From: Michael Libby <michael.c.libby@...>
Date: 2008-11-13T21:45:06+09:00
Subject: Re: '#' characters are breaking my regexp

On Thu, Nov 13, 2008 at 5:21 AM, Max Williams
<toastkid.williams@gmail.com> wrote:
> I'm trying to build a regexp that includes music notes, eg Bb or C#.
> However, the '#' character is breaking them - basically it just stops
> reading the string as soon as it gets to a #:
>
>>> string = "(Ab|Bb|Db|Eb|Gb|A#|C#|D#|F#|G#|A|B|C|D|E|F|G)"
> => "(Ab|Bb|Db|Eb|Gb|A#|C#|D#|F#|G#|A|B|C|D|E|F|G)"
>>> regex = Regexp.new(string)
> => AbBbDbEbGbA
>
> Can anyone explain why this is happening and how to get around it?  Is
> it thinking that the part after the first hash is a comment for example?

The # must be confusing the parser into thinking some #{} style
interpolation is going to happen.

Substitute \# for # and see if that helps. Either way works the same
for me in 1.8.7.

-Michael Libby