--- a/src/HOL/Tools/numeral_simprocs.ML Fri May 07 10:00:24 2010 +0200
+++ b/src/HOL/Tools/numeral_simprocs.ML Fri May 07 15:05:52 2010 +0200
@@ -1,7 +1,7 @@
(* Author: Lawrence C Paulson, Cambridge University Computer Laboratory
Copyright 2000 University of Cambridge
-Simprocs for the integer numerals.
+Simprocs for the (integer) numerals.
*)
(*To quote from Provers/Arith/cancel_numeral_factor.ML:
@@ -24,6 +24,7 @@
val field_combine_numerals: simproc
val field_cancel_numeral_factors: simproc list
val num_ss: simpset
+ val field_comp_conv: conv
end;
structure Numeral_Simprocs : NUMERAL_SIMPROCS =
@@ -602,6 +603,157 @@
"(l::'a::field_inverse_zero) / (m * n)"],
K DivideCancelFactor.proc)];
+local
+ val zr = @{cpat "0"}
+ val zT = ctyp_of_term zr
+ val geq = @{cpat "op ="}
+ val eqT = Thm.dest_ctyp (ctyp_of_term geq) |> hd
+ val add_frac_eq = mk_meta_eq @{thm "add_frac_eq"}
+ val add_frac_num = mk_meta_eq @{thm "add_frac_num"}
+ val add_num_frac = mk_meta_eq @{thm "add_num_frac"}
+
+ fun prove_nz ss T t =
+ let
+ val z = instantiate_cterm ([(zT,T)],[]) zr
+ val eq = instantiate_cterm ([(eqT,T)],[]) geq
+ val th = Simplifier.rewrite (ss addsimps @{thms simp_thms})
+ (Thm.capply @{cterm "Trueprop"} (Thm.capply @{cterm "Not"}
+ (Thm.capply (Thm.capply eq t) z)))
+ in equal_elim (symmetric th) TrueI
+ end
+
+ fun proc phi ss ct =
+ let
+ val ((x,y),(w,z)) =
+ (Thm.dest_binop #> (fn (a,b) => (Thm.dest_binop a, Thm.dest_binop b))) ct
+ val _ = map (HOLogic.dest_number o term_of) [x,y,z,w]
+ val T = ctyp_of_term x
+ val [y_nz, z_nz] = map (prove_nz ss T) [y, z]
+ val th = instantiate' [SOME T] (map SOME [y,z,x,w]) add_frac_eq
+ in SOME (implies_elim (implies_elim th y_nz) z_nz)
+ end
+ handle CTERM _ => NONE | TERM _ => NONE | THM _ => NONE
+
+ fun proc2 phi ss ct =
+ let
+ val (l,r) = Thm.dest_binop ct
+ val T = ctyp_of_term l
+ in (case (term_of l, term_of r) of
+ (Const(@{const_name Rings.divide},_)$_$_, _) =>
+ let val (x,y) = Thm.dest_binop l val z = r
+ val _ = map (HOLogic.dest_number o term_of) [x,y,z]
+ val ynz = prove_nz ss T y
+ in SOME (implies_elim (instantiate' [SOME T] (map SOME [y,x,z]) add_frac_num) ynz)
+ end
+ | (_, Const (@{const_name Rings.divide},_)$_$_) =>
+ let val (x,y) = Thm.dest_binop r val z = l
+ val _ = map (HOLogic.dest_number o term_of) [x,y,z]
+ val ynz = prove_nz ss T y
+ in SOME (implies_elim (instantiate' [SOME T] (map SOME [y,z,x]) add_num_frac) ynz)
+ end
+ | _ => NONE)
+ end
+ handle CTERM _ => NONE | TERM _ => NONE | THM _ => NONE
+
+ fun is_number (Const(@{const_name Rings.divide},_)$a$b) = is_number a andalso is_number b
+ | is_number t = can HOLogic.dest_number t
+
+ val is_number = is_number o term_of
+
+ fun proc3 phi ss ct =
+ (case term_of ct of
+ Const(@{const_name Orderings.less},_)$(Const(@{const_name Rings.divide},_)$_$_)$_ =>
+ let
+ val ((a,b),c) = Thm.dest_binop ct |>> Thm.dest_binop
+ val _ = map is_number [a,b,c]
+ val T = ctyp_of_term c
+ val th = instantiate' [SOME T] (map SOME [a,b,c]) @{thm "divide_less_eq"}
+ in SOME (mk_meta_eq th) end
+ | Const(@{const_name Orderings.less_eq},_)$(Const(@{const_name Rings.divide},_)$_$_)$_ =>
+ let
+ val ((a,b),c) = Thm.dest_binop ct |>> Thm.dest_binop
+ val _ = map is_number [a,b,c]
+ val T = ctyp_of_term c
