sub some_event {
	my $cpp_obj = shift; # It's an arbitrary time later.  We have no guaranty
	# the object is still around.
	return unless $cpp_obj; # I want this to work: if the underlying C++ object
	# is gone $cpp_obj should return undef in scalar context.

	# Do stuff that will blow up if $cpp_obj is gone.
	# ...
}

sub i_get_called_from_cpp_code {
	my ($cpp_obj, $time) = @_;
	my $event = sub { some_event($cpp_obj) };
	Scheduler::new_event($time + 10, $event);
}

##</code><code>##

package Whatever;

sub new { my $self = 0; bless \$self } # $self is Whatever=SCALAR(0x9742b30)
sub blah { my $self = shift; say $self }

package main;

my $a = Whatever->new;
my $b = $a;

# I want to kill $a such that $b is now also undef.  How?
$a->blah;
$$a = undef; # I really want to undefine ALL references to Whatever=SCALAR(0x9742b30)
$b->blah; # This should die.