Passer un objet par référence en C++

Question

Avant que les gens commencent à me dire de faire une recherche google pour mon problème, laissez-moi vous dire que j'ai essayé pendant un certain temps.

Je n'arrive pas à comprendre comment passer un objet par référence en C++, je continue d'obtenir une impression massive des erreurs du compilateur. Je peux les inclure s'ils pourraient aider. Plus précisément, j'essaie de transmettre le flux d'objet RSSFeed en référence à la fonction parseFeed dans un thread.

void parseFeed(RSSFeed& feed) { 
    //dostuff 
} 

RSSFeed feed(); 
thread(parseFeed, feed); // line 119 

erreurs:

g++ -g -Wall -pedantic -O0 -std=c++0x -D_GLIBCXX_USE_NANOSLEEP -D_GLIBCXX_USE_SCHED_YIELD -I/usr/class/cs110/include/libxml2 -I/usr/class/cs110/local/include -c -o news-aggregator.o news-aggregator.cc 
In file included from /usr/include/c++/4.6/functional:56:0, 
       from /usr/include/c++/4.6/bits/stl_algo.h:68, 
       from /usr/include/c++/4.6/algorithm:63, 
       from news-aggregator.cc:14: 
rss-feed.h: In constructor âconstexpr std::_Head_base<_Idx, _Head, false>::_Head_base(const _Head&) [with long unsigned int _Idx = 0ul, _Head = RSSFeed]â: 
/usr/include/c++/4.6/tuple:162:44: instantiated from âconstexpr std::_Tuple_impl<_Idx, _Head, _Tail ...>::_Tuple_impl(const _Head&, const _Tail& ...) [with long unsigned int _Idx = 0ul, _Head = RSSFeed, _Tail = {}]â 
/usr/include/c++/4.6/tuple:423:24: instantiated from âconstexpr std::tuple<_T1>::tuple(const _T1&) [with _T1 = RSSFeed]â 
/usr/include/c++/4.6/functional:1362:70: instantiated from âstd::_Bind_result<_Result, _Functor(_Bound_args ...)>::_Bind_result(_Functor&&, _Args&& ...) [with _Args = {RSSFeed&}, _Result = void, _Functor = void (*)(RSSFeed&), _Bound_args = {RSSFeed}]â 
/usr/include/c++/4.6/functional:1477:41: instantiated from âtypename std::_Bindres_helper<_Result, _Functor, _ArgTypes>::type std::bind(_Functor&&, _ArgTypes&& ...) [with _Result = void, _Functor = void (&)(RSSFeed&), _ArgTypes = {RSSFeed&}, typename std::_Bindres_helper<_Result, _Functor, _ArgTypes>::type = std::_Bind_result<void, void (*(RSSFeed))(RSSFeed&)>]â 
/usr/include/c++/4.6/thread:135:9: instantiated from âstd::thread::thread(_Callable&&, _Args&& ...) [with _Callable = void (&)(RSSFeed&), _Args = {RSSFeed&}]â 
news-aggregator.cc:119:25: instantiated from here 
rss-feed.h:54:3: error: âRSSFeed::RSSFeed(const RSSFeed&)â is private 
/usr/include/c++/4.6/tuple:97:25: error: within this context 
/usr/include/c++/4.6/tuple:97:25: error: use of deleted function âRSSFeed::RSSFeed(const RSSFeed&)â 
rss-feed.h:54:3: error: declared here 
rss-feed.h: In constructor âstd::_Head_base<_Idx, _Head, false>::_Head_base(_UHead&&) [with _UHead = RSSFeed, long unsigned int _Idx = 0ul, _Head = RSSFeed]â: 
/usr/include/c++/4.6/tuple:174:43: instantiated from âstd::_Tuple_impl<_Idx, _Head, _Tail ...>::_Tuple_impl(std::_Tuple_impl<_Idx, _Head, _Tail ...>&&) [with long unsigned int _Idx = 0ul, _Head = RSSFeed, _Tail = {}, std::_Tuple_impl<_Idx, _Head, _Tail ...> = std::_Tuple_impl<0ul, RSSFeed>]â 
/usr/include/c++/4.6/tuple:434:51: instantiated from âstd::tuple<_T1>::tuple(std::tuple<_T1>&&) [with _T1 = RSSFeed, std::tuple<_T1> = std::tuple<RSSFeed>]â 
/usr/include/c++/4.6/functional:1368:78: instantiated from âstd::_Bind_result<_Result, _Functor(_Bound_args ...)>::_Bind_result(std::_Bind_result<_Result, _Functor(_Bound_args ...)>&&) [with _Result = void, _Functor = void (*)(RSSFeed&), _Bound_args = {RSSFeed}, std::_Bind_result<_Result, _Functor(_Bound_args ...)> = std::_Bind_result<void, void (*(RSSFeed))(RSSFeed&)>]â 
/usr/include/c++/4.6/functional:1477:41: instantiated from âtypename std::_Bindres_helper<_Result, _Functor, _ArgTypes>::type std::bind(_Functor&&, _ArgTypes&& ...) [with _Result = void, _Functor = void (&)(RSSFeed&), _ArgTypes = {RSSFeed&}, typename std::_Bindres_helper<_Result, _Functor, _ArgTypes>::type = std::_Bind_result<void, void (*(RSSFeed))(RSSFeed&)>]â 
/usr/include/c++/4.6/thread:135:9: instantiated from âstd::thread::thread(_Callable&&, _Args&& ...) [with _Callable = void (&)(RSSFeed&), _Args = {RSSFeed&}]â 
news-aggregator.cc:119:25: instantiated from here 
rss-feed.h:54:3: error: âRSSFeed::RSSFeed(const RSSFeed&)â is private 
/usr/include/c++/4.6/tuple:101:42: error: within this context 
/usr/include/c++/4.6/tuple:101:42: error: use of deleted function âRSSFeed::RSSFeed(const RSSFeed&)â 
rss-feed.h:54:3: error: declared here 

résolu: fil (parseFeed, ref ( alimentation )); // ligne 119

Answer 1

Cette

RSSFeed feed(); 

est une déclaration de fonction qui renvoie un objet de type RSSFeed et n'a pas de paramètres. Ce n'est pas une définition d'objet.

Ecrire à la place

RSSFeed feed; 

il semble également dans la liste des messages d'erreur qui classe RSSFeed n'a pas le constructeur de copie qui est définie comme il est supprimé.