On Nov 14, 2009, at 8:56 PM, Marnen Laibow-Koser wrote:

> This article is appallingly poorly thought out, and in any case only arns against using typed arguments (hardly possible anyway in Ruby) and 
> using inheritance where composition was actually necessary (a basic OO nalysis mistake).  It brings little or nothing useful to the present iscussion.

I chose an example of the discussion.  It is in no way isolated.  The Gang of Four book is largely about avoiding inheritance.  James Gosling admits that he wishes he could do away with objects for typing in Java, as the article says.  You even stated that types aren't all that important in Ruby, which I agree with, but that seems like and argument against all of your examples that handle all typing with subclassing.

Anyway, I've given examples and provided reference points.  I hope I've made my case.  Now we're probably just bugging people, so I'm going to let it go.