Ruby/Class/instance variables

#!/usr/bin/env ruby
class Names
  def initialize( given, family, nick, pet )
    @given = given
    @family = family
    @nick = nick
    @pet = pet
  end
# these methods are public by default
  def given
    @given
  end
  def family
    @family
  end
# all following methods private, until changed
  private
  def nick
    @nick
  end
# all following methods protected, until changed
  protected
  def pet
    @pet
  end
end
class Address < Names
  attr_accessor :street, :city, :state, :country
end
a = Address.new("a","b","c","d")
puts a.respond_to?(:given_name)

#!/usr/bin/env ruby
class Repeat
  @@total = 0
  def initialize( string, times )
    @string = string
    @times = times
  end
  def repeat
    @@total += @times
    return @string * @times
  end
  def total
    "Total times, so far: " + @@total.to_s
  end
end
data = Repeat.new( "a ", 8 )
ditto = Repeat.new( "A! ", 5 )
ditty = Repeat.new( "R. ", 2 )
puts data.repeat
puts data.total 
puts ditto.repeat
puts ditto.total 
puts ditty.repeat
puts ditty.total

# An instance variable is one in which you can store the data in an object - an instance of a class is an object. 
# Instance variables hold their values for as long as the object is in existence. 
# That"s what helps make objects self-contained: the capability to store data.
 
class Animal
  def initialize
    @color = "red"
  end
end

class Hello
  def initialize( name )
    @name = name
  end
  def hello_matz
    puts "Hello, " + @name + "!"
  end
end
hi = Hello.new( "Matz" )
hi.hello_matz # => Hello, Matz!

# An instance variable is a variable that is referenced via an instance of a class
# An instance variable belongs to a given object. 
# An instance variable is prefixed by a single at sign (@)
class Animal
  def initialize(color)
    @color = color
  end
  def get_color
    return @color
  end
end
animal = Animal.new("brown")
puts "The new animal is " + animal.get_color