
paulson@3705
   649
    n_bimatch_from_nets_tac 2 netpair i THEN
paulson@3705
   650
    (eq_assume_contr_tac i ORELSE eq_assume_contr_tac (i+1));
paulson@3705
   651
paulson@3705
   652
(*Attack subgoals using safe inferences -- matching, not resolution*)
wenzelm@10736
   653
fun clarify_step_tac (cs as CS{safe0_netpair,safep_netpair,...}) =
oheimb@4651
   654
  appSWrappers cs (FIRST' [
wenzelm@9938
   655
        eq_assume_contr_tac,
wenzelm@9938
   656
        bimatch_from_nets_tac safe0_netpair,
wenzelm@9938
   657
        FIRST' hyp_subst_tacs,
wenzelm@9938
   658
        n_bimatch_from_nets_tac 1 safep_netpair,
paulson@3705
   659
        bimatch2_tac safep_netpair]);
paulson@3705
   660
paulson@3705
   661
fun clarify_tac cs = SELECT_GOAL (REPEAT_DETERM (clarify_step_tac cs 1));
paulson@3705
   662
paulson@3705
   663
paulson@3705
   664
(*** Unsafe steps instantiate variables or lose information ***)
paulson@3705
   665
paulson@4066
   666
(*Backtracking is allowed among the various these unsafe ways of
paulson@4066
   667
  proving a subgoal.  *)
lcp@747
   668
fun inst0_step_tac (CS{safe0_netpair,safep_netpair,...}) =
wenzelm@10736
   669
  assume_tac                      APPEND'
wenzelm@10736
   670
  contr_tac                       APPEND'
lcp@747
   671
  biresolve_from_nets_tac safe0_netpair;
lcp@747
   672
paulson@4066
   673
(*These unsafe steps could generate more subgoals.*)
lcp@747
   674
fun instp_step_tac (CS{safep_netpair,...}) =
lcp@747
   675
  biresolve_from_nets_tac safep_netpair;
clasohm@0
   676
clasohm@0
   677
(*These steps could instantiate variables and are therefore unsafe.*)
lcp@747
   678
fun inst_step_tac cs = inst0_step_tac cs APPEND' instp_step_tac cs;
clasohm@0
   679
wenzelm@10736
   680
fun haz_step_tac (CS{haz_netpair,...}) =
lcp@681
   681
  biresolve_from_nets_tac haz_netpair;
lcp@681
   682
clasohm@0
   683
(*Single step for the prover.  FAILS unless it makes progress. *)
wenzelm@10736
   684
fun step_tac cs i = safe_tac cs ORELSE appWrappers cs
wenzelm@9938
   685
        (inst_step_tac cs ORELSE' haz_step_tac cs) i;
clasohm@0
   686
clasohm@0
   687
(*Using a "safe" rule to instantiate variables is unsafe.  This tactic
clasohm@0
   688
  allows backtracking from "safe" rules to "unsafe" rules here.*)
wenzelm@10736
   689
fun slow_step_tac cs i = safe_tac cs ORELSE appWrappers cs
wenzelm@9938
   690
        (inst_step_tac cs APPEND' haz_step_tac cs) i;
clasohm@0
   691
paulson@1800
   692
(**** The following tactics all fail unless they solve one goal ****)
clasohm@0
   693
clasohm@0
   694
(*Dumb but fast*)
wenzelm@10382
   695
fun fast_tac cs =
wenzelm@11754
   696
  ObjectLogic.atomize_tac THEN' SELECT_GOAL (DEPTH_SOLVE (step_tac cs 1));
clasohm@0
   697
clasohm@0
   698
(*Slower but smarter than fast_tac*)
wenzelm@10382
   699
fun best_tac cs =
wenzelm@11754
   700
  ObjectLogic.atomize_tac THEN'
clasohm@0
   701
