Well, putting aside your desire to match the "important" part of a domain name, you probably want to use a regex that says "match and save a set of non-. characters that are followed by a ., then non-. and non-/ characters, and then either a / or the end of the string".

Basically, you want to ensure you're a) only looking at the domain name, and b) getting the penultimate .-separated sequence.

It would probably be more intuitive to use two split()s: 
($domain) = split '/', $string;
$wanted = (split /\./, $domain)[-2];

# or

$wanted = (split /\./, (split '/', $string)[0])[-2];

[download]
Here's the regex approach: 
($wanted) = $string =~ m{
  ( [^.]+ )   # save the non-. sequence to $1
  \.          # .
  [^./]+      # the final non-. non-/ sequence
  (?: / | $)  # / or the end of the string
}x;

[download]


japhy -- Perl and Regex Hacker

In reply to Re: pattern matching by japhy
in thread Creating a regex to match part of a URL's domain name (was: pattern matching) by strfry()

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