This is a set operation (set difference), not a list operation.

This is a set operation (set difference), not a list operation.

Sure it is a set operation. As is uniq, or even max. You could want to do the same operation to hashkeys, or to a CSV string. But the most common way that the set-difference problem shows up is as the set difference between two lists.

If not List::MoreUtils, I'm still surprised it isn't in one of the common modules.

throop

use strict;
use warnings;
use List::Compare;

my @dbs = qw(fetch forward user smtp);
my @skip_dbs = qw(user smtp);

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

my @list = $lc->get_unique;

print @list;
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Cheers,

Brent