proposition: Lemma cancel (h1 h2 : heap) (D : def h1) (H : h1 = h2) (c : @heapeq h1 h2 empty (cancel1 D H) (cancel2 H)) : tt = dummy c -> prop c.
proof: Proof. move=>_. apply c. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool ssrnat seq eqtype) LemmaOverloading(prelude prefix heaps terms)