delegate.rb

require "delegate"

class Support

  def initialize(prefix)
    @prefix = prefix
    @lines = []
  end

  def write(s)
    @lines << "#{@prefix} #{s}"
  end

  def flush
    @lines.each { |line| puts line }
    @lines = []
  end


end

class Client < DelegateClass(Support)

  def initialize(support)
    super(support)
  end

  def write_header
    write(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>")
  end

  def write_footer
    write(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>")
  end

end

client = Client.new(Support.new("delegate"))
client.write_header
client.write("Hello, World !")
client.write_footer
client.flush