# http://prometheus.frii.com/%7Egnat/yapc/2000-stages/slide47.html
# (Nathan Torkington on Opaque Objects)
  sub new {
    my $value = 0;
    bless sub {
      local $_ = shift;
      /get/ and return $value
	    or
      /set/ and $value = shift
	    or
      die "Unknown method: $_";
    }, shift;
  }
  sub get { +shift->("get", @_) }
  sub set { +shift->("set", @_) }