On Fri, 20 Aug 2010 01:02:56 -0500, Mr zengr <utkarsh2012 / gmail.com>
wrote in <e84b80a0c451613d39971f9a1e8ec4a8 / ruby-forum.com>:

[snip my question about extracting domain name (e.g. "example.com"
from "www.example.com").
>
>I think the best way will be actually match with a list of TLDs and 
>gTLDs.
>
>Mozilla has a list of domains: 
>http://mxr.mozilla.org/mozilla/source/netwerk/dns/src/effective_tld_names.dat

Wow.  That's a big help.  Thanks.

>A stackoverflow question on the same topic: 
>http://stackoverflow.com/questions/569137/how-to-get-domain-name-from-url

Interesting.

>Their solution is regex.

As the poster pointed out, matching everything leads to a huge regex,
which is likely to cause maintenance problems (though he indicated
that they started generating the regex from other data to address
that) and would make me concerned about resource allocation, though I
couldn't find anything in the core Ruby Doc about a max length for a
regex.

On the other hand it might be more performant than looping through a
bunch of substring matches or matching against database records.  I
sense some testing in my future.

Thanks,
-- 
Charles Calvert
Moderator - alt.computer.consultants.moderated
Submission Address: accm / celticwolf.net
Contact Address: accm_mod / celticwolf.net