| 23164 |      1 | (*  Title:      HOL/nat_simprocs.ML
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|  |      2 |     ID:         $Id$
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|  |      3 |     Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
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|  |      4 |     Copyright   2000  University of Cambridge
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|  |      5 | 
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|  |      6 | Simprocs for nat numerals.
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|  |      7 | *)
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|  |      8 | 
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|  |      9 | structure Nat_Numeral_Simprocs =
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|  |     10 | struct
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|  |     11 | 
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|  |     12 | (*Maps n to #n for n = 0, 1, 2*)
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|  |     13 | val numeral_syms =
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| 23471 |     14 |        [@{thm nat_numeral_0_eq_0} RS sym, @{thm nat_numeral_1_eq_1} RS sym, @{thm numeral_2_eq_2} RS sym];
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| 23164 |     15 | val numeral_sym_ss = HOL_ss addsimps numeral_syms;
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|  |     16 | 
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|  |     17 | fun rename_numerals th =
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|  |     18 |     simplify numeral_sym_ss (Thm.transfer (the_context ()) th);
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|  |     19 | 
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|  |     20 | (*Utilities*)
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|  |     21 | 
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|  |     22 | fun mk_number n = HOLogic.number_of_const HOLogic.natT $ HOLogic.mk_numeral n;
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|  |     23 | fun dest_number t = IntInf.max (0, snd (HOLogic.dest_number t));
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|  |     24 | 
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|  |     25 | fun find_first_numeral past (t::terms) =
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|  |     26 |         ((dest_number t, t, rev past @ terms)
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|  |     27 |          handle TERM _ => find_first_numeral (t::past) terms)
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|  |     28 |   | find_first_numeral past [] = raise TERM("find_first_numeral", []);
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|  |     29 | 
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|  |     30 | val zero = mk_number 0;
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|  |     31 | val mk_plus = HOLogic.mk_binop @{const_name HOL.plus};
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|  |     32 | 
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|  |     33 | (*Thus mk_sum[t] yields t+0; longer sums don't have a trailing zero*)
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|  |     34 | fun mk_sum []        = zero
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|  |     35 |   | mk_sum [t,u]     = mk_plus (t, u)
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|  |     36 |   | mk_sum (t :: ts) = mk_plus (t, mk_sum ts);
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|  |     37 | 
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|  |     38 | (*this version ALWAYS includes a trailing zero*)
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|  |     39 | fun long_mk_sum []        = HOLogic.zero
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|  |     40 |   | long_mk_sum (t :: ts) = mk_plus (t, mk_sum ts);
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|  |     41 | 
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|  |     42 | val dest_plus = HOLogic.dest_bin @{const_name HOL.plus} HOLogic.natT;
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|  |     43 | 
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|  |     44 | 
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|  |     45 | (** Other simproc items **)
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|  |     46 | 
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|  |     47 | val trans_tac = Int_Numeral_Simprocs.trans_tac;
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|  |     48 | 
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|  |     49 | val bin_simps =
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| 23471 |     50 |      [@{thm nat_numeral_0_eq_0} RS sym, @{thm nat_numeral_1_eq_1} RS sym,
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|  |     51 |       @{thm add_nat_number_of}, @{thm nat_number_of_add_left}, 
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|  |     52 |       @{thm diff_nat_number_of}, @{thm le_number_of_eq_not_less},
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|  |     53 |       @{thm mult_nat_number_of}, @{thm nat_number_of_mult_left}, 
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|  |     54 |       @{thm less_nat_number_of}, 
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|  |     55 |       @{thm Let_number_of}, @{thm nat_number_of}] @
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| 23164 |     56 |      arith_simps @ rel_simps;
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|  |     57 | 
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|  |     58 | fun prep_simproc (name, pats, proc) =
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|  |     59 |   Simplifier.simproc (the_context ()) name pats proc;
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|  |     60 | 
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|  |     61 | 
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|  |     62 | (*** CancelNumerals simprocs ***)
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|  |     63 | 
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|  |     64 | val one = mk_number 1;
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|  |     65 | val mk_times = HOLogic.mk_binop @{const_name HOL.times};
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|  |     66 | 
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|  |     67 | fun mk_prod [] = one
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|  |     68 |   | mk_prod [t] = t
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|  |     69 |   | mk_prod (t :: ts) = if t = one then mk_prod ts
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|  |     70 |                         else mk_times (t, mk_prod ts);
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|  |     71 | 
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|  |     72 | val dest_times = HOLogic.dest_bin @{const_name HOL.times} HOLogic.natT;
