What is Negative_size exception in Bjarne's book?

Question

2nd edition of A Tour of C++ of Bjarne's Stroustrup goes into templates in chapter 6.

This is the code on page 80 that I am uncertain about. There is a Negative_size exception but I haven't been able to find it with a google search and adding std:: to it gave me the error:

error: ‘Negative_size’ is not a member of ‘std’
   26 |         throw std::Negative_size{};

template <typename T>
class Vector
{
public:
    explicit Vector(int s);
    ~Vector()
    {
        delete[] elem;
    }

    T &operator[](int i);
    const T &operator[](int i) const; // for const Vectors
    int size() const
    {
        return sz;
    }

private:
    T *elem;
    int sz;
};

template <typename T>
Vector<T>::Vector(int s)
{

    if (s < 0)
    {
        throw std::Negative_size{}; // where the compilation error occurs
    }
}

I also didn't see it mentioned in the errata.

EDIT:

Responses to comments

• Chapter 6 is about templates.
• I have read the book from the first chapter and so I haven't skipped anything. I wouldn't have posted a question otherwise.
• I initially posted code to figure out what the error is but I am including the rest to reproduce the problem. I didn't want to include extra code that wasn't asking about the issue itself but this was requested.