helm/software/matita/nlibrary/logic/equality.ma

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  14
  15 include "logic/connectives.ma".
  16
  17 ninductive eq (A: Type) (a: A) : A → Prop ≝
  18  refl: eq A a a.
  19
  20 interpretation "leibnitz's equality" 'eq t x y = (eq t x y).
  21
  22 interpretation "leibnitz's non-equality" 'neq t x y = (Not (eq t x y)).