src/Provers/classical.ML
author wenzelm
Fri Apr 30 18:10:03 1999 +0200 (1999-04-30)
changeset 6556 daa00919502b
parent 6502 bc30e13b36a8
child 6955 9e2d97ef55d2
permissions -rw-r--r--
theory data: copy;
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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 intr, 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 addSaltern addbefore addaltern
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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 CLASET_THY_DATA =
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sig
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  val clasetN: string
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  val clasetK: Object.kind
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  exception ClasetData of Object.T ref
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  val setup: (theory -> theory) list
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  val fix_methods: Object.T * (Object.T -> Object.T) * (Object.T -> Object.T) *
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    (Object.T * Object.T -> Object.T) * (Sign.sg -> Object.T -> unit) -> unit
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end;
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signature CLASSICAL_DATA =
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sig
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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}
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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 addSaltern 	: claset * (string * (int -> tactic)) -> claset
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  val addbefore 	: claset * (string * (int -> tactic)) -> claset
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  val addaltern	 	: 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 trace_rules	: bool ref
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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 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 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 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 delrule_global: theory 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 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 delrule_local: Proof.context attribute
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  val cla_modifiers: (Args.T list -> (Proof.context attribute * Args.T list)) list
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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 single_tac: claset -> thm list -> int -> tactic
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  val setup: (theory -> theory) list
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end;
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structure ClasetThyData: CLASET_THY_DATA =
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struct
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(* data kind claset -- forward declaration *)
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val clasetN = "Provers/claset";
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val clasetK = Object.kind clasetN;
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exception ClasetData of Object.T ref;
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local
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  fun undef _ = raise Match;
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  val empty_ref = ref ERROR;
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  val copy_fn = ref (undef: Object.T -> Object.T);
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  val prep_ext_fn = ref (undef: Object.T -> Object.T);
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  val merge_fn = ref (undef: Object.T * Object.T -> Object.T);
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  val print_fn = ref (undef: Sign.sg -> Object.T -> unit);
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  val empty = ClasetData empty_ref;
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  fun copy exn = ! copy_fn exn;
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  fun prep_ext exn = ! prep_ext_fn exn;
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  fun merge exn = ! merge_fn exn;
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  fun print sg exn = ! print_fn sg exn;
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in
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  val setup = [Theory.init_data clasetK (empty, copy, prep_ext, merge, print)];
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  fun fix_methods (e, cp, ext, mrg, prt) =
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    (empty_ref := e; copy_fn := cp; prep_ext_fn := ext; merge_fn := mrg; print_fn := prt);
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end;
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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 ClasetThyData 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", 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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    th RSN (2, revcut_rl) |> assumption 2 |> Seq.hd |> 
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    rule_by_tactic (TRYALL (etac revcut_rl))
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    handle _ => 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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(*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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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.writeln (Pretty.big_list "safe introduction rules:" (pretty_thms safeIs));
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    Pretty.writeln (Pretty.big_list "unsafe introduction rules:" (pretty_thms hazIs));
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    Pretty.writeln (Pretty.big_list "safe elimination rules:" (pretty_thms safeEs));
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    Pretty.writeln (Pretty.big_list "unsafe elimination rules:" (pretty_thms hazEs))
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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 calc_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,...}) = calc_wrap swrappers;
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  fun appWrappers  (CS{uwrappers,...}) = calc_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 intr 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)  @
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   320
     map (pair false) intrs);
lcp@1073
   321
lcp@1073
   322
(*Priority: prefer rules with fewest subgoals, 
paulson@1231
   323
  then rules added most recently (preferring the head of the list).*)
lcp@1073
   324
fun tag_brls k [] = []
lcp@1073
   325
  | tag_brls k (brl::brls) =
lcp@1073
   326
      (1000000*subgoals_of_brl brl + k, brl) :: 
lcp@1073
   327
      tag_brls (k+1) brls;
lcp@1073
   328
paulson@1800
   329
