proposition: Lemma domUnPtE k v f : k \in dom (f \+ pts k v) = valid (f \+ pts k v).
proof: Proof. by rewrite joinC; apply: domPtUnE. Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path bigop) pcm(options prelude finmap seqperm pred seqext) pcm(pcm morphism)