package Foo::Bar;

use Scalar::Util qw(refaddr);

my %var;

sub get_var {
  my $self = shift;

  return $var{ refaddr( $self ) };
}

sub set_var {
  my $self  = shift;
  my $value = shift;

  $var{ refaddr( $self ) } = $value;
  return 1;
}

# Not completely sure that this is correct.
sub new {
  my $class = shift;

  return bless \my($anon_scalar), $class;
}