use v5.20;
use Operator qw{in};
use Variables qw{X Y Z};

my @list = 1..10;

(X, Y) = (1, 11);
say X." in @list" if X in @list; 
say Y." not in @list" unless Y in \@list;

Z = 'A';
say Z." in list" if Z in ['A'..'C'];