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|  |     73 | 
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|  |     74 | fun dest_prod t =
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|  |     75 |       let val (t,u) = dest_times t
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|  |     76 |       in  dest_prod t @ dest_prod u  end
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|  |     77 |       handle TERM _ => [t];
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|  |     78 | 
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|  |     79 | (*DON'T do the obvious simplifications; that would create special cases*)
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|  |     80 | fun mk_coeff (k,t) = mk_times (mk_number k, t);
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|  |     81 | 
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|  |     82 | (*Express t as a product of (possibly) a numeral with other factors, sorted*)
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|  |     83 | fun dest_coeff t =
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|  |     84 |     let val ts = sort Term.term_ord (dest_prod t)
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|  |     85 |         val (n, _, ts') = find_first_numeral [] ts
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|  |     86 |                           handle TERM _ => (1, one, ts)
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|  |     87 |     in (n, mk_prod ts') end;
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|  |     88 | 
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|  |     89 | (*Find first coefficient-term THAT MATCHES u*)
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|  |     90 | fun find_first_coeff past u [] = raise TERM("find_first_coeff", [])
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|  |     91 |   | find_first_coeff past u (t::terms) =
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|  |     92 |         let val (n,u') = dest_coeff t
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|  |     93 |         in  if u aconv u' then (n, rev past @ terms)
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|  |     94 |                           else find_first_coeff (t::past) u terms
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|  |     95 |         end
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|  |     96 |         handle TERM _ => find_first_coeff (t::past) u terms;
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|  |     97 | 
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|  |     98 | 
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|  |     99 | (*Split up a sum into the list of its constituent terms, on the way removing any
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|  |    100 |   Sucs and counting them.*)
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|  |    101 | fun dest_Suc_sum (Const ("Suc", _) $ t, (k,ts)) = dest_Suc_sum (t, (k+1,ts))
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|  |    102 |   | dest_Suc_sum (t, (k,ts)) = 
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|  |    103 |       let val (t1,t2) = dest_plus t
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|  |    104 |       in  dest_Suc_sum (t1, dest_Suc_sum (t2, (k,ts)))  end
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|  |    105 |       handle TERM _ => (k, t::ts);
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|  |    106 | 
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|  |    107 | (*Code for testing whether numerals are already used in the goal*)
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|  |    108 | fun is_numeral (Const(@{const_name Numeral.number_of}, _) $ w) = true
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|  |    109 |   | is_numeral _ = false;
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|  |    110 | 
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|  |    111 | fun prod_has_numeral t = exists is_numeral (dest_prod t);
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|  |    112 | 
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|  |    113 | (*The Sucs found in the term are converted to a binary numeral. If relaxed is false,
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|  |    114 |   an exception is raised unless the original expression contains at least one
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|  |    115 |   numeral in a coefficient position.  This prevents nat_combine_numerals from 
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|  |    116 |   introducing numerals to goals.*)
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|  |    117 | fun dest_Sucs_sum relaxed t = 
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|  |    118 |   let val (k,ts) = dest_Suc_sum (t,(0,[]))
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|  |    119 |   in
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|  |    120 |      if relaxed orelse exists prod_has_numeral ts then 
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|  |    121 |        if k=0 then ts
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|  |    122 |        else mk_number (IntInf.fromInt k) :: ts
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|  |    123 |      else raise TERM("Nat_Numeral_Simprocs.dest_Sucs_sum", [t])
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|  |    124 |   end;
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|  |    125 | 
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|  |    126 | 
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|  |    127 | (*Simplify 1*n and n*1 to n*)
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|  |    128 | val add_0s  = map rename_numerals [add_0, add_0_right];
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|  |    129 | val mult_1s = map rename_numerals [@{thm nat_mult_1}, @{thm nat_mult_1_right}];
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|  |    130 | 
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|  |    131 | (*Final simplification: cancel + and *; replace Numeral0 by 0 and Numeral1 by 1*)
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|  |    132 | 
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|  |    133 | (*And these help the simproc return False when appropriate, which helps
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|  |    134 |   the arith prover.*)
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|  |    135 | val contra_rules = [add_Suc, add_Suc_right, Zero_not_Suc, Suc_not_Zero,
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|  |    136 |                     le_0_eq];
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|  |    137 | 
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|  |    138 | val simplify_meta_eq =
