Update both instance variable and class variable : Class Variables « Class « Ruby






  1. Ruby
  2. Class
  3. Class Variables

Update both instance variable and class variable

class Song
  include Comparable
  @@plays = 0
  attr_reader :name, :artist, :duration
  attr_writer :duration
  def initialize(name, artist, duration)
    @name     = name
    @artist   = artist
    @duration = duration
    @plays    = 0
  end
  def to_s
    "Song: #@name--#@artist (#@duration)"
  end
  def play
    @plays  += 1   # same as @plays = @plays + 1
    @@plays += 1
    "This  song: #@plays plays. Total #@@plays plays."
  end
end

s1 = Song.new("Song1", "Artist1", 234)  # test songs..
s2 = Song.new("Song2", "Artist2", 345)
s1.play
s2.play
s1.play
s1.play








Related examples in the same category

1.Creating Class Variables
2.Class variable and instance variable with the same name