  SELECT_GOAL (BEST_FIRST (has_fewer_prems 1, sizef) (step_tac cs 1));
clasohm@0
   702
oheimb@9402
   703
(*even a bit smarter than best_tac*)
wenzelm@10382
   704
fun first_best_tac cs =
wenzelm@11754
   705
  ObjectLogic.atomize_tac THEN'
oheimb@9402
   706
  SELECT_GOAL (BEST_FIRST (has_fewer_prems 1, sizef) (FIRSTGOAL (step_tac cs)));
oheimb@9402
   707
wenzelm@10382
   708
fun slow_tac cs =
wenzelm@11754
   709
  ObjectLogic.atomize_tac THEN'
wenzelm@10382
   710
  SELECT_GOAL (DEPTH_SOLVE (slow_step_tac cs 1));
clasohm@0
   711
wenzelm@10382
   712
fun slow_best_tac cs =
wenzelm@11754
   713
  ObjectLogic.atomize_tac THEN'
clasohm@0
   714
  SELECT_GOAL (BEST_FIRST (has_fewer_prems 1, sizef) (slow_step_tac cs 1));
clasohm@0
   715
lcp@681
   716
wenzelm@10736
   717
(***ASTAR with weight weight_ASTAR, by Norbert Voelker*)
wenzelm@10736
   718
val weight_ASTAR = ref 5;
paulson@1587
   719
wenzelm@10382
   720
fun astar_tac cs =
wenzelm@11754
   721
  ObjectLogic.atomize_tac THEN'
wenzelm@10382
   722
  SELECT_GOAL
wenzelm@10382
   723
    (ASTAR (has_fewer_prems 1, fn lev => fn thm => size_of_thm thm + !weight_ASTAR * lev)
wenzelm@10382
   724
      (step_tac cs 1));
paulson@1587
   725
wenzelm@10736
   726
fun slow_astar_tac cs =
wenzelm@11754
   727
  ObjectLogic.atomize_tac THEN'
wenzelm@10382
   728
  SELECT_GOAL
wenzelm@10382
   729
    (ASTAR (has_fewer_prems 1, fn lev => fn thm => size_of_thm thm + !weight_ASTAR * lev)
wenzelm@10382
   730
      (slow_step_tac cs 1));
paulson@1587
   731
paulson@1800
   732
(**** Complete tactic, loosely based upon LeanTaP.  This tactic is the outcome
lcp@747
   733
  of much experimentation!  Changing APPEND to ORELSE below would prove
lcp@747
   734
  easy theorems faster, but loses completeness -- and many of the harder
paulson@1800
   735
  theorems such as 43. ****)
lcp@681
   736
lcp@747
   737
(*Non-deterministic!  Could always expand the first unsafe connective.
lcp@747
   738
  That's hard to implement and did not perform better in experiments, due to
lcp@747
   739
  greater search depth required.*)
wenzelm@10736
   740
fun dup_step_tac (cs as (CS{dup_netpair,...})) =
lcp@681
   741
  biresolve_from_nets_tac dup_netpair;
lcp@681
   742
oheimb@5523
   743
(*Searching to depth m. A variant called nodup_depth_tac appears in clasimp.ML*)
oheimb@5757
   744
local
wenzelm@10736
   745
fun slow_step_tac' cs = appWrappers cs
wenzelm@9938
   746
        (instp_step_tac cs APPEND' dup_step_tac cs);
wenzelm@10736
   747
in fun depth_tac cs m i state = SELECT_GOAL
wenzelm@10736
   748
   (safe_steps_tac cs 1 THEN_ELSE
wenzelm@9938
   749
        (DEPTH_SOLVE (depth_tac cs m 1),
wenzelm@9938
   750
         inst0_step_tac cs 1 APPEND COND (K (m=0)) no_tac
wenzelm@9938
   751
                (slow_step_tac' cs 1 THEN DEPTH_SOLVE (depth_tac cs (m-1) 1))
oheimb@5757
   752
        )) i state;
oheimb@5757
   753
end;
lcp@747
   754
wenzelm@10736
   755
(*Search, with depth bound m.
