src/Provers/classical.ML
author wenzelm
Mon Nov 09 15:49:38 1998 +0100 (1998-11-09 ago)
changeset 5841 d05df8752a8a
parent 5757 0ad476dabbc6
child 5885 6c920d876098
permissions -rw-r--r--
local claset theory data;
intro, elim, dest, del attributes;
single_tac and method;
fast, best etc. methods;
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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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TODO:
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  - only BASIC_CLASSICAL made pervasive;
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  - fix global claset data;
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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) *
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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 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 dest_global: theory attribute
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  val elim_global: theory attribute
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  val 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 delrules_global: theory attribute
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  val dest_local: Proof.context attribute
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  val elim_local: Proof.context attribute
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  val 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 delrules_local: Proof.context attribute
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  val trace_rules: bool ref
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  val single_tac: claset -> tthm 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 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 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, prep_ext, merge, print)];
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  fun fix_methods (e, ext, mrg, prt) =
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    (empty_ref := e; 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_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 = (Net.empty,Net.empty),
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     safep_netpair = (Net.empty,Net.empty),
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     haz_netpair   = (Net.empty,Net.empty),
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     dup_netpair   = (Net.empty,Net.empty)};
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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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     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) =
lcp@1073
   324
      (1000000*subgoals_of_brl brl + k, brl) :: 
lcp@1073
   325
      tag_brls (k+1) brls;
lcp@1073
   326
paulson@1800
   327
fun insert_tagged_list kbrls netpr = foldr insert_tagged_brl (kbrls, netpr);
lcp@1073
   328
lcp@1073
   329
(*Insert into netpair that already has nI intr rules and nE elim rules.
lcp@1073
   330
  Count the intr rules double (to account for swapify).  Negate to give the
lcp@1073
   331
  new insertions the lowest priority.*)
lcp@1073
   332
fun insert (nI,nE) = insert_tagged_list o (tag_brls (~(2*nI+nE))) o joinrules;
lcp@1073
   333
paulson@1800
   334
fun delete_tagged_list brls netpr = foldr delete_tagged_brl (brls, netpr);
lcp@1073
   335
paulson@1800
   336
val delete = delete_tagged_list o joinrules;
paulson@1800
   337
paulson@2813
   338
val mem_thm = gen_mem eq_thm
paulson@2813
   339
and rem_thm = gen_rem eq_thm;
paulson@2813
   340
paulson@1927
   341
(*Warn if the rule is already present ELSEWHERE in the claset.  The addition
paulson@1927
   342
  is still allowed.*)
paulson@1927
   343
fun warn_dup th (CS{safeIs, safeEs, hazIs, hazEs, ...}) = 
paulson@2813
   344
       if mem_thm (th, safeIs) then 
wenzelm@4079
   345
	 warning ("Rule already in claset as Safe Intr\n" ^ string_of_thm th)
paulson@2813
   346
  else if mem_thm (th, safeEs) then
wenzelm@4079
   347
         warning ("Rule already in claset as Safe Elim\n" ^ string_of_thm th)
paulson@2813
   348
  else if mem_thm (th, hazIs) then 
wenzelm@4079
   349
         warning ("Rule already in claset as unsafe Intr\n" ^ string_of_thm th)
paulson@2813
   350
  else if mem_thm (th, hazEs) then 
wenzelm@4079
   351
         warning ("Rule already in claset as unsafe Elim\n" ^ string_of_thm th)
paulson@1927
   352
  else ();
paulson@1927
   353
paulson@1800
   354
(*** Safe rules ***)
lcp@982
   355
oheimb@4651
   356
fun addSI (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   357
	      safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   358
	   th)  =
paulson@2813
   359
  if mem_thm (th, safeIs) then 
wenzelm@4079
   360
	 (warning ("Ignoring duplicate Safe Intr\n" ^ string_of_thm th);
paulson@1927
   361
	  cs)
paulson@1927
   362
  else
lcp@1073
   363
  let val (safe0_rls, safep_rls) = (*0 subgoals vs 1 or more*)
paulson@1927
