src/Pure/meta_simplifier.ML
author wenzelm
Thu Jul 08 19:33:51 2004 +0200 (2004-07-08)
changeset 15023 0e4689f411d5
parent 15011 35be762f58f9
child 15034 e1282c4b39be
permissions -rw-r--r--
major cleanup; got rid of obsolete meta_simpset;
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(*  Title:      Pure/meta_simplifier.ML
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    ID:         $Id$
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    Author:     Tobias Nipkow and Stefan Berghofer
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Meta-level Simplification.
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*)
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infix 4
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  addsimps delsimps addeqcongs deleqcongs addcongs delcongs addsimprocs delsimprocs
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  setmksimps setmkcong setmksym setmkeqTrue settermless setsubgoaler
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  setloop addloop delloop setSSolver addSSolver setSolver addSolver;
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signature BASIC_META_SIMPLIFIER =
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sig
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  val debug_simp: bool ref
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  val trace_simp: bool ref
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  val simp_depth_limit: int ref
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  type rrule
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  type cong
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  type solver
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  val mk_solver: string -> (thm list -> int -> tactic) -> solver
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  type simpset
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  type proc
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  val rep_ss: simpset ->
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   {rules: rrule Net.net,
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    prems: thm list,
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    bounds: string list,
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    depth: int} *
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   {congs: (string * cong) list * string list,
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    procs: proc Net.net,
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    mk_rews:
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     {mk: thm -> thm list,
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      mk_cong: thm -> thm,
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      mk_sym: thm -> thm option,
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      mk_eq_True: thm -> thm option},
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    termless: term * term -> bool,
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    subgoal_tac: simpset -> int -> tactic,
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    loop_tacs: (string * (int -> tactic)) list,
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    solvers: solver list * solver list}
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  val print_ss: simpset -> unit
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  val empty_ss: simpset
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  val merge_ss: simpset * simpset -> simpset
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  type simproc
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  val mk_simproc: string -> cterm list ->
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    (Sign.sg -> simpset -> term -> thm option) -> simproc
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  val add_prems: thm list -> simpset -> simpset
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  val prems_of_ss: simpset -> thm list
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  val addsimps: simpset * thm list -> simpset
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  val delsimps: simpset * thm list -> simpset
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  val addeqcongs: simpset * thm list -> simpset
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  val deleqcongs: simpset * thm list -> simpset
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  val addcongs: simpset * thm list -> simpset
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  val delcongs: simpset * thm list -> simpset
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  val addsimprocs: simpset * simproc list -> simpset
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  val delsimprocs: simpset * simproc list -> simpset
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  val setmksimps: simpset * (thm -> thm list) -> simpset
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  val setmkcong: simpset * (thm -> thm) -> simpset
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  val setmksym: simpset * (thm -> thm option) -> simpset
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  val setmkeqTrue: simpset * (thm -> thm option) -> simpset
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  val settermless: simpset * (term * term -> bool) -> simpset
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  val setsubgoaler: simpset * (simpset -> int -> tactic) -> simpset
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  val setloop: simpset * (int -> tactic) -> simpset
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  val addloop: simpset * (string * (int -> tactic)) -> simpset
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  val delloop: simpset * string -> simpset
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  val setSSolver: simpset * solver -> simpset
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  val addSSolver: simpset * solver -> simpset
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  val setSolver: simpset * solver -> simpset
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  val addSolver: simpset * solver -> simpset
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  val generic_simp_tac: bool -> bool * bool * bool -> simpset -> int -> tactic
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end;
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signature META_SIMPLIFIER =
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sig
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  include BASIC_META_SIMPLIFIER
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  exception SIMPLIFIER of string * thm
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  val dest_ss: simpset ->
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    {simps: thm list, congs: thm list, procs: (string * cterm list) list}
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  val clear_ss: simpset -> simpset
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  exception SIMPROC_FAIL of string * exn
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  val simproc_i: Sign.sg -> string -> term list
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    -> (Sign.sg -> simpset -> term -> thm option) -> simproc
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  val simproc: Sign.sg -> string -> string list
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    -> (Sign.sg -> simpset -> term -> thm option) -> simproc
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  val rewrite_cterm: bool * bool * bool ->
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    (simpset -> thm -> thm option) -> simpset -> cterm -> thm
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  val rewrite_aux: (simpset -> thm -> thm option) -> bool -> thm list -> cterm -> thm
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  val simplify_aux: (simpset -> thm -> thm option) -> bool -> thm list -> thm -> thm
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  val rewrite_term: Sign.sg -> thm list -> (term -> term option) list -> term -> term
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  val rewrite_thm: bool * bool * bool ->
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    (simpset -> thm -> thm option) -> simpset -> thm -> thm
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  val rewrite_goals_rule_aux: (simpset -> thm -> thm option) -> thm list -> thm -> thm
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  val rewrite_goal_rule: bool * bool * bool ->
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    (simpset -> thm -> thm option) -> simpset -> int -> thm -> thm
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  val asm_rewrite_goal_tac: bool * bool * bool ->
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    (simpset -> tactic) -> simpset -> int -> tactic
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  val simp_thm: bool * bool * bool -> simpset -> thm -> thm
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  val simp_cterm: bool * bool * bool -> simpset -> cterm -> thm
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end;
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structure MetaSimplifier: META_SIMPLIFIER =
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struct
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(** diagnostics **)
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exception SIMPLIFIER of string * thm;
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val debug_simp = ref false;
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val trace_simp = ref false;
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val simp_depth = ref 0;
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val simp_depth_limit = ref 1000;
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local
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fun println a =
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  tracing (case ! simp_depth of 0 => a | n => enclose "[" "]" (string_of_int n) ^ a);
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fun prnt warn a = if warn then warning a else println a;
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fun prtm warn a sg t = prnt warn (a ^ "\n" ^ Sign.string_of_term sg t);
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fun prctm warn a t = prnt warn (a ^ "\n" ^ Display.string_of_cterm t);
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in
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fun debug warn a = if ! debug_simp then prnt warn a else ();
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fun trace warn a = if ! trace_simp then prnt warn a else ();
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fun debug_term warn a sign t = if ! debug_simp then prtm warn a sign t else ();
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fun trace_term warn a sign t = if ! trace_simp then prtm warn a sign t else ();
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fun trace_cterm warn a ct = if ! trace_simp then prctm warn a ct else ();
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fun trace_thm a th = if ! trace_simp then prctm false a (Thm.cprop_of th) else ();
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fun trace_named_thm a (thm, name) =
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  if ! trace_simp then
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    prctm false (if name = "" then a else a ^ " " ^ quote name ^ ":") (Thm.cprop_of thm)
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  else ();
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fun warn_thm a = prctm true a o Thm.cprop_of;
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end;
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(** datatype simpset **)
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(* rewrite rules *)
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type rrule = {thm: thm, name: string, lhs: term, elhs: cterm, fo: bool, perm: bool};
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(*thm: the rewrite rule;
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  name: name of theorem from which rewrite rule was extracted;
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  lhs: the left-hand side;
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  elhs: the etac-contracted lhs;
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  fo: use first-order matching;
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  perm: the rewrite rule is permutative;
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Remarks:
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  - elhs is used for matching,
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    lhs only for preservation of bound variable names;
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  - fo is set iff
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    either elhs is first-order (no Var is applied),
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      in which case fo-matching is complete,
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    or elhs is not a pattern,
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      in which case there is nothing better to do;*)
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fun eq_rrule ({thm = thm1, ...}: rrule, {thm = thm2, ...}: rrule) =
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  Drule.eq_thm_prop (thm1, thm2);
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(* congruences *)
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type cong = {thm: thm, lhs: cterm};
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fun eq_cong ({thm = thm1, ...}: cong, {thm = thm2, ...}: cong) =
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  Drule.eq_thm_prop (thm1, thm2);
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(* solvers *)
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datatype solver =
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  Solver of
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   {name: string,
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    solver: thm list -> int -> tactic,
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    id: stamp};
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fun mk_solver name solver = Solver {name = name, solver = solver, id = stamp ()};
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fun solver ths (Solver {solver = tacf, ...}) = tacf ths;
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fun eq_solver (Solver {id = id1, ...}, Solver {id = id2, ...}) = (id1 = id2);
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val merge_solvers = gen_merge_lists eq_solver;
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(* simplification sets and procedures *)
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(*A simpset contains data required during conversion:
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    rules: discrimination net of rewrite rules;
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    prems: current premises;
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    bounds: names of bound variables already used
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      (for generating new names when rewriting under lambda abstractions);
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    depth: depth of conditional rewriting;
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    congs: association list of congruence rules and
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           a list of `weak' congruence constants.
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           A congruence is `weak' if it avoids normalization of some argument.