paulson@2173
   756
  This is the "entry point", which does safe inferences first.*)
wenzelm@10736
   757
fun safe_depth_tac cs m =
wenzelm@10736
   758
  SUBGOAL
lcp@681
   759
    (fn (prem,i) =>
lcp@681
   760
      let val deti =
wenzelm@9938
   761
          (*No Vars in the goal?  No need to backtrack between goals.*)
wenzelm@9938
   762
          case term_vars prem of
wenzelm@10736
   763
              []        => DETERM
wenzelm@9938
   764
            | _::_      => I
wenzelm@10736
   765
      in  SELECT_GOAL (TRY (safe_tac cs) THEN
wenzelm@9938
   766
                       DEPTH_SOLVE (deti (depth_tac cs m 1))) i
lcp@747
   767
      end);
lcp@681
   768
paulson@2868
   769
fun deepen_tac cs = DEEPEN (2,10) (safe_depth_tac cs);
lcp@681
   770
wenzelm@4079
   771
berghofe@1724
   772
wenzelm@4079
   773
(** claset theory data **)
wenzelm@4079
   774
wenzelm@7354
   775
(* theory data kind 'Provers/claset' *)
berghofe@1724
   776
wenzelm@7354
   777
structure GlobalClasetArgs =
wenzelm@7354
   778
struct
wenzelm@7354
   779
  val name = "Provers/claset";
wenzelm@7354
   780
  type T = claset ref;
wenzelm@4079
   781
wenzelm@7354
   782
  val empty = ref empty_cs;
wenzelm@7354
   783
  fun copy (ref cs) = (ref cs): T;            (*create new reference!*)
wenzelm@6556
   784
  val prep_ext = copy;
wenzelm@7354
   785
  fun merge (ref cs1, ref cs2) = ref (merge_cs (cs1, cs2));
wenzelm@7354
   786
  fun print _ (ref cs) = print_cs cs;
wenzelm@7354
   787
end;
berghofe@1724
   788
wenzelm@7354
   789
structure GlobalClaset = TheoryDataFun(GlobalClasetArgs);
wenzelm@7354
   790
val print_claset = GlobalClaset.print;
wenzelm@7354
   791
val claset_ref_of_sg = GlobalClaset.get_sg;
wenzelm@7354
   792
val claset_ref_of = GlobalClaset.get;
wenzelm@4079
   793
berghofe@1724
   794
wenzelm@4079
   795
(* access claset *)
berghofe@1724
   796
wenzelm@4079
   797
val claset_of_sg = ! o claset_ref_of_sg;
wenzelm@6391
   798
val claset_of = claset_of_sg o Theory.sign_of;
paulson@1800
   799
wenzelm@6391
   800
fun CLASET tacf state = tacf (claset_of_sg (Thm.sign_of_thm state)) state;
wenzelm@6391
   801
fun CLASET' tacf i state = tacf (claset_of_sg (Thm.sign_of_thm state)) i state;
paulson@3705
   802
wenzelm@5028
   803
val claset = claset_of o Context.the_context;
wenzelm@6391
   804
val claset_ref = claset_ref_of_sg o Theory.sign_of o Context.the_context;
wenzelm@4079
   805
paulson@3705
   806
wenzelm@4079
   807
(* change claset *)
paulson@1800
   808
wenzelm@4079
   809
fun change_claset f x = claset_ref () := (f (claset (), x));
berghofe@1724
   810
wenzelm@4079
   811
val AddDs = change_claset (op addDs);
wenzelm@4079
   812
val AddEs = change_claset (op addEs);
wenzelm@4079
   813
val AddIs = change_claset (op addIs);
wenzelm@4079
   814
val AddSDs = change_claset (op addSDs);
wenzelm@4079
   815
val AddSEs = change_claset (op addSEs);
wenzelm@4079
   816
val AddSIs = change_claset (op addSIs);
wenzelm@4079
   817
val Delrules = change_claset (op delrules);
paulson@3727
   818
wenzelm@4079
   819
wenzelm@5841
   820
(* proof data kind 'Provers/claset' *)
wenzelm@5841
   821
wenzelm@5841
   822
structure LocalClasetArgs =
wenzelm@5841
   823
struct
wenzelm@5841
   824
  val name = "Provers/claset";
wenzelm@5841
   825
  type T = claset;
wenzelm@5841
   826
  val init = claset_of;
wenzelm@5841
   827
  fun print _ cs = print_cs cs;
wenzelm@5841
   828
end;
wenzelm@5841
   829
wenzelm@5841
   830
structure LocalClaset = ProofDataFun(LocalClasetArgs);
