Introduction to OOP

Chapter 17: The Polymorphic Variable :

Chapter Summary

A polymorphic Variable is a variable that can reference more than one type of object
Polymorphic variables derive their power from interaction with inheritance, overriding and substituion.
A common polymorphic variable is the implicit variable that maintains the reciever during the execution of a method
Downcasting is the undoing of a polymorphic assignment
Pure polymorphism occurs when a polymorphic variable is used as an argument.