How do you tell the compiler that a function is purely virtual and will be declared only in a sub-class ? i.e, There is not implementation for the function in the current class.

Can you explicitly declare a virtual class in C++ ? [Like the abstract class keyword in Java]

Are friends of base classes not friends of sub-classes ?

Pramod Subramanyan wrote:

> How do you tell the compiler that a function is purely virtual and will be declared only in a sub-class ? i.e, There is not implementation for the function in the current class.

class  VirtualBase
{
    public    :
        virtual int        PureVirtual    ()    = 0;
};

> Can you explicitly declare a virtual class in C++ ? [Like the abstract class keyword in Java]

There is all kinds of possibilities in C++. However, I do not know Java well enough to answer these questions.

Jan

class  ACLASS {
public:
    virtual int virtual_member()=0;
};

With i don't know witch version of SC or DM C++ sometime i had to create the function on the .CPP:

    int ACLASS::virtual_member() {
    }

Roland


Pramod Subramanyan a écrit :

> How do you tell the compiler that a function is purely virtual and will be declared only in a sub-class ? i.e, There is not implementation for the function in the current class.
>
> Can you explicitly declare a virtual class in C++ ? [Like the abstract class keyword in Java]
>
> Are friends of base classes not friends of sub-classes ?