Answer the following questions true (T) or false (F)

Question

1. We can assign a base class object to a derived class variable.

2. Virtual functions allow old code to call new code.

Answer 1

1. False
Explanation: Where would the parts of the derived class object that are not in the base class variable go? Once this issue is raised, you should realize this false by now, although this is not formally discussed until the next chapter. The difficulty is called the ‘slicing problem.”.
2. True
Explanation: Suppose the base class (already defined) called Figure. Figure has a draw member function declared with the virtual keyword and a member center. The center function, to do its job, calls erase, then calls draw to center the figure. In this case, a programmer can derive a class Triangle from the already defined (old) code for Figure. The derived class can have a different implementation (new code) of the virtual function draw, which will be called by the center member function. Thus old code calls new code.