"Peter Dimov" <pdimov@mmltd.net> wrote in message news:00f501c52404$bff4fca0$6501a8c0@pdimov...
Gennadiy Rozental wrote:
I believe this version is much less intuitive. optional<T> v is still value of type T which may or may not be present. Accordingly when we print it we print the value if it present or print nothing if it not.
This isn't very useful. The output cannot be read back, and when printing a sequence of optionals much of the information is lost.
1. This is not exactly true Output most probably will look like: a, , v, c, d, , Which should be enough to restore it back 2. Why should I bother at all? In my opinion "able to restore" is not primary concern for output operators. I know numerous cases where result of operator<< couldn't be read back. Serialization of optional<T> does need to care about that. Gennadiy