fun insert_tagged_list kbrls netpr = foldr insert_tagged_brl (kbrls, netpr);
lcp@1073
   330
lcp@1073
   331
(*Insert into netpair that already has nI intr rules and nE elim rules.
lcp@1073
   332
  Count the intr rules double (to account for swapify).  Negate to give the
lcp@1073
   333
  new insertions the lowest priority.*)
lcp@1073
   334
fun insert (nI,nE) = insert_tagged_list o (tag_brls (~(2*nI+nE))) o joinrules;
lcp@1073
   335
paulson@1800
   336
fun delete_tagged_list brls netpr = foldr delete_tagged_brl (brls, netpr);
lcp@1073
   337
paulson@1800
   338
val delete = delete_tagged_list o joinrules;
paulson@1800
   339
paulson@2813
   340
val mem_thm = gen_mem eq_thm
paulson@2813
   341
and rem_thm = gen_rem eq_thm;
paulson@2813
   342
paulson@1927
   343
(*Warn if the rule is already present ELSEWHERE in the claset.  The addition
paulson@1927
   344
  is still allowed.*)
paulson@1927
   345
fun warn_dup th (CS{safeIs, safeEs, hazIs, hazEs, ...}) = 
paulson@2813
   346
       if mem_thm (th, safeIs) then 
wenzelm@4079
   347
	 warning ("Rule already in claset as Safe Intr\n" ^ string_of_thm th)
paulson@2813
   348
  else if mem_thm (th, safeEs) then
wenzelm@4079
   349
         warning ("Rule already in claset as Safe Elim\n" ^ string_of_thm th)
paulson@2813
   350
  else if mem_thm (th, hazIs) then 
wenzelm@4079
   351
         warning ("Rule already in claset as unsafe Intr\n" ^ string_of_thm th)
paulson@2813
   352
  else if mem_thm (th, hazEs) then 
wenzelm@4079
   353
         warning ("Rule already in claset as unsafe Elim\n" ^ string_of_thm th)
paulson@1927
   354
  else ();
paulson@1927
   355
paulson@1800
   356
(*** Safe rules ***)
lcp@982
   357
oheimb@4651
   358
fun addSI (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   359
	      safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   360
	   th)  =
paulson@2813
   361
  if mem_thm (th, safeIs) then 
wenzelm@4079
   362
	 (warning ("Ignoring duplicate Safe Intr\n" ^ string_of_thm th);
paulson@1927
   363
	  cs)
paulson@1927
   364
  else
lcp@1073
   365
  let val (safe0_rls, safep_rls) = (*0 subgoals vs 1 or more*)
paulson@1927
   366
          partition (fn rl => nprems_of rl=0) [th]
paulson@1927
   367
      val nI = length safeIs + 1
lcp@1073
   368
      and nE = length safeEs
paulson@1927
   369
  in warn_dup th cs;
paulson@1927
   370
     CS{safeIs	= th::safeIs,
lcp@1073
   371
        safe0_netpair = insert (nI,nE) (safe0_rls, []) safe0_netpair,
lcp@1073
   372
	safep_netpair = insert (nI,nE) (safep_rls, []) safep_netpair,
lcp@1073
   373
	safeEs	= safeEs,
lcp@1073
   374
	hazIs	= hazIs,
lcp@1073
   375
	hazEs	= hazEs,
oheimb@4651
   376
	swrappers    = swrappers,
oheimb@4651
   377
	uwrappers    = uwrappers,
oheimb@2630
   378
	haz_netpair  = haz_netpair,
oheimb@2630
   379
	dup_netpair  = dup_netpair}
lcp@1073
   380
  end;
lcp@1073
   381
oheimb@4651
   382
fun addSE (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   383
		    safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   384
	   th)  =
paulson@2813
   385
  if mem_thm (th, safeEs) then 
wenzelm@4079
   386
	 (warning ("Ignoring duplicate Safe Elim\n" ^ string_of_thm th);
paulson@1927
   387
	  cs)
paulson@1927
   388
  else
lcp@1073
   389
  let val (safe0_rls, safep_rls) = (*0 subgoals vs 1 or more*)
paulson@1927
   390
          partition (fn rl => nprems_of rl=1) [th]
lcp@1073
   391
      val nI = length safeIs
paulson@1927
   392
      and nE = length safeEs + 1
paulson@1927
   393
  in warn_dup th cs;
paulson@1927
   394
     CS{safeEs	= th::safeEs,
lcp@1073
   395
        safe0_netpair = insert (nI,nE) ([], safe0_rls) safe0_netpair,
lcp@1073
   396
	safep_netpair = insert (nI,nE) ([], safep_rls) safep_netpair,
lcp@1073
   397
	safeIs	= safeIs,
lcp@1073
   398
	hazIs	= hazIs,
lcp@1073
   399
	hazEs	= hazEs,
oheimb@4651
   400
	swrappers    = swrappers,
oheimb@4651
   401
	uwrappers    = uwrappers,
oheimb@2630
   402
	haz_netpair  = haz_netpair,
oheimb@2630
   403
	dup_netpair  = dup_netpair}
lcp@1073
   404
  end;
clasohm@0
   405
paulson@1927
   406
fun rev_foldl f (e, l) = foldl f (e, rev l);
paulson@1927
   407
paulson@1927
   408
val op addSIs = rev_foldl addSI;
paulson@1927
   409
val op addSEs = rev_foldl addSE;
paulson@1927
   410
clasohm@0
   411
fun cs addSDs ths = cs addSEs (map make_elim ths);
clasohm@0
   412
lcp@1073
   413
paulson@1800
   414
(*** Hazardous (unsafe) rules ***)
clasohm@0
   415
oheimb@4651
   416
fun addI (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   417
		   safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   418
	  th)=
paulson@2813
   419
  if mem_thm (th, hazIs) then 
wenzelm@4079
   420
	 (warning ("Ignoring duplicate unsafe Intr\n" ^ string_of_thm th);
paulson@1927
   421
	  cs)
paulson@1927
   422
  else
paulson@1927
   423
  let val nI = length hazIs + 1
lcp@1073
   424
      and nE = length hazEs
paulson@1927
   425
  in warn_dup th cs;
paulson@1927
   426
     CS{hazIs	= th::hazIs,
paulson@1927
   427
	haz_netpair = insert (nI,nE) ([th], []) haz_netpair,
paulson@1927
   428
	dup_netpair = insert (nI,nE) (map dup_intr [th], []) dup_netpair,
lcp@1073
   429
	safeIs 	= safeIs, 
lcp@1073
   430
	safeEs	= safeEs,
lcp@1073
   431
	hazEs	= hazEs,
oheimb@4651
   432
	swrappers     = swrappers,
oheimb@4651
   433
	uwrappers     = uwrappers,
lcp@1073
   434
	safe0_netpair = safe0_netpair,
lcp@1073
   435
	safep_netpair = safep_netpair}
lcp@1073
   436
  end;
lcp@1073
   437
oheimb@4651
   438
fun addE (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   439
		   safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   440
	  th) =
paulson@2813
   441
  if mem_thm (th, hazEs) then 
wenzelm@4079
   442
	 (warning ("Ignoring duplicate unsafe Elim\n" ^ string_of_thm th);
paulson@1927
   443
	  cs)
paulson@1927
   444
  else
lcp@1073
   445
  let val nI = length hazIs 
paulson@1927
   446
      and nE = length hazEs + 1
paulson@1927
   447
  in warn_dup th cs;
paulson@1927
   448
     CS{hazEs	= th::hazEs,
paulson@1927
   449
	haz_netpair = insert (nI,nE) ([], [th]) haz_netpair,
paulson@1927
   450
	dup_netpair = insert (nI,nE) ([], map dup_elim [th]) dup_netpair,
lcp@1073
   451
	safeIs	= safeIs, 
lcp@1073
   452
	safeEs	= safeEs,
lcp@1073
   453
	hazIs	= hazIs,
oheimb@4651
   454
	swrappers     = swrappers,
oheimb@4651
   455
	uwrappers     = uwrappers,
lcp@1073
   456
	safe0_netpair = safe0_netpair,
lcp@1073
   457
	safep_netpair = safep_netpair}
lcp@1073
   458
  end;
clasohm@0
   459
paulson@1927
   460
val op addIs = rev_foldl addI;
paulson@1927
   461
val op addEs = rev_foldl addE;
paulson@1927
   462
clasohm@0
   463
fun cs addDs ths = cs addEs (map make_elim ths);
clasohm@0
   464
lcp@1073
   465
paulson@1800
   466
(*** Deletion of rules 
paulson@1800
   467
     Working out what to delete, requires repeating much of the code used
paulson@1800
   468
	to insert.
paulson@1927
   469
     Separate functions delSI, etc., are not exported; instead delrules
paulson@2813
   470
        searches in all the lists and chooses the relevant delXX functions.
