proposition: Lemma reduce_shuffle v a c d of is_test a & is_test c & is_test d : c·(d·a)·(1∥v) ≡ a ∥ c·v·d.
proof: Proof. rewrite -!dotA -tstpar_r; apply: dot_eqv => //. by rewrite -partst tstpar dotx1 dotC. Qed.
imports: HB(structures) Coq(Setoid Morphisms) mathcomp(all_ssreflect) GraphTheory(edone preliminaries setoid_bigop structures)