in reply to Tidying up some dereferencing code

You can also replace:
for (my $i = 0; $i < @$ref - 1; $i++) {
with:
for my $i (0..$#$ref) {

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)