∀ {α : Type u_1} [inst : Std.PRange.UpwardEnumerable α] [inst_1 : Std.PRange.Least? α]
  [Std.PRange.LawfulUpwardEnumerable α] [Std.PRange.LawfulUpwardEnumerableLeast? α] (r : Std.Rii α),
  ∀ a ∈ Std.Rii.Internal.iter r, a ∈ r