It looks like (?: .. ) is something special and is not returning a numbered variable so all we get out are two variables $1 and $2 used respectively in the hash as the key and value?

You bet. ;-) The ?: in the bracket tells Perl not to capture the pattern inside the bracket. You can find the documentation on (?:pattern) on the CPAN perlre documentation here

  And could I check for a string contain anything from a list?

Well, yes you can. The method I use is to construct the search pattern with a join, as the following example demonstrates -

my $something = 'This is a bang of a bing thing';

my @list = qw /bing bong bang/; # want to search for these
my $list = join '|', @list;     # construct my pattern

if($something =~ m/($list)/i) {
  print "Found '$1' in '$something'\n";
}
[download]

If you want to capture all occurances of the patterns, you could use the @array = $str =~ m/pattern/g idiom.

my @search = $something =~ m/($list)/ig;  # <- added the g modifier
[download]

or you could do this in a while loop -

while ($something =~ m/($list)/ig) {
    print "Found '$1' in '$something'\n";
}
[download]

The problem with your code is that m/(@list)/i is looking for the pattern of the interpolated list items, the pattern "bing bong bang", in the string, and of cause it is not found.

use strict;

my $something = 'This is a bang of a bing thing bing bong bang';

my @list = qw / bing bong bang /;

if ($something =~ m/(@list)/i) {
    print "Found '$1' in '$something'\n";
}
[download]

And the output is -

Found 'bing bong bang' in 'This is a bang of a bing thing bing bong ba
+ng'
[download]

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.