   364
          partition (fn rl => nprems_of rl=0) [th]
paulson@1927
   365
      val nI = length safeIs + 1
lcp@1073
   366
      and nE = length safeEs
paulson@1927
   367
  in warn_dup th cs;
paulson@1927
   368
     CS{safeIs	= th::safeIs,
lcp@1073
   369
        safe0_netpair = insert (nI,nE) (safe0_rls, []) safe0_netpair,
lcp@1073
   370
	safep_netpair = insert (nI,nE) (safep_rls, []) safep_netpair,
lcp@1073
   371
	safeEs	= safeEs,
lcp@1073
   372
	hazIs	= hazIs,
lcp@1073
   373
	hazEs	= hazEs,
oheimb@4651
   374
	swrappers    = swrappers,
oheimb@4651
   375
	uwrappers    = uwrappers,
oheimb@2630
   376
	haz_netpair  = haz_netpair,
oheimb@2630
   377
	dup_netpair  = dup_netpair}
lcp@1073
   378
  end;
lcp@1073
   379
oheimb@4651
   380
fun addSE (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   381
		    safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   382
	   th)  =
paulson@2813
   383
  if mem_thm (th, safeEs) then 
wenzelm@4079
   384
	 (warning ("Ignoring duplicate Safe Elim\n" ^ string_of_thm th);
paulson@1927
   385
	  cs)
paulson@1927
   386
  else
lcp@1073
   387
  let val (safe0_rls, safep_rls) = (*0 subgoals vs 1 or more*)
paulson@1927
   388
          partition (fn rl => nprems_of rl=1) [th]
lcp@1073
   389
      val nI = length safeIs
paulson@1927
   390
      and nE = length safeEs + 1
paulson@1927
   391
  in warn_dup th cs;
paulson@1927
   392
     CS{safeEs	= th::safeEs,
lcp@1073
   393
        safe0_netpair = insert (nI,nE) ([], safe0_rls) safe0_netpair,
lcp@1073
   394
	safep_netpair = insert (nI,nE) ([], safep_rls) safep_netpair,
lcp@1073
   395
	safeIs	= safeIs,
lcp@1073
   396
	hazIs	= hazIs,
lcp@1073
   397
	hazEs	= hazEs,
oheimb@4651
   398
	swrappers    = swrappers,
oheimb@4651
   399
	uwrappers    = uwrappers,
oheimb@2630
   400
	haz_netpair  = haz_netpair,
oheimb@2630
   401
	dup_netpair  = dup_netpair}
lcp@1073
   402
  end;
clasohm@0
   403
paulson@1927
   404
fun rev_foldl f (e, l) = foldl f (e, rev l);
paulson@1927
   405
paulson@1927
   406
val op addSIs = rev_foldl addSI;
paulson@1927
   407
val op addSEs = rev_foldl addSE;
paulson@1927
   408
clasohm@0
   409
fun cs addSDs ths = cs addSEs (map make_elim ths);
clasohm@0
   410
lcp@1073
   411
paulson@1800
   412
(*** Hazardous (unsafe) rules ***)
clasohm@0
   413
oheimb@4651
   414
fun addI (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   415
		   safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   416
	  th)=
paulson@2813
   417
  if mem_thm (th, hazIs) then 
wenzelm@4079
   418
	 (warning ("Ignoring duplicate unsafe Intr\n" ^ string_of_thm th);
paulson@1927
   419
	  cs)
paulson@1927
   420
  else
paulson@1927
   421
  let val nI = length hazIs + 1
lcp@1073
   422
      and nE = length hazEs
paulson@1927
   423
  in warn_dup th cs;
paulson@1927
   424
     CS{hazIs	= th::hazIs,
paulson@1927
   425
	haz_netpair = insert (nI,nE) ([th], []) haz_netpair,
paulson@1927
   426
	dup_netpair = insert (nI,nE) (map dup_intr [th], []) dup_netpair,
lcp@1073
   427
	safeIs 	= safeIs, 
lcp@1073
   428
	safeEs	= safeEs,
lcp@1073
   429
	hazEs	= hazEs,
oheimb@4651
   430
	swrappers     = swrappers,
oheimb@4651
   431
	uwrappers     = uwrappers,
lcp@1073
   432
	safe0_netpair = safe0_netpair,
lcp@1073
   433
	safep_netpair = safep_netpair}
lcp@1073
   434
  end;
lcp@1073
   435
oheimb@4651
   436
fun addE (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@1927
   437
		   safe0_netpair, safep_netpair, haz_netpair, dup_netpair},
paulson@1927
   438
	  th) =
paulson@2813
   439
  if mem_thm (th, hazEs) then 
wenzelm@4079
   440
	 (warning ("Ignoring duplicate unsafe Elim\n" ^ string_of_thm th);
paulson@1927
   441
	  cs)
paulson@1927
   442
  else
lcp@1073
   443
  let val nI = length hazIs 
paulson@1927
   444
      and nE = length hazEs + 1
paulson@1927
   445
  in warn_dup th cs;
paulson@1927
   446
     CS{hazEs	= th::hazEs,
paulson@1927
   447
	haz_netpair = insert (nI,nE) ([], [th]) haz_netpair,
paulson@1927
   448
	dup_netpair = insert (nI,nE) ([], map dup_elim [th]) dup_netpair,
lcp@1073
   449
	safeIs	= safeIs, 
lcp@1073
   450
	safeEs	= safeEs,
lcp@1073
   451
	hazIs	= hazIs,
oheimb@4651
   452
	swrappers     = swrappers,
oheimb@4651
   453
	uwrappers     = uwrappers,
lcp@1073
   454
	safe0_netpair = safe0_netpair,
lcp@1073
   455
	safep_netpair = safep_netpair}
lcp@1073
   456
  end;
clasohm@0
   457
paulson@1927
   458
val op addIs = rev_foldl addI;
paulson@1927
   459
val op addEs = rev_foldl addE;
paulson@1927
   460
clasohm@0
   461
fun cs addDs ths = cs addEs (map make_elim ths);
clasohm@0
   462
lcp@1073
   463
paulson@1800
   464
(*** Deletion of rules 
paulson@1800
   465
     Working out what to delete, requires repeating much of the code used
paulson@1800
   466
	to insert.
paulson@1927
   467
     Separate functions delSI, etc., are not exported; instead delrules
paulson@2813
   468
        searches in all the lists and chooses the relevant delXX functions.
