Template specializations with identical functions except for template parameter - c++

Question

How to take care of the repetitions below for the Object::func() definitions without using macros?
template <int N> struct Object {};
template <> struct Object<0> {
// special stuff
void func();
};
template <> struct Object<1> {
// special stuff
void func();
};
template <> struct Object<2> {
// special stuff
void func();
};
template <int N> struct Thing {};
void Object<0>::func() {
Thing<0> a;
// do stuff with a
}
void Object<1>::func() {
Thing<1> a;
// do exact same stuff with a
}
void Object<2>::func() {
Thing<2> a;
// do exact same stuff with a
}
Private inheritance, with the base having template int N? Meta-template stuff? CRTP? I can't figure it out. Note that
// special stuff
means that the template specializations are necessary--I'm just not showing how they are specialized. I'm only showing the one function func() that are almost identical to all of them.

Answer 1

Using inheritance you can avoid specialization for the common code. How about:
template <int N> struct ObjectBase {
void func();
};
template <int N> struct Thing {};
template <int N>
void ObjectBase<N>::func() {
Thing<N> a;
// do stuff with a
}
template <> struct Object<0>: private ObjectBase<0> {
// special stuff
};
template <> struct Object<1>: private ObjectBase<1> {
// special stuff
};
template <> struct Object<2>: private ObjectBase<2> {
// special stuff
};

Answer 2

For your question, my solution is to use template template parameters to define your template class, I feel this is the way to avoid re-define common things over and over.
Below is the code that I just coded and tested in Visual Studio 2013:
#include <iostream>
template <int N> struct Thing { int x; Thing() : x(N) {}; };
template <int N, template<int N> class T> struct Object { void func(); };
template <int N, template<int N> class T> void Object<N, T>::func()
{
T<N> a;
std::cout << a.x << std::endl;
};
int main()
{
Object<0, Thing> obj0;
Object<11, Thing> obj11;
Object<22, Thing> obj22;
obj0.func();
obj11.func();
obj22.func();
return 0;
}
This code will print:
0
11
22