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|  |    139 |     Int_Numeral_Simprocs.simplify_meta_eq
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| 23471 |    140 |         ([@{thm nat_numeral_0_eq_0}, @{thm numeral_1_eq_Suc_0}, @{thm add_0}, @{thm add_0_right},
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|  |    141 |           @{thm mult_0}, @{thm mult_0_right}, @{thm mult_1}, @{thm mult_1_right}] @ contra_rules);
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| 23164 |    142 | 
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|  |    143 | 
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|  |    144 | (*Like HOL_ss but with an ordering that brings numerals to the front
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|  |    145 |   under AC-rewriting.*)
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|  |    146 | val num_ss = Int_Numeral_Simprocs.num_ss;
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|  |    147 | 
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|  |    148 | (*** Applying CancelNumeralsFun ***)
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|  |    149 | 
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|  |    150 | structure CancelNumeralsCommon =
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|  |    151 |   struct
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|  |    152 |   val mk_sum            = (fn T:typ => mk_sum)
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|  |    153 |   val dest_sum          = dest_Sucs_sum true
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|  |    154 |   val mk_coeff          = mk_coeff
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|  |    155 |   val dest_coeff        = dest_coeff
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|  |    156 |   val find_first_coeff  = find_first_coeff []
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|  |    157 |   val trans_tac         = fn _ => trans_tac
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|  |    158 | 
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|  |    159 |   val norm_ss1 = num_ss addsimps numeral_syms @ add_0s @ mult_1s @
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| 23471 |    160 |     [@{thm Suc_eq_add_numeral_1_left}] @ add_ac
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| 23164 |    161 |   val norm_ss2 = num_ss addsimps bin_simps @ add_ac @ mult_ac
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|  |    162 |   fun norm_tac ss = 
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|  |    163 |     ALLGOALS (simp_tac (Simplifier.inherit_context ss norm_ss1))
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|  |    164 |     THEN ALLGOALS (simp_tac (Simplifier.inherit_context ss norm_ss2))
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|  |    165 | 
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|  |    166 |   val numeral_simp_ss = HOL_ss addsimps add_0s @ bin_simps;
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|  |    167 |   fun numeral_simp_tac ss = ALLGOALS (simp_tac (Simplifier.inherit_context ss numeral_simp_ss));
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|  |    168 |   val simplify_meta_eq  = simplify_meta_eq
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|  |    169 |   end;
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|  |    170 | 
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|  |    171 | 
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|  |    172 | structure EqCancelNumerals = CancelNumeralsFun
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|  |    173 |  (open CancelNumeralsCommon
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|  |    174 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    175 |   val mk_bal   = HOLogic.mk_eq
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|  |    176 |   val dest_bal = HOLogic.dest_bin "op =" HOLogic.natT
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| 23471 |    177 |   val bal_add1 = @{thm nat_eq_add_iff1} RS trans
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|  |    178 |   val bal_add2 = @{thm nat_eq_add_iff2} RS trans
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| 23164 |    179 | );
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|  |    180 | 
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|  |    181 | structure LessCancelNumerals = CancelNumeralsFun
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|  |    182 |  (open CancelNumeralsCommon
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|  |    183 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    184 |   val mk_bal   = HOLogic.mk_binrel @{const_name Orderings.less}
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|  |    185 |   val dest_bal = HOLogic.dest_bin @{const_name Orderings.less} HOLogic.natT
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| 23471 |    186 |   val bal_add1 = @{thm nat_less_add_iff1} RS trans
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|  |    187 |   val bal_add2 = @{thm nat_less_add_iff2} RS trans
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| 23164 |    188 | );
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|  |    189 | 
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|  |    190 | structure LeCancelNumerals = CancelNumeralsFun
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|  |    191 |  (open CancelNumeralsCommon
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|  |    192 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    193 |   val mk_bal   = HOLogic.mk_binrel @{const_name Orderings.less_eq}
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|  |    194 |   val dest_bal = HOLogic.dest_bin @{const_name Orderings.less_eq} HOLogic.natT
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| 23471 |    195 |   val bal_add1 = @{thm nat_le_add_iff1} RS trans
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|  |    196 |   val bal_add2 = @{thm nat_le_add_iff2} RS trans
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| 23164 |    197 | );
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|  |    198 | 
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|  |    199 | structure DiffCancelNumerals = CancelNumeralsFun
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|  |    200 |  (open CancelNumeralsCommon
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|  |    201 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    202 |   val mk_bal   = HOLogic.mk_binop @{const_name HOL.minus}
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|  |    203 |   val dest_bal = HOLogic.dest_bin @{const_name HOL.minus} HOLogic.natT
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| 23471 |    204 |   val bal_add1 = @{thm nat_diff_add_eq1} RS trans
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|  |    205 |   val bal_add2 = @{thm nat_diff_add_eq2} RS trans
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| 23164 |    206 | );
