From: Ryan Davis <ryand-ruby@...>
Date: 2009-03-10T17:14:13+09:00
Subject: Re: Regexp problem


On Mar 10, 2009, at 00:17 , Albert Schlef wrote:

> I want to extract an "id" parameter from the URL. I use the following
> code:
>
>  url = "http://example.com/id=12345"
>  id = url[ /(?<=id=)(\d+)/ ]
>  puts id
>
> But I get a SyntaxError telling me "undefined (?...) sequence".

(?:...)

not

(?<...)

but really, /(\d+)/ will suffice for your example. see:

see http://www.zenspider.com/Languages/Ruby/QuickRef.html#11