So thats the accessor code you use. Cool. But wheres the DESTROY? And how do you manage it? Id expect some infrastructure to manage the attributes. Something like:

package Foo;
use Scalar::Util qw(refaddr);
use strict;
use warnings;

BEGIN {
   my @destroy;
   sub DESTROY {
     my $addr= refaddr $_[0];
     foreach my $hash (@destroy) {
        delete $hash->{$addr};
     }
   }
   sub reg_attr { push @destroy,\my %hash; \%hash }
}
BEGIN {
   my $attribute=reg_attr();
   sub get_attribute{ $attribute->{refaddr $_[0]} }
   sub set_attribute{ $attribute->{refaddr $_[0]} = $_[1] }
}
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