1package My::PingPong;
2
3sub new {
4  my $self = shift;
5  my $class = ref($self) || $self;
6  bless {_num=>shift} => $class;
7}
8
9sub next {
10  my $self = shift;
11  $self->{_num}++;
12}
13
14sub value {
15  my $self = shift;
16  $self->{_num};
17}
18
191;