proposition: Lemma eqr_norml x y : (`|x| == y) = ((x == y) || (x == -y)) && (0 <= y).
proof: Proof. exact: real_eqr_norml. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)