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    procs: discrimination net of simplification procedures
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      (functions that prove rewrite rules on the fly);
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    mk_rews:
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      mk: turn simplification thms into rewrite rules;
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      mk_cong: prepare congruence rules;
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      mk_sym: turn == around;
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      mk_eq_True: turn P into P == True;
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    termless: relation for ordered rewriting;*)
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type mk_rews =
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 {mk: thm -> thm list,
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  mk_cong: thm -> thm,
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  mk_sym: thm -> thm option,
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  mk_eq_True: thm -> thm option};
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datatype simpset =
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  Simpset of
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   {rules: rrule Net.net,
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    prems: thm list,
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    bounds: string list,
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    depth: int} *
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   {congs: (string * cong) list * string list,
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    procs: proc Net.net,
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    mk_rews: mk_rews,
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    termless: term * term -> bool,
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    subgoal_tac: simpset -> int -> tactic,
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    loop_tacs: (string * (int -> tactic)) list,
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    solvers: solver list * solver list}
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and proc =
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  Proc of
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   {name: string,
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    lhs: cterm,
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    proc: Sign.sg -> simpset -> term -> thm option,
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    id: stamp};
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fun eq_proc (Proc {id = id1, ...}, Proc {id = id2, ...}) = (id1 = id2);
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fun rep_ss (Simpset args) = args;
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fun make_ss1 (rules, prems, bounds, depth) =
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  {rules = rules, prems = prems, bounds = bounds, depth = depth};
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fun map_ss1 f {rules, prems, bounds, depth} =
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  make_ss1 (f (rules, prems, bounds, depth));
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fun make_ss2 (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) =
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  {congs = congs, procs = procs, mk_rews = mk_rews, termless = termless,
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    subgoal_tac = subgoal_tac, loop_tacs = loop_tacs, solvers = solvers};
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fun map_ss2 f {congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers} =
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  make_ss2 (f (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers));
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fun make_simpset (args1, args2) = Simpset (make_ss1 args1, make_ss2 args2);
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fun map_simpset f (Simpset ({rules, prems, bounds, depth},
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    {congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers})) =
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  make_simpset (f ((rules, prems, bounds, depth),
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    (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers)));
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fun map_simpset1 f (Simpset (r1, r2)) = Simpset (map_ss1 f r1, r2);
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fun map_simpset2 f (Simpset (r1, r2)) = Simpset (r1, map_ss2 f r2);
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(* print simpsets *)
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fun dest_ss (Simpset ({rules, ...}, {congs = (congs, _), procs, ...})) =
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  {simps = map (fn (_, {thm, ...}) => thm) (Net.dest rules),
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   congs = map (fn (_, {thm, ...}) => thm) congs,
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   procs =
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     map (fn (_, Proc {name, lhs, id, ...}) => ((name, lhs), id)) (Net.dest procs)
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     |> partition_eq eq_snd
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     |> map (fn ps => (#1 (#1 (hd ps)), map (#2 o #1) ps))
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     |> Library.sort_wrt #1};
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fun print_ss ss =
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  let
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    val {simps, procs, congs} = dest_ss ss;
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    val pretty_thms = map Display.pretty_thm;
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    fun pretty_proc (name, lhss) =
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      Pretty.big_list (name ^ ":") (map Display.pretty_cterm lhss);
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  in
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    [Pretty.big_list "simplification rules:" (pretty_thms simps),
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      Pretty.big_list "simplification procedures:" (map pretty_proc procs),
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      Pretty.big_list "congruences:" (pretty_thms congs)]
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    |> Pretty.chunks |> Pretty.writeln
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  end;
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(* empty simpsets *)
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local
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fun init_ss mk_rews termless subgoal_tac solvers =
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  make_simpset ((Net.empty, [], [], 0),
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    (([], []), Net.empty, mk_rews, termless, subgoal_tac, [], solvers));
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val basic_mk_rews: mk_rews =
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 {mk = fn th => if can Logic.dest_equals (Thm.concl_of th) then [th] else [],
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  mk_cong = I,
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  mk_sym = Some o Drule.symmetric_fun,
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  mk_eq_True = K None};
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in
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val empty_ss = init_ss basic_mk_rews Term.termless (K (K no_tac)) ([], []);
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fun clear_ss (Simpset (_, {mk_rews, termless, subgoal_tac, solvers, ...})) =
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  init_ss mk_rews termless subgoal_tac solvers;
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end;
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(* merge simpsets *)            (*NOTE: ignores some fields of 2nd simpset*)
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fun merge_ss (ss1, ss2) =
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  let
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    val Simpset ({rules = rules1, prems = prems1, bounds = bounds1, depth},
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     {congs = (congs1, weak1), procs = procs1, mk_rews, termless, subgoal_tac,
wenzelm@15023
   323
      loop_tacs = loop_tacs1, solvers = (unsafe_solvers1, solvers1)}) = ss1;
wenzelm@15023
   324
    val Simpset ({rules = rules2, prems = prems2, bounds = bounds2, depth = _},
wenzelm@15023
   325
     {congs = (congs2, weak2), procs = procs2, mk_rews = _, termless = _, subgoal_tac = _,
wenzelm@15023
   326
      loop_tacs = loop_tacs2, solvers = (unsafe_solvers2, solvers2)}) = ss2;
skalberg@15011
   327
wenzelm@15023
   328
    val rules' = Net.merge (rules1, rules2, eq_rrule);
wenzelm@15023
   329
    val prems' = gen_merge_lists Drule.eq_thm_prop prems1 prems2;
wenzelm@15023
   330
    val bounds' = merge_lists bounds1 bounds2;
wenzelm@15023
   331
    val congs' = gen_merge_lists (eq_cong o pairself #2) congs1 congs2;
wenzelm@15023
   332
    val weak' = merge_lists weak1 weak2;
wenzelm@15023
   333
    val procs' = Net.merge (procs1, procs2, eq_proc);
wenzelm@15023
   334
    val loop_tacs' = merge_alists loop_tacs1 loop_tacs2;
wenzelm@15023
   335
    val unsafe_solvers' = merge_solvers unsafe_solvers1 unsafe_solvers2;
wenzelm@15023
   336
    val solvers' = merge_solvers solvers1 solvers2;
wenzelm@15023
   337
  in
wenzelm@15023
   338
    make_simpset ((rules', prems', bounds', depth), ((congs', weak'), procs',
wenzelm@15023
   339
      mk_rews, termless, subgoal_tac, loop_tacs', (unsafe_solvers', solvers')))
wenzelm@15023
   340
  end;
wenzelm@15023
   341
wenzelm@15023
   342
wenzelm@15023
   343
(* simprocs *)
wenzelm@15023
   344
wenzelm@15023
   345
exception SIMPROC_FAIL of string * exn;
wenzelm@15023
   346
wenzelm@15023
   347
datatype simproc = Simproc of proc list;
wenzelm@15023
   348
wenzelm@15023
   349
fun mk_simproc name lhss proc =
wenzelm@15023
   350
  let val id = stamp () in
wenzelm@15023
   351
    Simproc (lhss |> map (fn lhs =>
wenzelm@15023
   352
      Proc {name = name, lhs = lhs, proc = proc, id = id}))
wenzelm@15023
   353
  end;
wenzelm@15023
   354
wenzelm@15023
   355
fun simproc_i sg name = mk_simproc name o map (Thm.cterm_of sg o Logic.varify);
wenzelm@15023
   356
fun simproc sg name = simproc_i sg name o map (Sign.simple_read_term sg TypeInfer.logicT);
wenzelm@15023
   357
skalberg@15011
   358
berghofe@10413
   359
berghofe@10413
   360
(** simpset operations **)
berghofe@10413
   361
wenzelm@15023
   362
(* bounds and prems *)
berghofe@10413
   363
wenzelm@15023
   364
fun add_bound b = map_simpset1 (fn (rules, prems, bounds, depth) =>
wenzelm@15023
   365
  (rules, prems, b :: bounds, depth));
berghofe@10413
   366
wenzelm@15023
   367
fun add_prems ths = map_simpset1 (fn (rules, prems, bounds, depth) =>
wenzelm@15023
   368
  (rules, ths @ prems, bounds, depth));
wenzelm@15023
   369
wenzelm@15023
   370
fun prems_of_ss (Simpset ({prems, ...}, _)) = prems;
berghofe@10413
   371
berghofe@10413
   372
wenzelm@15023
   373
(* addsimps *)
berghofe@10413
   374
wenzelm@15023
   375
fun mk_rrule2 {thm, name, lhs, elhs, perm} =
wenzelm@15023
   376
  let
wenzelm@15023
   377
    val fo = Pattern.first_order (term_of elhs) orelse not (Pattern.pattern (term_of elhs))
wenzelm@15023
   378
  in {thm = thm, name = name, lhs = lhs, elhs = elhs, fo = fo, perm = perm} end;
berghofe@10413
   379
wenzelm@15023
   380
fun insert_rrule quiet (ss, rrule as {thm, name, lhs, elhs, perm}) =
wenzelm@15023
   381
 (trace_named_thm "Adding rewrite rule" (thm, name);
wenzelm@15023
   382
  ss |> map_simpset1 (fn (rules, prems, bounds, depth) =>
wenzelm@15023
   383
    let
wenzelm@15023
   384
      val rrule2 as {elhs, ...} = mk_rrule2 rrule;
wenzelm@15023
   385
      val rules' = Net.insert_term ((term_of elhs, rrule2), rules, eq_rrule);
wenzelm@15023
   386
    in (rules', prems, bounds, depth) end)
wenzelm@15023
   387
  handle Net.INSERT =>
wenzelm@15023
   388
    (if quiet then () else warn_thm "Ignoring duplicate rewrite rule:" thm; ss));
berghofe@10413
   389
berghofe@10413
   390
fun vperm (Var _, Var _) = true
berghofe@10413
   391
  | vperm (Abs (_, _, s), Abs (_, _, t)) = vperm (s, t)
berghofe@10413
   392
  | vperm (t1 $ t2, u1 $ u2) = vperm (t1, u1) andalso vperm (t2, u2)
berghofe@10413
   393
  | vperm (t, u) = (t = u);
berghofe@10413
   394
berghofe@10413
   395
fun var_perm (t, u) =
berghofe@10413
   396
  vperm (t, u) andalso eq_set (term_varnames t, term_varnames u);
berghofe@10413
   397
berghofe@10413
   398
(* FIXME: it seems that the conditions on extra variables are too liberal if
berghofe@10413
   399
prems are nonempty: does solving the prems really guarantee instantiation of
berghofe@10413
   400
all its Vars? Better: a dynamic check each time a rule is applied.
