The hash example -- not sure what you are referring to, specifically.

chromatic probably meant something like:

c:\@Work\Perl\monks\AnomalousMonk>perl -wMstrict -le
"my %hash = (
   foo => [1, 2, 3, 4],
   bar => [3, 5, 7],
   );
 ;
 elements(\%hash, qw(bar foo));
 ;
 sub elements {
   my $hashref = shift;
   for my $name (@_) {
     print qq{elements of $name: }, scalar @{ $hashref->{$name} };
     }
   }
"
elements of bar: 3
elements of foo: 4
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