sub foo {
    my $self = shift;
    $self->do_something(on_success => sub {
      do_stuff();
      $self->log("done stuff");
      do_more_stuff();
      $self->log("done more stuff");
    });

##</code><code>##

  use NoClose;

  sub foo {
      # Still a cycle, but now a more obvious one!
      $self->do_something(on_success => sub : capture('$self') {
      do_stuff();
      $self->log("done stuff");
      do_more_stuff();
      $self->log("done more stuff");
    });