Re: Solving the data inheritance problem
Kaba wrote:
class A {
public:
A();
A(const A& src);
};
template<typename T>
class B: public A {
public:
B();
B(const T& data);
T& GetData();
const T& GetData() const;
void SetData(const T& data);
private:
T data_;
};
Yes, this is quite the thing I was after! If I just make the GetData()
functions virtual and part of A and fix T to some type, I get exactly
what I wanted.
Hm, what have you gained then?
class A {
public:
A();
A(const A&);
virtual T& GetData(); // or pure virtual?
private:
T data_;
};
class B[i] : public A {
...here you have to implement all functionality like swap, ...
};
Isn't that the case you wanted to get rid of?
I think using mixin classes offers another solution. A is now just a
/real/ interface with neither data nor implementation.
class A {
virtual T& GetData() = 0;
...
};
class B[i] : public A {
...all the things B[i] adds to A...
};
template <typename B>
class SharedCode : public B {
public:
SharedCode(const SharedCode&);
SharedCode& operator=(const SharedCode&);
T& GetData();
void swap(SharedCode&);
...
private:
T data_;
};
typedef SharedCode<B[0]> B[0]_leaf;
typedef SharedCode<B[1]> B[1]_leaf;
...
Ali
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