matita/contribs/RELATIONAL/ZEq/defs.ma

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  14
  15
  16
  17 include "datatypes/Zah.ma".
  18 include "NPlus/defs.ma".
  19
  20 inductive ZEq: Zah \to Zah \to Prop :=
  21    | zeq: \forall m1,m2,m3,m4,n.
  22           (m1 + m4 == n) \to (m3 + m2 == n) \to
  23           ZEq \langle m1, m2 \rangle \langle m3, m4 \rangle
  24 .
  25
  26 interpretation "integer equality" 'eq x y =
  27  (cic:/matita/RELATIONAL/ZEq/defs/ZEq.ind#xpointer(1/1) x y).
  28