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(*         *      The Rocq Prover / The Rocq Development Team           *)
(*  v      *         Copyright INRIA, CNRS and contributors             *)
(* <O___,, * (see version control and CREDITS file for authors & dates) *)
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(*         *     GNU Lesser General Public License Version 2.1          *)
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(** * An absolute value for normalized rational numbers. *)
(** Contributed by Cédric Auger *)

Lemma Qcabs_null x : [x] = 0 -> x = 0.