paulson@1800
   471
***)
paulson@1800
   472
paulson@2813
   473
fun delSI th 
oheimb@4651
   474
          (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   475
		    safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   476
 if mem_thm (th, safeIs) then
paulson@2813
   477
   let val (safe0_rls, safep_rls) = partition (fn rl => nprems_of rl=0) [th]
paulson@2813
   478
   in CS{safe0_netpair = delete (safe0_rls, []) safe0_netpair,
paulson@2813
   479
	 safep_netpair = delete (safep_rls, []) safep_netpair,
paulson@2813
   480
	 safeIs	= rem_thm (safeIs,th),
paulson@2813
   481
	 safeEs	= safeEs,
paulson@2813
   482
	 hazIs	= hazIs,
paulson@2813
   483
	 hazEs	= hazEs,
oheimb@4651
   484
	 swrappers    = swrappers,
oheimb@4651
   485
	 uwrappers    = uwrappers,
paulson@2813
   486
	 haz_netpair  = haz_netpair,
paulson@2813
   487
	 dup_netpair  = dup_netpair}
paulson@2813
   488
   end
paulson@2813
   489
 else cs;
paulson@1800
   490
paulson@2813
   491
fun delSE th
oheimb@4651
   492
          (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   493
	            safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   494
 if mem_thm (th, safeEs) then
paulson@2813
   495
   let val (safe0_rls, safep_rls) = partition (fn rl => nprems_of rl=1) [th]
paulson@2813
   496
   in CS{safe0_netpair = delete ([], safe0_rls) safe0_netpair,
paulson@2813
   497
	 safep_netpair = delete ([], safep_rls) safep_netpair,
paulson@2813
   498
	 safeIs	= safeIs,
paulson@2813
   499
	 safeEs	= rem_thm (safeEs,th),
paulson@2813
   500
	 hazIs	= hazIs,
paulson@2813
   501
	 hazEs	= hazEs,
oheimb@4651
   502
	 swrappers    = swrappers,
oheimb@4651
   503
	 uwrappers    = uwrappers,
paulson@2813
   504
	 haz_netpair  = haz_netpair,
paulson@2813
   505
	 dup_netpair  = dup_netpair}
paulson@2813
   506
   end
paulson@2813
   507
 else cs;
paulson@1800
   508
paulson@1800
   509
paulson@2813
   510
fun delI th
oheimb@4651
   511
         (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   512
	           safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   513
 if mem_thm (th, hazIs) then
paulson@2813
   514
     CS{haz_netpair = delete ([th], []) haz_netpair,
paulson@1800
   515
	dup_netpair = delete ([dup_intr th], []) dup_netpair,
paulson@1800
   516
	safeIs 	= safeIs, 
paulson@1800
   517
	safeEs	= safeEs,
paulson@2813
   518
	hazIs	= rem_thm (hazIs,th),
paulson@1800
   519
	hazEs	= hazEs,
oheimb@4651
   520
	swrappers     = swrappers,
oheimb@4651
   521
	uwrappers     = uwrappers,
paulson@1800
   522
	safe0_netpair = safe0_netpair,
paulson@2813
   523
	safep_netpair = safep_netpair}
paulson@2813
   524
 else cs;
paulson@1800
   525
paulson@2813
   526
fun delE th
oheimb@4651
   527
	 (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   528
	           safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   529
 if mem_thm (th, hazEs) then
paulson@2813
   530
     CS{haz_netpair = delete ([], [th]) haz_netpair,
paulson@1800
   531
	dup_netpair = delete ([], [dup_elim th]) dup_netpair,
paulson@1800
   532
	safeIs	= safeIs, 
paulson@1800
   533
	safeEs	= safeEs,
paulson@1800
   534
	hazIs	= hazIs,
paulson@2813
   535
	hazEs	= rem_thm (hazEs,th),
oheimb@4651
   536
	swrappers     = swrappers,
oheimb@4651
   537
	uwrappers     = uwrappers,
paulson@1800
   538
	safe0_netpair = safe0_netpair,
paulson@2813
   539
	safep_netpair = safep_netpair}
paulson@2813
   540
 else cs;
paulson@1800
   541
paulson@2813
   542
(*Delete ALL occurrences of "th" in the claset (perhaps from several lists)*)
paulson@1800
   543
fun delrule (cs as CS{safeIs, safeEs, hazIs, hazEs, ...}, th) =
paulson@2813
   544
       if mem_thm (th, safeIs) orelse mem_thm (th, safeEs) orelse
paulson@2813
   545
	  mem_thm (th, hazIs)  orelse mem_thm (th, hazEs) 
paulson@2813
   546
       then delSI th (delSE th (delI th (delE th cs)))
wenzelm@4079
   547
       else (warning ("Rule not in claset\n" ^ (string_of_thm th)); 
paulson@2813
   548
	     cs);
paulson@1800
   549
paulson@1800
   550
val op delrules = foldl delrule;
paulson@1800
   551
paulson@1800
   552
oheimb@4767
   553
(*** Modifying the wrapper tacticals ***)
oheimb@4767
   554
fun update_swrappers 
oheimb@4767
   555
(CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
oheimb@4767
   556
    safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) f =
oheimb@4767
   557
 CS{safeIs = safeIs, safeEs = safeEs, hazIs = hazIs, hazEs = hazEs,
oheimb@4767
   558
    swrappers = f swrappers, uwrappers = uwrappers,
oheimb@4767
   559
    safe0_netpair = safe0_netpair, safep_netpair = safep_netpair,
oheimb@4767
   560
    haz_netpair = haz_netpair, dup_netpair = dup_netpair};
oheimb@4767
   561
oheimb@4767
   562
fun update_uwrappers 
oheimb@4767
   563
(CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
oheimb@4767
   564
    safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) f =
oheimb@4767
   565
 CS{safeIs = safeIs, safeEs = safeEs, hazIs = hazIs, hazEs = hazEs,
oheimb@4767
   566
    swrappers = swrappers, uwrappers = f uwrappers,
oheimb@4767
   567
    safe0_netpair = safe0_netpair, safep_netpair = safep_netpair,
