proposition: Lemma umcompf0 g : um_comp g Unit = Unit.
proof: Proof. by rewrite /um_comp umfoldl0. Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path bigop) pcm(options prelude finmap seqperm pred seqext) pcm(pcm morphism)