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|  |    207 | 
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|  |    208 | 
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|  |    209 | val cancel_numerals =
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|  |    210 |   map prep_simproc
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|  |    211 |    [("nateq_cancel_numerals",
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|  |    212 |      ["(l::nat) + m = n", "(l::nat) = m + n",
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|  |    213 |       "(l::nat) * m = n", "(l::nat) = m * n",
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|  |    214 |       "Suc m = n", "m = Suc n"],
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|  |    215 |      K EqCancelNumerals.proc),
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|  |    216 |     ("natless_cancel_numerals",
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|  |    217 |      ["(l::nat) + m < n", "(l::nat) < m + n",
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|  |    218 |       "(l::nat) * m < n", "(l::nat) < m * n",
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|  |    219 |       "Suc m < n", "m < Suc n"],
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|  |    220 |      K LessCancelNumerals.proc),
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|  |    221 |     ("natle_cancel_numerals",
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|  |    222 |      ["(l::nat) + m <= n", "(l::nat) <= m + n",
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|  |    223 |       "(l::nat) * m <= n", "(l::nat) <= m * n",
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|  |    224 |       "Suc m <= n", "m <= Suc n"],
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|  |    225 |      K LeCancelNumerals.proc),
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|  |    226 |     ("natdiff_cancel_numerals",
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|  |    227 |      ["((l::nat) + m) - n", "(l::nat) - (m + n)",
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|  |    228 |       "(l::nat) * m - n", "(l::nat) - m * n",
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|  |    229 |       "Suc m - n", "m - Suc n"],
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|  |    230 |      K DiffCancelNumerals.proc)];
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|  |    231 | 
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|  |    232 | 
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|  |    233 | (*** Applying CombineNumeralsFun ***)
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|  |    234 | 
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|  |    235 | structure CombineNumeralsData =
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|  |    236 |   struct
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|  |    237 |   type coeff            = IntInf.int
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|  |    238 |   val iszero            = (fn x : IntInf.int => x = 0)
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|  |    239 |   val add               = IntInf.+
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|  |    240 |   val mk_sum            = (fn T:typ => long_mk_sum)  (*to work for 2*x + 3*x *)
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|  |    241 |   val dest_sum          = dest_Sucs_sum false
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|  |    242 |   val mk_coeff          = mk_coeff
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|  |    243 |   val dest_coeff        = dest_coeff
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| 23471 |    244 |   val left_distrib      = @{thm left_add_mult_distrib} RS trans
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| 23164 |    245 |   val prove_conv        = Int_Numeral_Base_Simprocs.prove_conv_nohyps
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|  |    246 |   val trans_tac         = fn _ => trans_tac
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|  |    247 | 
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| 23471 |    248 |   val norm_ss1 = num_ss addsimps numeral_syms @ add_0s @ mult_1s @ [@{thm Suc_eq_add_numeral_1}] @ add_ac
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| 23164 |    249 |   val norm_ss2 = num_ss addsimps bin_simps @ add_ac @ mult_ac
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|  |    250 |   fun norm_tac ss =
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|  |    251 |     ALLGOALS (simp_tac (Simplifier.inherit_context ss norm_ss1))
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|  |    252 |     THEN ALLGOALS (simp_tac (Simplifier.inherit_context ss norm_ss2))
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|  |    253 | 
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|  |    254 |   val numeral_simp_ss = HOL_ss addsimps add_0s @ bin_simps;
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|  |    255 |   fun numeral_simp_tac ss = ALLGOALS (simp_tac (Simplifier.inherit_context ss numeral_simp_ss))
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|  |    256 |   val simplify_meta_eq  = simplify_meta_eq
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|  |    257 |   end;
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|  |    258 | 
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|  |    259 | structure CombineNumerals = CombineNumeralsFun(CombineNumeralsData);
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|  |    260 | 
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|  |    261 | val combine_numerals =
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|  |    262 |   prep_simproc ("nat_combine_numerals", ["(i::nat) + j", "Suc (i + j)"], K CombineNumerals.proc);
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|  |    263 | 
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|  |    264 | 
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|  |    265 | (*** Applying CancelNumeralFactorFun ***)
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|  |    266 | 
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|  |    267 | structure CancelNumeralFactorCommon =
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|  |    268 |   struct
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|  |    269 |   val mk_coeff          = mk_coeff
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|  |    270 |   val dest_coeff        = dest_coeff
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|  |    271 |   val trans_tac         = fn _ => trans_tac
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|  |    272 | 
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|  |    273 |   val norm_ss1 = num_ss addsimps
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| 23471 |    274 |     numeral_syms @ add_0s @ mult_1s @ [@{thm Suc_eq_add_numeral_1_left}] @ add_ac
