C++类的静态数据成员上的多态性

多态性可以用于C++类的静态数据成员（又名"类变量"）吗？

更新：正如 b4hand 所述，多态方法必须在基类中声明。但在这种情况下这是不可能的，因为事先不知道用户将在 containerDerived 中创建什么方法。

编辑了这个例子，包括参考文献;谢谢你提醒我。

以下是我将静态基类型（numBase）初始化为派生类型（numDer）的尝试：

#include <iostream>
class numBase                   //numBase is in a library user can not edit
{
};
class numDer : public numBase   //user defined class is a kind of numBase
{
    private:
        int num;
    public:
        void printNum() { std::cout << " numDer=" << num; }
        void inc() { num++; }
};
class containerBase             //containerBase is in a library user can not edit
{
    protected:
        //static numDer& count; //this compiles, but count can not be initialized to other types
        static numBase& count;  //this causes error six lines down from here
};
class containerDerived : public containerBase //user defined class is a kind of containerBase
{
    public:
        void inc() { count.inc(); } //error: 'count' was not declared in this scope
        void printCount() { std::cout << " containerDerived"; count.printNum(); }
};
/************************ user program **********************/
//initilialize static variable
numDer number;              //number could be any user defined type derived from numBase
numDer& containerBase::count = number; //initialize count to a kind of numBase
int main()
{
    containerDerived container1;
    containerDerived container2;
    container1.printCount();
    container1.inc();
    container2.inc();
    container1.printCount();
}

谢谢。