c++ - Templated class specialization where template argument is a template

Question

I wondering if something similar to this is possible. Basically, I have a templated class that occasionally takes objects of templated classes. I would like to specialize it (or just a member function)for a specific templated class, but the 'generic' form of that class.

template<typename T, typename S>
class SomeRandomClass
{
    //put something here
};

template<typename T>
class MyTemplateClass
{
    void DoSomething(T & t) {
       //...something
    }
};

template<>
void MyTemplateClass< SomeRandomClass<???> >::DoSomething(SomeRandomClass<???> & t)
{
    //something specialized happens here
}

Replacing the question marks with appropriate types (double, etc) works, but I would like it to remain generic. I don't know what to put there, as any types wouldn't have been defined. I've looked around, and learned about template template parameters, and tried various combinations to no avail. Thanks for the help!

Answer 1

It's possible to specialize the class like this

template <>
template <typename T,typename S>
class MyTemplateClass <SomeRandomClass<T,S> >
{
    void DoSomething(SomeRandomClass<T,S>& t) { /* something */ }
};

It's not possible to specialize just the member method, because the specialization is on the class as a whole, and you have to define a new class. You can, however, do

template <>
template <typename T,typename S>
class MyTemplateClass <SomeRandomClass<T,S> >
{
    void DoSomething(SomeRandomClass<T,S>& t);
};

template <>
template <typename T,typename S>
void MyTemplateClass<SomeRandomClass<T,S> >::DoSomething(SomeRandomClass<T,S>& t)
{
    // something
}

to split up the declaration and definition.