Delaying size of the apple until after initialization

apple.rb

module Fruit

  class Apple
    attr_reader :variety, :created_at

    def initialize(variety = default_variety)
      @variety = variety
      @created_at = Time.now
    end

    def initial_size
      rand(5..9)
    end

    def slices
      @slices ||= [1] * initial_size
      @slices
    end

    def slice(number=1)
      slices.pop(number).count
    end

    def remaining_slices
      slices.count
    end

    def default_variety
      "Granny Smith"
    end

    def age
      Time.now - created_at
    end

    def ripe?
      age > maturity_time
    end

    def unripe?
      !ripe?
    end

    def maturity_time
      10.0
    end
  end

end