Deferred Methods

Part of what makes a framework work is the concept of a deferred method. A deferred method is a generalization of overriding. The parent class names the method, but provides no implementation. Instead, the child class must provide an implementation, and give meaning to the operation. Thus, the parent class is a specification, the child class an implementation.

[audio] [real] Text to accompany slide17, in Chapter 14 of An Introduction to Object-Oriented Programming