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int main () {
  Employee *coder = new Employee("Joe Smith");
  Employee *typist = new Employee("Bill Jones");
  Manager *designer = new Manager("Jane Doe", *typist);

  coder = designer;
  coder.print->print();
}

Now, the object designer is not sliced, and the output is:

Manager: Jane Doe
Assistant: Bill Jones

Alternatively, it is often safer to use a smart pointer, like std::auto_ptr, to hold the address of allocated memory. This is typically more robust than the use of raw pointers.

int main () {
  auto_ptr<Employee> coder( new Employee("Joe Smith") );
  auto_ptr<Employee> typist( new Employee("Bill Jones") );
  auto_ptr<Manager> designer( new Manager("Jane Doe", *typist) );

  coder = designer; // Smith deleted, Doe xferred
  coder->print();
  // everyone deleted
}

Alternatively, references may be used to refer to the various derived employee objects.

int main () {
  Employee coder("Joe Smith");
  Employee typist("Bill Jones");
  Manager designer("Jane Doe", typist);

  Employee &toPrint = designer;  // Jane remains entire
  toPrint.print();
}

The most effective way to avoid slicing of objects is to ensure, whenever possible, that polymorphic base classes are abstract.

class Employee {
public:
  Employee(string theName) : name(theName) {};
  virtual ~Employee();
  string getName() const {return name;}
  virtual void print() const = 0;
private:
  string name;
};

The presence of a pure virtual function in the Employee base class ensures that no objects of type Employee will exist, and slicing cannot occur.

Risk Assessment

Slicing results in information being lost, which could lead to a program not working properly and hence to a denial-of-service attack.

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