oheimb@4767
   568
    haz_netpair = haz_netpair, dup_netpair = dup_netpair};
oheimb@4767
   569
lcp@982
   570
oheimb@4651
   571
(*Add/replace a safe wrapper*)
oheimb@4767
   572
fun cs addSWrapper new_swrapper = update_swrappers cs (fn swrappers =>
oheimb@4767
   573
    (case assoc_string (swrappers,(fst new_swrapper)) of None =>()
oheimb@4651
   574
	   | Some x => warning("overwriting safe wrapper "^fst new_swrapper); 
oheimb@4767
   575
		   overwrite (swrappers, new_swrapper)));
oheimb@4651
   576
oheimb@4651
   577
(*Add/replace an unsafe wrapper*)
oheimb@4767
   578
fun cs addWrapper new_uwrapper = update_uwrappers cs (fn uwrappers =>
oheimb@4767
   579
    (case assoc_string (uwrappers,(fst new_uwrapper)) of None =>()
oheimb@4651
   580
	   | Some x => warning ("overwriting unsafe wrapper "^fst new_uwrapper);
oheimb@4767
   581
		   overwrite (uwrappers, new_uwrapper)));
lcp@982
   582
oheimb@4651
   583
(*Remove a safe wrapper*)
oheimb@4767
   584
fun cs delSWrapper name = update_swrappers cs (fn swrappers =>
oheimb@4767
   585
    let val (del,rest) = partition (fn (n,_) => n=name) swrappers
oheimb@4767
   586
    in if null del then (warning ("No such safe wrapper in claset: "^ name); 
oheimb@4767
   587
			 swrappers) else rest end);
lcp@982
   588
oheimb@4651
   589
(*Remove an unsafe wrapper*)
oheimb@4767
   590
fun cs delWrapper name = update_uwrappers cs (fn uwrappers =>
oheimb@4767
   591
    let val (del,rest) = partition (fn (n,_) => n=name) uwrappers
oheimb@4767
   592
    in if null del then (warning ("No such unsafe wrapper in claset: " ^ name);
oheimb@4767
   593
                         uwrappers) else rest end);
lcp@982
   594
oheimb@2630
   595
(*compose a safe tactic sequentially before/alternatively after safe_step_tac*)
oheimb@4767
   596
fun cs addSbefore  (name,    tac1) = 
oheimb@5523
   597
    cs addSWrapper (name, fn tac2 => tac1 ORELSE' tac2);
oheimb@4767
   598
fun cs addSaltern  (name,    tac2) = 
oheimb@5523
   599
    cs addSWrapper (name, fn tac1 => tac1 ORELSE' tac2);
lcp@982
   600
oheimb@2630
   601
(*compose a tactic sequentially before/alternatively after the step tactic*)
oheimb@4767
   602
fun cs addbefore   (name,    tac1) = 
oheimb@5523
   603
    cs addWrapper  (name, fn tac2 => tac1 APPEND' tac2);
oheimb@4767
   604
fun cs addaltern   (name,    tac2) =
oheimb@5523
   605
    cs addWrapper  (name, fn tac1 => tac1 APPEND' tac2);
oheimb@4767
   606
oheimb@5523
   607
fun cs addD2     (name, thm) = 
oheimb@5523
   608
    cs addaltern (name, dtac thm THEN' atac);
oheimb@5523
   609
fun cs addE2     (name, thm) = 
oheimb@5523
   610
    cs addaltern (name, etac thm THEN' atac);
oheimb@5523
   611
fun cs addSD2     (name, thm) = 
oheimb@5523
   612
    cs addSaltern (name, dmatch_tac [thm] THEN' eq_assume_tac);
oheimb@5523
   613
fun cs addSE2     (name, thm) = 
oheimb@5523
   614
    cs addSaltern (name, ematch_tac [thm] THEN' eq_assume_tac);
lcp@982
   615
paulson@1711
   616
(*Merge works by adding all new rules of the 2nd claset into the 1st claset.
paulson@1711
   617
  Merging the term nets may look more efficient, but the rather delicate
paulson@1711
   618
  treatment of priority might get muddled up.*)
paulson@1711
   619
fun merge_cs
oheimb@2630
   620
    (cs as CS{safeIs, safeEs, hazIs, hazEs, ...},
oheimb@4765
   621
     CS{safeIs=safeIs2, safeEs=safeEs2, hazIs=hazIs2, hazEs=hazEs2,
oheimb@4765
   622
	swrappers, uwrappers, ...}) =
paulson@1711
   623
  let val safeIs' = gen_rems eq_thm (safeIs2,safeIs)
paulson@1711
   624
      val safeEs' = gen_rems eq_thm (safeEs2,safeEs)
oheimb@2630
   625
      val  hazIs' = gen_rems eq_thm ( hazIs2, hazIs)
oheimb@2630
   626
      val  hazEs' = gen_rems eq_thm ( hazEs2, hazEs)
oheimb@4767
   627
      val cs1   = cs addSIs safeIs'
oheimb@4765
   628
		     addSEs safeEs'
oheimb@4765
   629
		     addIs  hazIs'
oheimb@4765
   630
		     addEs  hazEs'
oheimb@4767
   631
      val cs2 = update_swrappers cs1 (fn ws => merge_alists ws swrappers);
oheimb@4767
   632
      val cs3 = update_uwrappers cs2 (fn ws => merge_alists ws uwrappers);
oheimb@4767
   633
  in cs3 
paulson@1711
   634
  end;
paulson@1711
   635
lcp@982
   636
paulson@1800
   637
(**** Simple tactics for theorem proving ****)
clasohm@0
   638
clasohm@0
   639
(*Attack subgoals using safe inferences -- matching, not resolution*)
oheimb@2630
   640
fun safe_step_tac (cs as CS{safe0_netpair,safep_netpair,...}) = 
oheimb@4651
   641
  appSWrappers cs (FIRST' [
oheimb@2630
   642
	eq_assume_tac,
oheimb@2630
   643
	eq_mp_tac,
oheimb@2630
   644
	bimatch_from_nets_tac safe0_netpair,
oheimb@2630
   645
	FIRST' hyp_subst_tacs,
oheimb@2630
   646
	bimatch_from_nets_tac safep_netpair]);
clasohm@0
   647
oheimb@5757
   648
(*Repeatedly attack a subgoal using safe inferences -- it's deterministic!*)
oheimb@5757
   649
fun safe_steps_tac cs = REPEAT_DETERM1 o 
oheimb@5757
   650
	(fn i => COND (has_fewer_prems i) no_tac (safe_step_tac cs i));
oheimb@5757
   651
clasohm@0
   652
(*Repeatedly attack subgoals using safe inferences -- it's deterministic!*)