berghofe@10413
   401
*)
berghofe@10413
   402
fun rewrite_rule_extra_vars prems elhs erhs =
berghofe@10413
   403
  not (term_varnames erhs subset foldl add_term_varnames (term_varnames elhs, prems))
berghofe@10413
   404
  orelse
wenzelm@15023
   405
  not (term_tvars erhs subset (term_tvars elhs union List.concat (map term_tvars prems)));
berghofe@10413
   406
wenzelm@15023
   407
(*simple test for looping rewrite rules and stupid orientations*)
berghofe@10413
   408
fun reorient sign prems lhs rhs =
wenzelm@15023
   409
  rewrite_rule_extra_vars prems lhs rhs
wenzelm@15023
   410
    orelse
wenzelm@15023
   411
  is_Var (head_of lhs)
wenzelm@15023
   412
    orelse
wenzelm@15023
   413
  exists (apl (lhs, Logic.occs)) (rhs :: prems)
wenzelm@15023
   414
    orelse
wenzelm@15023
   415
  null prems andalso Pattern.matches (Sign.tsig_of sign) (lhs, rhs)
berghofe@10413
   416
    (*the condition "null prems" is necessary because conditional rewrites
berghofe@10413
   417
      with extra variables in the conditions may terminate although
wenzelm@15023
   418
      the rhs is an instance of the lhs; example: ?m < ?n ==> f(?n) == f(?m)*)
wenzelm@15023
   419
    orelse
wenzelm@15023
   420
  is_Const lhs andalso not (is_Const rhs);
berghofe@10413
   421
berghofe@10413
   422
fun decomp_simp thm =
wenzelm@15023
   423
  let
wenzelm@15023
   424
    val {sign, prop, ...} = Thm.rep_thm thm;
wenzelm@15023
   425
    val prems = Logic.strip_imp_prems prop;
wenzelm@15023
   426
    val concl = Drule.strip_imp_concl (Thm.cprop_of thm);
wenzelm@15023
   427
    val (lhs, rhs) = Drule.dest_equals concl handle TERM _ =>
wenzelm@15023
   428
      raise SIMPLIFIER ("Rewrite rule not a meta-equality", thm);
wenzelm@15023
   429
    val (_, elhs) = Drule.dest_equals (Thm.cprop_of (Thm.eta_conversion lhs));
wenzelm@15023
   430
    val elhs = if elhs = lhs then lhs else elhs;  (*share identical copies*)
wenzelm@15023
   431
    val erhs = Pattern.eta_contract (term_of rhs);
wenzelm@15023
   432
    val perm =
wenzelm@15023
   433
      var_perm (term_of elhs, erhs) andalso
wenzelm@15023
   434
      not (term_of elhs aconv erhs) andalso
wenzelm@15023
   435
      not (is_Var (term_of elhs));
berghofe@10413
   436
  in (sign, prems, term_of lhs, elhs, term_of rhs, perm) end;
berghofe@10413
   437
wenzelm@12783
   438
fun decomp_simp' thm =
wenzelm@12979
   439
  let val (_, _, lhs, _, rhs, _) = decomp_simp thm in
wenzelm@12783
   440
    if Thm.nprems_of thm > 0 then raise SIMPLIFIER ("Bad conditional rewrite rule", thm)
wenzelm@12979
   441
    else (lhs, rhs)
wenzelm@12783
   442
  end;
wenzelm@12783
   443
wenzelm@15023
   444
fun mk_eq_True (Simpset (_, {mk_rews = {mk_eq_True, ...}, ...})) (thm, name) =
wenzelm@15023
   445
  (case mk_eq_True thm of
berghofe@10413
   446
    None => []
berghofe@13607
   447
  | Some eq_True =>
wenzelm@15023
   448
      let val (_, _, lhs, elhs, _, _) = decomp_simp eq_True
wenzelm@15023
   449
      in [{thm = eq_True, name = name, lhs = lhs, elhs = elhs, perm = false}] end);
berghofe@10413
   450
wenzelm@15023
   451
(*create the rewrite rule and possibly also the eq_True variant,
wenzelm@15023
   452
  in case there are extra vars on the rhs*)
wenzelm@15023
   453
fun rrule_eq_True (thm, name, lhs, elhs, rhs, ss, thm2) =
wenzelm@15023
   454
  let val rrule = {thm = thm, name = name, lhs = lhs, elhs = elhs, perm = false} in
wenzelm@15023
   455
    if term_varnames rhs subset term_varnames lhs andalso
wenzelm@15023
   456
      term_tvars rhs subset term_tvars lhs then [rrule]
wenzelm@15023
   457
    else mk_eq_True ss (thm2, name) @ [rrule]
berghofe@10413
   458
  end;
berghofe@10413
   459
wenzelm@15023
   460
fun mk_rrule ss (thm, name) =
wenzelm@15023
   461
  let val (_, prems, lhs, elhs, rhs, perm) = decomp_simp thm in
wenzelm@15023
   462
    if perm then [{thm = thm, name = name, lhs = lhs, elhs = elhs, perm = true}]
wenzelm@15023
   463
    else
wenzelm@15023
   464
      (*weak test for loops*)
wenzelm@15023
   465
      if rewrite_rule_extra_vars prems lhs rhs orelse is_Var (term_of elhs)
wenzelm@15023
   466
      then mk_eq_True ss (thm, name)
wenzelm@15023
   467
      else rrule_eq_True (thm, name, lhs, elhs, rhs, ss, thm)
berghofe@10413
   468
  end;
berghofe@10413
   469
wenzelm@15023
   470
fun orient_rrule ss (thm, name) =
wenzelm@15023
   471
  let val (sign, prems, lhs, elhs, rhs, perm) = decomp_simp thm in
wenzelm@15023
   472
    if perm then [{thm = thm, name = name, lhs = lhs, elhs = elhs, perm = true}]
wenzelm@15023
   473
    else if reorient sign prems lhs rhs then
wenzelm@15023
   474
      if reorient sign prems rhs lhs
wenzelm@15023
   475
      then mk_eq_True ss (thm, name)
wenzelm@15023
   476
      else
wenzelm@15023
   477
        let val Simpset (_, {mk_rews = {mk_sym, ...}, ...}) = ss in
wenzelm@15023
   478
          (case mk_sym thm of
wenzelm@15023
   479
            None => []
wenzelm@15023
   480
          | Some thm' =>
wenzelm@15023
   481
              let val (_, _, lhs', elhs', rhs', _) = decomp_simp thm'
wenzelm@15023
   482
              in rrule_eq_True (thm', name, lhs', elhs', rhs', ss, thm) end)
wenzelm@15023
   483
        end
wenzelm@15023
   484
    else rrule_eq_True (thm, name, lhs, elhs, rhs, ss, thm)
berghofe@10413
   485
  end;
berghofe@10413
   486
wenzelm@15023
   487
fun extract_rews (Simpset (_, {mk_rews = {mk, ...}, ...}), thms) =
berghofe@13607
   488
  flat (map (fn thm => map (rpair (Thm.name_of_thm thm)) (mk thm)) thms);
berghofe@10413
   489
wenzelm@15023
   490
fun orient_comb_simps comb mk_rrule (ss, thms) =
wenzelm@15023
   491
  let
wenzelm@15023
   492
    val rews = extract_rews (ss, thms);
wenzelm@15023
   493
    val rrules = flat (map mk_rrule rews);
wenzelm@15023
   494
  in foldl comb (ss, rrules) end;
berghofe@10413
   495
wenzelm@15023
   496
fun extract_safe_rrules (ss, thm) =
wenzelm@15023
   497
  flat (map (orient_rrule ss) (extract_rews (ss, [thm])));
berghofe@10413
   498
wenzelm@15023
   499
(*add rewrite rules explicitly; do not reorient!*)
wenzelm@15023
   500
fun ss addsimps thms =
wenzelm@15023
   501
  orient_comb_simps (insert_rrule false) (mk_rrule ss) (ss, thms);
berghofe@10413
   502
berghofe@10413
   503
wenzelm@15023
   504
(* delsimps *)
berghofe@10413
   505
wenzelm@15023
   506
fun del_rrule (ss, rrule as {thm, elhs, ...}) =
wenzelm@15023
   507
  ss |> map_simpset1 (fn (rules, prems, bounds, depth) =>
wenzelm@15023
   508
    (Net.delete_term ((term_of elhs, rrule), rules, eq_rrule), prems, bounds, depth))
wenzelm@15023
   509
  handle Net.DELETE => (warn_thm "Rewrite rule not in simpset:" thm; ss);
berghofe@10413
   510
wenzelm@15023
   511
fun ss delsimps thms =
wenzelm@15023
   512
  orient_comb_simps del_rrule (map mk_rrule2 o mk_rrule ss) (ss, thms);
wenzelm@15023
   513
wenzelm@15023
   514
wenzelm@15023
   515
(* congs *)
berghofe@10413
   516
ballarin@13835
   517
fun cong_name (Const (a, _)) = Some a
ballarin@13835
   518
  | cong_name (Free (a, _)) = Some ("Free: " ^ a)
ballarin@13835
   519
  | cong_name _ = None;
ballarin@13835
   520
wenzelm@15023
   521
local
wenzelm@15023
   522
wenzelm@15023
   523
fun is_full_cong_prems [] [] = true
wenzelm@15023
   524
  | is_full_cong_prems [] _ = false
wenzelm@15023
   525
  | is_full_cong_prems (p :: prems) varpairs =
wenzelm@15023
   526
      (case Logic.strip_assums_concl p of
