This tests for duplicate entries and suggests a name with the next greatest number attached to the end. It then prompts the user to enter a new one or say yes to the one suggested.

NewEntryDupTest.rb

module NewEntryDupTest

  attr_accessor :entry, :old_entries

  # def initialize(*args)
  #   @old_entries ||= [] 
  #   @entry = :entries 
  # end

  @@old_entries = ['Homer']

  def self.set(old_entries)
    @@old_entries = old_entries
  end

  def self.get
    @@old_entries
  end

  def new_entry(entry)
    @@old_entries.include?(entry) ? suggest_name(entry) : register_entry(entry)
  end

  def register_entry(newest_entry)
    @@old_entries << newest_entry
    "#{newest_entry}"
  end

  def suggest_name(entry)
    until @@old_entries.include?("#{entry + ( nums ||= 0 ).to_s }") == false
      nums = increase_nums(nums)
    end
    prompt_user("#{entry + ( nums ||= 0 ).to_s }")
  end

  def increase_nums(num)
    num += 1
  end

  def prompt_user(new_entry)
    puts "Already Taken,type yes if you would like to save as #{new_entry}"
      input = gets.chomp.downcase
      if input == "yes"
        register_entry(new_entry)
      else
        puts "Please retry with a different name for #{self.class}"
        try_again = self.class.new
        input = gets.chomp
        try_again.new_entry(input)
      end
  end

end

class UserName

  include NewEntryDupTest

end

user = UserName.new
NewEntryDupTest.set(["Bart0","Bart4", "Bart5", "Bart6", "Bart7", "Bart8", "Bart9", "Bart10",
 "Lisa", "Marge", "Homer", "Bart", "Bart1", "Bart2", "Bart3",
 "Bart11", "Bart12"])
user.new_entry('Bart')