From: Lars Haugseth <njus@...>
Date: 2009-08-05T19:05:13+09:00
Subject: Re: remove commas from string

* Jason Lillywhite <jason.lillywhite@gmail.com> wrote:
> 
> I have following string:
>
> s = "B747-400, 8,357 miles, 561 mph, 4 Pratt & Whitney PW 4056
> turbofans, 56,000 lbs."
>
> I want to remove the comma only from the numbers (8,357 miles and 56,000
> lbs) separating the thousands. I want the string to read as follows:
>
> "B747-400, 8357 miles, 561 mph, 4 Pratt & Whitney PW 4056 turbofans,
> 56000 lbs."

Ruby 1.9 supports look-behind in regular expressions (Ruby 1.8
only supports look-ahead):

 $ irb1.9

 irb(main):001:0> s = "B747-400, 8,357 miles, 561 mph, 56,000 lbs."
 => "B747-400, 8,357 miles, 561 mph, 56,000 lbs."

 irb(main):002:0> s.gsub(/(?<=\d),(?=\d)/, '')
 => "B747-400, 8357 miles, 561 mph, 56000 lbs."

-- 
Lars Haugseth