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| 23164 |    275 |   val norm_ss2 = num_ss addsimps bin_simps @ add_ac @ mult_ac
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|  |    276 |   fun norm_tac ss =
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|  |    277 |     ALLGOALS (simp_tac (Simplifier.inherit_context ss norm_ss1))
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|  |    278 |     THEN ALLGOALS (simp_tac (Simplifier.inherit_context ss norm_ss2))
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|  |    279 | 
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|  |    280 |   val numeral_simp_ss = HOL_ss addsimps bin_simps
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|  |    281 |   fun numeral_simp_tac ss = ALLGOALS (simp_tac (Simplifier.inherit_context ss numeral_simp_ss))
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|  |    282 |   val simplify_meta_eq  = simplify_meta_eq
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|  |    283 |   end
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|  |    284 | 
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|  |    285 | structure DivCancelNumeralFactor = CancelNumeralFactorFun
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|  |    286 |  (open CancelNumeralFactorCommon
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|  |    287 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    288 |   val mk_bal   = HOLogic.mk_binop @{const_name Divides.div}
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|  |    289 |   val dest_bal = HOLogic.dest_bin @{const_name Divides.div} HOLogic.natT
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| 23471 |    290 |   val cancel = @{thm nat_mult_div_cancel1} RS trans
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| 23164 |    291 |   val neg_exchanges = false
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|  |    292 | )
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|  |    293 | 
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|  |    294 | structure EqCancelNumeralFactor = CancelNumeralFactorFun
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|  |    295 |  (open CancelNumeralFactorCommon
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|  |    296 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    297 |   val mk_bal   = HOLogic.mk_eq
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|  |    298 |   val dest_bal = HOLogic.dest_bin "op =" HOLogic.natT
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| 23471 |    299 |   val cancel = @{thm nat_mult_eq_cancel1} RS trans
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| 23164 |    300 |   val neg_exchanges = false
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|  |    301 | )
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|  |    302 | 
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|  |    303 | structure LessCancelNumeralFactor = CancelNumeralFactorFun
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|  |    304 |  (open CancelNumeralFactorCommon
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|  |    305 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    306 |   val mk_bal   = HOLogic.mk_binrel @{const_name Orderings.less}
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|  |    307 |   val dest_bal = HOLogic.dest_bin @{const_name Orderings.less} HOLogic.natT
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| 23471 |    308 |   val cancel = @{thm nat_mult_less_cancel1} RS trans
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| 23164 |    309 |   val neg_exchanges = true
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|  |    310 | )
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|  |    311 | 
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|  |    312 | structure LeCancelNumeralFactor = CancelNumeralFactorFun
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|  |    313 |  (open CancelNumeralFactorCommon
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|  |    314 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    315 |   val mk_bal   = HOLogic.mk_binrel @{const_name Orderings.less_eq}
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|  |    316 |   val dest_bal = HOLogic.dest_bin @{const_name Orderings.less_eq} HOLogic.natT
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| 23471 |    317 |   val cancel = @{thm nat_mult_le_cancel1} RS trans
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| 23164 |    318 |   val neg_exchanges = true
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|  |    319 | )
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|  |    320 | 
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|  |    321 | val cancel_numeral_factors =
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|  |    322 |   map prep_simproc
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|  |    323 |    [("nateq_cancel_numeral_factors",
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|  |    324 |      ["(l::nat) * m = n", "(l::nat) = m * n"],
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|  |    325 |      K EqCancelNumeralFactor.proc),
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|  |    326 |     ("natless_cancel_numeral_factors",
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|  |    327 |      ["(l::nat) * m < n", "(l::nat) < m * n"],
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|  |    328 |      K LessCancelNumeralFactor.proc),
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|  |    329 |     ("natle_cancel_numeral_factors",
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|  |    330 |      ["(l::nat) * m <= n", "(l::nat) <= m * n"],
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|  |    331 |      K LeCancelNumeralFactor.proc),
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|  |    332 |     ("natdiv_cancel_numeral_factors",
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|  |    333 |      ["((l::nat) * m) div n", "(l::nat) div (m * n)"],
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|  |    334 |      K DivCancelNumeralFactor.proc)];
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|  |    335 | 
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|  |    336 | 
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|  |    337 | 
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|  |    338 | (*** Applying ExtractCommonTermFun ***)
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|  |    339 | 
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|  |    340 | (*this version ALWAYS includes a trailing one*)
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|  |    341 | fun long_mk_prod []        = one
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|  |    342 |   | long_mk_prod (t :: ts) = mk_times (t, mk_prod ts);
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|  |    343 | 
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|  |    344 | (*Find first term that matches u*)
