From: Mark Thomas <mark@...>
Date: 2008-09-26T23:14:58+09:00
Subject: Re: Short question on regex in Ruby

On Sep 26, 10:02 am, Chris Ro <kyl...@gmx.net> wrote:
> Hi,
>
> I have a little problem with a regex in Ruby:
>
> I have twos strings:
>
> string1 = "He is the 20th."
> string2 = "25th"
>
> I wrote this to "extract" the place (20 or 25 respectively):
>
> place1 = string1.gsub(/.*(\d+)th.*/,'\1')
> place2 = string2.gsub(/.*(\d+)th.*/,'\1')
> pp place1
> pp place1
>
> => "0"
> => "5"
>
> Of course, I would like to get all the digits before "th". Why is only
> the last one captured?

Because the .* is greedy and will get all it can, which is all but the
last digit.

> If anyone could please explain this, and help me come up with a regex
> that captures 20 and 25, respectively, this would be greatly

place = string[/\d+(?=th)/]

-- Mark.