Don't Return a Reference to an Object That Isn't in Scope!
After C++ programmers learn to pass by reference, they have a tendency to go hog-wild. It is possible, however, to overdo it. Remember that a reference is always an alias that refers to some other object. If you pass a reference into or out of a function, be sure to ask yourself, “What is the object I'm aliasing, and will it still exist every time it's used?”
Listing 12.4 illustrates the danger of returning a reference to an object that no longer exists.
Listing 12.4. Returning a Reference to a Nonexistent Object
0: // Listing 12.4 1: // Returning a reference to an object 2: // which no longer exists 3: #include <iostream> 4: 5: class SimpleCat 6: { 7: public: 8: SimpleCat (int age, ... |
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