proposition: Lemma lookup_omap_Some {A B} (f : A → option B) (m : M A) i y : omap f m !! i = Some y ↔ ∃ x, f x = Some y ∧ m !! i = Some x.
proof: Proof. rewrite lookup_omap, bind_Some. naive_solver. Qed.
imports: Coq(Permutation) stdpp(options)