From: Peter <Peter.Vanbroekhoven@...>
Date: 2003-12-18T04:29:08+09:00
Subject: Re: gsub question

> ruby -e 'a="hello hi hello";a.gsub!(/(\w+)/,"#{$1}a"); puts a'
> a a a
>
> Why?  I'm expecting the same result as in perl.

$1 is evaluated before the matching happens, and since you didn't match
anything yet, $1 is the empty string. Do this instead:

ruby -e 'a="hello hi hello";a.gsub!(/(\w+)/,"\\1a"); puts a'
helloa hia helloa

Peter