anahtarında bir std :: unordered_map anahtar olarak bir std :: çifti oluşturmaya çalışıyorum. Tahmin edebileceğiniz gibi, bu, anahtarlar için bir eşitlik karşılaştırıcısının yanı sıra, belirli bir anahtar için bir karma oluşturmak için bir sınıfın açıkça belirtilmesini gerektirecektir. İşte benim kod şimdiye kadar var:std :: unordered_map bir std :: çifti ile
#include <unordered_map>
#include <memory>
#include <utility>
template <class T, typename U>
struct PairHash{
size_t operator()(const std::pair<T, U> &key){
return std::hash<T>()(key.first)^std::hash<U>()(key.second);
}
};
template <class T, typename U>
struct PairEqual{
bool operator()(const std::pair<T, U> &lhs, const std::pair<T, U> &rhs) const{
return lhs.first == rhs.first && lhs.second == rhs.second;
}
};
struct GraphEdge{
};
int main(){
std::unordered_map<std::pair<int, int>,
std::unique_ptr<GraphEdge>,
PairHash<int, int>,
PairEqual<int, int>> edges;
}
Ancak bu bana oldukça (Gözlerime en az) esrarengiz derleyici hata verir:
In file included from /usr/include/c++/5/bits/hashtable.h:35:0,
from /usr/include/c++/5/unordered_map:47,
from prog.cpp:1:
/usr/include/c++/5/bits/hashtable_policy.h: In instantiation of 'struct std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> >':
/usr/include/c++/5/type_traits:137:12: required from 'struct std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > >'
/usr/include/c++/5/type_traits:148:38: required from 'struct std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
/usr/include/c++/5/bits/unordered_map.h:100:66: required from 'class std::unordered_map<std::pair<int, int>, std::unique_ptr<GraphEdge>, PairHash<int, int>, PairEqual<int, int> >'
prog.cpp:29:43: required from here
/usr/include/c++/5/bits/hashtable_policy.h:85:34: error: no match for call to '(const PairHash<int, int>) (const std::pair<int, int>&)'
noexcept(declval<const _Hash&>()(declval<const _Key&>()))>
^
prog.cpp:7:12: note: candidate: size_t PairHash<T, U>::operator()(const std::pair<_T1, _T2>&) [with T = int; U = int; size_t = unsigned int] <near match>
size_t operator()(const std::pair<T, U> &key){
^
prog.cpp:7:12: note: passing 'const PairHash<int, int>*' as 'this' argument discards qualifiers
In file included from /usr/include/c++/5/bits/move.h:57:0,
from /usr/include/c++/5/bits/stl_pair.h:59,
from /usr/include/c++/5/utility:70,
from /usr/include/c++/5/unordered_map:38,
from prog.cpp:1:
/usr/include/c++/5/type_traits: In instantiation of 'struct std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >':
/usr/include/c++/5/bits/unordered_map.h:100:66: required from 'class std::unordered_map<std::pair<int, int>, std::unique_ptr<GraphEdge>, PairHash<int, int>, PairEqual<int, int> >'
prog.cpp:29:43: required from here
/usr/include/c++/5/type_traits:148:38: error: 'value' is not a member of 'std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > >'
: public integral_constant<bool, !_Pp::value>
^
In file included from /usr/include/c++/5/unordered_map:48:0,
from prog.cpp:1:
/usr/include/c++/5/bits/unordered_map.h: In instantiation of 'class std::unordered_map<std::pair<int, int>, std::unique_ptr<GraphEdge>, PairHash<int, int>, PairEqual<int, int> >':
prog.cpp:29:43: required from here
/usr/include/c++/5/bits/unordered_map.h:100:66: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef __umap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable;
^
/usr/include/c++/5/bits/unordered_map.h:107:45: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::key_type key_type;
^
/usr/include/c++/5/bits/unordered_map.h:108:47: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::value_type value_type;
^
/usr/include/c++/5/bits/unordered_map.h:109:48: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::mapped_type mapped_type;
^
/usr/include/c++/5/bits/unordered_map.h:110:43: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::hasher hasher;
^
/usr/include/c++/5/bits/unordered_map.h:111:46: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::key_equal key_equal;
^
/usr/include/c++/5/bits/unordered_map.h:112:51: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::allocator_type allocator_type;
^
/usr/include/c++/5/bits/unordered_map.h:117:45: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::pointer pointer;
^
/usr/include/c++/5/bits/unordered_map.h:118:50: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::const_pointer const_pointer;
^
/usr/include/c++/5/bits/unordered_map.h:119:47: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::reference reference;
^
/usr/include/c++/5/bits/unordered_map.h:120:52: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::const_reference const_reference;
^
/usr/include/c++/5/bits/unordered_map.h:121:46: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::iterator iterator;
^
/usr/include/c++/5/bits/unordered_map.h:122:51: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::const_iterator const_iterator;
^
/usr/include/c++/5/bits/unordered_map.h:123:51: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::local_iterator local_iterator;
^
/usr/include/c++/5/bits/unordered_map.h:124:57: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::const_local_iterator const_local_iterator;
^
/usr/include/c++/5/bits/unordered_map.h:125:47: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::size_type size_type;
^
/usr/include/c++/5/bits/unordered_map.h:126:52: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
typedef typename _Hashtable::difference_type difference_type;
^
/usr/include/c++/5/bits/unordered_map.h:280:7: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
operator=(initializer_list<value_type> __l)
^
/usr/include/c++/5/bits/unordered_map.h:379:2: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
emplace(_Args&&... __args)
^
/usr/include/c++/5/bits/unordered_map.h:432:7: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
insert(const value_type& __x)
^
/usr/include/c++/5/bits/unordered_map.h:439:2: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
insert(_Pair&& __x)
^
/usr/include/c++/5/bits/unordered_map.h:499:7: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
insert(initializer_list<value_type> __l)
^
/usr/include/c++/5/bits/unordered_map.h:645:7: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
equal_range(const key_type& __x)
^
/usr/include/c++/5/bits/unordered_map.h:649:7: error: 'value' is not a member of 'std::__not_<std::__and_<std::__is_fast_hash<PairHash<int, int> >, std::__detail::__is_noexcept_hash<std::pair<int, int>, PairHash<int, int> > > >'
equal_range(const key_type& __x) const
^
yanlış yapıyorum?
Bir yan notda, stl içeren derleyici hataları çözmek çok sıkıcı. Hataların ne olduğunu, geri kalanların isimleri iç içe geçtiğini anlamak için bir günlük okumalısınız. Intellisense'de bir prototip okumaya çalıştığınızda aynı problem. Bu sinir bozucu. –
Kodunuz VS2015 ile benim için derler. –