oheimb@5757
   653
fun safe_tac cs = REPEAT_DETERM1 (FIRSTGOAL (safe_steps_tac cs));
lcp@747
   654
paulson@3705
   655
paulson@3705
   656
(*** Clarify_tac: do safe steps without causing branching ***)
paulson@3705
   657
paulson@3705
   658
fun nsubgoalsP n (k,brl) = (subgoals_of_brl brl = n);
paulson@3705
   659
paulson@3705
   660
(*version of bimatch_from_nets_tac that only applies rules that
paulson@3705
   661
  create precisely n subgoals.*)
paulson@3705
   662
fun n_bimatch_from_nets_tac n = 
paulson@3705
   663
    biresolution_from_nets_tac (orderlist o filter (nsubgoalsP n)) true;
paulson@3705
   664
paulson@3705
   665
fun eq_contr_tac i = ematch_tac [not_elim] i  THEN  eq_assume_tac i;
paulson@3705
   666
val eq_assume_contr_tac = eq_assume_tac ORELSE' eq_contr_tac;
paulson@3705
   667
paulson@3705
   668
(*Two-way branching is allowed only if one of the branches immediately closes*)
paulson@3705
   669
fun bimatch2_tac netpair i =
paulson@3705
   670
    n_bimatch_from_nets_tac 2 netpair i THEN
paulson@3705
   671
    (eq_assume_contr_tac i ORELSE eq_assume_contr_tac (i+1));
paulson@3705
   672
paulson@3705
   673
(*Attack subgoals using safe inferences -- matching, not resolution*)
paulson@3705
   674
fun clarify_step_tac (cs as CS{safe0_netpair,safep_netpair,...}) = 
oheimb@4651
   675
  appSWrappers cs (FIRST' [
paulson@3705
   676
	eq_assume_contr_tac,
paulson@3705
   677
	bimatch_from_nets_tac safe0_netpair,
paulson@3705
   678
	FIRST' hyp_subst_tacs,
paulson@3705
   679
	n_bimatch_from_nets_tac 1 safep_netpair,
paulson@3705
   680
        bimatch2_tac safep_netpair]);
paulson@3705
   681
paulson@3705
   682
fun clarify_tac cs = SELECT_GOAL (REPEAT_DETERM (clarify_step_tac cs 1));
paulson@3705
   683
paulson@3705
   684
paulson@3705
   685
(*** Unsafe steps instantiate variables or lose information ***)
paulson@3705
   686
paulson@4066
   687
(*Backtracking is allowed among the various these unsafe ways of
paulson@4066
   688
  proving a subgoal.  *)
lcp@747
   689
fun inst0_step_tac (CS{safe0_netpair,safep_netpair,...}) =
lcp@747
   690
  assume_tac 			  APPEND' 
lcp@747
   691
  contr_tac 			  APPEND' 
lcp@747
   692
  biresolve_from_nets_tac safe0_netpair;
lcp@747
   693
paulson@4066
   694
(*These unsafe steps could generate more subgoals.*)
lcp@747
   695
fun instp_step_tac (CS{safep_netpair,...}) =
lcp@747
   696
  biresolve_from_nets_tac safep_netpair;
clasohm@0
   697
clasohm@0
   698
(*These steps could instantiate variables and are therefore unsafe.*)
lcp@747
   699
fun inst_step_tac cs = inst0_step_tac cs APPEND' instp_step_tac cs;
clasohm@0
   700
lcp@982
   701
fun haz_step_tac (CS{haz_netpair,...}) = 
lcp@681
   702
  biresolve_from_nets_tac haz_netpair;
lcp@681
   703
clasohm@0
   704
(*Single step for the prover.  FAILS unless it makes progress. *)
oheimb@5523
   705
fun step_tac cs i = safe_tac cs ORELSE appWrappers cs 
oheimb@5523
   706
	(inst_step_tac cs ORELSE' haz_step_tac cs) i;
clasohm@0
   707
clasohm@0
   708
(*Using a "safe" rule to instantiate variables is unsafe.  This tactic
clasohm@0
   709
  allows backtracking from "safe" rules to "unsafe" rules here.*)
oheimb@5523
   710
fun slow_step_tac cs i = safe_tac cs ORELSE appWrappers cs 
oheimb@5523
   711
	(inst_step_tac cs APPEND' haz_step_tac cs) i;
clasohm@0
   712
paulson@1800
   713
(**** The following tactics all fail unless they solve one goal ****)
clasohm@0
   714
clasohm@0
   715
(*Dumb but fast*)
clasohm@0
   716
fun fast_tac cs = SELECT_GOAL (DEPTH_SOLVE (step_tac cs 1));
clasohm@0
   717
clasohm@0
   718
(*Slower but smarter than fast_tac*)
clasohm@0
   719
fun best_tac cs = 
clasohm@0
   720
  SELECT_GOAL (BEST_FIRST (has_fewer_prems 1, sizef) (step_tac cs 1));
clasohm@0
   721
clasohm@0
   722
fun slow_tac cs = SELECT_GOAL (DEPTH_SOLVE (slow_step_tac cs 1));
clasohm@0
   723
clasohm@0
   724
fun slow_best_tac cs = 
clasohm@0
   725
  SELECT_GOAL (BEST_FIRST (has_fewer_prems 1, sizef) (slow_step_tac cs 1));
clasohm@0
   726
lcp@681
   727
paulson@1800
   728
(***ASTAR with weight weight_ASTAR, by Norbert Voelker*) 
paulson@1587
   729
val weight_ASTAR = ref 5; 
paulson@1587
   730
paulson@1587
   731
fun astar_tac cs = 
paulson@1587
   732
  SELECT_GOAL ( ASTAR (has_fewer_prems 1
paulson@1587
   733
	      , fn level =>(fn thm =>size_of_thm thm + !weight_ASTAR *level)) 
paulson@1587
   734
	      (step_tac cs 1));
paulson@1587
   735
paulson@1587
   736
fun slow_astar_tac cs = 
paulson@1587
   737
  SELECT_GOAL ( ASTAR (has_fewer_prems 1
paulson@1587
   738
	      , fn level =>(fn thm =>size_of_thm thm + !weight_ASTAR *level)) 
paulson@1587
   739
	      (slow_step_tac cs 1));
paulson@1587
   740
paulson@1800
   741
(**** Complete tactic, loosely based upon LeanTaP.  This tactic is the outcome
lcp@747
   742
  of much experimentation!  Changing APPEND to ORELSE below would prove
lcp@747
   743
  easy theorems faster, but loses completeness -- and many of the harder
paulson@1800
   744
  theorems such as 43. ****)
lcp@681
   745
lcp@747
   746
(*Non-deterministic!  Could always expand the first unsafe connective.
