nesne.rb

#!/usr/bin/ruby
# coding: utf-8
require 'renk'
class Dortgen
  include Unit
  attr_accessor :en, :boy, :alan
  def initialize x, y
    @en = x.to_s + " metre"
    @boy = y.to_s + " metre"
    @alan = (x * y).to_s + " metrekare"
    @renk = nil
  end
end
class Kare
  include Unit
  attr_accessor :en, :boy, :alan
  def initialize *x
    begin
      raise ArgumentError unless x.size == 1
    rescue ArgumentError=>e
      Stderr.puts "ArgumentError: sadece bir kenarinin uzunlugu girilmeli"
    else
      @en = x.to_s + " metre"
      @boy = x.to_s + " metre"
      @alan = (x[0] * x[0]).to_s + " metrekare"
      @renk = nil
    end
  end
end
bir_nesne = Dortgen.new 2, 3
p bir_nesne.en
p bir_nesne.boy
p bir_nesne.alan
bir_nesne.boya :mavi
p bir_nesne.renkli?
bir_nesne.boya :mor
diger_nesne = Kare.new 2, 1
diger_nesne = Kare.new 2
p diger_nesne.en
p diger_nesne.boy
p diger_nesne.alan
p diger_nesne.renkli?

renk.rb

#!/usr/bin/ruby
# coding: utf-8
module Unit
  def boya renk
    renkler = [:kirmizi, :mavi, :sari, :yesil]
    begin
      raise TypeError unless renkler.include?(renk)
    rescue TypeError=>e
      $stderr.puts "TypeError #{renkler} disinda boya yok"
    else
      @renk = renk
    end
  end
  def renkli?
    return true if @renk
    return false
  end
end