∀ {α : Type u} {r : Std.Rii α} [inst : LT α] [DecidableLT α] [inst_2 : Std.PRange.Least? α]
  [inst_3 : Std.PRange.UpwardEnumerable α] [inst_4 : Std.PRange.LawfulUpwardEnumerable α]
  [Std.PRange.LawfulUpwardEnumerableLT α] [Std.PRange.LawfulUpwardEnumerableLeast? α] [inst : Std.Rxi.IsAlwaysFinite α],
  (r.toList = []) = ¬Nonempty α