Ruby inheritance, modules or subclasses
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I'm working with the Tumblr API right now and they have various types of posts (text, photo, video, quote, link, etc.). I'd like to make one parent class TumblrPost and then a bunch of sub-classes such as TumblrTextPost. If I do this, would there be a way to access each post via TumblrPost (ie. TumblrPost.all.each) regardless of sub-class? (NOTE: I'm using MongoDB and Mongoid)

Or should I maybe make each sub-class a module and then just do class TumblrPost include TumblrTextPost, etc.?