C++ Primer Plus

More Stringbad Problems: Assignment Operators

Not all the problems in Listing 12.3 can be blamed on the default copy constructor; you have to look at the default assignment operator, too. Just as ANSI C allows structure assignment, C++ allows class object assignment. It does so by automatically overloading an assignment operator for a class. This operator has the following prototype:

Class_name & Class_name::operator=(const Class_name &);

That is, it takes and returns a reference to an object of the class. For example, here’s the prototype for the StringBad class:

StringBad & StringBad::operator=(const StringBad &);

When an Assignment Operator Is Used and What It Does

An overloaded assignment operator is used when you assign one object to another ...