Forward declare typename in template parameter list

Question

I have a function with the following signature:

template<typename Container, auto First = 0, auto Last = Container::size()>
doSomething(const Container& containter){...}

Is there a way which will allow the reordering of the template parameters, so I would be able to call the function like this:

doSomething<3,5>(someContainer);

Rather than have to do this:

doSomething<decltype(someContainer), 3,5>(someContainer);

This wouldn't be an issue, if I could move someCountainer after Last, however the default value of Last is derived from Container. Is there a way to forward declare Container within the template parameter list, or any functionality that would actually allow me to avoid having to add decltype(...) every time?

Answer 1

One way is overloading:

template<auto First, auto Last, typename Container>
void doSomething(const Container& containter);

template<auto First, typename Container>
void doSomething(const Container& containter) {
    doSomething<First, Container::size()>(containter);
}

template<typename Container>
void doSomething(const Container& containter) {
    doSomething<0, Container::size()>(containter);
}