(************************************************************************)
(*  v      *   The Coq Proof Assistant  /  The Coq Development Team     *)
(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *)
(*   \VV/  **************************************************************)
(*    //   *      This file is distributed under the terms of the       *)
(*         *       GNU Lesser General Public License Version 2.1        *)
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(*i 	$Id$	 i*)
Section MapCard.
Variables A B : Type.

Lemma MapCard_is_one_unique :
forall m:Map A,
MapCard A m = 1 ->
forall (a a':ad) (y y':A),
MapGet A m a = Some y ->
MapGet A m a' = Some y' -> a = a' /\ y = y'.