package My::Class::_Implementation;

sub _add
{
    my $me= shift @_;
    # ...
}

sub _init
{
    my $me= shift @_;
    # ...
}

*My::Class::instancePackage= sub {
    my $class= shift @_;
    return $class . "::Object";
};

*My::Class::new= sub {
    my $us= shift @_;
    my $me= bless {}, $us->instancePackage();
    _init( $me );
    return $me;
};

*My::Class::Object::new= sub {
    my $me= shift @_;
    my $new= bless {}, ref($me);
    _init( $me );
    return $me;
};

*My::Class::Object::method= sub {
    my $me= shift @_;
    _add( $me, @_ );
};