The following has nice one-liners for assigning parameters during initialization and for destroying parameters during destruction. However, I could not come up with any nice way to implement the tedious set and get sub-routines -- what's a nice way to implement them?

package ThePackage;
use diagnostics;
use warnings;
use strict;
use Scalar::Util qw(refaddr);
use Carp;
$Carp::Verbose = 1;
{
  my ( %parameter_a_of,
       %p_b_of,
       %param_c_of,
       %parameter_d_of,
     ) = ();

  my %init_aid = ( paramater_a  =>  \%parameter_a_of,
                   p_b          =>  \%p_b_of,
                   paramater_c  =>  \%param_c_of,
                   paramater_d  =>  \%parameter_d_of,
                 );

  sub new
  {
     my($class, $parameter_a, %h) = @_;

     my $new_object = bless \do{my $anon_scalar}, $class;

     $paramter_a_of{refaddr $new_object } = $parameter_a;
     
     defined $h{$_} and ${$init_aid{$_}}{refaddr $new_object} = $h{$_}
                   for (keys %init_aid);

     return $new_object;
  }

  sub DESTROY
  {
     my ($self) = @_;

     delete ${$init_aid{$_}}{refaddr $self } for (keys %init_aid);

     return;
  }

  sub get_parameter_a { return $parameter_a_of{refaddr $_[0]} }
  sub get_p_b         { return $p_b_of        {refaddr $_[0]} }
  sub get_param_c     { return $param_c_of    {refaddr $_[0]} }
  sub get_parameter_d { return $parameter_d_of{refaddr $_[0]} }

  sub set_parameter_a{ $parameter_a_of{refaddr $_[0]} = $_[1]; return;
+ }
  sub set_p_b        { $p_b_of        {refaddr $_[0]} = $_[1]; return;
+ }
  sub set_param_c    { $param_c_of    {refaddr $_[0]} = $_[1]; return;
+ }
  sub set_parameter_d{ $parameter_d_of{refaddr $_[0]} = $_[1]; return;
+ }
}
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