proposition: Lemma umallbPtUn p k v f : valid (pts k v \+ f) -> um_allb p (pts k v \+ f) = p (k, v) && um_allb p f.
proof: Proof. by move=>W; rewrite umallbUn // umallbPt // (validPtUn_cond W). Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path bigop) pcm(options prelude finmap seqperm pred seqext) pcm(pcm morphism)