frozen_string.rb

class FrozenString
  module ClassMethods
    def get(string)
      @@repository ||= {}
      @@repository[string.freeze] ||= new(string.freeze)
    end
  end
  extend ClassMethods

  def initialize(string)
    @value = string
  end

  def to_str
    @value
  end

  alias_method :to_s, :to_str

  class << self
    private :new
  end
end

The implementation looks good, just missing some tests hehe. I can take a spin to this later on.

Any reason why not just do def this.get ? Code style ?