From: Anton <selecter@...>
Date: 2007-07-15T19:16:00+09:00
Subject: Re: [QUIZ] Maximum Sub-Array (#131)

On 14/07/07, James Edward Gray II <james@grayproductions.net> wrote:
> On Jul 14, 2007, at 12:21 PM, Anton wrote:
>
> > Hello, everybody! I am new here. I am also relatively new to ruby.
> >
> > I don't know if it's OK to ask questions here before the 48 hours
> > period ends. So I am going to shoot straight and ask.
> >
> > I am trying to create a perfect regexp match string to match an array
> > string like [1, -1, 4, 5]
> > So far the best I've came up with is /^\[-*\d+,*.*\]$/
> >
> > If I add \s+ the string doesn't match. /^\[-*\d+,*\s+.*\]$/ And I have
> > no idea why...
>
> Well, if I understand right, you want a regex to match an array of
> one or more integers?  I would probably use:
>
>    /\A\s*\[\s*-?\d+(?:\s*,\s*-?\d+)*\s*\]\s*\Z/
>
> Is that what you are after?
>
> James Edward Gray II
>

Yes, you understood me right. Your example is what I needed. But I
have one small question. Why is '?' needed at the beginning?
(?:\s*,\s*-?\d+) It seems to me it's the key for a correct match :)