小编uri*_*rie的帖子

为什么下面给出了以下输出？$a1 定义...

package A1;
use Hash::Merge;
use Data::Dumper;
  
sub new 
{
    my $class = shift;
    my $self =
    {
        length => 2,
    };
    return bless $self, $class;
}

1;


my $a1 = A1->new();
print("a1 = " . ref($a1) . "\n");

my %a = {'1' => $a1};

my $a3 = \%a;
print( Dumper($a3));

输出：

a1 = A1
$VAR1 = {
          'HASH(0x247c568)' => undef
        };

我原以为该值是“A1(0x...)”，而不仅仅是未定义的...