wenzelm@5841
   831
val print_local_claset = LocalClaset.print;
wenzelm@5841
   832
val get_local_claset = LocalClaset.get;
wenzelm@5841
   833
val put_local_claset = LocalClaset.put;
wenzelm@5841
   834
wenzelm@5841
   835
wenzelm@5885
   836
(* attributes *)
wenzelm@5885
   837
wenzelm@5885
   838
fun change_global_cs f (thy, th) =
wenzelm@5885
   839
  let val r = claset_ref_of thy
wenzelm@6096
   840
  in r := f (! r, [th]); (thy, th) end;
wenzelm@5885
   841
wenzelm@5885
   842
fun change_local_cs f (ctxt, th) =
wenzelm@6096
   843
  let val cs = f (get_local_claset ctxt, [th])
wenzelm@5885
   844
  in (put_local_claset cs ctxt, th) end;
wenzelm@5885
   845
wenzelm@5885
   846
val safe_dest_global = change_global_cs (op addSDs);
wenzelm@5885
   847
val safe_elim_global = change_global_cs (op addSEs);
wenzelm@5885
   848
val safe_intro_global = change_global_cs (op addSIs);
wenzelm@6955
   849
val haz_dest_global = change_global_cs (op addDs);
wenzelm@6955
   850
val haz_elim_global = change_global_cs (op addEs);
wenzelm@6955
   851
val haz_intro_global = change_global_cs (op addIs);
wenzelm@12376
   852
val rule_del_global = change_global_cs (op delrules) o ContextRules.rule_del_global;
wenzelm@5885
   853
wenzelm@6955
   854
val safe_dest_local = change_local_cs (op addSDs);
wenzelm@6955
   855
val safe_elim_local = change_local_cs (op addSEs);
wenzelm@6955
   856
val safe_intro_local = change_local_cs (op addSIs);
wenzelm@5885
   857
val haz_dest_local = change_local_cs (op addDs);
wenzelm@5885
   858
val haz_elim_local = change_local_cs (op addEs);
wenzelm@5885
   859
val haz_intro_local = change_local_cs (op addIs);
wenzelm@12376
   860
val rule_del_local = change_local_cs (op delrules) o ContextRules.rule_del_local;
wenzelm@5885
   861
wenzelm@5885
   862
wenzelm@4079
   863
(* tactics referring to the implicit claset *)
paulson@1800
   864
wenzelm@4079
   865
(*the abstraction over the proof state delays the dereferencing*)
wenzelm@9938
   866
fun Safe_tac st           = safe_tac (claset()) st;
wenzelm@9938
   867
fun Safe_step_tac i st    = safe_step_tac (claset()) i st;
wenzelm@4079
   868
fun Clarify_step_tac i st = clarify_step_tac (claset()) i st;
wenzelm@9938
   869
fun Clarify_tac i st      = clarify_tac (claset()) i st;
wenzelm@9938
   870
fun Step_tac i st         = step_tac (claset()) i st;
wenzelm@9938
   871
fun Fast_tac i st         = fast_tac (claset()) i st;
wenzelm@9938
   872
fun Best_tac i st         = best_tac (claset()) i st;
wenzelm@9938
   873
fun Slow_tac i st         = slow_tac (claset()) i st;
wenzelm@9938
   874
fun Slow_best_tac i st    = slow_best_tac (claset()) i st;
wenzelm@9938
   875
fun Deepen_tac m          = deepen_tac (claset()) m;
paulson@2066
   876
paulson@1800
   877
wenzelm@10736
   878
end;
wenzelm@5841
   879
wenzelm@5841
   880
wenzelm@5841
   881
wenzelm@5885
   882
(** concrete syntax of attributes **)
wenzelm@5841
   883
wenzelm@5841
   884
(* add / del rules *)
wenzelm@5841
   885
wenzelm@5841
   886
val introN = "intro";
wenzelm@5841
   887
val elimN = "elim";
wenzelm@5841
   888
val destN = "dest";
wenzelm@9938
   889
val ruleN = "rule";
wenzelm@5841
   890
wenzelm@12376
   891
fun add_rule xtra haz safe = Attrib.syntax
wenzelm@12376
   892
 (Scan.lift (Args.query |-- Scan.option Args.nat >> xtra || Args.bang >> K safe ||
wenzelm@12376
   893
  Scan.succeed haz));
wenzelm@5841
   894
wenzelm@12376
   895
fun del_rule att = Attrib.syntax (Scan.lift Args.del >> K att);
wenzelm@5841
