Instead of using the x operator, we could have used the
the && operator. The advantage here is that it codes simpler,
and the disadvantage is it has no movable parts (since it is not an array).
in reply to Secret Perl Operators: the boolean list squash operator, x!!
no strict; no warnings;
my $part = 'http://example.net/app'
. ($admin && $is_admin_link)
. (defined $subsite && $subsite)
. (defined $id && $id)
. (defined $submode && $submode)