From: Eric Hodel <drbrain@...7.net>
Date: 2009-03-28T19:00:49+09:00
Subject: Re: Regular Expression interesting problem

On Mar 28, 2009, at 02:07, Arun Kumar wrote:
> Hi,
> I'm learning about regular expressions right now for a html scraping
> based assignment. But now I've reached a problem. Given below are two
> different html tags.
>
> <link
> href="http://newsrss.bbc.co.uk/rss/newsonline_world_edition/help/rss/rss.xml 
> "
> rel="alternate" type="application/rss+xml" title="BBC NEWS | Help |  
> RSS"
> />
>
> <link rel="alternate" type="application/rss+xml" title="YouTube - Top
> Favorites Today"
> href="http://gdata.youtube.com/feeds/base/standardfeeds/top_favorites?client=ytapi-youtube-index&time=today&v=2 
> ">
>
> Now what i want is to capture the href-url if the type =
> "application/rss+xml". It seems to be simple but it is the position of
> the 'type' that creates the problem. In first tag the 'type' is after
> href and in the second the 'type' is before it. It seems to me as an
> interesting problem, but i need help for solving it. Please help me.

I suggest you use Nokogiri.

Barring that, don't use regular expressions, use something more  
appropriate like StringScanner from strscan.rb.  `ri StringScanner`  
will get you started.

PS: You'll probably want to do something like scan for <, then scan  
for a tag name, then scan for attributes, then scan for >, etc.

PPS: There's no need to post twice.