From: Joel VanderWerf <vjoel@...>
Date: 2002-03-13T02:07:27+09:00
Subject: Re: Method type 'abstract'

Peter Hickman wrote:
...
> override this method. In Java I would mark the method as abstract rather
> than just public or private and when I subclass it the compiler would
> choke if I did not provide the override in the subclass.

In Ruby, adding methods is dynamic, so the compiler can never be sure
that you aren't going to provide the override at some point in the
future. So the Ruby way to detect this is at "run time", i.e. with a
superclass method that raises an exception.