proposition: Lemma daddeA_subproof : associative (S := \bar^d R) dual_adde.
proof: Proof. by case=> [x||] [y||] [z||] //; rewrite /dual_adde /= addrA. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra) signed