From: Farrel Lifson <farrel.lifson@...>
Date: 2006-10-06T21:30:21+09:00
Subject: Re: nil being empty

On 06/10/06, David Chelimsky <dchelimsky@gmail.com> wrote:
> Doesn't it depend on context? The other responders seem to suggest
> that is objectively bad form, with which I  can agree (generally), but
> in a case like this:
>
> collection.select do |item|
>   item.respond_to?(:empty?) and (!item.empty?)
> end
>
> I might prefer
>
> collection.select do |item|
>   true unless item.empty?
> end
>
> or this (which, though more terse, I personally find less readable)
>
> collection.select do |item|
>   !item.empty?
> end
>
> One of the beauties of the language (for me) is that language
> invariants become somewhat less "in" and more "variant".
>
>

You could make it slightly  more elegant with an extra function call
 collection.select.do |item|
   !Array(item).empty? #Could also use !String(item).empty depending
on what item is
 end

Farrel