wenzelm@15023
   527
        Const ("==", _) $ lhs $ rhs =>
wenzelm@15023
   528
          let val (x, xs) = strip_comb lhs and (y, ys) = strip_comb rhs in
wenzelm@15023
   529
            is_Var x andalso forall is_Bound xs andalso
wenzelm@15023
   530
            null (findrep xs) andalso xs = ys andalso
wenzelm@15023
   531
            (x, y) mem varpairs andalso
wenzelm@15023
   532
            is_full_cong_prems prems (varpairs \ (x, y))
wenzelm@15023
   533
          end
wenzelm@15023
   534
      | _ => false);
wenzelm@15023
   535
wenzelm@15023
   536
fun is_full_cong thm =
berghofe@10413
   537
  let
wenzelm@15023
   538
    val prems = prems_of thm and concl = concl_of thm;
wenzelm@15023
   539
    val (lhs, rhs) = Logic.dest_equals concl;
wenzelm@15023
   540
    val (f, xs) = strip_comb lhs and (g, ys) = strip_comb rhs;
berghofe@10413
   541
  in
wenzelm@15023
   542
    f = g andalso null (findrep (xs @ ys)) andalso length xs = length ys andalso
wenzelm@15023
   543
    is_full_cong_prems prems (xs ~~ ys)
berghofe@10413
   544
  end;
berghofe@10413
   545
wenzelm@15023
   546
fun add_cong (ss, thm) = ss |>
wenzelm@15023
   547
  map_simpset2 (fn (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   548
    let
wenzelm@15023
   549
      val (lhs, _) = Drule.dest_equals (Drule.strip_imp_concl (Thm.cprop_of thm))
wenzelm@15023
   550
        handle TERM _ => raise SIMPLIFIER ("Congruence not a meta-equality", thm);
wenzelm@15023
   551
    (*val lhs = Pattern.eta_contract lhs;*)
wenzelm@15023
   552
      val a = the (cong_name (head_of (term_of lhs))) handle Library.OPTION =>
wenzelm@15023
   553
        raise SIMPLIFIER ("Congruence must start with a constant or free variable", thm);
wenzelm@15023
   554
      val (alist, weak) = congs;
wenzelm@15023
   555
      val alist2 = overwrite_warn (alist, (a, {lhs = lhs, thm = thm}))
wenzelm@15023
   556
        ("Overwriting congruence rule for " ^ quote a);
wenzelm@15023
   557
      val weak2 = if is_full_cong thm then weak else a :: weak;
wenzelm@15023
   558
    in ((alist2, weak2), procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) end);
berghofe@10413
   559
wenzelm@15023
   560
fun del_cong (ss, thm) = ss |>
wenzelm@15023
   561
  map_simpset2 (fn (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   562
    let
wenzelm@15023
   563
      val (lhs, _) = Logic.dest_equals (Thm.concl_of thm) handle TERM _ =>
wenzelm@15023
   564
        raise SIMPLIFIER ("Congruence not a meta-equality", thm);
wenzelm@15023
   565
    (*val lhs = Pattern.eta_contract lhs;*)
wenzelm@15023
   566
      val a = the (cong_name (head_of lhs)) handle Library.OPTION =>
wenzelm@15023
   567
        raise SIMPLIFIER ("Congruence must start with a constant", thm);
wenzelm@15023
   568
      val (alist, _) = congs;
wenzelm@15023
   569
      val alist2 = filter (fn (x, _) => x <> a) alist;
wenzelm@15023
   570
      val weak2 = alist2 |> mapfilter (fn (a, {thm, ...}) =>
wenzelm@15023
   571
        if is_full_cong thm then None else Some a);
wenzelm@15023
   572
    in ((alist2, weak2), procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) end);
berghofe@10413
   573
wenzelm@15023
   574
fun mk_cong (Simpset (_, {mk_rews = {mk_cong = f, ...}, ...})) = f;
wenzelm@15023
   575
wenzelm@15023
   576
in
wenzelm@15023
   577
wenzelm@15023
   578
val (op addeqcongs) = foldl add_cong;
wenzelm@15023
   579
val (op deleqcongs) = foldl del_cong;
wenzelm@15023
   580
wenzelm@15023
   581
fun ss addcongs congs = ss addeqcongs map (mk_cong ss) congs;
wenzelm@15023
   582
fun ss delcongs congs = ss deleqcongs map (mk_cong ss) congs;
wenzelm@15023
   583
wenzelm@15023
   584
end;
berghofe@10413
   585
berghofe@10413
   586
wenzelm@15023
   587
(* simprocs *)
wenzelm@15023
   588
wenzelm@15023
   589
local
berghofe@10413
   590
wenzelm@15023
   591
fun add_proc (ss, proc as Proc {name, lhs, ...}) =
wenzelm@15023
   592
 (trace_cterm false ("Adding simplification procedure " ^ quote name ^ " for") lhs;
wenzelm@15023
   593
  map_simpset2 (fn (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   594
    (congs, Net.insert_term ((term_of lhs, proc), procs, eq_proc),
wenzelm@15023
   595
      mk_rews, termless, subgoal_tac, loop_tacs, solvers)) ss
wenzelm@15023
   596
  handle Net.INSERT =>
wenzelm@15023
   597
    (warning ("Ignoring duplicate simplification procedure " ^ quote name); ss));
berghofe@10413
   598
wenzelm@15023
   599
fun del_proc (ss, proc as Proc {name, lhs, ...}) =
wenzelm@15023
   600
  map_simpset2 (fn (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   601
    (congs, Net.delete_term ((term_of lhs, proc), procs, eq_proc),
wenzelm@15023
   602
      mk_rews, termless, subgoal_tac, loop_tacs, solvers)) ss
wenzelm@15023
   603
  handle Net.DELETE =>
wenzelm@15023
   604
    (warning ("Simplification procedure " ^ quote name ^ " not in simpset"); ss);
berghofe@10413
   605
wenzelm@15023
   606
in
berghofe@10413
   607
wenzelm@15023
   608
val (op addsimprocs) = foldl (fn (ss, Simproc procs) => foldl add_proc (ss, procs));
wenzelm@15023
   609
val (op delsimprocs) = foldl (fn (ss, Simproc procs) => foldl del_proc (ss, procs));
berghofe@10413
   610
wenzelm@15023
   611
end;
berghofe@10413
   612
berghofe@10413
   613
berghofe@10413
   614
(* mk_rews *)
berghofe@10413
   615
wenzelm@15023
   616
local
wenzelm@15023
   617
wenzelm@15023
   618
fun map_mk_rews f = map_simpset2 (fn (congs, procs, {mk, mk_cong, mk_sym, mk_eq_True},
wenzelm@15023
   619
      termless, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   620
  let val (mk', mk_cong', mk_sym', mk_eq_True') = f (mk, mk_cong, mk_sym, mk_eq_True) in
wenzelm@15023
   621
    (congs, procs, {mk = mk', mk_cong = mk_cong', mk_sym = mk_sym', mk_eq_True = mk_eq_True'},
wenzelm@15023
   622
      termless, subgoal_tac, loop_tacs, solvers)
wenzelm@15023
   623
  end);
wenzelm@15023
   624
wenzelm@15023
   625
in
berghofe@10413
   626
wenzelm@15023
   627
fun ss setmksimps mk = ss |> map_mk_rews (fn (_, mk_cong, mk_sym, mk_eq_True) =>
wenzelm@15023
   628
  (mk, mk_cong, mk_sym, mk_eq_True));
wenzelm@15023
   629
wenzelm@15023
   630
fun ss setmkcong mk_cong = ss |> map_mk_rews (fn (mk, _, mk_sym, mk_eq_True) =>
wenzelm@15023
   631
  (mk, mk_cong, mk_sym, mk_eq_True));
berghofe@10413
   632
wenzelm@15023
   633
fun ss setmksym mk_sym = ss |> map_mk_rews (fn (mk, mk_cong, _, mk_eq_True) =>
wenzelm@15023
   634
  (mk, mk_cong, mk_sym, mk_eq_True));
berghofe@10413
   635
wenzelm@15023
   636
fun ss setmkeqTrue mk_eq_True = ss |> map_mk_rews (fn (mk, mk_cong, mk_sym, _) =>
wenzelm@15023
   637
  (mk, mk_cong, mk_sym, mk_eq_True));
wenzelm@15023
   638
wenzelm@15023
   639
end;
wenzelm@15023
   640
skalberg@14242
   641
berghofe@10413
   642
(* termless *)
berghofe@10413
   643
wenzelm@15023
   644
fun ss settermless termless = ss |>
wenzelm@15023
   645
  map_simpset2 (fn (congs, procs, mk_rews, _, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   646
   (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers));
skalberg@15006
   647
skalberg@15006
   648
wenzelm@15023
   649
(* tactics *)
skalberg@15006
   650
wenzelm@15023
   651
fun ss setsubgoaler subgoal_tac = ss |>
wenzelm@15023
   652
  map_simpset2 (fn (congs, procs, mk_rews, termless, _, loop_tacs, solvers) =>
wenzelm@15023
   653
   (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers));
