Re: Explicit template instanciation, what is incorrect

On Feb 24, 7:30 pm, Leon Pollak <le...@plris.com> wrote:


.. But


You cannot have 2 bodies for the same function of the same template.
You would need to specialize the class template for Dir = 1 and Dir =
2 individually, in order to achieve that.

I tried making the member function Body() as a template but even that
would not work as specializing a member template without specializing
the class template is not allowed. Moreover, virtual member function
templates are not allowed.

Here is how you would specialize your class cNHI_Task:

class cChnlTask{};
class cNHI_DTS{};

template <int Index, int Prio, int Dir>
class cNHI_Task : public cChnlTask, cNHI_DTS {
public:
    virtual void Body()
    {
        std::cout << "Dir = " << Dir << std::endl;
    }
};

template <int Index, int Prio>
class cNHI_Task <Index,Prio,1> : public cChnlTask, cNHI_DTS {
public:
    virtual void Body()
    {
        std::cout << "Specialization : Dir = " << 1 << std::endl;
    }
};

template <int Index, int Prio>
class cNHI_Task <Index,Prio,2> : public cChnlTask, cNHI_DTS {
public:
    virtual void Body()
    {
        std::cout << "Specialization : Dir = " << 2 << std::endl;
    }
};

int main()
{
    cNHI_Task<0,0,1> obj_dir_1;
    cNHI_Task<0,0,2> obj_dir_2;
    cNHI_Task<0,0,3> obj_dir_3;
    obj_dir_1.Body();
    obj_dir_2.Body();
    obj_dir_3.Body();
}