Re: oop inheritance graph

On Jun 25, 6:25 am, "a" <a...@mail.com> wrote:


ce


In the first, you only have a single instance of A; both B and C
have the same instance as their base class. In the second, you
have two instances. In C++, you use virtual inheritance to
achieve the first, e.g.:

First:

    class A {} ;
    class B : public virtual A {} ;
    class C : public virtual A {} ;
    class D : public B, public C {} ;

Second:

    class A {} ;
    class B : public A {} ;
    class C : public A {} ;
    class D : public B, public C {} ;

Note the presence of the keyword "virtual" in the inheritance in
the first.

I'm not too sure what you mean by "naming conflict". In the
first, there is only one instance of each class, so there is no
ambituity when referring to a base class. In the second, in D
(or when using an object of type D), any direct reference to A
is ambiguous, since the compiler doesn't know which one; to
disabmiguate, first refer to B or C, e.g. B::A::... or C::A::...

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