struct Nil
  @[AlwaysInline]
  def to_b62? : String?
    nil
  end

  @[AlwaysInline]
  def to_base62? : String?
    nil
  end

  @[AlwaysInline]
  def to_i64_from_b62? : Int64?
    nil
  end

  @[AlwaysInline]
  def empty? : Bool
    true
  end

  @[AlwaysInline]
  def e : String
    ""
  end
end