paulson@1800
   469
***)
paulson@1800
   470
paulson@2813
   471
fun delSI th 
oheimb@4651
   472
          (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   473
		    safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   474
 if mem_thm (th, safeIs) then
paulson@2813
   475
   let val (safe0_rls, safep_rls) = partition (fn rl => nprems_of rl=0) [th]
paulson@2813
   476
   in CS{safe0_netpair = delete (safe0_rls, []) safe0_netpair,
paulson@2813
   477
	 safep_netpair = delete (safep_rls, []) safep_netpair,
paulson@2813
   478
	 safeIs	= rem_thm (safeIs,th),
paulson@2813
   479
	 safeEs	= safeEs,
paulson@2813
   480
	 hazIs	= hazIs,
paulson@2813
   481
	 hazEs	= hazEs,
oheimb@4651
   482
	 swrappers    = swrappers,
oheimb@4651
   483
	 uwrappers    = uwrappers,
paulson@2813
   484
	 haz_netpair  = haz_netpair,
paulson@2813
   485
	 dup_netpair  = dup_netpair}
paulson@2813
   486
   end
paulson@2813
   487
 else cs;
paulson@1800
   488
paulson@2813
   489
fun delSE th
oheimb@4651
   490
          (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   491
	            safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   492
 if mem_thm (th, safeEs) then
paulson@2813
   493
   let val (safe0_rls, safep_rls) = partition (fn rl => nprems_of rl=1) [th]
paulson@2813
   494
   in CS{safe0_netpair = delete ([], safe0_rls) safe0_netpair,
paulson@2813
   495
	 safep_netpair = delete ([], safep_rls) safep_netpair,
paulson@2813
   496
	 safeIs	= safeIs,
paulson@2813
   497
	 safeEs	= rem_thm (safeEs,th),
paulson@2813
   498
	 hazIs	= hazIs,
paulson@2813
   499
	 hazEs	= hazEs,
oheimb@4651
   500
	 swrappers    = swrappers,
oheimb@4651
   501
	 uwrappers    = uwrappers,
paulson@2813
   502
	 haz_netpair  = haz_netpair,
paulson@2813
   503
	 dup_netpair  = dup_netpair}
paulson@2813
   504
   end
paulson@2813
   505
 else cs;
paulson@1800
   506
paulson@1800
   507
paulson@2813
   508
fun delI th
oheimb@4651
   509
         (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   510
	           safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   511
 if mem_thm (th, hazIs) then
paulson@2813
   512
     CS{haz_netpair = delete ([th], []) haz_netpair,
paulson@1800
   513
	dup_netpair = delete ([dup_intr th], []) dup_netpair,
paulson@1800
   514
	safeIs 	= safeIs, 
paulson@1800
   515
	safeEs	= safeEs,
paulson@2813
   516
	hazIs	= rem_thm (hazIs,th),
paulson@1800
   517
	hazEs	= hazEs,
oheimb@4651
   518
	swrappers     = swrappers,
oheimb@4651
   519
	uwrappers     = uwrappers,
paulson@1800
   520
	safe0_netpair = safe0_netpair,
paulson@2813
   521
	safep_netpair = safep_netpair}
paulson@2813
   522
 else cs;
paulson@1800
   523
paulson@2813
   524
fun delE th
oheimb@4651
   525
	 (cs as CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
paulson@2813
   526
	           safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) =
paulson@2813
   527
 if mem_thm (th, hazEs) then
paulson@2813
   528
     CS{haz_netpair = delete ([], [th]) haz_netpair,
paulson@1800
   529
	dup_netpair = delete ([], [dup_elim th]) dup_netpair,
paulson@1800
   530
	safeIs	= safeIs, 
paulson@1800
   531
	safeEs	= safeEs,
paulson@1800
   532
	hazIs	= hazIs,
paulson@2813
   533
	hazEs	= rem_thm (hazEs,th),
oheimb@4651
   534
	swrappers     = swrappers,
oheimb@4651
   535
	uwrappers     = uwrappers,
paulson@1800
   536
	safe0_netpair = safe0_netpair,
paulson@2813
   537
	safep_netpair = safep_netpair}
paulson@2813
   538
 else cs;
paulson@1800
   539
paulson@2813
   540
(*Delete ALL occurrences of "th" in the claset (perhaps from several lists)*)
paulson@1800
   541
fun delrule (cs as CS{safeIs, safeEs, hazIs, hazEs, ...}, th) =
paulson@2813
   542
       if mem_thm (th, safeIs) orelse mem_thm (th, safeEs) orelse
paulson@2813
   543
	  mem_thm (th, hazIs)  orelse mem_thm (th, hazEs) 
paulson@2813
   544
       then delSI th (delSE th (delI th (delE th cs)))
wenzelm@4079
   545
       else (warning ("Rule not in claset\n" ^ (string_of_thm th)); 
paulson@2813
   546
	     cs);
paulson@1800
   547
paulson@1800
   548
val op delrules = foldl delrule;
paulson@1800
   549
paulson@1800
   550
oheimb@4767
   551
(*** Modifying the wrapper tacticals ***)
oheimb@4767
   552
fun update_swrappers 
oheimb@4767
   553
(CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
oheimb@4767
   554
    safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) f =
oheimb@4767
   555
 CS{safeIs = safeIs, safeEs = safeEs, hazIs = hazIs, hazEs = hazEs,
oheimb@4767
   556
    swrappers = f swrappers, uwrappers = uwrappers,
oheimb@4767
   557
    safe0_netpair = safe0_netpair, safep_netpair = safep_netpair,
oheimb@4767
   558
    haz_netpair = haz_netpair, dup_netpair = dup_netpair};
oheimb@4767
   559
oheimb@4767
   560
fun update_uwrappers 
oheimb@4767
   561
(CS{safeIs, safeEs, hazIs, hazEs, swrappers, uwrappers, 
oheimb@4767
   562
    safe0_netpair, safep_netpair, haz_netpair, dup_netpair}) f =
oheimb@4767
   563
 CS{safeIs = safeIs, safeEs = safeEs, hazIs = hazIs, hazEs = hazEs,
oheimb@4767
   564
    swrappers = swrappers, uwrappers = f uwrappers,
oheimb@4767
   565
