matita/contribs/RELATIONAL/Zah/defs.ma

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  14
  15 set "baseuri" "cic:/matita/RELATIONAL/Zah/defs".
  16
  17 include "datatypes/constructors.ma".
  18 include "logic/coimplication.ma".
  19 include "NPlusList/defs.ma".
  20
  21 definition Zah \def Nat \times Nat.
  22 (*
  23 definition ZEq: Zah \to Zah -> Prop :=
  24    \lambda z1,z2.
  25    \forall n. ((\fst z1) + (\snd z2) == n) \liff (\fst z2) + (\snd z1) == n.
  26
  27 interpretation "integer equality" 'zeq x y =
  28  (cic:/matita/RELATIONAL/Zah/defs/ZEq.con x y).
  29
  30 notation "hvbox(a break = b)"
  31   non associative with precedence 45
  32 for @{ 'zeq $a $b }.
  33 *)