5

このスニペットの最後の行をプログラムコードに追加すると、次のようになります。

typedef std::set<Job> JobSet;
typedef boost::shared_ptr<JobSet> JobSetPtr;
JobSetPtr jobs_;

jobs_->insert ( job );  // line 60

このエラーが発生します:

    g++-4.7  -o /home/kron/Software/Synchronizer/1.0/Main.o -c src/Main.cpp
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h: In instantiation of ‘bool std::less<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = Job]’:
/usr/include/c++/4.7/bits/stl_tree.h:1285:4:   required from ‘std::pair<std::_Rb_tree_iterator<_Val>, bool> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_insert_unique(const _Val&) [with _Key = Job; _Val = Job; _KeyOfValue = std::_Identity<Job>; _Compare = std::less<Job>; _Alloc = std::allocator<Job>]’
/usr/include/c++/4.7/bits/stl_set.h:415:29:   required from ‘std::pair<typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::const_iterator, bool> std::set<_Key, _Compare, _Alloc>::insert(const value_type&) [with _Key = Job; _Compare = std::less<Job>; _Alloc = std::allocator<Job>; typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::const_iterator = std::_Rb_tree_const_iterator<Job>; std::set<_Key, _Compare, _Alloc>::value_type = Job]’
src/Configuration.hpp:60:27:   required from here
/usr/include/c++/4.7/bits/stl_function.h:236:22: error: no match for ‘operator<’ in ‘__x < __y’
/usr/include/c++/4.7/bits/stl_function.h:236:22: note: candidates are:
In file included from /usr/include/c++/4.7/bits/stl_algobase.h:65:0,
                 from /usr/include/c++/4.7/bits/char_traits.h:41,
                 from /usr/include/c++/4.7/ios:41,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_pair.h:218:5: note: template<class _T1, class _T2> bool std::operator<(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)
/usr/include/c++/4.7/bits/stl_pair.h:218:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::pair<_T1, _T2>’
In file included from /usr/include/c++/4.7/bits/stl_algobase.h:68:0,
                 from /usr/include/c++/4.7/bits/char_traits.h:41,
                 from /usr/include/c++/4.7/ios:41,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_iterator.h:299:5: note: template<class _Iterator> bool std::operator<(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)
/usr/include/c++/4.7/bits/stl_iterator.h:299:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::reverse_iterator<_Iterator>’
In file included from /usr/include/c++/4.7/bits/stl_algobase.h:68:0,
                 from /usr/include/c++/4.7/bits/char_traits.h:41,
                 from /usr/include/c++/4.7/ios:41,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_iterator.h:349:5: note: template<class _IteratorL, class _IteratorR> bool std::operator<(const std::reverse_iterator<_IteratorL>&, const std::reverse_iterator<_IteratorR>&)
/usr/include/c++/4.7/bits/stl_iterator.h:349:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::reverse_iterator<_IteratorL>’
In file included from /usr/include/c++/4.7/string:54:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/basic_string.h:2566:5: note: template<class _CharT, class _Traits, class _Alloc> bool std::operator<(const std::basic_string<_CharT, _Traits, _Alloc>&, const std::basic_string<_CharT, _Traits, _Alloc>&)
/usr/include/c++/4.7/bits/basic_string.h:2566:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::basic_string<_CharT, _Traits, _Alloc>’
In file included from /usr/include/c++/4.7/string:54:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/basic_string.h:2578:5: note: template<class _CharT, class _Traits, class _Alloc> bool std::operator<(const std::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)
/usr/include/c++/4.7/bits/basic_string.h:2578:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::basic_string<_CharT, _Traits, _Alloc>’
In file included from /usr/include/c++/4.7/string:54:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/basic_string.h:2590:5: note: template<class _CharT, class _Traits, class _Alloc> bool std::operator<(const _CharT*, const std::basic_string<_CharT, _Traits, _Alloc>&)
/usr/include/c++/4.7/bits/basic_string.h:2590:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   mismatched types ‘const _CharT*’ and ‘Job’
In file included from /usr/include/c++/4.7/vector:65:0,
                 from src/Main.cpp:2:
/usr/include/c++/4.7/bits/stl_vector.h:1372:5: note: template<class _Tp, class _Alloc> bool std::operator<(const std::vector<_Tp, _Alloc>&, const std::vector<_Tp, _Alloc>&)
/usr/include/c++/4.7/bits/stl_vector.h:1372:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::vector<_Tp, _Alloc>’
In file included from /usr/include/c++/4.7/set:60:0,
