Ruby dice lib => https://www.reddit.com/r/ProgrammingPrompts/comments/2luobv/game_component_die_and_dicebag/

dicelib.rb

module DiceLib

  class Dice
    attr_accessor :hold, :current, :last

    def initialize sides = 6
      @dice = (0 .. (sides-1)).to_a
      @hold = false
      @current = @last = rand(@dice.length)
    end

    def roll
      @last = @current
      @current = rand(@dice.length) if !@hold
      @current
    end

  end

  class DiceBag
    attr_accessor :dices

    def initialize dices = nil; @dices = dices || []; end
    def add dice; @dices << dice; end
    def delete dice; @dices.delete(dice); end

    def hold_all; @dices.each { |dice| dice.hold = true }; end
    def release_all; @dices.each { |dice| dice.hold = false }; end

    def roll_all
      @dices.each { |dice| dice.roll }
      @dices.collect { |dice| dice.current }
    end
  end

  module Display
    @dice  = "+----+\n"
    @dice += "| XX |\n"
    @dice += "+----+\n"
    def self.render val
      if val.is_a? Integer
        return @dice.gsub("XX", "%02d" % val)
      elsif val.is_a? Array
        out = ""
        val.each do |value|
          out += @dice.dup.gsub("XX", "%02d" % value)
        end
        out
      end
    end

  end

end

example.rb

dice = DiceLib::Dice.new 
puts dice.roll # number between 0-5
dice2 = DiceLib::Dice.new 8
dice3 = DiceLib::Dice.new 22

dicebag = DiceLib::DiceBag.new [dice, dice2]
dicebag.add dice3
dicebag.delete dice
p dicebag.roll_all
dicebag.hold_all
p dicebag.roll_all
dicebag.release_all
p dicebag.roll_all

puts "Graphical dicebag:"
puts DiceLib::Display.render dicebag.roll_all

puts "Graphical single:"
puts DiceLib::Display.render dice.current