I have what's probably a simple question for my fellow monks, but Regular Expressions is one of my weaknesses, I am just unable to wrap my head around anything more than only the basics.

my $var =~ m/\w/i;

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Thus poses my problem. I need a rather complicated regex, I need to be able to extract a domain name from a string which could be anything from a full url:

http://www.perlmonks.org/?node=Seekers%20of%20Perl%20Wisdom

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or an email address, or even a bare string:

www.sub.sub2.domain.com
domain.com
ftp.domain.co.uk
adsl-44-33-22-11.dsl.bcvloh.sbcglobal.net

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and I actually would like it to return two results, provided the entered string was more than just domain.com. Using the last line as my example I would need the 2 results to be:

gcvloh.sbcglobal.net
sgcglobal.net

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also, I'd need to make sure that if an international domain name or URL were given, it checked for it and returned:

some.domain.com.au
domain.com.au

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Again provided the string was more than just domain.com.br and if only the bare minimum was entered:

domain.com
domain.co.uk
domain.fm
domain.name
..etc, etc..

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Now I've searched and read a couple of nodes here, that are very similar to this question, but aren't quite enough for me to work with to achieve my goal. One splits up a domain name domain.com to extract domain and the other only focuses on http:// URLs only, and I've Searched Google and the results I've found again don't quite give enough for me to work with, as I am rather dense when it comes to regex.

Many Thanks Fellow Monks,

jnbek

=== Update ===

Looks like actually I have been looking at this from the wrong angle. I have managed to make myself feel like the silly n00b that I am. I only need a regex to strip off extra characters from the front and back, basically between the /'s. Strip off http://|ftp:// etc, then strip the right end / or ? or # then use the pop() function a couple times with a join to get the domain name. So, be it sub1.sub2.sub3.foo.bar.www.domain.com or domain.com I get domain.com to work with. I've only got initial test code with the pop() usage: 

 my $d = "spam.yomama.www.zoelife4u.org";
 my @domain = split(/\./, $d);

 my $tld = pop(@domain); #org
 my $baredomain = pop(@domain); #zoelife4u

 my @result = ( $baredomain, $tld );
 $maindomain = join("\.", @result);
 
 print "End: $maindomain\n;"

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And I think I've found a useful regex to work with here. Based on this, anyone have any critique?

In reply to Regex for extracting a domain name from a string. by jnbek

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