Re: Solving the data inheritance problem

From:
"James Kanze" <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
6 Dec 2006 12:12:12 -0500
Message-ID:
<1165410873.809359.16080@16g2000cwy.googlegroups.com>
Ondra Holub wrote:

      [...]

class A
{
public:
     // constructors are implemented elsewhere - not important for this
example
     A();
     A(const A& src);
};

template<typename T>
class B: public A
{
public:
     B(): A() { }
     B(const T& data): A(src), data_(data) { }

     T& GetData() { return data_; }
     const T& GetData() const { return data_; }

     void SetData(const T& data)
     {
         data_ = data;
     }

private:
     T data_;
};


What's the point? What does deriving from B buy us here? (I
know that the original question was rather abstract, and thus
difficult to answer, but I can't think of any real use case
where the above would be a solution.)

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