Rubyのクラス何でも出来すぎだろコレ

gistfile1.rb

class Foo
  def hoge
    print "HogeHoge\n"
  end
end

F = Foo.new
F.hoge

class Foo
  def piyo
    print "PiyoPiyo\n"
  end
end

F.piyo

class Foo
  def hoge
    print "Fuga\n"
  end
end

F.hoge

print "-----------------------------\n"

class Bar < Foo
  def huga
    print "HogeraGera\n"
  end
end

B = Bar.new
B.hoge
B.piyo
B.huga

print "-----------------------------\n"

class Foo
  def hoge
    print "HogegeHogeHoge\n"
  end
end

F.hoge
B.hoge