∀ {α : Type u} {r : Std.Rii α} [inst : Std.PRange.Least? α] [inst_1 : Std.PRange.UpwardEnumerable α]
  [inst_2 : Std.PRange.LawfulUpwardEnumerable α] [inst_3 : Std.Rxi.IsAlwaysFinite α],
  r.toList =
    match Std.PRange.least? with
    | none => []
    | some init => init...*.toList