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perl/Examples/Chap9/Node.pm

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+
+
+###
+### Node.pm
+###
+
+## Chapter 9 section 2.1
+
+package Node;
+my %NAMES;
+sub new {
+  my ($class, $base_name, $behavior, $wiring) = @_;
+  my $self = {N => $base_name . ++$NAMES{$base_name}, 
+              B => $behavior,
+              W => $wiring,
+             };
+  for my $wire (values %$wiring) {
+    $wire->attach($self);
+  }
+  bless $self => $class;
+}
+sub notify {
+  my $self = shift;
+  my %vals;
+  while (my ($name, $wire) = each %{$self->{W}}) {
+    $vals{$name} = $wire->value($self);
+  }
+  $self->{B}->($self, %vals);
+}
+sub name {
+  my $self = shift;
+  $self->{N}|| "$self";
+}
+
+sub wire { $_[0]{W}{$_[1]} }
+sub set_wire {
+  my ($self, $wire, $value) = @_;
+  my $wire = $self->wire($wire);
+  $wire->set($self, $value);
+}
+
+sub revoke_wire {
+  my ($self, $wire) = @_;
+  my $wire = $self->wire($wire);
+  $wire->revoke($self);
+}