my @foo = ( 1, 2, 3 );
my $arrayref = \@foo;

##</code><code>##

my $arrayref = [ 1, 2, 3 ];

##</code><code>##

my @foo = ( 1, 2, 3 );

##</code><code>##

my @foo = ( [1], [2], [3] );

##</code><code>##

my $arrayref1 = [ 9, 10, 'a big fat hen' ];

my $arrayref2 = [
    $arrayref1,
    $arrayref1,
    $arrayref1,
];

print "Only showing super-structure:\n";
print Dumper $arrayref2;
print "Showing both sub-structure and super-structure:\n";
print Dumper $arrayref1, $arrayref2;

##</code><code>##

    Only showing super-structure:
    $VAR1 = [
              [
                9,
                10,
                'a big fat hen'
              ],
              $VAR1->[0],
              $VAR1->[0]
            ];
    Showing both sub-structure and super-structure:
    $VAR1 = [
              9,
              10,
              'a big fat hen'
            ];
    $VAR2 = [
              $VAR1,
              $VAR1,
              $VAR1
            ];