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|  |    345 | fun find_first_t past u []         = raise TERM("find_first_t", [])
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|  |    346 |   | find_first_t past u (t::terms) =
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|  |    347 |         if u aconv t then (rev past @ terms)
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|  |    348 |         else find_first_t (t::past) u terms
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|  |    349 |         handle TERM _ => find_first_t (t::past) u terms;
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|  |    350 | 
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|  |    351 | (** Final simplification for the CancelFactor simprocs **)
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|  |    352 | val simplify_one = Int_Numeral_Simprocs.simplify_meta_eq  
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|  |    353 |   [@{thm mult_1_left}, @{thm mult_1_right}, @{thm div_1}, @{thm numeral_1_eq_Suc_0}];
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|  |    354 | 
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|  |    355 | fun cancel_simplify_meta_eq cancel_th ss th =
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|  |    356 |     simplify_one ss (([th, cancel_th]) MRS trans);
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|  |    357 | 
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|  |    358 | structure CancelFactorCommon =
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|  |    359 |   struct
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|  |    360 |   val mk_sum            = (fn T:typ => long_mk_prod)
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|  |    361 |   val dest_sum          = dest_prod
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|  |    362 |   val mk_coeff          = mk_coeff
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|  |    363 |   val dest_coeff        = dest_coeff
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|  |    364 |   val find_first        = find_first_t []
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|  |    365 |   val trans_tac         = fn _ => trans_tac
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|  |    366 |   val norm_ss = HOL_ss addsimps mult_1s @ mult_ac
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|  |    367 |   fun norm_tac ss = ALLGOALS (simp_tac (Simplifier.inherit_context ss norm_ss))
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|  |    368 |   end;
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|  |    369 | 
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|  |    370 | structure EqCancelFactor = ExtractCommonTermFun
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|  |    371 |  (open CancelFactorCommon
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|  |    372 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    373 |   val mk_bal   = HOLogic.mk_eq
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|  |    374 |   val dest_bal = HOLogic.dest_bin "op =" HOLogic.natT
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| 23471 |    375 |   val simplify_meta_eq  = cancel_simplify_meta_eq @{thm nat_mult_eq_cancel_disj}
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| 23164 |    376 | );
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|  |    377 | 
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|  |    378 | structure LessCancelFactor = ExtractCommonTermFun
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|  |    379 |  (open CancelFactorCommon
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|  |    380 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    381 |   val mk_bal   = HOLogic.mk_binrel @{const_name Orderings.less}
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|  |    382 |   val dest_bal = HOLogic.dest_bin @{const_name Orderings.less} HOLogic.natT
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| 23471 |    383 |   val simplify_meta_eq  = cancel_simplify_meta_eq @{thm nat_mult_less_cancel_disj}
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| 23164 |    384 | );
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|  |    385 | 
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|  |    386 | structure LeCancelFactor = ExtractCommonTermFun
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|  |    387 |  (open CancelFactorCommon
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|  |    388 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    389 |   val mk_bal   = HOLogic.mk_binrel @{const_name Orderings.less_eq}
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|  |    390 |   val dest_bal = HOLogic.dest_bin @{const_name Orderings.less_eq} HOLogic.natT
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| 23471 |    391 |   val simplify_meta_eq  = cancel_simplify_meta_eq @{thm nat_mult_le_cancel_disj}
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| 23164 |    392 | );
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|  |    393 | 
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|  |    394 | structure DivideCancelFactor = ExtractCommonTermFun
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|  |    395 |  (open CancelFactorCommon
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|  |    396 |   val prove_conv = Int_Numeral_Base_Simprocs.prove_conv
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|  |    397 |   val mk_bal   = HOLogic.mk_binop @{const_name Divides.div}
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|  |    398 |   val dest_bal = HOLogic.dest_bin @{const_name Divides.div} HOLogic.natT
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| 23471 |    399 |   val simplify_meta_eq  = cancel_simplify_meta_eq @{thm nat_mult_div_cancel_disj}
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| 23164 |    400 | );
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|  |    401 | 
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|  |    402 | val cancel_factor =
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|  |    403 |   map prep_simproc
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|  |    404 |    [("nat_eq_cancel_factor",
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|  |    405 |      ["(l::nat) * m = n", "(l::nat) = m * n"],
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|  |    406 |      K EqCancelFactor.proc),
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|  |    407 |     ("nat_less_cancel_factor",
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|  |    408 |      ["(l::nat) * m < n", "(l::nat) < m * n"],
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|  |    409 |      K LessCancelFactor.proc),
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|  |    410 |     ("nat_le_cancel_factor",
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|  |    411 |      ["(l::nat) * m <= n", "(l::nat) <= m * n"],
