From: Greg Hurrell <greg.hurrell@...>
Date: 2007-02-15T03:40:06+09:00
Subject: Re: Programmatically turning a Regexp into an anchored Regexp

On 14 feb, 19:06, Wolfgang N�dasi-Donner <won...@donnerweb.de> wrote:
>
> irb(main):004:0> "foo at the beginning".gsub(/^#{r1}/, '###')
> => "### at the beginning"
> irb(main):005:0> "the foo in the middle".gsub(/^#{r1}/, '###')
> => "the foo in the middle"

Thanks, Wolfgang. I had no idea that #{} could be used not only to
interpolate within literal Strings, but within Regexps as well. I now
see that it's noted on page 66 of The Pickaxe... "In addition, a
regular expression may contain #{...} expression substitutions."

I tried it out and I see that it also works even if the original
Regexp already has a "^" in it...

Cheers,
Greg