指向模板化虚拟基类的指针的问题

问：

定义接口的常规方法使用虚拟基类，例如：

class BaseClass_B
{
public:
    BaseClass_B() {}
    virtual ~BaseClass_B() {}
    virtual void method(const int &fParam) const = 0;
};

template <class tDerivedClassParam>
class DerivedClass_B : public BaseClass_B
{
    void method(const int &fParam) const override final
    {
        // Do something useful
    }

};

class FinalClass_B
{
public:
    using TypeAlias = int;
};

然后，我可以创建一个派生对象，并将其地址分配给派生对象指针和基指针：

DerivedClass_B<FinalClass_B> object_B;
DerivedClass_B<FinalClass_B> *ptr_B;
BaseClass_B *basePtr_B;

ptr_B = &object_B;
basePtr_B = &object_B;

但是，当我尝试做同样的事情时，有一个模板化的虚拟基类：

template <class tBaseClassParam>
class BaseClass_A
{
public:
    BaseClass_A() {}
    virtual ~BaseClass_A() {}
    virtual void method(const int &fParam) const = 0;
};

//
// Note that BaseClass_A<> is defined using a type alias from FinalClass_A
//
template <class tDerivedClassParam>
class DerivedClass_A : public BaseClass_A<typename tDerivedClassParam::TypeAlias>
{
    void method(const int &fParam) const override final
    {
        // Doe something useful
    }
};

class FinalClass_A
{
public:
    using TypeAlias = int;
};

尝试时，我在最后一行出现错误：

DerivedClass_A<FinalClass_A> object_A;
DerivedClass_A<FinalClass_A> *ptr_A;
BaseClass_A<FinalClass_A> *basePtr_A;

ptr_A = &object_A;
basePtr_A = &object_A;  //<-- Generates error

我得到的编译器错误是：

error: cannot convert ‘DerivedClass_A<FinalClass_A>*’ to ‘BaseClass_A<FinalClass_A>*’ in assignment

我错过了什么???

顺便说一句，我在 C++14 上。