    safe0_netpair = safe0_netpair, safep_netpair = safep_netpair,
oheimb@4767
   566
    haz_netpair = haz_netpair, dup_netpair = dup_netpair};
oheimb@4767
   567
lcp@982
   568
oheimb@4651
   569
(*Add/replace a safe wrapper*)
oheimb@4767
   570
fun cs addSWrapper new_swrapper = update_swrappers cs (fn swrappers =>
oheimb@4767
   571
    (case assoc_string (swrappers,(fst new_swrapper)) of None =>()
oheimb@4651
   572
	   | Some x => warning("overwriting safe wrapper "^fst new_swrapper); 
oheimb@4767
   573
		   overwrite (swrappers, new_swrapper)));
oheimb@4651
   574
oheimb@4651
   575
(*Add/replace an unsafe wrapper*)
oheimb@4767
   576
fun cs addWrapper new_uwrapper = update_uwrappers cs (fn uwrappers =>
oheimb@4767
   577
    (case assoc_string (uwrappers,(fst new_uwrapper)) of None =>()
oheimb@4651
   578
	   | Some x => warning ("overwriting unsafe wrapper "^fst new_uwrapper);
oheimb@4767
   579
		   overwrite (uwrappers, new_uwrapper)));
lcp@982
   580
oheimb@4651
   581
(*Remove a safe wrapper*)
oheimb@4767
   582
fun cs delSWrapper name = update_swrappers cs (fn swrappers =>
oheimb@4767
   583
    let val (del,rest) = partition (fn (n,_) => n=name) swrappers
oheimb@4767
   584
    in if null del then (warning ("No such safe wrapper in claset: "^ name); 
oheimb@4767
   585
			 swrappers) else rest end);
lcp@982
   586
oheimb@4651
   587
(*Remove an unsafe wrapper*)
oheimb@4767
   588
fun cs delWrapper name = update_uwrappers cs (fn uwrappers =>
oheimb@4767
   589
    let val (del,rest) = partition (fn (n,_) => n=name) uwrappers
oheimb@4767
   590
    in if null del then (warning ("No such unsafe wrapper in claset: " ^ name);
oheimb@4767
   591
                         uwrappers) else rest end);
lcp@982
   592
oheimb@2630
   593
(*compose a safe tactic sequentially before/alternatively after safe_step_tac*)
oheimb@4767
   594
fun cs addSbefore  (name,    tac1) = 
oheimb@5523
   595
    cs addSWrapper (name, fn tac2 => tac1 ORELSE' tac2);
oheimb@4767
   596
fun cs addSaltern  (name,    tac2) = 
oheimb@5523
   597
    cs addSWrapper (name, fn tac1 => tac1 ORELSE' tac2);
lcp@982
   598
oheimb@2630
   599
(*compose a tactic sequentially before/alternatively after the step tactic*)
oheimb@4767
   600
fun cs addbefore   (name,    tac1) = 
oheimb@5523
   601
    cs addWrapper  (name, fn tac2 => tac1 APPEND' tac2);
oheimb@4767
   602
fun cs addaltern   (name,    tac2) =
oheimb@5523
   603
    cs addWrapper  (name, fn tac1 => tac1 APPEND' tac2);
oheimb@4767
   604
oheimb@5523
   605
fun cs addD2     (name, thm) = 
oheimb@5523
   606
    cs addaltern (name, dtac thm THEN' atac);
oheimb@5523
   607
fun cs addE2     (name, thm) = 
oheimb@5523
   608
    cs addaltern (name, etac thm THEN' atac);
oheimb@5523
   609
fun cs addSD2     (name, thm) = 
oheimb@5523
   610
    cs addSaltern (name, dmatch_tac [thm] THEN' eq_assume_tac);
oheimb@5523
   611
fun cs addSE2     (name, thm) = 
oheimb@5523
   612
    cs addSaltern (name, ematch_tac [thm] THEN' eq_assume_tac);
lcp@982
   613
paulson@1711
   614
(*Merge works by adding all new rules of the 2nd claset into the 1st claset.
paulson@1711
   615
  Merging the term nets may look more efficient, but the rather delicate
paulson@1711
   616
  treatment of priority might get muddled up.*)
paulson@1711
   617
fun merge_cs
oheimb@2630
   618
    (cs as CS{safeIs, safeEs, hazIs, hazEs, ...},
oheimb@4765
   619
     CS{safeIs=safeIs2, safeEs=safeEs2, hazIs=hazIs2, hazEs=hazEs2,
oheimb@4765
   620
	swrappers, uwrappers, ...}) =
paulson@1711
   621
  let val safeIs' = gen_rems eq_thm (safeIs2,safeIs)
paulson@1711
   622
      val safeEs' = gen_rems eq_thm (safeEs2,safeEs)
oheimb@2630
   623
      val  hazIs' = gen_rems eq_thm ( hazIs2, hazIs)
oheimb@2630
   624
      val  hazEs' = gen_rems eq_thm ( hazEs2, hazEs)
oheimb@4767
   625
      val cs1   = cs addSIs safeIs'
oheimb@4765
   626
		     addSEs safeEs'
oheimb@4765
   627
		     addIs  hazIs'
oheimb@4765
   628
		     addEs  hazEs'
oheimb@4767
   629
      val cs2 = update_swrappers cs1 (fn ws => merge_alists ws swrappers);
oheimb@4767
   630
      val cs3 = update_uwrappers cs2 (fn ws => merge_alists ws uwrappers);
oheimb@4767
   631
  in cs3 
paulson@1711
   632
  end;
paulson@1711
   633
lcp@982
   634
paulson@1800
   635
(**** Simple tactics for theorem proving ****)
clasohm@0
   636
clasohm@0
   637
(*Attack subgoals using safe inferences -- matching, not resolution*)
oheimb@2630
   638
fun safe_step_tac (cs as CS{safe0_netpair,safep_netpair,...}) = 
oheimb@4651
   639
  appSWrappers cs (FIRST' [
oheimb@2630
   640
	eq_assume_tac,
oheimb@2630
   641
	eq_mp_tac,
oheimb@2630
   642
	bimatch_from_nets_tac safe0_netpair,
oheimb@2630
   643
	FIRST' hyp_subst_tacs,
oheimb@2630
   644
	bimatch_from_nets_tac safep_netpair]);
clasohm@0
   645
oheimb@5757
   646
(*Repeatedly attack a subgoal using safe inferences -- it's deterministic!*)
oheimb@5757
   647
fun safe_steps_tac cs = REPEAT_DETERM1 o 
oheimb@5757
   648
	(fn i => COND (has_fewer_prems i) no_tac (safe_step_tac cs i));
oheimb@5757
   649
clasohm@0
   650
(*Repeatedly attack subgoals using safe inferences -- it's deterministic!*)
