From: Markus Roberts <Markus@...>
Date: 2009-10-04T04:12:43+09:00
Subject: Re: On Ranges as conditions

It isn't a range, it's a "flip-flop" which happens to use the same  
operator ('..') as range construction.

While useful in some sed/awk like scripts it's not a widely used  
feature.

-- MarkusQ