fact: Definition OutOf {ts} {T : Type} (n : positive) (pf : pmap_lookup' ts n = Some T) : OneOf ts -> option T := match pf in _ = X return OneOf ts -> option match X with | None => Empty_set:Type | Some T => T end with | eq_refl => @asNth ts n end.
imports: Coq(PArith) ExtLib.Data.Map.FMapPositive ExtLib.Data.Eq ExtLib.Tactics.Injection Coq(PArith)