skalberg@15006
   654
wenzelm@15023
   655
fun ss setloop tac = ss |>
wenzelm@15023
   656
  map_simpset2 (fn (congs, procs, mk_rews, termless, subgoal_tac, _, solvers) =>
wenzelm@15023
   657
   (congs, procs, mk_rews, termless, subgoal_tac, [("", tac)], solvers));
skalberg@15006
   658
wenzelm@15023
   659
fun ss addloop (name, tac) = ss |>
wenzelm@15023
   660
  map_simpset2 (fn (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   661
    (congs, procs, mk_rews, termless, subgoal_tac,
wenzelm@15023
   662
      overwrite_warn (loop_tacs, (name, tac)) ("Overwriting looper " ^ quote name),
wenzelm@15023
   663
      solvers));
skalberg@15006
   664
wenzelm@15023
   665
fun ss delloop name = ss |>
wenzelm@15023
   666
  map_simpset2 (fn (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, solvers) =>
wenzelm@15023
   667
    let val (del, rest) = partition (fn (n, _) => n = name) loop_tacs in
wenzelm@15023
   668
      if null del then warning ("No such looper in simpset: " ^ quote name) else ();
wenzelm@15023
   669
      (congs, procs, mk_rews, termless, subgoal_tac, rest, solvers)
wenzelm@15023
   670
    end);
skalberg@15006
   671
wenzelm@15023
   672
fun ss setSSolver solver = ss |> map_simpset2 (fn (congs, procs, mk_rews, termless,
wenzelm@15023
   673
  subgoal_tac, loop_tacs, (unsafe_solvers, _)) =>
wenzelm@15023
   674
    (congs, procs, mk_rews, termless, subgoal_tac, loop_tacs, (unsafe_solvers, [solver])));
skalberg@15006
   675
wenzelm@15023
   676
fun ss addSSolver solver = ss |> map_simpset2 (fn (congs, procs, mk_rews, termless,
wenzelm@15023
   677
  subgoal_tac, loop_tacs, (unsafe_solvers, solvers)) => (congs, procs, mk_rews, termless,
wenzelm@15023
   678
    subgoal_tac, loop_tacs, (unsafe_solvers, merge_solvers solvers [solver])));
skalberg@15006
   679
wenzelm@15023
   680
fun ss setSolver solver = ss |> map_simpset2 (fn (congs, procs, mk_rews, termless,
wenzelm@15023
   681
  subgoal_tac, loop_tacs, (_, solvers)) => (congs, procs, mk_rews, termless,
wenzelm@15023
   682
    subgoal_tac, loop_tacs, ([solver], solvers)));
skalberg@15006
   683
wenzelm@15023
   684
fun ss addSolver solver = ss |> map_simpset2 (fn (congs, procs, mk_rews, termless,
wenzelm@15023
   685
  subgoal_tac, loop_tacs, (unsafe_solvers, solvers)) => (congs, procs, mk_rews, termless,
wenzelm@15023
   686
    subgoal_tac, loop_tacs, (merge_solvers unsafe_solvers [solver], solvers)));
skalberg@15006
   687
wenzelm@15023
   688
fun set_solvers solvers = map_simpset2 (fn (congs, procs, mk_rews, termless,
wenzelm@15023
   689
  subgoal_tac, loop_tacs, _) => (congs, procs, mk_rews, termless,
wenzelm@15023
   690
  subgoal_tac, loop_tacs, (solvers, solvers)));
skalberg@15006
   691
skalberg@15006
   692
skalberg@15006
   693
berghofe@10413
   694
(** rewriting **)
berghofe@10413
   695
berghofe@10413
   696
(*
berghofe@10413
   697
  Uses conversions, see:
berghofe@10413
   698
    L C Paulson, A higher-order implementation of rewriting,
berghofe@10413
   699
    Science of Computer Programming 3 (1983), pages 119-149.
berghofe@10413
   700
*)
berghofe@10413
   701
wenzelm@15023
   702
val dest_eq = Drule.dest_equals o Thm.cprop_of;
wenzelm@15023
   703
val lhs_of = #1 o dest_eq;
wenzelm@15023
   704
val rhs_of = #2 o dest_eq;
berghofe@10413
   705
berghofe@10413
   706
fun check_conv msg thm thm' =
berghofe@10413
   707
  let
berghofe@10413
   708
    val thm'' = transitive thm (transitive
skalberg@15001
   709
      (symmetric (Drule.beta_eta_conversion (lhs_of thm'))) thm')
wenzelm@15023
   710
  in if msg then trace_thm "SUCCEEDED" thm' else (); Some thm'' end
berghofe@10413
   711
  handle THM _ =>
wenzelm@15023
   712
    let val {sign, prop = _ $ _ $ prop0, ...} = Thm.rep_thm thm in
wenzelm@15023
   713
      trace_thm "Proved wrong thm (Check subgoaler?)" thm';
wenzelm@15023
   714
      trace_term false "Should have proved:" sign prop0;
wenzelm@15023
   715
      None
berghofe@10413
   716
    end;
berghofe@10413
   717
berghofe@10413
   718
berghofe@10413
   719
(* mk_procrule *)
berghofe@10413
   720
berghofe@10413
   721
fun mk_procrule thm =
wenzelm@15023
   722
  let val (_, prems, lhs, elhs, rhs, _) = decomp_simp thm in
wenzelm@15023
   723
    if rewrite_rule_extra_vars prems lhs rhs
wenzelm@15023
   724
    then (warn_thm "Extra vars on rhs:" thm; [])
wenzelm@15023
   725
    else [mk_rrule2 {thm = thm, name = "", lhs = lhs, elhs = elhs, perm = false}]
berghofe@10413
   726
  end;
berghofe@10413
   727
berghofe@10413
   728
wenzelm@15023
   729
(* rewritec: conversion to apply the meta simpset to a term *)
berghofe@10413
   730
wenzelm@15023
   731
(*Since the rewriting strategy is bottom-up, we avoid re-normalizing already
wenzelm@15023
   732
  normalized terms by carrying around the rhs of the rewrite rule just
wenzelm@15023
   733
  applied. This is called the `skeleton'. It is decomposed in parallel
wenzelm@15023
   734
  with the term. Once a Var is encountered, the corresponding term is
wenzelm@15023
   735
  already in normal form.
wenzelm@15023
   736
  skel0 is a dummy skeleton that is to enforce complete normalization.*)
wenzelm@15023
   737
berghofe@10413
   738
val skel0 = Bound 0;
berghofe@10413
   739
wenzelm@15023
   740
(*Use rhs as skeleton only if the lhs does not contain unnormalized bits.
wenzelm@15023
   741
  The latter may happen iff there are weak congruence rules for constants
wenzelm@15023
   742
  in the lhs.*)
berghofe@10413
   743
wenzelm@15023
   744
fun uncond_skel ((_, weak), (lhs, rhs)) =
wenzelm@15023
   745
  if null weak then rhs  (*optimization*)
wenzelm@15023
   746
  else if exists_Const (fn (c, _) => c mem weak) lhs then skel0
wenzelm@15023
   747
  else rhs;
wenzelm@15023
   748
wenzelm@15023
   749
(*Behaves like unconditional rule if rhs does not contain vars not in the lhs.
wenzelm@15023
   750
  Otherwise those vars may become instantiated with unnormalized terms
wenzelm@15023
   751
  while the premises are solved.*)
wenzelm@15023
   752
wenzelm@15023
   753
fun cond_skel (args as (congs, (lhs, rhs))) =
wenzelm@15023
   754
  if term_varnames rhs subset term_varnames lhs then uncond_skel args
berghofe@10413
   755
  else skel0;
berghofe@10413
   756
wenzelm@15023
   757
fun incr_depth ss =
wenzelm@15023
   758
  let
wenzelm@15023
   759
    val ss' = ss |> map_simpset1 (fn (rules, prems, bounds, depth) =>
wenzelm@15023
   760
      (rules, prems, bounds, depth + 1));
wenzelm@15023
   761
    val Simpset ({depth = depth', ...}, _) = ss';
wenzelm@15023
   762
  in
wenzelm@15023
   763
    if depth' > ! simp_depth_limit
wenzelm@15023
   764
    then (warning "simp_depth_limit exceeded - giving up"; None)
wenzelm@15023
   765
    else
wenzelm@15023
   766
     (if depth' mod 10 = 0
wenzelm@15023
   767
      then warning ("Simplification depth " ^ string_of_int depth')
wenzelm@15023
   768
      else ();
wenzelm@15023
   769
      Some ss')
wenzelm@15023
   770
  end;
wenzelm@15023
   771
berghofe@10413
   772
(*
wenzelm@15023
   773
  Rewriting -- we try in order:
berghofe@10413
   774
    (1) beta reduction
berghofe@10413
   775
    (2) unconditional rewrite rules
berghofe@10413
   776
    (3) conditional rewrite rules
berghofe@10413
   777
    (4) simplification procedures
berghofe@10413
   778
berghofe@10413
   779
  IMPORTANT: rewrite rules must not introduce new Vars or TVars!
