my $text = "Here is [id=327]a very cool document[/id] for you";
$text =~ /\[id=([0-9]*)\](.*)\[\/id\]/i;
my $tag = "<A HREF=\"/cgi-bin/coolcode.pl?id=$1\">$2</A>";
my $before = $`;
my $after = $';

print "$before$tag$after\n";

##</code><code>##

Here is <A HREF="/cgi-bin/coolcode.pl?id=327">a very cool document</A> for you