Perl 正規表現でURLをリンクに置換する

#!/usr/local/bin/perl -w
use strict;

my $text;

$text =<<TEXT;
http://www.yahoo.co.jp/
日本語http://www.yahoo.co.jp/
http://www.yahoo.co.jp/ ヤフー
http://www.yahoo.co.jp/ヤフー
https://login.yahoo.co.jp/ヤフー
URL: http://www.yahoo.co.jp/
URL: http://www.yahoo.co.jp/#
URL: http://www.yahoo.co.jp/#hoge
URL: http://www.yahoo.co.jp/?foo=bar&a=1#hoge
ftp: ftp://ftp.freebsd.org/
ftp: ftp://ftp.freebsd.org/pub/
ftp: ftp://ftp.freebsd.org/pub
TEXT

my $http_URL_regex =
q{\b(?:https?|shttp|ftp)://(?:(?:[-_.!~*'()a-zA-Z0-9;:&=+$,]|%[0-9A-Fa-f} .
q{][0-9A-Fa-f])*@)?(?:(?:[a-zA-Z0-9](?:[-a-zA-Z0-9]*[a-zA-Z0-9])?\.)} .
q{*[a-zA-Z](?:[-a-zA-Z0-9]*[a-zA-Z0-9])?\.?|[0-9]+\.[0-9]+\.[0-9]+\.} .
q{[0-9]+)(?::[0-9]*)?(?:/(?:[-_.!~*'()a-zA-Z0-9:@&=+$,]|%[0-9A-Fa-f]} .
q{[0-9A-Fa-f])*(?:;(?:[-_.!~*'()a-zA-Z0-9:@&=+$,]|%[0-9A-Fa-f][0-9A-} .
q{Fa-f])*)*(?:/(?:[-_.!~*'()a-zA-Z0-9:@&=+$,]|%[0-9A-Fa-f][0-9A-Fa-f} .
q{])*(?:;(?:[-_.!~*'()a-zA-Z0-9:@&=+$,]|%[0-9A-Fa-f][0-9A-Fa-f])*)*)} .
q{*)?(?:\?(?:[-_.!~*'()a-zA-Z0-9;/?:@&=+$,]|%[0-9A-Fa-f][0-9A-Fa-f])} .
q{*)?(?:#(?:[-_.!~*'()a-zA-Z0-9;/?:@&=+$,]|%[0-9A-Fa-f][0-9A-Fa-f])*} .
q{)?};

$text =~ s/($http_URL_regex)/<a href="$1">$1<\/a>/g;

print $text, "\n";