+ val th = instantiate' [SOME T] (map SOME [a,b,c]) @{thm "divide_le_eq"}
+ in SOME (mk_meta_eq th) end
+ | Const("op =",_)$(Const(@{const_name Rings.divide},_)$_$_)$_ =>
+ let
+ val ((a,b),c) = Thm.dest_binop ct |>> Thm.dest_binop
+ val _ = map is_number [a,b,c]
+ val T = ctyp_of_term c
+ val th = instantiate' [SOME T] (map SOME [a,b,c]) @{thm "divide_eq_eq"}
+ in SOME (mk_meta_eq th) end
+ | Const(@{const_name Orderings.less},_)$_$(Const(@{const_name Rings.divide},_)$_$_) =>
+ let
+ val (a,(b,c)) = Thm.dest_binop ct ||> Thm.dest_binop
+ val _ = map is_number [a,b,c]
+ val T = ctyp_of_term c
+ val th = instantiate' [SOME T] (map SOME [a,b,c]) @{thm "less_divide_eq"}
+ in SOME (mk_meta_eq th) end
+ | Const(@{const_name Orderings.less_eq},_)$_$(Const(@{const_name Rings.divide},_)$_$_) =>
+ let
+ val (a,(b,c)) = Thm.dest_binop ct ||> Thm.dest_binop
+ val _ = map is_number [a,b,c]
+ val T = ctyp_of_term c
+ val th = instantiate' [SOME T] (map SOME [a,b,c]) @{thm "le_divide_eq"}
+ in SOME (mk_meta_eq th) end
+ | Const("op =",_)$_$(Const(@{const_name Rings.divide},_)$_$_) =>
+ let
+ val (a,(b,c)) = Thm.dest_binop ct ||> Thm.dest_binop
+ val _ = map is_number [a,b,c]
+ val T = ctyp_of_term c
+ val th = instantiate' [SOME T] (map SOME [a,b,c]) @{thm "eq_divide_eq"}
+ in SOME (mk_meta_eq th) end
+ | _ => NONE)
+ handle TERM _ => NONE | CTERM _ => NONE | THM _ => NONE
+
+val add_frac_frac_simproc =
+ make_simproc {lhss = [@{cpat "(?x::?'a::field)/?y + (?w::?'a::field)/?z"}],
+ name = "add_frac_frac_simproc",
+ proc = proc, identifier = []}
+
+val add_frac_num_simproc =
+ make_simproc {lhss = [@{cpat "(?x::?'a::field)/?y + ?z"}, @{cpat "?z + (?x::?'a::field)/?y"}],
+ name = "add_frac_num_simproc",
+ proc = proc2, identifier = []}
+
+val ord_frac_simproc =
+ make_simproc
+ {lhss = [@{cpat "(?a::(?'a::{field, ord}))/?b < ?c"},
+ @{cpat "(?a::(?'a::{field, ord}))/?b <= ?c"},
+ @{cpat "?c < (?a::(?'a::{field, ord}))/?b"},
+ @{cpat "?c <= (?a::(?'a::{field, ord}))/?b"},
+ @{cpat "?c = ((?a::(?'a::{field, ord}))/?b)"},
+ @{cpat "((?a::(?'a::{field, ord}))/ ?b) = ?c"}],
+ name = "ord_frac_simproc", proc = proc3, identifier = []}
+
+val ths = [@{thm "mult_numeral_1"}, @{thm "mult_numeral_1_right"},
+ @{thm "divide_Numeral1"},
+ @{thm "divide_zero"}, @{thm "divide_Numeral0"},
+ @{thm "divide_divide_eq_left"},
+ @{thm "times_divide_eq_left"}, @{thm "times_divide_eq_right"},
+ @{thm "times_divide_times_eq"},
+ @{thm "divide_divide_eq_right"},
+ @{thm "diff_def"}, @{thm "minus_divide_left"},
+ @{thm "Numeral1_eq1_nat"}, @{thm "add_divide_distrib"} RS sym,
+ @{thm field_divide_inverse} RS sym, @{thm inverse_divide},
+ Conv.fconv_rule (Conv.arg_conv (Conv.arg1_conv (Conv.rewr_conv (mk_meta_eq @{thm mult_commute}))))
+ (@{thm field_divide_inverse} RS sym)]
+
+in
+
+val field_comp_conv = (Simplifier.rewrite
+(HOL_basic_ss addsimps @{thms "semiring_norm"}
+ addsimps ths addsimps @{thms simp_thms}
+ addsimprocs field_cancel_numeral_factors
+ addsimprocs [add_frac_frac_simproc, add_frac_num_simproc,
+ ord_frac_simproc]
+ addcongs [@{thm "if_weak_cong"}]))
+then_conv (Simplifier.rewrite (HOL_basic_ss addsimps
+ [@{thm numeral_1_eq_1},@{thm numeral_0_eq_0}] @ @{thms numerals(1-2)}))
+
+end
+
end;
Addsimprocs Numeral_Simprocs.cancel_numerals;