oheimb@5757
   651
fun safe_tac cs = REPEAT_DETERM1 (FIRSTGOAL (safe_steps_tac cs));
lcp@747
   652
paulson@3705
   653
paulson@3705
   654
(*** Clarify_tac: do safe steps without causing branching ***)
paulson@3705
   655
paulson@3705
   656
fun nsubgoalsP n (k,brl) = (subgoals_of_brl brl = n);
paulson@3705
   657
paulson@3705
   658
(*version of bimatch_from_nets_tac that only applies rules that
paulson@3705
   659
  create precisely n subgoals.*)
paulson@3705
   660
fun n_bimatch_from_nets_tac n = 
paulson@3705
   661
    biresolution_from_nets_tac (orderlist o filter (nsubgoalsP n)) true;
paulson@3705
   662
paulson@3705
   663
fun eq_contr_tac i = ematch_tac [not_elim] i  THEN  eq_assume_tac i;
paulson@3705
   664
val eq_assume_contr_tac = eq_assume_tac ORELSE' eq_contr_tac;
paulson@3705
   665
paulson@3705
   666
(*Two-way branching is allowed only if one of the branches immediately closes*)
paulson@3705
   667
fun bimatch2_tac netpair i =
paulson@3705
   668
    n_bimatch_from_nets_tac 2 netpair i THEN
paulson@3705
   669
    (eq_assume_contr_tac i ORELSE eq_assume_contr_tac (i+1));
paulson@3705
   670
paulson@3705
   671
(*Attack subgoals using safe inferences -- matching, not resolution*)
paulson@3705
   672
fun clarify_step_tac (cs as CS{safe0_netpair,safep_netpair,...}) = 
oheimb@4651
   673
  appSWrappers cs (FIRST' [
paulson@3705
   674
	eq_assume_contr_tac,
paulson@3705
   675
	bimatch_from_nets_tac safe0_netpair,
paulson@3705
   676
	FIRST' hyp_subst_tacs,
paulson@3705
   677
	n_bimatch_from_nets_tac 1 safep_netpair,
paulson@3705
   678
        bimatch2_tac safep_netpair]);
paulson@3705
   679
paulson@3705
   680
fun clarify_tac cs = SELECT_GOAL (REPEAT_DETERM (clarify_step_tac cs 1));
paulson@3705
   681
paulson@3705
   682
paulson@3705
   683
(*** Unsafe steps instantiate variables or lose information ***)
paulson@3705
   684
paulson@4066
   685
(*Backtracking is allowed among the various these unsafe ways of
paulson@4066
   686
  proving a subgoal.  *)
lcp@747
   687
fun inst0_step_tac (CS{safe0_netpair,safep_netpair,...}) =
lcp@747
   688
  assume_tac 			  APPEND' 
lcp@747
   689
  contr_tac 			  APPEND' 
lcp@747
   690
  biresolve_from_nets_tac safe0_netpair;
lcp@747
   691
paulson@4066
   692
(*These unsafe steps could generate more subgoals.*)
lcp@747
   693
fun instp_step_tac (CS{safep_netpair,...}) =
lcp@747
   694
  biresolve_from_nets_tac safep_netpair;
clasohm@0
   695
clasohm@0
   696
(*These steps could instantiate variables and are therefore unsafe.*)
lcp@747
   697
fun inst_step_tac cs = inst0_step_tac cs APPEND' instp_step_tac cs;
clasohm@0
   698
lcp@982
   699
fun haz_step_tac (CS{haz_netpair,...}) = 
lcp@681
   700
  biresolve_from_nets_tac haz_netpair;
lcp@681
   701
clasohm@0
   702
(*Single step for the prover.  FAILS unless it makes progress. *)
oheimb@5523
   703
fun step_tac cs i = safe_tac cs ORELSE appWrappers cs 
oheimb@5523
   704
	(inst_step_tac cs ORELSE' haz_step_tac cs) i;
clasohm@0
   705
clasohm@0
   706
(*Using a "safe" rule to instantiate variables is unsafe.  This tactic
clasohm@0
   707
  allows backtracking from "safe" rules to "unsafe" rules here.*)
oheimb@5523
   708
fun slow_step_tac cs i = safe_tac cs ORELSE appWrappers cs 
oheimb@5523
   709
	(inst_step_tac cs APPEND' haz_step_tac cs) i;
clasohm@0
   710
paulson@1800
   711
(**** The following tactics all fail unless they solve one goal ****)
clasohm@0
   712
clasohm@0
   713
(*Dumb but fast*)
clasohm@0
   714
fun fast_tac cs = SELECT_GOAL (DEPTH_SOLVE (step_tac cs 1));
clasohm@0
   715
clasohm@0
   716
(*Slower but smarter than fast_tac*)
clasohm@0
   717
fun best_tac cs = 
clasohm@0
   718
  SELECT_GOAL (BEST_FIRST (has_fewer_prems 1, sizef) (step_tac cs 1));
clasohm@0
   719
clasohm@0
   720
fun slow_tac cs = SELECT_GOAL (DEPTH_SOLVE (slow_step_tac cs 1));
clasohm@0
   721
clasohm@0
   722
fun slow_best_tac cs = 
clasohm@0
   723
  SELECT_GOAL (BEST_FIRST (has_fewer_prems 1, sizef) (slow_step_tac cs 1));
clasohm@0
   724
lcp@681
   725
paulson@1800
   726
(***ASTAR with weight weight_ASTAR, by Norbert Voelker*) 
paulson@1587
   727
val weight_ASTAR = ref 5; 
paulson@1587
   728
paulson@1587
   729
fun astar_tac cs = 
paulson@1587
   730
  SELECT_GOAL ( ASTAR (has_fewer_prems 1
paulson@1587
   731
	      , fn level =>(fn thm =>size_of_thm thm + !weight_ASTAR *level)) 
paulson@1587
   732
	      (step_tac cs 1));
paulson@1587
   733
paulson@1587
   734
fun slow_astar_tac cs = 
paulson@1587
   735
  SELECT_GOAL ( ASTAR (has_fewer_prems 1
paulson@1587
   736
	      , fn level =>(fn thm =>size_of_thm thm + !weight_ASTAR *level)) 
paulson@1587
   737
	      (slow_step_tac cs 1));
paulson@1587
   738
paulson@1800
   739
(**** Complete tactic, loosely based upon LeanTaP.  This tactic is the outcome
lcp@747
   740
  of much experimentation!  Changing APPEND to ORELSE below would prove
lcp@747
   741
  easy theorems faster, but loses completeness -- and many of the harder
paulson@1800
   742
  theorems such as 43. ****)
lcp@681
   743
lcp@747
   744
(*Non-deterministic!  Could always expand the first unsafe connective.
