package Base;

sub new {
   my $package = shift;
   my $id = shift;

   return bless {
      id => $id,
   }, $package;
}

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

   $self->{id} = $id if defined $id;
   return $self->{id};
}

1;

package NameDecorator;

sub new {
   my $package = shift;
   my $base_or_decorated = shift;
   
   my $self = $base_or_decorated->new(@_);
   $self->{name} = undef;

   return $self->{name};
}

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

   $self->{name} = $name if defined $name;
   return $self->{name};
}

1;

...do the same for an AgeDecorator