From: gwtmp01@...
Date: 2005-11-18T06:26:51+09:00
Subject: Re: Object#to_b


On Nov 17, 2005, at 3:04 PM, Jeremy Kemper wrote:
> Right: I had to dig as far as RTEST when I tried to act like nil
> to understand why it did not work.  I was happy to see that it's
> very fast but was unhappy to discover the "line in the sand" between
> dynamic, expressive Ruby and its concern for raw performance.

I think one of the interesting/useful features of Ruby is its
handling of boolean values.  In thinking about the original post,
I came across a nice discussion of nil, null, and false in object
oriented languages, in particular Smalltalk and Objective-C.

http://www.smalltalkchronicles.net/edition2-1/null_object_pattern.htm

I really like the null object pattern but I'm not sure I'm ready
to fully embrace it with a generalized null object and even then I'm
not sure how I think that should fit with nil/false.

My hunch is that either you have a generalized null object that is
considered false or you don't have it.  The idea of having user-defined
false objects just seems to be a opening a Pandora's box of issues.

Gary Wright