From: James Edward Gray II <james@...>
Date: 2006-03-08T05:06:21+09:00
Subject: Re: Is there link extractor or similar html processing libs for Ruby

On Mar 7, 2006, at 1:36 PM, Bill Kelly wrote:

> From: "James Edward Gray II" <james@grayproductions.net>
>> >
>> > You meant something like this ? (quite dirty but works)
>> >
>> > puts open("some.html").read.scan(/<a href="?(.+?)"?>/)
>> No, it doesn't, trust me.  ;)  Toss a simple "\n" in there and  
>> you're  sunk:
>> <a
>>   href="whatever">
>> Parsing HTML is hard and you don't want to use regular expressions  
>> to  do it.
>
> Hi, not trying to be argumentative, just surprised.  I thought  
> parsing HTML with regexps was pretty easy.  Well, lexing HTML into  
> tokens, I mean.

There's a lot of pretty darn ugly HTML out there my friend.  Here's a  
semi-paranoid attempt to grab just the start of anchor tag:

/<\s*a[^>]*?href\s*=\s*(['"]?)[^'"]*\1?[^>]*>/i

Am I getting close yet?  No, the quotes are all wrong.  That would  
fail to match an extremely common link like:

<a href="alert('You broke it!')">

I would try to fix that, but my brain has already melted and leaked  
out my ear.  :)  I'm sure I made other mistakes too.

If you want to capture the name of the link too, this gets *much* worse!

James Edward Gray II