// V0 properties and method
 // Implementing abstract visit (accepting consumer)
 void AcceptingConsumer(ObjectClassConsumer consumer)
 {
     consumer.Consume(this);
 }
 // Abstract visit (accepting consumer)
 abstract void AcceptingConsumer(ObjectClassConsumer consumer);
 // Abstract visit (accepting consumer)
 void abstract AcceptingConsumer(ObjectClassConsumer consumer);
 // V0 properties and method
 // Implementing abstract visit (accepting consumer)
 void AcceptingConsumer(ObjectClassConsumer consumer)
 {
     consumer.Consume(this);
 }