proposition: Lemma freshfUn h1 h2 : valid (h1 \+ h2) -> fresh h1 <= fresh (h1 \+ h2).
proof: Proof. by apply: lastkeyfUn. Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path interval) pcm(options prelude pred finmap rtc seqext useqord uslice uconsec)