berghofe@10413
   780
*)
berghofe@10413
   781
wenzelm@15023
   782
fun rewritec (prover, signt, maxt) ss t =
berghofe@10413
   783
  let
wenzelm@15023
   784
    val Simpset ({rules, ...}, {congs, procs, termless, ...}) = ss;
berghofe@10413
   785
    val eta_thm = Thm.eta_conversion t;
berghofe@10413
   786
    val eta_t' = rhs_of eta_thm;
berghofe@10413
   787
    val eta_t = term_of eta_t';
berghofe@10413
   788
    val tsigt = Sign.tsig_of signt;
berghofe@13607
   789
    fun rew {thm, name, lhs, elhs, fo, perm} =
berghofe@10413
   790
      let
berghofe@10413
   791
        val {sign, prop, maxidx, ...} = rep_thm thm;
berghofe@10413
   792
        val _ = if Sign.subsig (sign, signt) then ()
wenzelm@15023
   793
                else (warn_thm "Ignoring rewrite rule from different theory:" thm;
berghofe@10413
   794
                      raise Pattern.MATCH);
berghofe@10413
   795
        val (rthm, elhs') = if maxt = ~1 then (thm, elhs)
berghofe@10413
   796
          else (Thm.incr_indexes (maxt+1) thm, Thm.cterm_incr_indexes (maxt+1) elhs);
berghofe@10413
   797
        val insts = if fo then Thm.cterm_first_order_match (elhs', eta_t')
berghofe@10413
   798
                          else Thm.cterm_match (elhs', eta_t');
berghofe@10413
   799
        val thm' = Thm.instantiate insts (Thm.rename_boundvars lhs eta_t rthm);
wenzelm@14643
   800
        val prop' = Thm.prop_of thm';
berghofe@10413
   801
        val unconditional = (Logic.count_prems (prop',0) = 0);
berghofe@10413
   802
        val (lhs', rhs') = Logic.dest_equals (Logic.strip_imp_concl prop')
berghofe@10413
   803
      in
nipkow@11295
   804
        if perm andalso not (termless (rhs', lhs'))
berghofe@13607
   805
        then (trace_named_thm "Cannot apply permutative rewrite rule" (thm, name);
nipkow@13569
   806
              trace_thm "Term does not become smaller:" thm'; None)
berghofe@13607
   807
        else (trace_named_thm "Applying instance of rewrite rule" (thm, name);
berghofe@10413
   808
           if unconditional
berghofe@10413
   809
           then
nipkow@13569
   810
             (trace_thm "Rewriting:" thm';
berghofe@10413
   811
              let val lr = Logic.dest_equals prop;
berghofe@10413
   812
                  val Some thm'' = check_conv false eta_thm thm'
berghofe@10413
   813
              in Some (thm'', uncond_skel (congs, lr)) end)
berghofe@10413
   814
           else
nipkow@13569
   815
             (trace_thm "Trying to rewrite:" thm';
wenzelm@15023
   816
              case incr_depth ss of
nipkow@13828
   817
                None => (trace_thm "FAILED - reached depth limit" thm'; None)
wenzelm@15023
   818
              | Some ss' =>
wenzelm@15023
   819
              (case prover ss' thm' of
wenzelm@15023
   820
                None => (trace_thm "FAILED" thm'; None)
berghofe@10413
   821
              | Some thm2 =>
berghofe@10413
   822
                  (case check_conv true eta_thm thm2 of
berghofe@10413
   823
                     None => None |
berghofe@10413
   824
                     Some thm2' =>
berghofe@10413
   825
                       let val concl = Logic.strip_imp_concl prop
berghofe@10413
   826
                           val lr = Logic.dest_equals concl
nipkow@13828
   827
                       in Some (thm2', cond_skel (congs, lr)) end))))
berghofe@10413
   828
      end
berghofe@10413
   829
berghofe@10413
   830
    fun rews [] = None
berghofe@10413
   831
      | rews (rrule :: rrules) =
berghofe@10413
   832
          let val opt = rew rrule handle Pattern.MATCH => None
berghofe@10413
   833
          in case opt of None => rews rrules | some => some end;
berghofe@10413
   834
berghofe@10413
   835
    fun sort_rrules rrs = let
wenzelm@14643
   836
      fun is_simple({thm, ...}:rrule) = case Thm.prop_of thm of
berghofe@10413
   837
                                      Const("==",_) $ _ $ _ => true
wenzelm@12603
   838
                                      | _                   => false
berghofe@10413
   839
      fun sort []        (re1,re2) = re1 @ re2
wenzelm@12603
   840
        | sort (rr::rrs) (re1,re2) = if is_simple rr
berghofe@10413
   841
                                     then sort rrs (rr::re1,re2)
berghofe@10413
   842
                                     else sort rrs (re1,rr::re2)
berghofe@10413
   843
    in sort rrs ([],[]) end
berghofe@10413
   844
wenzelm@15023
   845
    fun proc_rews [] = None
wenzelm@15023
   846
      | proc_rews (Proc {name, proc, lhs, ...} :: ps) =
wenzelm@15023
   847
          if Pattern.matches tsigt (Thm.term_of lhs, Thm.term_of t) then
berghofe@10413
   848
            (debug_term false ("Trying procedure " ^ quote name ^ " on:") signt eta_t;
wenzelm@13486
   849
             case transform_failure (curry SIMPROC_FAIL name)
wenzelm@15023
   850
                 (fn () => proc signt ss eta_t) () of
wenzelm@13486
   851
               None => (debug false "FAILED"; proc_rews ps)
wenzelm@13486
   852
             | Some raw_thm =>
nipkow@13569
   853
                 (trace_thm ("Procedure " ^ quote name ^ " produced rewrite rule:") raw_thm;
berghofe@10413
   854
                  (case rews (mk_procrule raw_thm) of
wenzelm@13486
   855
                    None => (trace_cterm true ("IGNORED result of simproc " ^ quote name ^
wenzelm@13486
   856
                      " -- does not match") t; proc_rews ps)
berghofe@10413
   857
                  | some => some)))
berghofe@10413
   858
          else proc_rews ps;
berghofe@10413
   859
  in case eta_t of
berghofe@10413
   860
       Abs _ $ _ => Some (transitive eta_thm
berghofe@12155
   861
         (beta_conversion false eta_t'), skel0)
berghofe@10413
   862
     | _ => (case rews (sort_rrules (Net.match_term rules eta_t)) of
berghofe@10413
   863
               None => proc_rews (Net.match_term procs eta_t)
berghofe@10413
   864
             | some => some)
berghofe@10413
   865
  end;
berghofe@10413
   866
berghofe@10413
   867
berghofe@10413
   868
(* conversion to apply a congruence rule to a term *)
berghofe@10413
   869
berghofe@10413
   870
fun congc (prover,signt,maxt) {thm=cong,lhs=lhs} t =
wenzelm@14643
   871
  let val sign = Thm.sign_of_thm cong
berghofe@10413
   872
      val _ = if Sign.subsig (sign, signt) then ()
berghofe@10413
   873
                 else error("Congruence rule from different theory")
berghofe@10413
   874
      val rthm = if maxt = ~1 then cong else Thm.incr_indexes (maxt+1) cong;
berghofe@10413
   875
      val rlhs = fst (Drule.dest_equals (Drule.strip_imp_concl (cprop_of rthm)));
berghofe@10413
   876
      val insts = Thm.cterm_match (rlhs, t)
berghofe@10413
   877
      (* Pattern.match can raise Pattern.MATCH;
berghofe@10413
   878
         is handled when congc is called *)
berghofe@10413
   879
      val thm' = Thm.instantiate insts (Thm.rename_boundvars (term_of rlhs) (term_of t) rthm);
nipkow@13569
   880
      val unit = trace_thm "Applying congruence rule:" thm';
ballarin@13932
   881
      fun err (msg, thm) = (trace_thm msg thm; None)
berghofe@10413
   882
  in case prover thm' of
ballarin@13932
   883
       None => err ("Congruence proof failed.  Could not prove", thm')
skalberg@15001
   884
     | Some thm2 => (case check_conv true (Drule.beta_eta_conversion t) thm2 of
ballarin@13932
   885
          None => err ("Congruence proof failed.  Should not have proved", thm2)
berghofe@12155
   886
        | Some thm2' =>
berghofe@12155
   887
            if op aconv (pairself term_of (dest_equals (cprop_of thm2')))
berghofe@12155
   888
            then None else Some thm2')
berghofe@10413
   889
  end;
berghofe@10413
   890
berghofe@10413
   891
val (cA, (cB, cC)) =
berghofe@10413
   892
  apsnd dest_equals (dest_implies (hd (cprems_of Drule.imp_cong)));
berghofe@10413
   893
berghofe@13607
   894
fun transitive1 None None = None
berghofe@13607
   895
  | transitive1 (Some thm1) None = Some thm1
berghofe@13607
   896
  | transitive1 None (Some thm2) = Some thm2
berghofe@13607
   897
  | transitive1 (Some thm1) (Some thm2) = Some (transitive thm1 thm2)
berghofe@10413
   898
berghofe@13607
   899
fun transitive2 thm = transitive1 (Some thm);
berghofe@13607
   900
fun transitive3 thm = transitive1 thm o Some;
berghofe@13607
   901
wenzelm@15023
   902
fun bottomc ((simprem, useprem, mutsimp), prover, sign, maxidx) =
berghofe@10413
   903
  let
wenzelm@15023
   904
    fun botc skel ss t =
berghofe@10413
   905
          if is_Var skel then None
berghofe@10413
   906
          else
wenzelm@15023
   907
          (case subc skel ss t of
berghofe@10413
   908
             some as Some thm1 =>
wenzelm@15023
   909