                 from src/Configuration.hpp:4,
                 from src/Main.cpp:5:
/usr/include/c++/4.7/bits/stl_tree.h:873:5: note: template<class _Key, class _Val, class _KeyOfValue, class _Compare, class _Alloc> bool std::operator<(const std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>&, const std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>&)
/usr/include/c++/4.7/bits/stl_tree.h:873:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>’
In file included from /usr/include/c++/4.7/set:61:0,
                 from src/Configuration.hpp:4,
                 from src/Main.cpp:5:
/usr/include/c++/4.7/bits/stl_set.h:721:5: note: template<class _Key, class _Compare, class _Alloc> bool std::operator<(const std::set<_Key, _Compare, _Alloc>&, const std::set<_Key, _Compare, _Alloc>&)
/usr/include/c++/4.7/bits/stl_set.h:721:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::set<_Key, _Compare, _Alloc>’
In file included from /usr/include/c++/4.7/set:62:0,
                 from src/Configuration.hpp:4,
                 from src/Main.cpp:5:
/usr/include/c++/4.7/bits/stl_multiset.h:702:5: note: template<class _Key, class _Compare, class _Alloc> bool std::operator<(const std::multiset<_Key, _Compare, _Alloc>&, const std::multiset<_Key, _Compare, _Alloc>&)
/usr/include/c++/4.7/bits/stl_multiset.h:702:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::multiset<_Key, _Compare, _Alloc>’
In file included from /usr/include/c++/4.7/list:64:0,
                 from /usr/include/boost/algorithm/string/std/list_traits.hpp:15,
                 from /usr/include/boost/algorithm/string/std_containers_traits.hpp:20,
                 from /usr/include/boost/algorithm/string.hpp:18,
                 from src/Configuration.hpp:9,
                 from src/Main.cpp:5:
/usr/include/c++/4.7/bits/stl_list.h:1659:5: note: template<class _Tp, class _Alloc> bool std::operator<(const std::list<_Tp, _Alloc>&, const std::list<_Tp, _Alloc>&)
/usr/include/c++/4.7/bits/stl_list.h:1659:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::list<_Tp, _Alloc>’
In file included from /usr/include/c++/4.7/deque:65:0,
                 from /usr/include/boost/algorithm/string/find_format.hpp:14,
                 from /usr/include/boost/algorithm/string/replace.hpp:22,
                 from /usr/include/boost/algorithm/string.hpp:25,
                 from src/Configuration.hpp:9,
                 from src/Main.cpp:5:
/usr/include/c++/4.7/bits/stl_deque.h:274:5: note: template<class _Tp, class _Ref, class _Ptr> bool std::operator<(const std::_Deque_iterator<_Tp, _Ref, _Ptr>&, const std::_Deque_iterator<_Tp, _Ref, _Ptr>&)
/usr/include/c++/4.7/bits/stl_deque.h:274:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::_Deque_iterator<_Tp, _Ref, _Ptr>’
In file included from /usr/include/c++/4.7/deque:65:0,
                 from /usr/include/boost/algorithm/string/find_format.hpp:14,
                 from /usr/include/boost/algorithm/string/replace.hpp:22,
                 from /usr/include/boost/algorithm/string.hpp:25,
                 from src/Configuration.hpp:9,
                 from src/Main.cpp:5:
/usr/include/c++/4.7/bits/stl_deque.h:282:5: note: template<class _Tp, class _RefL, class _PtrL, class _RefR, class _PtrR> bool std::operator<(const std::_Deque_iterator<_Tp, _RefL, _PtrL>&, const std::_Deque_iterator<_Tp, _RefR, _PtrR>&)
/usr/include/c++/4.7/bits/stl_deque.h:282:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::_Deque_iterator<_Tp, _RefL, _PtrL>’
In file included from /usr/include/c++/4.7/deque:65:0,
                 from /usr/include/boost/algorithm/string/find_format.hpp:14,
                 from /usr/include/boost/algorithm/string/replace.hpp:22,
                 from /usr/include/boost/algorithm/string.hpp:25,
                 from src/Configuration.hpp:9,
                 from src/Main.cpp:5:
/usr/include/c++/4.7/bits/stl_deque.h:1947:5: note: template<class _Tp, class _Alloc> bool std::operator<(const std::deque<_Tp, _Alloc>&, const std::deque<_Tp, _Alloc>&)
/usr/include/c++/4.7/bits/stl_deque.h:1947:5: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/4.7/string:50:0,
                 from /usr/include/c++/4.7/bits/locale_classes.h:42,
                 from /usr/include/c++/4.7/bits/ios_base.h:43,
                 from /usr/include/c++/4.7/ios:43,
                 from /usr/include/c++/4.7/ostream:40,
                 from /usr/include/c++/4.7/iostream:40,
                 from src/Main.cpp:1:
/usr/include/c++/4.7/bits/stl_function.h:236:22: note:   ‘const Job’ is not derived from ‘const std::deque<_Tp, _Alloc>’
make: *** [/home/kron/Software/Synchronizer/1.0/Main.o] Error 1

