proposition: Lemma updE k v f : upd k v f = to (UM.upd k v (from f)).
proof: Proof. by case: U k v f=>x [*]. Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path bigop) pcm(options prelude finmap seqperm pred seqext) pcm(pcm morphism)