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(************************************************************************)
(*  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        *)
(************************************************************************)

(*i $Id: Description.v 10170 2007-10-03 14:41:25Z herbelin $ i*)

(** This file provides a constructive form of definite description; it
    allows to build functions from the proof of their existence in any
    context; this is weaker than Church's iota operator *)

Require Import ChoiceFacts.

Set Implicit Arguments.

Axiom constructive_definite_description :
  forall (A : Type) (P : A->Prop), 
    (exists! x, P x) -> { x : A | P x }.