package BasisKlasse;

use strict;
use warnings;

sub new{
  my ($class,%args) = @_;
  my $self = {};
  bless $self,$class;

  $self->{Name} = $args{name} || "testname";
  $self->{Birthday} = $args{birth} || "00.00.0000";

  return $self;
}

sub name{
  my ($self,$name) = @_;
  $self->{Name} = $name if(defined $name);
  return $self->{Name};
}

sub birth{
  my ($self,$birth) = @_;
  $self->{Birthday} = $birth if(defined $birth);
  return $self->{Birthday};
}

1;

package AbgeleiteteKlasse;

use strict;
use warnings;
use base qw(BasisKlasse);

sub new{
  my ($class,%args) = @_;
  my $self = $class->SUPER::new(%args);
  $self->{Position} = $args{position} || "Angestellter";
  return $self;
}

sub position{
   #... mach was
}

1;

#!/usr/bin/perl

use strict;
use warnings;
use lib qw(.);
use AbgeleiteteKlasse;

my $mitarbeiter = AbgeleiteteKlasse->new(name => 'Rainer', birth => '12.12.1947',position => 'Sachbearbeiter');

print "Name: ",$mitarbeiter->name(),"\n",
      "Geburtsdatum: ",$mitarbeiter->birth(),"\n";