Getting name of class type by specialization of class template

Asked Jul 23 '19 at 11:19

Active Jul 23 '19 at 12:56

Viewed 48 times

I am trying to set variable name of template class A by it's definition.

I was inspired by this answer. My current files looks like this:

Header file

namespace N {
    // Definition of class A
    template <class T> class A {
    public:
         A();

         static const char* name;
    }

/*1*/ #define REGISTER_TYPE(T) template <> class N::A<T>::name = #T;
}

Source file

namespace N {
    template<class T>
    A<T>::A() 
    {
        //empty constructor
    }
}
REGISTER_TYPE(N::MyOtherClass);

But somehow, error messages 'name' in 'class N::A<N::MyOtherClass>' does not name a type and expected unqualified-id before '=' token (line with /*1*/) pops up, but variable with this name exists.

I am using C++17. I have already tried to

Where am I doing mistake?

Thanks for your help!

//EDIT:

Solved in comments. Result is:

#define REGISTER_TYPE(T) template <> const char * N::A<T>::name = #T;

edited Jul 23 '19 at 12:56

asked Jul 23 '19 at 11:19

Brykyz

forgotten some `:`? I mean: `class N::A::name` instead of `class N:A::name`? – max66 Jul 23 '19 at 11:23
You must use the actual type of `name` when defining it. It's not a `class`. – Some programmer dude Jul 23 '19 at 11:24
@max66 Thanks, my mistake, fixed – Brykyz Jul 23 '19 at 11:26
@Brykyz - `REGISTER_TYPE` is the same as `REGISTER_FILTER`? – max66 Jul 23 '19 at 11:27
@max66 Yes, it is – Brykyz Jul 23 '19 at 11:28
@Someprogrammerdude Does that mean that 'name' is supposed to be class? If that's case, how can I assign #T to variable name? – Brykyz Jul 23 '19 at 11:30
@Brykyz - As you can see, you've corrected two times your code. Code that is incomplete. How can we try to respond to your question if you don't show us an **exact** and complete, but minimal, code that reproduce the problem? – max66 Jul 23 '19 at 11:30
Have you ever used `static` member variables before? If so how did you define them in the source files? Using `class` or using the actual type of the variable? – Some programmer dude Jul 23 '19 at 11:36
@Someprogrammerdude So if I understand, instead of `template <> class N::A::name = #T` I should use `template <> const char* N::A::name = #T`, right? – Brykyz Jul 23 '19 at 11:57
Yes that's correct. – Some programmer dude Jul 23 '19 at 12:04
@Someprogrammerdude Ok, it's working, thanks for your help! – Brykyz Jul 23 '19 at 12:06

Getting name of class type by specialization of class template

0 Answers0