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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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(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
(*         *     (see LICENSE file for the text of the license)         *)
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Require Export Cring.
(* Definition of integral domains: commutative ring without zero divisor *)
Class Integral_domain {R : Type}`{Rcr:Cring R} := {
integral_domain_product:
forall x y, x * y == 0 -> x == 0 \/ y == 0;
integral_domain_one_zero: not (1 == 0)}.
Section integral_domain.
Context {R:Type}`{Rid:Integral_domain R}.

Lemma integral_domain_minus_one_zero: ~ - (1:R) == 0.
red;intro. apply integral_domain_one_zero.