How to find each instance of a class in Ruby

Question

Is there a way to get all the objects that are of a certain class in Ruby?

To clarify:

class Pokemon
end

pikatchu = Pokemon.new
charmander = Pokemon         


        

Answer 1

Yes, one could use ObjectSpace, but in practice one would simply keep track of instances as they are created.

class Pokemon
  @pokees = []
  self.class.public_send(:attr_reader, :pokees)

  def initialize
    self.class.pokees << self
  end
end

pikatchu = Pokemon.new
  #=> # 
charmander = Pokemon.new
  #=> # 
Pokemon.pokees
  #=> [#, #]