My recursive sort exercise. I updated it to display the end result slightly neater than was asked for in the book.

my_sort.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  #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 sort start_array # This "wraps" recursive_sort. 
      recursive_sort start_array, []
    end
    def recursive_sort unsorted, sorted
      if unsorted.length <= 0 #if there's nothing left to sort
        return sorted
      end

      smallest = unsorted.pop
      still_unsorted = [] #a place for rejects to go
      unsorted.each do |test_word|
        if test_word < smallest
          still_unsorted.push smallest
          smallest = test_word
        else
          still_unsorted.push test_word
        end
      end
        #now smallest points to the smallest word from the group of start array items left to sort
        sorted.push smallest #remove the smallest from the recursive process and put it in its place in the sorted array
        recursive_sort still_unsorted, sorted #now we pass the still unsorted numbers back to the method in the same way
    end
    puts "Your sorted array:"
     final_array = sort(start_array) 
     final_array.each do |y|
       if y == final_array[-1]
         puts y
         break
        else
          print y + ', '
        end
      end
    break
  end
end