How about this using URI::Find ...

#!/usr/bin/perl -Tw

use URI::Find;
use strict;

my $text = " ... long string with lots of URLs ... ";

my @urls;
find_uris($text, sub {
    my ($uri, $orig_uri) = @_;
    push @urls, $orig_uri;
});

print join("\n", @urls), "\n";
exit 0;
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Note that the CPAN documentation for URI::Find is out-of-date with the newest version (0.04) exporting only the one function, find_uris, which takes two arguments, the string to be searched and a function reference.

 

perl -e 's&&rob@cowsnet.com.au&&&split/[@.]/&&s&.com.&_&&&print'