Virtual Functions: C Example

In C, imagine that you somehow had a linked list of employees -- both managers and non-managers (this would already require ugly typecasting). How would you print them in C?

for (emp = employee_list; emp != NULL; emp = emp->next) {

if (TypeOf(emp) == TYPE_EMPLOYEE))

print_employee(emp);

else if (TypeOf(emp) == TYPE_MANAGER))

print_manager(emp);

else if (TypeOf(emp) == TYPE_SUMMER_STUDENT))

print_summer_student(emp);

else

printf(“Degenerate list! Invalid employee type!\n”);

}

This method is clumsy, ugly, bug-prone, and causes tooth decay.

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