Преобразование шестнадцатеричного, десятичного, восьмеричного и ASCII?

Попытка перейти к базам и обратно в Ruby ... код, который я изложил, кажется довольно повторяющимся. Есть ли способ лучше?

module Converter
  def self.convert(value, from, to)
    case from
    when :hex
      case to
      when :dec
        # code to change hex to dec
      when :oct
        # code to change hex to oct
      when :bin
        # code to change hex to bin
      when :ascii
        # code to change hex to ascii
      end
    when :dec
      case to
      when :hex
        # code to change dec to hex
      when :oct
        # code to change dec to oct
      when :bin
        # code to change dec to bin
      when :ascii
        # code to change dec to ascii
      end
    when :oct
      case to
      when :hex
        # code to change oct to hex
      when :dec
        # code to change oct to dec
      when :bin
        # code to change oct to bin
      when :ascii
        # code to change oct to ascii
      end
    when :bin
      case to
      when :hex
        # code to change bin to hex
      when :dec
        # code to change bin to dec
      when :oct
        # code to change bin to oct
      when :ascii
        # code to change bin to ascii
      end
    when :ascii
      case to
      when :hex
        # code to change ascii to hex
      when :dec
        # code to change ascii to dec
      when :oct
        # code to change ascii to oct
      when :bin
        # code to change ascii to bin
      end
    end
  end
end