Hi bluray!

It looks to me like you paid attention to the suggestions in the previous post! I don't see anything glaring wrong here. If this does what you want functionally, I don't see a reason to keep tweaking. (well, I would spiff up the indenting) - but structurally, you have sound code.

If you are asking if

my $revcomp=reverse($1);
$revcomp=~tr/ACGTacgt/TGCAtgca/;
[download]

is fine, it is. reverse() is fast and tr is much faster than any other way to do a one->one character mapping. If you want to convert to all uppercase at the same time, $revcomp =~ tr/ACGTacgt/TGCATGCA/;