               (case rewritec (prover, sign, maxidx) ss (rhs_of thm1) of
berghofe@10413
   910
                  Some (thm2, skel2) =>
berghofe@13607
   911
                    transitive2 (transitive thm1 thm2)
wenzelm@15023
   912
                      (botc skel2 ss (rhs_of thm2))
berghofe@10413
   913
                | None => some)
berghofe@10413
   914
           | None =>
wenzelm@15023
   915
               (case rewritec (prover, sign, maxidx) ss t of
berghofe@13607
   916
                  Some (thm2, skel2) => transitive2 thm2
wenzelm@15023
   917
                    (botc skel2 ss (rhs_of thm2))
berghofe@10413
   918
                | None => None))
berghofe@10413
   919
wenzelm@15023
   920
    and try_botc ss t =
wenzelm@15023
   921
          (case botc skel0 ss t of
berghofe@10413
   922
             Some trec1 => trec1 | None => (reflexive t))
berghofe@10413
   923
wenzelm@15023
   924
    and subc skel (ss as Simpset ({bounds, ...}, {congs, ...})) t0 =
berghofe@10413
   925
       (case term_of t0 of
berghofe@10413
   926
           Abs (a, T, t) =>
wenzelm@15023
   927
             let
wenzelm@15023
   928
                 val b = variant bounds a;
wenzelm@15023
   929
                 val (v, t') = Thm.dest_abs (Some ("." ^ b)) t0;
wenzelm@15023
   930
                 val ss' = add_bound b ss;
wenzelm@15023
   931
                 val skel' = case skel of Abs (_, _, sk) => sk | _ => skel0;
wenzelm@15023
   932
             in case botc skel' ss' t' of
berghofe@10413
   933
                  Some thm => Some (abstract_rule a v thm)
berghofe@10413
   934
                | None => None
berghofe@10413
   935
             end
berghofe@10413
   936
         | t $ _ => (case t of
wenzelm@15023
   937
             Const ("==>", _) $ _  => impc t0 ss
berghofe@10413
   938
           | Abs _ =>
berghofe@10413
   939
               let val thm = beta_conversion false t0
wenzelm@15023
   940
               in case subc skel0 ss (rhs_of thm) of
berghofe@10413
   941
                    None => Some thm
berghofe@10413
   942
                  | Some thm' => Some (transitive thm thm')
berghofe@10413
   943
               end
berghofe@10413
   944
           | _  =>
berghofe@10413
   945
               let fun appc () =
berghofe@10413
   946
                     let
berghofe@10413
   947
                       val (tskel, uskel) = case skel of
berghofe@10413
   948
                           tskel $ uskel => (tskel, uskel)
berghofe@10413
   949
                         | _ => (skel0, skel0);
wenzelm@10767
   950
                       val (ct, cu) = Thm.dest_comb t0
berghofe@10413
   951
                     in
wenzelm@15023
   952
                     (case botc tskel ss ct of
berghofe@10413
   953
                        Some thm1 =>
wenzelm@15023
   954
                          (case botc uskel ss cu of
berghofe@10413
   955
                             Some thm2 => Some (combination thm1 thm2)
berghofe@10413
   956
                           | None => Some (combination thm1 (reflexive cu)))
berghofe@10413
   957
                      | None =>
wenzelm@15023
   958
                          (case botc uskel ss cu of
berghofe@10413
   959
                             Some thm1 => Some (combination (reflexive ct) thm1)
berghofe@10413
   960
                           | None => None))
berghofe@10413
   961
                     end
berghofe@10413
   962
                   val (h, ts) = strip_comb t
ballarin@13835
   963
               in case cong_name h of
ballarin@13835
   964
                    Some a =>
berghofe@10413
   965
                      (case assoc_string (fst congs, a) of
berghofe@10413
   966
                         None => appc ()
berghofe@10413
   967
                       | Some cong =>
wenzelm@15023
   968
  (*post processing: some partial applications h t1 ... tj, j <= length ts,
wenzelm@15023
   969
    may be a redex. Example: map (%x. x) = (%xs. xs) wrt map_cong*)
berghofe@10413
   970
                          (let
wenzelm@15023
   971
                             val thm = congc (prover ss, sign, maxidx) cong t0;
berghofe@12155
   972
                             val t = if_none (apsome rhs_of thm) t0;
wenzelm@10767
   973
                             val (cl, cr) = Thm.dest_comb t
berghofe@10413
   974
                             val dVar = Var(("", 0), dummyT)
berghofe@10413
   975
                             val skel =
berghofe@10413
   976
                               list_comb (h, replicate (length ts) dVar)
wenzelm@15023
   977
                           in case botc skel ss cl of
berghofe@12155
   978
                                None => thm
berghofe@13607
   979
                              | Some thm' => transitive3 thm
berghofe@12155
   980
                                  (combination thm' (reflexive cr))
berghofe@10413
   981
                           end handle TERM _ => error "congc result"
berghofe@10413
   982
                                    | Pattern.MATCH => appc ()))
berghofe@10413
   983
                  | _ => appc ()
berghofe@10413
   984
               end)
berghofe@10413
   985
         | _ => None)
berghofe@10413
   986
wenzelm@15023
   987
    and impc ct ss =
wenzelm@15023
   988
      if mutsimp then mut_impc0 [] ct [] [] ss else nonmut_impc ct ss
berghofe@10413
   989
wenzelm@15023
   990
    and rules_of_prem ss prem =
berghofe@13607
   991
      if maxidx_of_term (term_of prem) <> ~1
berghofe@13607
   992
      then (trace_cterm true
berghofe@13607
   993
        "Cannot add premise as rewrite rule because it contains (type) unknowns:" prem; ([], None))
berghofe@13607
   994
      else
berghofe@13607
   995
        let val asm = assume prem
wenzelm@15023
   996
        in (extract_safe_rrules (ss, asm), Some asm) end
berghofe@10413
   997
wenzelm@15023
   998
    and add_rrules (rrss, asms) ss =
wenzelm@15023
   999
      foldl (insert_rrule true) (ss, flat rrss) |> add_prems (mapfilter I asms)
berghofe@10413
  1000
berghofe@13607
  1001
    and disch r (prem, eq) =
berghofe@13607
  1002
      let
berghofe@13607
  1003
        val (lhs, rhs) = dest_eq eq;
berghofe@13607
  1004
        val eq' = implies_elim (Thm.instantiate
berghofe@13607
  1005
          ([], [(cA, prem), (cB, lhs), (cC, rhs)]) Drule.imp_cong)
berghofe@13607
  1006
          (implies_intr prem eq)
berghofe@13607
  1007
      in if not r then eq' else
berghofe@10413
  1008
        let
berghofe@13607
  1009
          val (prem', concl) = dest_implies lhs;
berghofe@13607
  1010
          val (prem'', _) = dest_implies rhs
berghofe@13607
  1011
        in transitive (transitive
berghofe@13607
  1012
          (Thm.instantiate ([], [(cA, prem'), (cB, prem), (cC, concl)])
berghofe@13607
  1013
             Drule.swap_prems_eq) eq')
berghofe@13607
  1014
          (Thm.instantiate ([], [(cA, prem), (cB, prem''), (cC, concl)])
berghofe@13607
  1015
             Drule.swap_prems_eq)
berghofe@10413
  1016
        end
berghofe@10413
  1017
      end
berghofe@10413
  1018
berghofe@13607
  1019
    and rebuild [] _ _ _ _ eq = eq
wenzelm@15023
  1020
      | rebuild (prem :: prems) concl (rrs :: rrss) (asm :: asms) ss eq =
berghofe@13607
  1021
          let
wenzelm@15023
  1022
            val ss' = add_rrules (rev rrss, rev asms) ss;
berghofe@13607
  1023
            val concl' =
berghofe@13607
  1024
              Drule.mk_implies (prem, if_none (apsome rhs_of eq) concl);
berghofe@13607
  1025
            val dprem = apsome (curry (disch false) prem)
wenzelm@15023
  1026
          in case rewritec (prover, sign, maxidx) ss' concl' of
wenzelm@15023
  1027
              None => rebuild prems concl' rrss asms ss (dprem eq)
berghofe@13607
  1028
            | Some (eq', _) => transitive2 (foldl (disch false o swap)
berghofe@13607
  1029
                  (the (transitive3 (dprem eq) eq'), prems))
wenzelm@15023
  1030
                (mut_impc0 (rev prems) (rhs_of eq') (rev rrss) (rev asms) ss)
berghofe@13607
  1031
          end
wenzelm@15023
  1032
wenzelm@15023
  1033
    and mut_impc0 prems concl rrss asms ss =
berghofe@13607
  1034
      let
berghofe@13607
  1035
        val prems' = strip_imp_prems concl;
wenzelm@15023
  1036
        val (rrss', asms') = split_list (map (rules_of_prem ss) prems')
berghofe@13607
  1037
      in mut_impc (prems @ prems') (strip_imp_concl concl) (rrss @ rrss')
wenzelm@15023
  1038
        (asms @ asms') [] [] [] [] ss ~1 ~1
berghofe@13607
  1039
      end
wenzelm@15023
  1040
wenzelm@15023
  1041
    and mut_impc [] concl [] [] prems' rrss' asms' eqns ss changed k =
berghofe@13607
  1042
        transitive1 (foldl (fn (eq2, (eq1, prem)) => transitive1 eq1
