Please advice with, I have some models and they have feeds, feed is a small presenter for different types of content.
class Feed belongs_to :attachable, :polymorphic => true end
class Song has_one :feed, :as => :attachable end
class Gallery has_one :feed, :as => :attachable end
So when I call on some_song.feed, and there is no such feed for that song, I want to create it inside Feed model