concurrent array making with Celluloid

concurrent_array.rb

require 'celluloid'

class ArrayMaker
  include Celluloid
  
  attr_reader :content
  
  def initialize
    @content = []
  end
  
  def add_five
    1.upto 5 do |n|
      @content << n
      sleep 5
    end
  end
end

numbers = ArrayMaker.new

numbers.content
# => []

numbers.add_five!
# => nil

numbers.content
#=> [1]

sleep 10

numbers.content
# => [1,2,3]

sleep 10

numbers.content
# => [1,2,3,4,5]