My shuffle exercise for Ch. 10 in "Learning to Program" by Chris Pine

shuffle.rb

start_array = []
puts "Enter as many words as you like, pressing Enter after each word has been input. type 'stop' to finish entering words."
while true 
  x = gets.chomp.downcase  #had to put this within the while loop for code to work, not outside while loop
  if x != "stop"     
    start_array.push x 
  else
    def do_shuffle start_array
      shuffle start_array, []
    end

    def shuffle unshuffled, shuffled
      if unshuffled.length <= 0
        puts shuffled
      else
        random = unshuffled.sample
        shuffled << random
        unshuffled.delete(random)

        shuffle unshuffled, shuffled
     end
    end

    do_shuffle(start_array)
  end
end