From: "Aaron D. Gifford" <astounding@...>
Date: 2011-03-26T21:33:59+09:00
Subject: Re: shortcut for add unless nil ?

An alternative for the original poster's ENV variables potentially
containing colon-separated paths:

 %w{FOO BAR BAZ}.map{|x| ENV[x].to_s}.join(':').split(/:+/)

The .to_s should handle nil just fine. Concatenate all the strings,
then do the split.

Aaron out.