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|  |    412 |      K LeCancelFactor.proc),
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|  |    413 |     ("nat_divide_cancel_factor",
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|  |    414 |      ["((l::nat) * m) div n", "(l::nat) div (m * n)"],
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|  |    415 |      K DivideCancelFactor.proc)];
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|  |    416 | 
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|  |    417 | end;
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|  |    418 | 
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|  |    419 | 
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|  |    420 | Addsimprocs Nat_Numeral_Simprocs.cancel_numerals;
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|  |    421 | Addsimprocs [Nat_Numeral_Simprocs.combine_numerals];
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|  |    422 | Addsimprocs Nat_Numeral_Simprocs.cancel_numeral_factors;
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|  |    423 | Addsimprocs Nat_Numeral_Simprocs.cancel_factor;
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|  |    424 | 
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|  |    425 | 
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|  |    426 | (*examples:
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|  |    427 | print_depth 22;
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|  |    428 | set timing;
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|  |    429 | set trace_simp;
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|  |    430 | fun test s = (Goal s; by (Simp_tac 1));
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|  |    431 | 
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|  |    432 | (*cancel_numerals*)
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|  |    433 | test "l +( 2) + (2) + 2 + (l + 2) + (oo  + 2) = (uu::nat)";
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|  |    434 | test "(2*length xs < 2*length xs + j)";
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|  |    435 | test "(2*length xs < length xs * 2 + j)";
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|  |    436 | test "2*u = (u::nat)";
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|  |    437 | test "2*u = Suc (u)";
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|  |    438 | test "(i + j + 12 + (k::nat)) - 15 = y";
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|  |    439 | test "(i + j + 12 + (k::nat)) - 5 = y";
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|  |    440 | test "Suc u - 2 = y";
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|  |    441 | test "Suc (Suc (Suc u)) - 2 = y";
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|  |    442 | test "(i + j + 2 + (k::nat)) - 1 = y";
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|  |    443 | test "(i + j + 1 + (k::nat)) - 2 = y";
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|  |    444 | 
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|  |    445 | test "(2*x + (u*v) + y) - v*3*u = (w::nat)";
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|  |    446 | test "(2*x*u*v + 5 + (u*v)*4 + y) - v*u*4 = (w::nat)";
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|  |    447 | test "(2*x*u*v + (u*v)*4 + y) - v*u = (w::nat)";
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|  |    448 | test "Suc (Suc (2*x*u*v + u*4 + y)) - u = w";
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|  |    449 | test "Suc ((u*v)*4) - v*3*u = w";
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|  |    450 | test "Suc (Suc ((u*v)*3)) - v*3*u = w";
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|  |    451 | 
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|  |    452 | test "(i + j + 12 + (k::nat)) = u + 15 + y";
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|  |    453 | test "(i + j + 32 + (k::nat)) - (u + 15 + y) = zz";
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|  |    454 | test "(i + j + 12 + (k::nat)) = u + 5 + y";
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|  |    455 | (*Suc*)
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|  |    456 | test "(i + j + 12 + k) = Suc (u + y)";
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|  |    457 | test "Suc (Suc (Suc (Suc (Suc (u + y))))) <= ((i + j) + 41 + k)";
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|  |    458 | test "(i + j + 5 + k) < Suc (Suc (Suc (Suc (Suc (u + y)))))";
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|  |    459 | test "Suc (Suc (Suc (Suc (Suc (u + y))))) - 5 = v";
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|  |    460 | test "(i + j + 5 + k) = Suc (Suc (Suc (Suc (Suc (Suc (Suc (u + y)))))))";
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|  |    461 | test "2*y + 3*z + 2*u = Suc (u)";
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|  |    462 | test "2*y + 3*z + 6*w + 2*y + 3*z + 2*u = Suc (u)";
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|  |    463 | test "2*y + 3*z + 6*w + 2*y + 3*z + 2*u = 2*y' + 3*z' + 6*w' + 2*y' + 3*z' + u + (vv::nat)";
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|  |    464 | test "6 + 2*y + 3*z + 4*u = Suc (vv + 2*u + z)";
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|  |    465 | test "(2*n*m) < (3*(m*n)) + (u::nat)";
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|  |    466 | 
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|  |    467 | test "(Suc (Suc (Suc (Suc (Suc (Suc (case length (f c) of 0 => 0 | Suc k => k)))))) <= Suc 0)";
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|  |    468 |  
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|  |    469 | test "Suc (Suc (Suc (Suc (Suc (Suc (length l1 + length l2)))))) <= length l1";
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|  |    470 | 
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|  |    471 | test "( (Suc (Suc (Suc (Suc (Suc (length (compT P E A ST mxr e) + length l3)))))) <= length (compT P E A ST mxr e))";
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|  |    472 | 
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|  |    473 | test "( (Suc (Suc (Suc (Suc (Suc (length (compT P E A ST mxr e) + length (compT P E (A Un \<A> e) ST mxr c))))))) <= length (compT P E A ST mxr e))";
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|  |    474 | 
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|  |    475 | 
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|  |    476 | (*negative numerals: FAIL*)
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|  |    477 | test "(i + j + -23 + (k::nat)) < u + 15 + y";
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|  |    478 | test "(i + j + 3 + (k::nat)) < u + -15 + y";
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|  |    479 | test "(i + j + -12 + (k::nat)) - 15 = y";
