vp2015·11 yıl önce·discussIn fact boost::optional examples use default constructor in this case - at least all examples I've seen, see http://www.boost.org/doc/libs/1_58_0/libs/optional/doc/html/...
vp2015·11 yıl önce·discussAre you sure about that?Both resources below say something opposite.http://bit.ly/1SEnJQe - see optional<T>::optional()and http://bit.ly/1lh7eyv - see default constructor(I'm just curious)Edit: I've tested it, you are wrong. Default constructor of optional doesn't call Student constructor (VS2015).