return *(BeginReading()+=aIndex);
nsReadingIterator<CharT> iter; return *(BeginReading(iter).advance(PRInt32(aIndex)));
basic_nsAReadableString<CharT>::CharAt( PRUint32 aIndex ) const  {    NS_ASSERTION(aIndex<Length(), "|CharAt| out-of-range");    return *(BeginReading()+=aIndex);  }