Method fill

src/prevector.h:200–211

    const T* item_ptr(difference_type pos) const { return is_direct() ? direct_ptr(pos) : indirect_ptr(pos); }

    void fill(T* dst, ptrdiff_t count) {
        if (IS_TRIVIALLY_CONSTRUCTIBLE<T>::value) {
            // The most common use of prevector is where T=unsigned char. For
            // trivially constructible types, we can use memset() to avoid
            // looping.
            ::memset(dst, 0, count * sizeof(T));
        } else {
            for (auto i = 0; i < count; ++i) {
                new(static_cast<void*>(dst + i)) T();
            }
        }
    }

    void fill(T* dst, ptrdiff_t count, const T& value) {
        for (auto i = 0; i < count; ++i) {