lcp@747
   747
  That's hard to implement and did not perform better in experiments, due to
lcp@747
   748
  greater search depth required.*)
lcp@681
   749
fun dup_step_tac (cs as (CS{dup_netpair,...})) = 
lcp@681
   750
  biresolve_from_nets_tac dup_netpair;
lcp@681
   751
oheimb@5523
   752
(*Searching to depth m. A variant called nodup_depth_tac appears in clasimp.ML*)
oheimb@5757
   753
local
oheimb@5757
   754
fun slow_step_tac' cs = appWrappers cs 
oheimb@5757
   755
	(instp_step_tac cs APPEND' dup_step_tac cs);
oheimb@5757
   756
in fun depth_tac cs m i state = SELECT_GOAL 
oheimb@5757
   757
   (safe_steps_tac cs 1 THEN_ELSE 
oheimb@5757
   758
	(DEPTH_SOLVE (depth_tac cs m 1),
oheimb@5757
   759
	 inst0_step_tac cs 1 APPEND COND (K (m=0)) no_tac
oheimb@5757
   760
		(slow_step_tac' cs 1 THEN DEPTH_SOLVE (depth_tac cs (m-1) 1))
oheimb@5757
   761
        )) i state;
oheimb@5757
   762
end;
lcp@747
   763
paulson@2173
   764
(*Search, with depth bound m.  
paulson@2173
   765
  This is the "entry point", which does safe inferences first.*)
lcp@747
   766
fun safe_depth_tac cs m = 
lcp@681
   767
  SUBGOAL 
lcp@681
   768
    (fn (prem,i) =>
lcp@681
   769
      let val deti =
lcp@681
   770
	  (*No Vars in the goal?  No need to backtrack between goals.*)
lcp@681
   771
	  case term_vars prem of
lcp@681
   772
	      []	=> DETERM 
lcp@681
   773
	    | _::_	=> I
lcp@681
   774
      in  SELECT_GOAL (TRY (safe_tac cs) THEN 
lcp@747
   775
		       DEPTH_SOLVE (deti (depth_tac cs m 1))) i
lcp@747
   776
      end);
lcp@681
   777
paulson@2868
   778
fun deepen_tac cs = DEEPEN (2,10) (safe_depth_tac cs);
lcp@681
   779
wenzelm@4079
   780
berghofe@1724
   781
wenzelm@4079
   782
(** claset theory data **)
wenzelm@4079
   783
wenzelm@4079
   784
(* init data kind claset *)
berghofe@1724
   785
wenzelm@4079
   786
exception CSData of claset ref;
berghofe@1724
   787
wenzelm@4079
   788
local
wenzelm@4079
   789
  val empty = CSData (ref empty_cs);
wenzelm@4079
   790
wenzelm@4079
   791
  (*create new references*)
wenzelm@6556
   792
  fun copy (ClasetData (ref (CSData (ref cs)))) =
wenzelm@4079
   793
    ClasetData (ref (CSData (ref cs)));
wenzelm@6556
   794
  val prep_ext = copy;
berghofe@1724
   795
wenzelm@4079
   796
  fun merge (ClasetData (ref (CSData (ref cs1))), ClasetData (ref (CSData (ref cs2)))) =
wenzelm@4079
   797
    ClasetData (ref (CSData (ref (merge_cs (cs1, cs2)))));
berghofe@1724
   798
wenzelm@4259
   799
  fun print (_: Sign.sg) (ClasetData (ref (CSData (ref cs)))) = print_cs cs;
wenzelm@4079
   800
in
wenzelm@6556
   801
  val _ = fix_methods (empty, copy, prep_ext, merge, print);
wenzelm@4079
   802
end;
wenzelm@4079
   803
berghofe@1724
   804
wenzelm@4079
   805
(* access claset *)
berghofe@1724
   806
wenzelm@5001
   807
val print_claset = Theory.print_data clasetK;
wenzelm@4380
   808
wenzelm@5001
   809
val claset_ref_of_sg = Sign.get_data clasetK (fn ClasetData (ref (CSData r)) => r);
paulson@1807
   810
wenzelm@6391
   811
val claset_ref_of = claset_ref_of_sg o Theory.sign_of;
wenzelm@4079
   812
val claset_of_sg = ! o claset_ref_of_sg;
wenzelm@6391
   813
val claset_of = claset_of_sg o Theory.sign_of;
paulson@1800
   814
wenzelm@6391
   815
fun CLASET tacf state = tacf (claset_of_sg (Thm.sign_of_thm state)) state;
wenzelm@6391
   816
fun CLASET' tacf i state = tacf (claset_of_sg (Thm.sign_of_thm state)) i state;
paulson@3705
   817
wenzelm@5028
   818
val claset = claset_of o Context.the_context;
wenzelm@6391
   819
val claset_ref = claset_ref_of_sg o Theory.sign_of o Context.the_context;
wenzelm@4079
   820
paulson@3705
   821
wenzelm@4079
   822
(* change claset *)
paulson@1800
   823
wenzelm@4079
   824
fun change_claset f x = claset_ref () := (f (claset (), x));
berghofe@1724
   825
wenzelm@4079
   826
val AddDs = change_claset (op addDs);
wenzelm@4079
   827
val AddEs = change_claset (op addEs);
wenzelm@4079
   828
val AddIs = change_claset (op addIs);
wenzelm@4079
   829
val AddSDs = change_claset (op addSDs);
wenzelm@4079
   830
val AddSEs = change_claset (op addSEs);
wenzelm@4079
   831
val AddSIs = change_claset (op addSIs);
wenzelm@4079
   832
val Delrules = change_claset (op delrules);
paulson@3727
   833
wenzelm@4079
   834
wenzelm@5841
   835
(* proof data kind 'Provers/claset' *)
wenzelm@5841
   836
wenzelm@5841
   837
structure LocalClasetArgs =
wenzelm@5841
   838
struct
wenzelm@5841
   839
  val name = "Provers/claset";
wenzelm@5841
   840
  type T = claset;
wenzelm@5841
   841
  val init = claset_of;
wenzelm@5841
   842
  fun print _ cs = print_cs cs;
wenzelm@5841
   843
end;
wenzelm@5841
   844
wenzelm@5841
   845
structure LocalClaset = ProofDataFun(LocalClasetArgs);
wenzelm@5841
   846
val print_local_claset = LocalClaset.print;
wenzelm@5841