berghofe@13607
  1043
            (apsome (curry (disch false) prem) eq2)) (None, eqns ~~ prems'))
berghofe@13607
  1044
          (if changed > 0 then
berghofe@13607
  1045
             mut_impc (rev prems') concl (rev rrss') (rev asms')
wenzelm@15023
  1046
               [] [] [] [] ss ~1 changed
wenzelm@15023
  1047
           else rebuild prems' concl rrss' asms' ss
wenzelm@15023
  1048
             (botc skel0 (add_rrules (rev rrss', rev asms') ss) concl))
berghofe@13607
  1049
berghofe@13607
  1050
      | mut_impc (prem :: prems) concl (rrs :: rrss) (asm :: asms)
wenzelm@15023
  1051
          prems' rrss' asms' eqns ss changed k =
berghofe@13607
  1052
        case (if k = 0 then None else botc skel0 (add_rrules
wenzelm@15023
  1053
          (rev rrss' @ rrss, rev asms' @ asms) ss) prem) of
berghofe@13607
  1054
            None => mut_impc prems concl rrss asms (prem :: prems')
wenzelm@15023
  1055
              (rrs :: rrss') (asm :: asms') (None :: eqns) ss changed
berghofe@13607
  1056
              (if k = 0 then 0 else k - 1)
berghofe@13607
  1057
          | Some eqn =>
berghofe@13607
  1058
            let
berghofe@13607
  1059
              val prem' = rhs_of eqn;
berghofe@13607
  1060
              val tprems = map term_of prems;
berghofe@13607
  1061
              val i = 1 + foldl Int.max (~1, map (fn p =>
berghofe@13607
  1062
                find_index_eq p tprems) (#hyps (rep_thm eqn)));
wenzelm@15023
  1063
              val (rrs', asm') = rules_of_prem ss prem'
berghofe@13607
  1064
            in mut_impc prems concl rrss asms (prem' :: prems')
berghofe@13607
  1065
              (rrs' :: rrss') (asm' :: asms') (Some (foldr (disch true)
skalberg@15001
  1066
                (take (i, prems), Drule.imp_cong' eqn (reflexive (Drule.list_implies
wenzelm@15023
  1067
                  (drop (i, prems), concl))))) :: eqns) ss (length prems') ~1
berghofe@13607
  1068
            end
berghofe@13607
  1069
wenzelm@15023
  1070
     (*legacy code - only for backwards compatibility*)
wenzelm@15023
  1071
     and nonmut_impc ct ss =
berghofe@13607
  1072
       let val (prem, conc) = dest_implies ct;
wenzelm@15023
  1073
           val thm1 = if simprem then botc skel0 ss prem else None;
berghofe@10413
  1074
           val prem1 = if_none (apsome rhs_of thm1) prem;
wenzelm@15023
  1075
           val ss1 = if not useprem then ss else add_rrules
wenzelm@15023
  1076
             (apsnd single (apfst single (rules_of_prem ss prem1))) ss
wenzelm@15023
  1077
       in (case botc skel0 ss1 conc of
berghofe@10413
  1078
           None => (case thm1 of
berghofe@10413
  1079
               None => None
skalberg@15001
  1080
             | Some thm1' => Some (Drule.imp_cong' thm1' (reflexive conc)))
berghofe@10413
  1081
         | Some thm2 =>
berghofe@13607
  1082
           let val thm2' = disch false (prem1, thm2)
berghofe@10413
  1083
           in (case thm1 of
berghofe@10413
  1084
               None => Some thm2'
berghofe@13607
  1085
             | Some thm1' =>
skalberg@15001
  1086
                 Some (transitive (Drule.imp_cong' thm1' (reflexive conc)) thm2'))
berghofe@10413
  1087
           end)
berghofe@10413
  1088
       end
berghofe@10413
  1089
wenzelm@15023
  1090
 in try_botc end;
berghofe@10413
  1091
berghofe@10413
  1092
wenzelm@15023
  1093
(* Meta-rewriting: rewrites t to u and returns the theorem t==u *)
berghofe@10413
  1094
berghofe@10413
  1095
(*
berghofe@10413
  1096
  Parameters:
berghofe@10413
  1097
    mode = (simplify A,
berghofe@10413
  1098
            use A in simplifying B,
berghofe@10413
  1099
            use prems of B (if B is again a meta-impl.) to simplify A)
berghofe@10413
  1100
           when simplifying A ==> B
berghofe@10413
  1101
    prover: how to solve premises in conditional rewrites and congruences
berghofe@10413
  1102
*)
berghofe@10413
  1103
wenzelm@15023
  1104
fun rewrite_cterm mode prover ss ct =
wenzelm@15023
  1105
  let
wenzelm@15023
  1106
    val Simpset ({depth, ...}, _) = ss;
wenzelm@15023
  1107
    val {sign, t, maxidx, ...} = Thm.rep_cterm ct;
wenzelm@15023
  1108
  in
wenzelm@15023
  1109
    trace_cterm false "SIMPLIFIER INVOKED ON THE FOLLOWING TERM:" ct;
wenzelm@15023
  1110
    simp_depth := depth;
wenzelm@15023
  1111
    bottomc (mode, prover, sign, maxidx) ss ct
wenzelm@15023
  1112
  end handle THM (s, _, thms) =>
berghofe@10413
  1113
    error ("Exception THM was raised in simplifier:\n" ^ s ^ "\n" ^
wenzelm@11886
  1114
      Pretty.string_of (Display.pretty_thms thms));
berghofe@10413
  1115
wenzelm@11760
  1116
(*Rewrite a cterm*)
wenzelm@11767
  1117
fun rewrite_aux _ _ [] = (fn ct => Thm.reflexive ct)
wenzelm@15023
  1118
  | rewrite_aux prover full thms =
wenzelm@15023
  1119
      rewrite_cterm (full, false, false) prover (empty_ss addsimps thms);
wenzelm@11672
  1120
berghofe@10413
  1121
(*Rewrite a theorem*)
wenzelm@11767
  1122
fun simplify_aux _ _ [] = (fn th => th)
wenzelm@11767
  1123
  | simplify_aux prover full thms =
wenzelm@15023
  1124
      Drule.fconv_rule (rewrite_cterm (full, false, false) prover (empty_ss addsimps thms));
berghofe@10413
  1125
wenzelm@15023
  1126
(*simple term rewriting -- no proof*)
wenzelm@15023
  1127
fun rewrite_term sg rules procs =
wenzelm@15023
  1128
  Pattern.rewrite_term (Sign.tsig_of sg) (map decomp_simp' rules) procs;
wenzelm@15023
  1129
wenzelm@15023
  1130
fun rewrite_thm mode prover ss = Drule.fconv_rule (rewrite_cterm mode prover ss);
berghofe@10413
  1131
berghofe@10413
  1132
(*Rewrite the subgoals of a proof state (represented by a theorem) *)
berghofe@10413
  1133
fun rewrite_goals_rule_aux _ []   th = th
berghofe@10413
  1134
  | rewrite_goals_rule_aux prover thms th =
skalberg@15001
  1135
      Drule.fconv_rule (Drule.goals_conv (K true) (rewrite_cterm (true, true, false) prover
wenzelm@15023
  1136
        (empty_ss addsimps thms))) th;
berghofe@10413
  1137
wenzelm@15023
  1138
(*Rewrite the subgoal of a proof state (represented by a theorem)*)
skalberg@15011
  1139
fun rewrite_goal_rule mode prover ss i thm =
berghofe@10413
  1140
  if 0 < i  andalso  i <= nprems_of thm
skalberg@15011
  1141
  then Drule.fconv_rule (Drule.goals_conv (fn j => j=i) (rewrite_cterm mode prover ss)) thm
berghofe@10413
  1142
  else raise THM("rewrite_goal_rule",i,[thm]);
berghofe@10413
  1143
wenzelm@15023
  1144
(*Rewrite subgoal i only.  SELECT_GOAL avoids inefficiencies in goals_conv.*)
wenzelm@15023
  1145
fun asm_rewrite_goal_tac mode prover_tac ss =
wenzelm@15023
  1146
  SELECT_GOAL
wenzelm@15023
  1147
    (PRIMITIVE (rewrite_goal_rule mode (SINGLE o prover_tac) ss 1));
wenzelm@12783
  1148
wenzelm@15023
  1149
skalberg@15006
  1150
wenzelm@15023
  1151
(** simplification tactics and rules **)
skalberg@15006
  1152
wenzelm@15023
  1153
fun solve_all_tac solvers ss =
skalberg@15006
  1154
  let
wenzelm@15023
  1155
    val Simpset (_, {subgoal_tac, ...}) = ss;
wenzelm@15023
  1156
    val solve_tac = subgoal_tac (set_solvers solvers ss) THEN_ALL_NEW (K no_tac);
wenzelm@15023
  1157
  in DEPTH_SOLVE (solve_tac 1) end;
skalberg@15006
  1158
wenzelm@15023
  1159
(*NOTE: may instantiate unknowns that appear also in other subgoals*)
wenzelm@15023
  1160
fun generic_simp_tac safe mode ss =
wenzelm@15023
  1161
  let
wenzelm@15023
  1162
    val Simpset ({prems, ...}, {loop_tacs, solvers = (unsafe_solvers, solvers), ...}) = ss;
wenzelm@15023
  1163
    val loop_tac = FIRST' (map #2 loop_tacs);
wenzelm@15023
  1164
    val solve_tac = FIRST' (map (solver prems) (if safe then solvers else unsafe_solvers));
skalberg@15006
  1165
wenzelm@15023
  1166
    fun simp_loop_tac i =
wenzelm@15023
  1167
      asm_rewrite_goal_tac mode (solve_all_tac unsafe_solvers) ss i THEN
wenzelm@15023
  1168
      (solve_tac i ORELSE TRY ((loop_tac THEN_ALL_NEW simp_loop_tac) i));
wenzelm@15023
  1169
  in simp_loop_tac end;
skalberg@15006
  1170
wenzelm@15023
  1171
fun simp rew mode ss thm =
skalberg@15006
  1172
  let
wenzelm@15023
  1173
    val Simpset (_, {solvers = (unsafe_solvers, _), ...}) = ss;
wenzelm@15023
  1174
    val tacf = solve_all_tac unsafe_solvers;
wenzelm@15023
  1175
    fun prover s th = apsome #1 (Seq.pull (tacf s th));
skalberg@15011
  1176
  in rew mode prover ss thm end;
skalberg@15006
  1177
skalberg@15006
  1178
val simp_thm = simp rewrite_thm;
skalberg@15006
  1179
val simp_cterm = simp rewrite_cterm;
skalberg@15006
  1180
berghofe@10413
  1181
end;
berghofe@10413
  1182
wenzelm@11672
  1183
structure BasicMetaSimplifier: BASIC_META_SIMPLIFIER = MetaSimplifier;
wenzelm@11672
  1184
open BasicMetaSimplifier;