   896
wenzelm@5841
   897
wenzelm@5841
   898
(* setup_attrs *)
wenzelm@5841
   899
wenzelm@9941
   900
fun elim_format x = Attrib.no_args (Drule.rule_attribute (K Data.make_elim)) x;
wenzelm@9184
   901
wenzelm@5841
   902
val setup_attrs = Attrib.add_attributes
wenzelm@9941
   903
 [("elim_format", (elim_format, elim_format),
wenzelm@9941
   904
    "destruct rule turned into elimination rule format (classical)"),
wenzelm@12376
   905
  (destN,
wenzelm@12376
   906
   (add_rule ContextRules.dest_query_global haz_dest_global safe_dest_global,
wenzelm@12376
   907
    add_rule ContextRules.dest_query_local haz_dest_local safe_dest_local),
wenzelm@12376
   908
    "declaration of destruction rule"),
wenzelm@12376
   909
  (elimN,
wenzelm@12376
   910
   (add_rule ContextRules.elim_query_global haz_elim_global safe_elim_global,
wenzelm@12376
   911
    add_rule ContextRules.elim_query_local haz_elim_local safe_elim_local),
wenzelm@12376
   912
    "declaration of elimination rule"),
wenzelm@12376
   913
  (introN,
wenzelm@12376
   914
   (add_rule ContextRules.intro_query_global haz_intro_global safe_intro_global,
wenzelm@12376
   915
    add_rule ContextRules.intro_query_local haz_intro_local safe_intro_local),
wenzelm@12376
   916
    "declaration of introduction rule"),
wenzelm@12376
   917
  (ruleN, (del_rule rule_del_global, del_rule rule_del_local),
wenzelm@12376
   918
    "remove declaration of intro/elim/dest rule")];
wenzelm@5841
   919
wenzelm@5841
   920
wenzelm@5841
   921
wenzelm@7230
   922
(** proof methods **)
wenzelm@7230
   923
wenzelm@7230
   924
(* METHOD_CLASET' *)
wenzelm@5841
   925
wenzelm@8098
   926
fun METHOD_CLASET' tac ctxt =
wenzelm@10394
   927
  Method.METHOD (HEADGOAL o tac ctxt (get_local_claset ctxt));
wenzelm@7230
   928
wenzelm@7230
   929
wenzelm@7230
   930
local
wenzelm@7230
   931
wenzelm@12376
   932
fun may_unify t net = map snd (Tactic.orderlist (Net.unify_term net t));
wenzelm@5841
   933
wenzelm@12376
   934
fun find_erules [] = K []
wenzelm@12376
   935
  | find_erules (fact :: _) = may_unify (Logic.strip_assums_concl (#prop (Thm.rep_thm fact)));
wenzelm@12376
   936
fun find_irules goal = may_unify (Logic.strip_assums_concl goal);
wenzelm@12376
   937
fun find_rules (inet, enet) facts goal = find_erules facts enet @ find_irules goal inet;
wenzelm@5841
   938
wenzelm@12376
   939
fun some_rule_tac ctxt (CS {xtra_netpair, ...}) facts = SUBGOAL (fn (goal, i) =>
wenzelm@5841
   940
  let
wenzelm@12376
   941
    val [rules1, rules2, rules4] = ContextRules.find_rules ctxt facts goal;
wenzelm@12376
   942
    val rules3 = find_rules xtra_netpair facts goal;
wenzelm@12376
   943
    val rules = rules1 @ rules2 @ rules3 @ rules4;
wenzelm@12376
   944
    val ruleq = Method.multi_resolves facts rules;
wenzelm@12376
   945
  in
wenzelm@12376
   946
    Method.trace ctxt rules;
wenzelm@12376
   947
    fn st => Seq.flat (Seq.map (fn rule => Tactic.rtac rule i st) ruleq)
wenzelm@12376
   948
  end);
wenzelm@5841
   949
wenzelm@12376
   950
fun rule_tac [] ctxt cs facts = some_rule_tac ctxt cs facts
wenzelm@10394
   951
  | rule_tac rules _ _ facts = Method.rule_tac rules facts;
wenzelm@7281
   952
wenzelm@10382
   953
fun default_tac rules ctxt cs facts =
wenzelm@10394
   954
  rule_tac rules ctxt cs facts ORELSE'
wenzelm@10382
   955
  AxClass.default_intro_classes_tac facts;
wenzelm@10309
   956
wenzelm@7230
   957
in
wenzelm@7281
   958
  val rule = METHOD_CLASET' o rule_tac;
wenzelm@10394
   959
