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(* v * The Coq Proof Assistant / The Coq Development Team *)
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(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *)
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(* \VV/ **************************************************************)
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(* // * This file is distributed under the terms of the *)
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(* * GNU Lesser General Public License Version 2.1 *)
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(*i $Id: Description.v 10170 2007-10-03 14:41:25Z herbelin $ i*)
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(** This file provides a constructive form of definite description; it
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allows to build functions from the proof of their existence in any
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context; this is weaker than Church's iota operator *)
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Require Import ChoiceFacts.
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Set Implicit Arguments.
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Axiom constructive_definite_description :
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forall (A : Type) (P : A->Prop),
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(exists! x, P x) -> { x : A | P x }.