outer-product.pl

use v5.18;
use strict;
use warnings;

my @p;

my @va = ("x", "y", "z");
my @vb = ("p", "q");

for my $va (@va) {
    for my $vb (@vb) {
        push @p, [$va, $vb];
    }
}

say "@$_" for @p;