nsReadableFragment<CharT> fragment; const CharT* startPos = GetReadableFragment(fragment, kFirstFragment); return nsReadingIterator<CharT>(fragment, startPos, *this);
nsReadingIterator<CharT> result; return BeginReading(result);
basic_nsAReadableString<CharT>::BeginReading() const  {    nsReadableFragment<CharT> fragment;    const CharT* startPos = GetReadableFragment(fragment, kFirstFragment);    return nsReadingIterator<CharT>(fragment, startPos, *this);  }