proposition: Lemma subheapUnr h1 h2 : def (h1 :+ h2) -> subheap h2 (h1 :+ h2).
proof: Proof. by rewrite unC; apply: subheapUnl. Qed.
imports: mathcomp(ssreflect ssrfun ssrnat div ssrbool seq) LemmaOverloading(prelude finmap ordtype) mathcomp(path eqtype) Eqdep