From: Austin Ziegler <halostatue@...>
Date: 2005-08-10T21:49:40+09:00
Subject: Re: NEWBIE QUESTION: pattern with nil

On 8/10/05, BearItAll <bearitall@rassler.co.uk> wrote:
> On Wed, 10 Aug 2005 14:44:15 +0900, John Carter wrote:
> > class NilClass
> >    def empty?
> >      true
> >    end
> > end
> > if a.empty?
> I vote for this one because a good programmer is a lazy sod. Where ever
> you would end up doing a thing more than once, write it is such a way that
> you never have to type it again.

Just, please, don't do it in a library that you unleash on the rest of
the world. It changes the contract for +nil+, and I prefer that it
*not* respond to #empty?, because the concept isn't *quite* accurate.
One may as well define #zero? if you're going to to that (but +nil+
isn't zero, either, just as it isn't the empty string or array).
Better is to use the foo.nil? or foo.empty? construct and be explicit,
or foo.to_s.empty? if you want to silently cast ("normalize").
Changing nil to respond to #empty? is an implicit change that also
changes its meaning.

-austin
-- 
Austin Ziegler * halostatue@gmail.com
               * Alternate: austin@halostatue.ca