my $abcees = iter(qw(a b c));
my $xyzees = iter(qw(x y z));

enumerate_iter(
    iter_prod( $abcees, $xyzees )
);
#  0: (['a','x'])
#  1: (['a','y'])
#  2: (['a','z'])
#  3: (['b','x'])
#  4: (['b','y'])
#  5: (['b','z'])
#  6: (['c','x'])
#  7: (['c','y'])
#  8: (['c','z'])