gistfile1.txt

class ApplicationController
  def current_user_decorator
    @cud ||= current_user ? CurrentUserDecorator.new(current_user) : NullCurrentUserDecorator.new
  end
  
  # or this
  def current_user
    if signed_in?
      super
    else
      @cud ||= NullCurrentUser.new
    end
  end
end



class CurrentUserDecorator
  def initialize(current_user)
    @current_user = current_user
  end
end

class NullCurrentUserDecorator
  def initialize
    # nothing here
  end
  
  def movies
    []
  end
end