C++ Daimond Problem

Zeeshan Riaz

What is the solution of the diamond problem of Inheriting Classes. A class is inheritting from 2 base classes and both the base classes have a function/method with the same name. From the object of the child class how we can call a function of the one base class.

Nelek

If the functions have the same name but they get different parameters... only the function that fits the parameters should be called. Function (int Par1, CString Par2); Function (double Par1, int Par2); is not possible to call both at once although they have the same name. If both functions get the same number and typ of parameters, in the same order... then let's wait to another explanation from the high level users and I will learn it as well ;)

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Rinu_Raj

Hope you are aware of run time polymorhism. Keep the same name function/method as virtual function in the base class. For the derived class object pointer allocate the corresponding base class (whose function needs to be invoked) then call the function resulting the corresponding base class get invoked. See below to make things clear

class A
{
public:
virtual void show(){cout<<"Class A invoked"};
}
class B
{
public:
virtual void show(){cout<<"Class B invoked"};
}
class C: public A, public B
{
}

main()
{
C* ptr = new A;
ptr->show(); // "Class A invoked" will be printed
C* ptr1 = new B;
ptr1->show(); // "Class B invoked" will be printed
}

Jijo Raj

Muhammad Zeeshan wrote:

A class is inheritting from 2 base classes and both the base classes have a function/method with the same name.

The class structure is as follows?

Base1       Base2
  \\           /
   \\         /
	    \\       /
     Derived

If this is the class structure, then its not a classic C++ diamond problem.

Muhammad Zeeshan wrote:

From the object of the child class how we can call a function of the one base class.

Just prefix the base class name before the call. See the code snippet.

Derived DerivedObject;
DerivedObject.**Base1::**CommonFunction();

// If its allocated as pointer.
Derived* pDerivedObject = new Derived;
pDerivedObject->**Base1::**CommonFunction();

Does this solve your problem? Or is it something else? Regards, Jijo.

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SandipG

Use virtual public for deriving classes.

ThatsAlok

scope resolution operator [::]

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