package InOutObj;

use strict;
use warnings;
use Scalar::Util qw( refaddr );
{
    my %data;

    sub new
    {
        return bless \do{ my $dummy }, shift;
    }

    sub get
    {
        my $self = shift;

        return $data{ refaddr $self };
    }

    sub set
    {
        my ( $self, $arg ) = @_;

        $data{ refaddr $self }{upper} = uc $arg;
        $data{ refaddr $self }{lower} = lc $arg;

        return;
    }

    sub DESTROY
    {
        my $self = shift;
        
        delete $data{ refaddr $self };
        
        return;
    }
}

1;

package main;

use strict;
use warnings;

my $obj = new InOutObj;

$obj->set('i LiKe WiNe');

# User should not be able to make up stuff on their own!
print $obj->get()->{uPper} . "\n";

print "Why am I here?\n";