lcp@747
   745
  That's hard to implement and did not perform better in experiments, due to
lcp@747
   746
  greater search depth required.*)
lcp@681
   747
fun dup_step_tac (cs as (CS{dup_netpair,...})) = 
lcp@681
   748
  biresolve_from_nets_tac dup_netpair;
lcp@681
   749
oheimb@5523
   750
(*Searching to depth m. A variant called nodup_depth_tac appears in clasimp.ML*)
oheimb@5757
   751
local
oheimb@5757
   752
fun slow_step_tac' cs = appWrappers cs 
oheimb@5757
   753
	(instp_step_tac cs APPEND' dup_step_tac cs);
oheimb@5757
   754
in fun depth_tac cs m i state = SELECT_GOAL 
oheimb@5757
   755
   (safe_steps_tac cs 1 THEN_ELSE 
oheimb@5757
   756
	(DEPTH_SOLVE (depth_tac cs m 1),
oheimb@5757
   757
	 inst0_step_tac cs 1 APPEND COND (K (m=0)) no_tac
oheimb@5757
   758
		(slow_step_tac' cs 1 THEN DEPTH_SOLVE (depth_tac cs (m-1) 1))
oheimb@5757
   759
        )) i state;
oheimb@5757
   760
end;
lcp@747
   761
paulson@2173
   762
(*Search, with depth bound m.  
paulson@2173
   763
  This is the "entry point", which does safe inferences first.*)
lcp@747
   764
fun safe_depth_tac cs m = 
lcp@681
   765
  SUBGOAL 
lcp@681
   766
    (fn (prem,i) =>
lcp@681
   767
      let val deti =
lcp@681
   768
	  (*No Vars in the goal?  No need to backtrack between goals.*)
lcp@681
   769
	  case term_vars prem of
lcp@681
   770
	      []	=> DETERM 
lcp@681
   771
	    | _::_	=> I
lcp@681
   772
      in  SELECT_GOAL (TRY (safe_tac cs) THEN 
lcp@747
   773
		       DEPTH_SOLVE (deti (depth_tac cs m 1))) i
lcp@747
   774
      end);
lcp@681
   775
paulson@2868
   776
fun deepen_tac cs = DEEPEN (2,10) (safe_depth_tac cs);
lcp@681
   777
wenzelm@4079
   778
berghofe@1724
   779
wenzelm@4079
   780
(** claset theory data **)
wenzelm@4079
   781
wenzelm@4079
   782
(* init data kind claset *)
berghofe@1724
   783
wenzelm@4079
   784
exception CSData of claset ref;
berghofe@1724
   785
wenzelm@4079
   786
local
wenzelm@4079
   787
  val empty = CSData (ref empty_cs);
wenzelm@4079
   788
wenzelm@4079
   789
  (*create new references*)
wenzelm@4079
   790
  fun prep_ext (ClasetData (ref (CSData (ref cs)))) =
wenzelm@4079
   791
    ClasetData (ref (CSData (ref cs)));
berghofe@1724
   792
wenzelm@4079
   793
  fun merge (ClasetData (ref (CSData (ref cs1))), ClasetData (ref (CSData (ref cs2)))) =
wenzelm@4079
   794
    ClasetData (ref (CSData (ref (merge_cs (cs1, cs2)))));
berghofe@1724
   795
wenzelm@4259
   796
  fun print (_: Sign.sg) (ClasetData (ref (CSData (ref cs)))) = print_cs cs;
wenzelm@4079
   797
in
wenzelm@4079
   798
  val _ = fix_methods (empty, prep_ext, merge, print);
wenzelm@4079
   799
end;
wenzelm@4079
   800
berghofe@1724
   801
wenzelm@4079
   802
(* access claset *)
berghofe@1724
   803
wenzelm@5001
   804
val print_claset = Theory.print_data clasetK;
wenzelm@4380
   805
wenzelm@5001
   806
val claset_ref_of_sg = Sign.get_data clasetK (fn ClasetData (ref (CSData r)) => r);
paulson@1807
   807
wenzelm@4079
   808
val claset_ref_of = claset_ref_of_sg o sign_of;
wenzelm@4079
   809
val claset_of_sg = ! o claset_ref_of_sg;
wenzelm@4079
   810
val claset_of = claset_of_sg o sign_of;
paulson@1800
   811
wenzelm@4079
   812
fun CLASET tacf state = tacf (claset_of_sg (sign_of_thm state)) state;
wenzelm@4079
   813
fun CLASET' tacf i state = tacf (claset_of_sg (sign_of_thm state)) i state;
paulson@3705
   814
wenzelm@5028
   815
val claset = claset_of o Context.the_context;
wenzelm@5028
   816
val claset_ref = claset_ref_of_sg o sign_of o Context.the_context;
wenzelm@4079
   817
paulson@3705
   818
wenzelm@4079
   819
(* change claset *)
paulson@1800
   820
wenzelm@4079
   821
fun change_claset f x = claset_ref () := (f (claset (), x));
berghofe@1724
   822
wenzelm@4079
   823
val AddDs = change_claset (op addDs);
wenzelm@4079
   824
val AddEs = change_claset (op addEs);
wenzelm@4079
   825
val AddIs = change_claset (op addIs);
wenzelm@4079
   826
val AddSDs = change_claset (op addSDs);
wenzelm@4079
   827
val AddSEs = change_claset (op addSEs);
wenzelm@4079
   828
val AddSIs = change_claset (op addSIs);
wenzelm@4079
   829
