elements from array @a that are not in array @b

Here's another option for that:

use Modern::Perl;
use List::Compare;

my @a = 1 .. 10;
my @b = 5 .. 14;

my $lc = List::Compare->new(\@a, \@b);

say $lc->get_unique;
[download]

Output:

1234
[download]

ps Aaron, I always appreciate your postings...