for_socpe.rb

def for_scope(scope, user = GuestUser.new)
	case scope
  	when 'saved'
		user.saved_articles.scoped
  	when 'my'
    		user.tagged_articles.scoped
  	else
    		scoped
  	end
end


# ????????? scoped or none or something else?	

class Guest
	def saved_articles
		Article.scoped
	end
end