   847
val get_local_claset = LocalClaset.get;
wenzelm@5841
   848
val put_local_claset = LocalClaset.put;
wenzelm@5841
   849
wenzelm@5841
   850
wenzelm@5885
   851
(* attributes *)
wenzelm@5885
   852
wenzelm@5885
   853
fun change_global_cs f (thy, th) =
wenzelm@5885
   854
  let val r = claset_ref_of thy
wenzelm@6096
   855
  in r := f (! r, [th]); (thy, th) end;
wenzelm@5885
   856
wenzelm@5885
   857
fun change_local_cs f (ctxt, th) =
wenzelm@6096
   858
  let val cs = f (get_local_claset ctxt, [th])
wenzelm@5885
   859
  in (put_local_claset cs ctxt, th) end;
wenzelm@5885
   860
wenzelm@5885
   861
val haz_dest_global = change_global_cs (op addDs);
wenzelm@5885
   862
val haz_elim_global = change_global_cs (op addEs);
wenzelm@5885
   863
val haz_intro_global = change_global_cs (op addIs);
wenzelm@5885
   864
val safe_dest_global = change_global_cs (op addSDs);
wenzelm@5885
   865
val safe_elim_global = change_global_cs (op addSEs);
wenzelm@5885
   866
val safe_intro_global = change_global_cs (op addSIs);
wenzelm@5885
   867
val delrule_global = change_global_cs (op delrules);
wenzelm@5885
   868
wenzelm@5885
   869
val haz_dest_local = change_local_cs (op addDs);
wenzelm@5885
   870
val haz_elim_local = change_local_cs (op addEs);
wenzelm@5885
   871
val haz_intro_local = change_local_cs (op addIs);
wenzelm@5885
   872
val safe_dest_local = change_local_cs (op addSDs);
wenzelm@5885
   873
val safe_elim_local = change_local_cs (op addSEs);
wenzelm@5885
   874
val safe_intro_local = change_local_cs (op addSIs);
wenzelm@5885
   875
val delrule_local = change_local_cs (op delrules);
wenzelm@5885
   876
wenzelm@5885
   877
wenzelm@4079
   878
(* tactics referring to the implicit claset *)
paulson@1800
   879
wenzelm@4079
   880
(*the abstraction over the proof state delays the dereferencing*)
wenzelm@4079
   881
fun Safe_tac st		  = safe_tac (claset()) st;
wenzelm@4079
   882
fun Safe_step_tac i st	  = safe_step_tac (claset()) i st;
wenzelm@4079
   883
fun Clarify_step_tac i st = clarify_step_tac (claset()) i st;
wenzelm@4079
   884
fun Clarify_tac i st	  = clarify_tac (claset()) i st;
wenzelm@4079
   885
fun Step_tac i st	  = step_tac (claset()) i st;
wenzelm@4079
   886
fun Fast_tac i st	  = fast_tac (claset()) i st;
wenzelm@4079
   887
fun Best_tac i st	  = best_tac (claset()) i st;
wenzelm@4079
   888
fun Slow_tac i st	  = slow_tac (claset()) i st;
wenzelm@4079
   889
fun Slow_best_tac i st	  = slow_best_tac (claset()) i st;
wenzelm@4079
   890
fun Deepen_tac m	  = deepen_tac (claset()) m;
paulson@2066
   891
paulson@1800
   892
clasohm@0
   893
end; 
wenzelm@5841
   894
wenzelm@5841
   895
wenzelm@5841
   896
wenzelm@5885
   897
(** concrete syntax of attributes **)
wenzelm@5841
   898
wenzelm@5841
   899
(* add / del rules *)
wenzelm@5841
   900
wenzelm@5841
   901
val introN = "intro";
wenzelm@5841
   902
val elimN = "elim";
wenzelm@5841
   903
val destN = "dest";
wenzelm@5841
   904
val delN = "del";
wenzelm@5885
   905
val delruleN = "delrule";
wenzelm@5841
   906
wenzelm@5885
   907
val bang = Args.$$$ "!";
wenzelm@5841
   908
wenzelm@5885
   909
fun cla_att change haz safe =
wenzelm@5885
   910
  Attrib.syntax (Scan.lift ((bang >> K haz || Scan.succeed safe) >> change));
wenzelm@5841
   911
wenzelm@5885
   912
fun cla_attr f g = (cla_att change_global_cs f g, cla_att change_local_cs f g);
wenzelm@5885
   913
val del_attr = (Attrib.no_args delrule_global, Attrib.no_args delrule_local);
wenzelm@5841
   914
wenzelm@5841
   915
wenzelm@5841
   916
(* setup_attrs *)
wenzelm@5841
   917
wenzelm@5841
   918
val setup_attrs = Attrib.add_attributes
wenzelm@5885
   919
 [(destN, cla_attr (op addDs) (op addSDs), "destruction rule"),
wenzelm@5885
   920
  (elimN, cla_attr (op addEs) (op addSEs), "elimination rule"),
wenzelm@5885
   921
  (introN, cla_attr (op addIs) (op addSIs), "introduction rule"),
wenzelm@5885
   922
  (delruleN, del_attr, "delete rule")];
wenzelm@5841
   923
wenzelm@5841
   924
wenzelm@5841
   925
wenzelm@5885
   926
(** single rule proof method **)
wenzelm@5841
   927
wenzelm@5841
   928
(* utils *)
wenzelm@5841
   929
wenzelm@5841
   930
fun resolve_from_seq_tac rq i st = Seq.flat (Seq.map (fn r => rtac r i st) rq);
wenzelm@5841
   931
fun order_rules xs = map snd (Tactic.orderlist xs);
wenzelm@5841
   932
wenzelm@5841
   933
fun find_rules concl nets =
wenzelm@5841
   934
  let fun rules_of (inet, _) = order_rules (Net.unify_term inet concl)
wenzelm@5841
   935
  in flat (map rules_of nets) end;
wenzelm@5841
   936
wenzelm@5841
   937
fun find_erules [] _ = []
wenzelm@5841
   938
  | find_erules facts nets =
wenzelm@5841
   939
      let
wenzelm@6502
   940
        fun may_unify net = Net.unify_term net o Logic.strip_assums_concl o #prop o Thm.rep_thm;
wenzelm@5841
   941
