Observations About Returning Objects

When a member function or standalone function returns an object, you have choices. The function could return a reference to an object, a constant reference to an object, an object, or a constant object. By now, you’ve seen examples of all but the last, so it’s a good time to review these options.

Returning a Reference to a const Object

The usual reason for using a const reference is efficiency, but there are restrictions on when this choice can be used. If a function returns an object that is passed to it, either by object invocation or as a method argument, you can increase the efficiency of the method by having it return a reference. For example, suppose you wanted to write a function Max() that returned the larger of two Vector objects, where Vector is the class developed in Chapter 11. The function would be used in this manner: