numpunct_byname

template<class E>
    class numpunct_byname : public numpunct<E> {
public:
    explicit numpunct_byname(const char *s, size_t refs = 0);
protected:
    ~numpunct_byname();
    };

The template class describes an object that can serve as a locale facet of type numpunct<E>. Its behavior is determined by the named locale s. The constructor initializes its base object with numpunct<E>(refs).