proposition: Lemma partitionE r k (f : partition k r) : untag f = k \+ r.
proof: Proof. by case: f=>[[j]] /=; rewrite /partition_axiom /= => ->. Qed.
imports: Coq(ssreflect ssrbool ssrfun Eqdep) mathcomp(ssrnat eqtype seq path) pcm(options axioms finmap) pcm(pcm unionmap)