val Delrules = change_claset (op delrules);
paulson@3727
   830
wenzelm@4079
   831
wenzelm@5841
   832
(* proof data kind 'Provers/claset' *)
wenzelm@5841
   833
wenzelm@5841
   834
structure LocalClasetArgs =
wenzelm@5841
   835
struct
wenzelm@5841
   836
  val name = "Provers/claset";
wenzelm@5841
   837
  type T = claset;
wenzelm@5841
   838
  val init = claset_of;
wenzelm@5841
   839
  fun print _ cs = print_cs cs;
wenzelm@5841
   840
end;
wenzelm@5841
   841
wenzelm@5841
   842
structure LocalClaset = ProofDataFun(LocalClasetArgs);
wenzelm@5841
   843
val print_local_claset = LocalClaset.print;
wenzelm@5841
   844
val get_local_claset = LocalClaset.get;
wenzelm@5841
   845
val put_local_claset = LocalClaset.put;
wenzelm@5841
   846
wenzelm@5841
   847
wenzelm@4079
   848
(* tactics referring to the implicit claset *)
paulson@1800
   849
wenzelm@4079
   850
(*the abstraction over the proof state delays the dereferencing*)
wenzelm@4079
   851
fun Safe_tac st		  = safe_tac (claset()) st;
wenzelm@4079
   852
fun Safe_step_tac i st	  = safe_step_tac (claset()) i st;
wenzelm@4079
   853
fun Clarify_step_tac i st = clarify_step_tac (claset()) i st;
wenzelm@4079
   854
fun Clarify_tac i st	  = clarify_tac (claset()) i st;
wenzelm@4079
   855
fun Step_tac i st	  = step_tac (claset()) i st;
wenzelm@4079
   856
fun Fast_tac i st	  = fast_tac (claset()) i st;
wenzelm@4079
   857
fun Best_tac i st	  = best_tac (claset()) i st;
wenzelm@4079
   858
fun Slow_tac i st	  = slow_tac (claset()) i st;
wenzelm@4079
   859
fun Slow_best_tac i st	  = slow_best_tac (claset()) i st;
wenzelm@4079
   860
fun Deepen_tac m	  = deepen_tac (claset()) m;
paulson@2066
   861
paulson@1800
   862
clasohm@0
   863
end; 
wenzelm@5841
   864
wenzelm@5841
   865
wenzelm@5841
   866
wenzelm@5841
   867
(** attributes **)
wenzelm@5841
   868
wenzelm@5841
   869
(* add / del rules *)
wenzelm@5841
   870
wenzelm@5841
   871
val introN = "intro";
wenzelm@5841
   872
val elimN = "elim";
wenzelm@5841
   873
val destN = "dest";
wenzelm@5841
   874
val delN = "del";
wenzelm@5841
   875
wenzelm@5841
   876
val addDs' = Attribute.lift_modifier (op addDs);
wenzelm@5841
   877
val addEs' = Attribute.lift_modifier (op addEs);
wenzelm@5841
   878
val addIs' = Attribute.lift_modifier (op addIs);
wenzelm@5841
   879
val addSDs' = Attribute.lift_modifier (op addSDs);
wenzelm@5841
   880
val addSEs' = Attribute.lift_modifier (op addSEs);
wenzelm@5841
   881
val addSIs' = Attribute.lift_modifier (op addSIs);
wenzelm@5841
   882
val delrules' = Attribute.lift_modifier (op delrules);
wenzelm@5841
   883
wenzelm@5841
   884
local
wenzelm@5841
   885
  fun change_global_cs f (thy, tth) =
wenzelm@5841
   886
    let val r = claset_ref_of thy
wenzelm@5841
   887
    in r := f (! r, [tth]); (thy, tth) end;
wenzelm@5841
   888
wenzelm@5841
   889
  fun change_local_cs f (ctxt, tth) =
wenzelm@5841
   890
    let val cs = f (get_local_claset ctxt, [tth])
wenzelm@5841
   891
    in (put_local_claset cs ctxt, tth) end;
wenzelm@5841
   892
wenzelm@5841
   893
  fun cla_att change f g = Attrib.syntax (Args.$$$ "!" >> K f || Scan.succeed g) change;
wenzelm@5841
   894
in
wenzelm@5841
   895
  val dest_global = change_global_cs addDs';
wenzelm@5841
   896
  val elim_global = change_global_cs addEs';
wenzelm@5841
   897
  val intro_global = change_global_cs addIs';
wenzelm@5841
   898
  val safe_dest_global = change_global_cs addDs';
wenzelm@5841
   899
  val safe_elim_global = change_global_cs addEs';
wenzelm@5841
   900
  val safe_intro_global = change_global_cs addIs';
wenzelm@5841
   901
  val delrules_global = change_global_cs delrules';
wenzelm@5841
   902
wenzelm@5841
   903
  val dest_local = change_local_cs addDs';
wenzelm@5841
   904
  val elim_local = change_local_cs addEs';
wenzelm@5841
   905
  val intro_local = change_local_cs addIs';
wenzelm@5841
   906
  val safe_dest_local = change_local_cs addDs';
wenzelm@5841
   907
  val safe_elim_local = change_local_cs addEs';
wenzelm@5841
   908
  val safe_intro_local = change_local_cs addIs';
wenzelm@5841
   909
  val delrules_local = change_local_cs delrules';
