Passing in unspecialized class as a template parameter [duplicate]

Question

I have a class that looks like this:

template <typename T> struct myclass;
template <typename T> struct myclass {
  T value;
  vector< unique_ptr<myclass<T>> > children;
};

This works great, but what I'd really like is to be able to specify vector as a template parameter:

template <typename T, typename Container> struct myclass;
template <typename T, typename Container> struct myclass {
  T value;
  Container< unique_ptr<myclass<T>> > children;
}

myclass<int, vector> x;

I understand that this doesn't work, how do I do something like it where Container can be any vector-like class?

Answer 1

Sure, those are called template-templates. It's a mouthful of a name, but the syntax is roughly what you want it to be.

template <typename T, template <typename> typename Container>
struct MyClass {
  T value;
  Container< unique_ptr<MyClass<T, Container>> > children;
}

MyClass<int, std::vector> x;