Thread: Specialising a member function with a template template parameter

Here is the guts of my problem...

I dont seem to be able to use the template template parameters TT1, TT2 & TT3 to specialize my member function Container:: object(). Basically I want to use them in order to select the
correct member variable index1_, index2_ and index3_ as this presents a nice Tag-style interface.

Any Ideas?

Code:

template<class T> struct X{ /* omitted*/ };
template<class T> struct Y{ /* omitted*/ };
template<class T> struct Z{ /* omitted*/ };

template < class T,
template <typename> class TT1,
template <typename> class TT2,
template <typename> class TT3>
struct Container
{
 template <template <typename> class FTT> FTT<T> object();

 /* All functions fail to compile. Error is
 // error C3207: 'MyClass<T,TT1,TT2,TT3>:: object' :
 // invalid template argument for 'FTT', class template expected
 template <> TT1<T> object<TT1>() { return object1_;}
 template <> TT2<T> object<TT12>() { return object2_;}
 template <> TT3<T> object<TT13() { return object3_;}
 //*/

 //* Compiles but needs to use template template parameters for generality
 template <> X<T> object<X>() { return object1_;}
 template <> Y<T> object<Y>() { return object2_;}
 template <> Z<T> object<Z>() { return object3_;}
 //*/

 private:

 TT1<T> object1_;
 TT2<T> object2_;
 TT3<T> object3_;
};


int _tmain(int argc, _TCHAR* argv[])
{
 Container<int, X, Y, Z> container;
 X<int> result1 = container.object<X>();
 Y<int> result2 = container.object<Y>();
 Z<int> result3 = container.object<Z>();
 return 0;
}