lean2/library/data/countable.lean

14 lines
323 B
Text
Raw Normal View History

/-
Copyright (c) 2015 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Module: data.countable
Author: Leonardo de Moura
Define countable types
-/
import algebra.function
open function
definition countable (A : Type) : Prop := ∃ f : A → nat, injective f