#!/usr/bin/perl
use strict;
use warnings;

package plugin;
our @ISA;

sub SAVE {
  print "SAVE von plugin($_[0]->{val})\n";
}

sub set_isa
{
  my $self=shift;
  my $name=shift;
  @ISA=($name);
}
1;

package klasse;
our @ISA;
use Digest::MD5  qw(md5_hex);

sub new { return bless {val=>$_[1]}, $_[0]; }

sub SAVE { print "SAVE von klasse($_[0]->{val})\n"; }

sub LOAD { print "LOAD von klasse($_[0]->{val})\n"; }

sub use_plugin
{
  my $self=shift;
  my $name=shift;
  my $obj_unique='plugins::'.md5_hex($self);
  return eval('
    no strict;
    @'.$obj_unique.'::ISA=('.$name.','.__PACKAGE__.');
    bless($self,'.$obj_unique.');
  ');
}
1;

my $obj1=klasse->new('TEST1');
$obj1->SAVE; # <= das SAVE aus klasse
$obj1->LOAD; # <= das LOAD aus klasse
print "\n";
$obj1=$obj1->use_plugin('plugin');
$obj1->SAVE; # <= das SAVE aus plugin
$obj1->LOAD; # <= das LOAD aus klasse
print "\n###########\n\n";
my $obj2=klasse->new('TEST2');
$obj2->SAVE; # <= das SAVE aus klasse
$obj2->LOAD; # <= das LOAD aus klasse
print "\n";
$obj2=$obj2->use_plugin('plugin');
$obj2->SAVE; # <= das SAVE aus plugin
$obj2->LOAD; # <= das LOAD aus klasse