use strict;
use warnings;
use Regexp::Common qw(URI);

my $URI = $RE{URI}{HTTP}{-keep};

my @uris = (
            'http://yahoo.co.uk/notfound.html',
            'http://yahoo.co.uk:80/notfound.html?fn=john&ln=doe',
            'http://yahoo.co.uk/',
            'http://yahoo.co.uk',
            'yahoo.co.uk/notfound.html',
            'yahoo.co.uk',
            'potato://yahoo.co.uk',
            );

## Extract the host from the sample urls above
for my $uri (@uris) {
    my (
        $whole, $scheme, $host, $port,
        $path_q_slash, $path_q_noslash, $path_noq_noslash,
        $query,
        )
        = ($uri =~ $URI);

    if (defined $whole) {
        printf "%-50s => %s\n", $whole, $host;
    }
    else {
        printf "%-50s => No match\n", $uri;
    }
}

##
## An example with all the pieces:
##     'http://yahoo.co.uk:80/notfound.html?fn=john&ln=doe'
##
my $uri = $uris[1];
my ($whole, @bits) = ($uri =~ $URI);
printf "\n%s =>\n    %s\n", $whole, (join qq(\n    ), @bits );

__END__

##</code><code>##

http://yahoo.co.uk/notfound.html                   => yahoo.co.uk
http://yahoo.co.uk:80/notfound.html?fn=john&ln=doe => yahoo.co.uk
http://yahoo.co.uk/                                => yahoo.co.uk
http://yahoo.co.uk                                 => yahoo.co.uk
yahoo.co.uk/notfound.html                          => No match
yahoo.co.uk                                        => No match
potato://yahoo.co.uk                               => No match

http://yahoo.co.uk:80/notfound.html?fn=john&ln=doe =>
    http
    yahoo.co.uk
    80
    /notfound.html?fn=john&ln=doe
    notfound.html?fn=john&ln=doe
    notfound.html
    fn=john&ln=doe