proposition: Lemma dot_test a b of is_test a & is_test b : is_test (a·b).
proof: Proof. constructor. rewrite -pardot. apply: domtst. Qed.
imports: HB(structures) Coq(Setoid Morphisms) mathcomp(all_ssreflect) GraphTheory(edone preliminaries setoid_bigop structures)