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|  |    480 | test "(i + j + 12 + (k::nat)) - -15 = y";
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|  |    481 | test "(i + j + -12 + (k::nat)) - -15 = y";
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|  |    482 | 
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|  |    483 | (*combine_numerals*)
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|  |    484 | test "k + 3*k = (u::nat)";
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|  |    485 | test "Suc (i + 3) = u";
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|  |    486 | test "Suc (i + j + 3 + k) = u";
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|  |    487 | test "k + j + 3*k + j = (u::nat)";
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|  |    488 | test "Suc (j*i + i + k + 5 + 3*k + i*j*4) = (u::nat)";
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|  |    489 | test "(2*n*m) + (3*(m*n)) = (u::nat)";
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|  |    490 | (*negative numerals: FAIL*)
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|  |    491 | test "Suc (i + j + -3 + k) = u";
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|  |    492 | 
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|  |    493 | (*cancel_numeral_factors*)
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|  |    494 | test "9*x = 12 * (y::nat)";
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|  |    495 | test "(9*x) div (12 * (y::nat)) = z";
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|  |    496 | test "9*x < 12 * (y::nat)";
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|  |    497 | test "9*x <= 12 * (y::nat)";
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|  |    498 | 
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|  |    499 | (*cancel_factor*)
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|  |    500 | test "x*k = k*(y::nat)";
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|  |    501 | test "k = k*(y::nat)";
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|  |    502 | test "a*(b*c) = (b::nat)";
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|  |    503 | test "a*(b*c) = d*(b::nat)*(x*a)";
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|  |    504 | 
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|  |    505 | test "x*k < k*(y::nat)";
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|  |    506 | test "k < k*(y::nat)";
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|  |    507 | test "a*(b*c) < (b::nat)";
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|  |    508 | test "a*(b*c) < d*(b::nat)*(x*a)";
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|  |    509 | 
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|  |    510 | test "x*k <= k*(y::nat)";
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|  |    511 | test "k <= k*(y::nat)";
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|  |    512 | test "a*(b*c) <= (b::nat)";
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|  |    513 | test "a*(b*c) <= d*(b::nat)*(x*a)";
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|  |    514 | 
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|  |    515 | test "(x*k) div (k*(y::nat)) = (uu::nat)";
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|  |    516 | test "(k) div (k*(y::nat)) = (uu::nat)";
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|  |    517 | test "(a*(b*c)) div ((b::nat)) = (uu::nat)";
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|  |    518 | test "(a*(b*c)) div (d*(b::nat)*(x*a)) = (uu::nat)";
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|  |    519 | *)
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|  |    520 | 
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|  |    521 | 
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|  |    522 | (*** Prepare linear arithmetic for nat numerals ***)
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|  |    523 | 
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|  |    524 | local
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|  |    525 | 
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|  |    526 | (* reduce contradictory <= to False *)
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|  |    527 | val add_rules =
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| 23471 |    528 |   [@{thm Let_number_of}, @{thm Let_0}, @{thm Let_1}, @{thm nat_0}, @{thm nat_1},
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|  |    529 |    @{thm add_nat_number_of}, @{thm diff_nat_number_of}, @{thm mult_nat_number_of},
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|  |    530 |    @{thm eq_nat_number_of}, @{thm less_nat_number_of}, @{thm le_number_of_eq_not_less},
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|  |    531 |    @{thm le_Suc_number_of}, @{thm le_number_of_Suc},
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|  |    532 |    @{thm less_Suc_number_of}, @{thm less_number_of_Suc},
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|  |    533 |    @{thm Suc_eq_number_of}, @{thm eq_number_of_Suc},
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|  |    534 |    @{thm mult_Suc}, @{thm mult_Suc_right},
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|  |    535 |    @{thm eq_number_of_0}, @{thm eq_0_number_of}, @{thm less_0_number_of},
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|  |    536 |    @{thm of_int_number_of_eq}, @{thm of_nat_number_of_eq}, @{thm nat_number_of}, @{thm if_True}, @{thm if_False}];
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| 23164 |    537 | 
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|  |    538 | val simprocs = Nat_Numeral_Simprocs.combine_numerals
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|  |    539 |   :: Nat_Numeral_Simprocs.cancel_numerals;
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|  |    540 | 
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|  |    541 | in
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|  |    542 | 
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|  |    543 | val nat_simprocs_setup =
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|  |    544 |   Fast_Arith.map_data (fn {add_mono_thms, mult_mono_thms, inj_thms, lessD, neqE, simpset} =>
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|  |    545 |    {add_mono_thms = add_mono_thms, mult_mono_thms = mult_mono_thms,
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|  |    546 |     inj_thms = inj_thms, lessD = lessD, neqE = neqE,
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|  |    547 |     simpset = simpset addsimps add_rules
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|  |    548 |                       addsimprocs simprocs});
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|  |    549 | 
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|  |    550 | end;
 |