  val default = METHOD_CLASET' o default_tac;
wenzelm@7230
   960
end;
wenzelm@5841
   961
wenzelm@5841
   962
wenzelm@7230
   963
(* contradiction method *)
wenzelm@6502
   964
wenzelm@7425
   965
val contradiction = Method.rule [Data.not_elim, Data.not_elim COMP Drule.swap_prems_rl];
wenzelm@6502
   966
wenzelm@6502
   967
wenzelm@6502
   968
(* automatic methods *)
wenzelm@5841
   969
wenzelm@5927
   970
val cla_modifiers =
wenzelm@12376
   971
 [Args.$$$ destN -- Args.bang_colon >> K ((I, safe_dest_local): Method.modifier),
wenzelm@10034
   972
  Args.$$$ destN -- Args.colon >> K (I, haz_dest_local),
wenzelm@10034
   973
  Args.$$$ elimN -- Args.bang_colon >> K (I, safe_elim_local),
wenzelm@10034
   974
  Args.$$$ elimN -- Args.colon >> K (I, haz_elim_local),
wenzelm@10034
   975
  Args.$$$ introN -- Args.bang_colon >> K (I, safe_intro_local),
wenzelm@10034
   976
  Args.$$$ introN -- Args.colon >> K (I, haz_intro_local),
wenzelm@10034
   977
  Args.del -- Args.colon >> K (I, rule_del_local)];
wenzelm@5927
   978
wenzelm@7559
   979
fun cla_meth tac prems ctxt = Method.METHOD (fn facts =>
wenzelm@7559
   980
  ALLGOALS (Method.insert_tac (prems @ facts)) THEN tac (get_local_claset ctxt));
wenzelm@7132
   981
wenzelm@7559
   982
fun cla_meth' tac prems ctxt = Method.METHOD (fn facts =>
wenzelm@8168
   983
  HEADGOAL (Method.insert_tac (prems @ facts) THEN' tac (get_local_claset ctxt)));
wenzelm@5841
   984
wenzelm@7559
   985
val cla_method = Method.bang_sectioned_args cla_modifiers o cla_meth;
wenzelm@7559
   986
val cla_method' = Method.bang_sectioned_args cla_modifiers o cla_meth';
wenzelm@5841
   987
wenzelm@5841
   988
wenzelm@5841
   989
wenzelm@5841
   990
(** setup_methods **)
wenzelm@5841
   991
wenzelm@5841
   992
val setup_methods = Method.add_methods
wenzelm@12376
   993
 [("default", Method.thms_ctxt_args default, "apply some intro/elim rule (potentially classical)"),
wenzelm@12376
   994
  ("rule", Method.thms_ctxt_args rule, "apply some intro/elim rule (potentially classical)"),
wenzelm@6502
   995
  ("contradiction", Method.no_args contradiction, "proof by contradiction"),
wenzelm@10821
   996
  ("clarify", cla_method' (CHANGED_PROP oo clarify_tac), "repeatedly apply safe steps"),
wenzelm@7004
   997
  ("fast", cla_method' fast_tac, "classical prover (depth-first)"),
wenzelm@9806
   998
  ("slow", cla_method' slow_tac, "classical prover (slow depth-first)"),
wenzelm@9773
   999
  ("best", cla_method' best_tac, "classical prover (best-first)"),
wenzelm@10821
  1000
  ("safe", cla_method (CHANGED_PROP o safe_tac), "classical prover (apply safe rules)")];
wenzelm@5841
  1001
wenzelm@5841
  1002
wenzelm@5841
  1003
wenzelm@5841
  1004
(** theory setup **)
wenzelm@5841
  1005
wenzelm@7354
  1006
val setup = [GlobalClaset.init, LocalClaset.init, setup_attrs, setup_methods];
wenzelm@5841
  1007
wenzelm@5841
  1008
wenzelm@8667
  1009
wenzelm@8667
  1010
(** outer syntax **)
wenzelm@8667
  1011
wenzelm@8667
  1012
val print_clasetP =
wenzelm@8667
  1013
  OuterSyntax.improper_command "print_claset" "print context of Classical Reasoner"
wenzelm@8667
  1014
    OuterSyntax.Keyword.diag
wenzelm@9513
  1015
    (Scan.succeed (Toplevel.no_timing o Toplevel.unknown_context o (Toplevel.keep
wenzelm@9010
  1016
      (Toplevel.node_case print_claset (print_local_claset o Proof.context_of)))));
wenzelm@8667
  1017
wenzelm@8667
  1018
val _ = OuterSyntax.add_parsers [print_clasetP];
wenzelm@8667
  1019
wenzelm@8667
  1020
wenzelm@5841
  1021
end;