dci_example.rb

class FetchingProgressInstance  
  attr_reader :enrollment, :roadmap

  def initialize(enrollment, roadmap)
    @enrollment = enrollment
    @roadmap = roadmap
    assign_progress_fetcher(@enrollment)
  end

  def fetch_progress
    enrollment.progress_for(roadmap)
  end

  private

  def assign_progress_fetcher(enrollment)
    enrollment.extend(ProgressFetcher)
  end

  module ProgressFetcher
    def progress_for(given_roadmap)
      if roadmap == given_roadmap
        # return progress
      elsif has_roadmap?(given_roadmap)
        # determine whether the roadmap is for a previous
        # enrollment state or a future enrollment state
        # and return the progress instance for it
      end
    end

    # more methods

  end
end