        fun erules_of (_, enet) = order_rules (flat (map (may_unify enet) facts));
wenzelm@6502
   942
      in flat (map erules_of nets) end;
wenzelm@5841
   943
wenzelm@5841
   944
wenzelm@5841
   945
(* trace rules *)
wenzelm@5841
   946
wenzelm@5841
   947
val trace_rules = ref false;
wenzelm@5841
   948
wenzelm@5841
   949
fun print_rules rules i =
wenzelm@5841
   950
  if not (! trace_rules) then ()
wenzelm@5841
   951
  else
wenzelm@5841
   952
    Pretty.writeln (Pretty.big_list ("trying standard rule(s) on goal #" ^ string_of_int i ^ ":")
wenzelm@5841
   953
      (map Display.pretty_thm rules));
wenzelm@5841
   954
wenzelm@5841
   955
wenzelm@5841
   956
(* single_tac *)
wenzelm@5841
   957
wenzelm@6502
   958
val imp_elim_netpair = insert (0, 0) ([], [imp_elim]) empty_netpair;
wenzelm@6502
   959
val not_elim_netpair = insert (0, 0) ([], [Data.not_elim]) empty_netpair;
wenzelm@6502
   960
wenzelm@6096
   961
fun single_tac cs facts =
wenzelm@5841
   962
  let
wenzelm@5841
   963
    val CS {safe0_netpair, safep_netpair, haz_netpair, dup_netpair, ...} = cs;
wenzelm@6502
   964
    val nets = [imp_elim_netpair, safe0_netpair, safep_netpair,
wenzelm@6502
   965
      not_elim_netpair, haz_netpair, dup_netpair];
wenzelm@6492
   966
    val erules = find_erules facts nets;
wenzelm@5841
   967
wenzelm@5841
   968
    val tac = SUBGOAL (fn (goal, i) =>
wenzelm@5841
   969
      let
wenzelm@5841
   970
        val irules = find_rules (Logic.strip_assums_concl goal) nets;
wenzelm@5841
   971
        val rules = erules @ irules;
wenzelm@5841
   972
        val ruleq = Method.forward_chain facts rules;
wenzelm@5841
   973
      in
wenzelm@5841
   974
        print_rules rules i;
wenzelm@5841
   975
        fn st => Seq.flat (Seq.map (fn rule => Tactic.rtac rule i st) ruleq) end);
wenzelm@5841
   976
  in tac end;
wenzelm@5841
   977
wenzelm@5841
   978
val single = Method.METHOD (FIRSTGOAL o (fn facts => CLASET' (fn cs => single_tac cs facts)));
wenzelm@5841
   979
wenzelm@5841
   980
wenzelm@5841
   981
wenzelm@6502
   982
(** more proof methods **)
wenzelm@6502
   983
wenzelm@6502
   984
(* contradiction *)
wenzelm@6502
   985
wenzelm@6502
   986
(* FIXME
wenzelm@6502
   987
val contradiction = Method.METHOD (fn facts =>
wenzelm@6502
   988
  Method.FINISHED (ALLGOALS (Method.same_tac facts THEN' (contr_tac ORELSE' assume_tac))));
wenzelm@6502
   989
*)
wenzelm@6502
   990
wenzelm@6502
   991
val contradiction = Method.METHOD (fn facts => FIRSTGOAL (Method.same_tac facts THEN' contr_tac));
wenzelm@6502
   992
wenzelm@6502
   993
wenzelm@6502
   994
(* automatic methods *)
wenzelm@5841
   995
wenzelm@5927
   996
val cla_modifiers =
wenzelm@5927
   997
 [Args.$$$ destN -- bang >> K haz_dest_local,
wenzelm@5927
   998
  Args.$$$ destN >> K safe_dest_local,
wenzelm@5927
   999
  Args.$$$ elimN -- bang >> K haz_elim_local,
wenzelm@5927
  1000
  Args.$$$ elimN >> K safe_elim_local,
wenzelm@5927
  1001
  Args.$$$ introN -- bang >> K haz_intro_local,
wenzelm@5927
  1002
  Args.$$$ introN >> K safe_intro_local,
wenzelm@5927
  1003
  Args.$$$ delN >> K delrule_local];
wenzelm@5927
  1004
wenzelm@5927
  1005
val cla_args = Method.only_sectioned_args cla_modifiers;
wenzelm@5841
  1006
wenzelm@5885
  1007
fun cla_meth tac ctxt = Method.METHOD0 (tac (get_local_claset ctxt));
wenzelm@5885
  1008
fun cla_meth' tac ctxt = Method.METHOD0 (FIRSTGOAL (tac (get_local_claset ctxt)));
wenzelm@5841
  1009
wenzelm@5885
  1010
val cla_method = cla_args o cla_meth;
wenzelm@5885
  1011
val cla_method' = cla_args o cla_meth';
wenzelm@5841
  1012
wenzelm@5841
  1013
wenzelm@5841
  1014
wenzelm@5841
  1015
(** setup_methods **)
wenzelm@5841
  1016
wenzelm@5841
  1017
val setup_methods = Method.add_methods
wenzelm@5841
  1018
 [("single", Method.no_args single, "apply standard rule (single step)"),
wenzelm@5841
  1019
  ("default", Method.no_args single, "apply standard rule (single step)"),
wenzelm@6502
  1020
  ("contradiction", Method.no_args contradiction, "proof by contradiction"),
wenzelm@5885
  1021
  ("safe_tac", cla_method safe_tac, "safe_tac"),
wenzelm@5885
  1022
  ("safe_step", cla_method' safe_step_tac, "step_tac"),
wenzelm@5885
  1023
  ("fast", cla_method' fast_tac, "fast_tac"),
wenzelm@5885
  1024
  ("best", cla_method' best_tac, "best_tac"),
wenzelm@5885
  1025
  ("slow", cla_method' slow_tac, "slow_tac"),
wenzelm@5885
  1026
  ("slow_best", cla_method' slow_best_tac, "slow_best_tac")];
wenzelm@5841
  1027
wenzelm@5841
  1028
wenzelm@5841
  1029
wenzelm@5841
  1030
(** theory setup **)
wenzelm@5841
  1031
wenzelm@5841
  1032
(* FIXME claset theory data *)
wenzelm@5841
  1033
wenzelm@5841
  1034
val setup = [LocalClaset.init, setup_attrs, setup_methods];
wenzelm@5841
  1035
wenzelm@5841
  1036
wenzelm@5841
  1037
end;