my_class_keywords.rb

# Please rewrite the MyString definition, without using ruby keywords 
# http://www.ruby-doc.org/docs/keywords/1.9/

MyString = Class.new(String) {
  define_singleton_method(:alphabet) {
    'abc'
  }

  define_method(:exclaim) { |*args|
    count = args.first || 1
    "#{self}#{exclamation_mark count}"
  }

  define_method(:!) { |*args|
    exclaim *args
  }

  define_method(:exclamation_mark) { |count|
    '!' * count
  }
  self.send :private, :exclamation_mark
}

j = MyString.new('james')

j.exclaim         # "james!"
j.exclaim(4)      # "james!!!!"
j.!               # "james!"

MyString.alphabet # "abc"