std::vector<char>::iterator begin_iter, end_iter; // ... o_iter.range(begin_iter, end_iter);
The output iterator defines a range() method that
takes two random access iterators, a beginning iterator and an ending
iterator to the same container, and serializes just the container
subset that's specified by this iterator range.
range() only works with random access iterators,
so its application is limited to std::vector
and std::basic_string.