How about: 
my $str = '[id=4590]blahblah[/id]';

$str =~ m/^\[id=(\d+)\](.+)\[/;

print '<a href="/cgi-bin/coolcode.pl?id=' . "$1>$2</a>\n";

[download]
or . . . 
$str =~ s{^\[id=(\d+)\](.+)\[/id]}{<a href="/cgi-bin/coolcode.pl?id=$1
+>$2</a>};
print "$str\n";

[download]
I should mention that you probably will want to take out the carret ^ in both regex's - that tells the engine to start the match at the BEGINNING of the string. Since you are probably going to be extracting this from somewhere in the middle of the document - you don't want this.

Also, don't forget to add the 'g' modifier if you want to get multiple occurrences of the regex.

Update: Big thanks to kudra for reminding me to add $2 !!

Jeff 

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
F--F--F--F--F--F--F--F--
(the triplet paradiddle)

In reply to (jeffa) Re: Monks' Expression by jeffa
in thread Monks' Expression by sinan

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