From: Danny O cuiv Date: 2009-05-08T02:17:43+09:00 Subject: Re: Superclass of eigenclass Hi Rick, I suspect that you're right that the text is incorrect. I doubt that it's a typo (in the sense of something that was fat-fingered) as the three sentences, taken together, are consistent in what they express. As such, it seems mistaken, which makes me curious to know what they were intending to say. Your investigation of the issue corresponds with mine. I would, however, take issue with an aspect of your revised wording, specifically the following: > The eigenclass of an ordinary object can have neither a subclass, > nor any other instance except that single ordinary object. The ordinary object is not an instance of the eigenclass. In your example, the ordinary object is an instance of TestClass, not of any eigenclass. Indeed, there would be a bootstrapping problem if you regarded the ordinary object as an instance of the eigenclass. (You can only have an eigenclass in the context of an existing object, so you couldn't have created that object in the first place by instantiating the eigenclass.) The same issue appears in the following statement: > If it is cloned with the Object#clone method, the result will get an eigenclass > which is a duplicate of the original objects eigenclass, so that each > eigenclass has but a single instance." Regards, Danny -- Posted via http://www.ruby-forum.com/.