Suppose the following case (Dreaded Diamond):
EXAMPLE
class Base //It's the Base class
{
//...
Base& operator=(const Base&); //Copy construct
//...
};
class Derived1:virtual public Base
{
//...
Derived1& operator=(const Derived1&);
//...
}
class Derived2:virtual public Base
{
//...
Derived2& operator=(const Derived2&);
//...
}
class Derived12:public Derived1, public Derived2
{
//...
Derived12& operator=(const Derived12&);
//...
}
Example:
//...
Base* object1 = new Derived12;
Base* object2 = new Derived12;
*object1 = *object2; //this line
//...
PROBLEM
When "this line" is performed, the "operator=" function, from Base, is called.
Yet the result I seek is not this. I would like the assignment operator applied to be the one specified in Derived12 class. I understand that overloading "operator=" function is impossible, because the signature of each function would differ from class to class.
QUESTION
- Is there any way to make the compiler understand what is the assignment function I want to be applied ?
- If it's not possible with operator overloading, can you suggest some other way?
Thank you, in advance, for any suggestion.
UPDATE:
First, about the Suggested Question Similar To Mine. It does not answer my question. There I understood that in case I have an assignment of derived class object to base class object, the operator= in base class may just fill it's "untouched", during assignment, members with some default values.
Here I asked whether it's possible to make the compiler see -- that's the derived class I'm referring to and not the base. I would like to, somehow, make the assignment work with derived class members and not with the base ones.
I think I should explain the purpose of my question.
I have a similar problem I want to solve. Speaking in terms of the example above: I want to create an array of pointers to objects of mixed types: Derived, Derived1, Derived12 (each time a new object is created, the program checks if it's already present in array: if yes - new object isn't added, if no - the new object is assigned to the next uninitialized object in array.) I thought that using an array of pointers to base class would be the solution, but then encountered this problem. May be it's not the best method.