wenzelm@5841
   910
wenzelm@5841
   911
  fun cla_attr f g = (cla_att change_global_cs f g, cla_att change_local_cs f g);
wenzelm@5841
   912
  val del_attr = (Attrib.no_args delrules_global, Attrib.no_args delrules_local);
clasohm@0
   913
end;
wenzelm@5841
   914
wenzelm@5841
   915
wenzelm@5841
   916
(* setup_attrs *)
wenzelm@5841
   917
wenzelm@5841
   918
val setup_attrs = Attrib.add_attributes
wenzelm@5841
   919
 [("dest", cla_attr addDs' addSDs', "destruction rule"),
wenzelm@5841
   920
  ("elim", cla_attr addEs' addSEs', "elimination rule"),
wenzelm@5841
   921
  ("intro", cla_attr addIs' addSIs', "introduction rule"),
wenzelm@5841
   922
  ("del", del_attr, "delete rule")];
wenzelm@5841
   923
wenzelm@5841
   924
wenzelm@5841
   925
wenzelm@5841
   926
(** standard 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@5841
   940
        fun may_unify net = Net.unify_term net o #prop o Thm.rep_thm;
wenzelm@5841
   941
        fun erules_of (_, enet) = order_rules (flat (map (may_unify enet) facts));
wenzelm@5841
   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@5841
   958
fun single_tac cs tfacts =
wenzelm@5841
   959
  let
wenzelm@5841
   960
    val CS {safe0_netpair, safep_netpair, haz_netpair, dup_netpair, ...} = cs;
wenzelm@5841
   961
    val facts = map Attribute.thm_of tfacts;
wenzelm@5841
   962
    val nets = [safe0_netpair, safep_netpair, haz_netpair, dup_netpair];
wenzelm@5841
   963
    val erules = find_erules facts nets;
wenzelm@5841
   964
wenzelm@5841
   965
    val tac = SUBGOAL (fn (goal, i) =>
wenzelm@5841
   966
      let
wenzelm@5841
   967
        val irules = find_rules (Logic.strip_assums_concl goal) nets;
wenzelm@5841
   968
        val rules = erules @ irules;
wenzelm@5841
   969
        val ruleq = Method.forward_chain facts rules;
wenzelm@5841
   970
      in
wenzelm@5841
   971
        print_rules rules i;
wenzelm@5841
   972
        fn st => Seq.flat (Seq.map (fn rule => Tactic.rtac rule i st) ruleq) end);
wenzelm@5841
   973
  in tac end;
wenzelm@5841
   974
wenzelm@5841
   975
val single = Method.METHOD (FIRSTGOAL o (fn facts => CLASET' (fn cs => single_tac cs facts)));
wenzelm@5841
   976
wenzelm@5841
   977
wenzelm@5841
   978
wenzelm@5841
   979
(** automatic methods **)
wenzelm@5841
   980
wenzelm@5841
   981
(* FIXME handle "!" *)
wenzelm@5841
   982
wenzelm@5841
   983
fun cla_args meth =
wenzelm@5841
   984
  Method.sectioned_args get_local_claset addIs'
wenzelm@5841
   985
    [(destN, addSDs'), ("unsafe_dest", addDs'),
wenzelm@5841
   986
      (elimN, addSEs'), ("unsafe_elim", addEs'),
wenzelm@5841
   987
      (introN, addSIs'), ("unsafe_intro", addIs'),
wenzelm@5841
   988
      (delN, delrules')] meth;
wenzelm@5841
   989
wenzelm@5841
   990
(* FIXME facts!? (e.g. apply trivial first) *)
wenzelm@5841
   991
fun gen_cla tac = cla_args (fn cs => Method.METHOD0 (tac cs));
wenzelm@5841
   992
fun gen_cla' tac = cla_args (fn cs => Method.METHOD0 (FIRSTGOAL (tac cs)));
wenzelm@5841
   993
wenzelm@5841
   994
wenzelm@5841
   995
wenzelm@5841
   996
(** setup_methods **)
wenzelm@5841
   997
wenzelm@5841
   998
val setup_methods = Method.add_methods
wenzelm@5841
   999
 [("single", Method.no_args single, "apply standard rule (single step)"),
wenzelm@5841
  1000
  ("default", Method.no_args single, "apply standard rule (single step)"),
wenzelm@5841
  1001
  ("safe_tac", gen_cla safe_tac, "safe_tac"),
wenzelm@5841
  1002
  ("safe_step", gen_cla' safe_step_tac, "step_tac"),
wenzelm@5841
  1003
  ("fast", gen_cla' fast_tac, "fast_tac"),
wenzelm@5841
  1004
  ("best", gen_cla' best_tac, "best_tac"),
wenzelm@5841
  1005
  ("slow", gen_cla' slow_tac, "slow_tac"),
wenzelm@5841
  1006
  ("slow_best", gen_cla' slow_best_tac, "slow_best_tac")];
wenzelm@5841
  1007
wenzelm@5841
  1008
wenzelm@5841
  1009
wenzelm@5841
  1010
(** theory setup **)
wenzelm@5841
  1011
wenzelm@5841
  1012
(* FIXME claset theory data *)
wenzelm@5841
  1013
wenzelm@5841
  1014
val setup = [LocalClaset.init, setup_attrs, setup_methods];
wenzelm@5841
  1015
wenzelm@5841
  1016
wenzelm@5841
  1017
end;