From: Stefano Crocco <stefano.crocco@...>
Date: 2009-11-22T00:12:04+09:00
Subject: Re: Removing optional white space

On Saturday 21 November 2009, Philip Rhoades wrote:
> |People,
> |
> |I want to change:
> |
> |	To: phil
> |
> |or:
> |
> |	To:phil
> |
> |into:
> |
> |	phil
> |
> |- I can do this with two gsubs - is it possible to do it with one?
> |
> |Thanks,
> |
> |Phil.
> |

This should work. The regexp searches for the string To: followed by any 
number of whitespaces (including 0) followed by a letter. Since a positive 
look-haead is used for the letter, it isn't replaced.

s1 = "To: phil"
s2 = "To:phil"
reg = /To:\s*(?=\w)/
s1.gsub(reg,'')
s2.gsub(reg,'')

If you are sure that there can be at most one whitespace after the :, you can 
replace \s* (which matches any number of whitespaces) with \s?, which matches 
zero or one whitespaces.

I hope this helps

Stefano