From: Daniel Amelang <daniel.amelang@...>
Date: 2005-08-28T14:12:35+09:00
Subject: Re: Reopening with a bang: cannot assign to self

I see. Well, there isn't a general way to do it in any class, since
some classes (like Fixnum) are immutable.

For most classes, though, there will be a way to do what you want by
finding a 'replace'-like method.

Dan