それは私のせいですか?はいの場合、私が間違ったことは何ですか?いいえの場合、誰かが同じエラーを抱えていますか?

4

2 に答える 2

10

<タイプの2つのオブジェクトを比較するための演算子の定義を提供していないようですJob

にオブジェクトを挿入する場合std::set、コンテナはアイテムを挿入する位置を認識する必要があります。そのため、コンテナは、挿入されるオブジェクトをセットにすでに存在するアイテムと比較する必要があります。<そのために、あなたが提供していないと思う演算子を使用します。std::set<Job>タイプの2つのオブジェクトを比較する方法がわからないだけですJob

だからあなたはクラスを提供operator<することができます。Job

Jobまたは、オブジェクトを比較するためにこのファンクターを定義します。

struct JobComparer
{
    bool operator()(Job const &j1, Job const &j2)
    {
        //compare j1 and j2 and return true or false
    }
};

次に、それを次のように使用します。

typedef std::set<Job, JobComparer> JobSet;

または、ここで説明するstd::lessように専門化することもできます。

あなたはこのトピックを見ることができました:

于 2012-04-14T17:14:12.433 に答える
6

ナワズは簡単な答えを提供しましたが、もっと完全な答えに値すると思います。

setC ++のオブジェクトのAは、重複のない順序付けられたコンテナーです。オブジェクトを並べ替えることができるように、オブジェクト自体以外の2番目のテンプレートパラメーターを使用します。2つのオブジェクトを比較することを目的とするファンクターです。また、メモリ割り当てに3番目のパラメータを使用しますが、ここでは役に立ちません。

を使用するset場合、次の2つのパラメーターを指定します。

struct NameComparator {
    template <typename T>
    bool operator()(T const& left, T const& right) {
        return left.name() < right.name();
    }
};

std::set<Job, NameComparator> JobSet;

提供されるコンパレータは、順序の概念を定義する必要があります。基本的に、<2つの整数に対してどのように機能するかを考えてください。

  • それは反射的ではありません:x < x決して成り立たない
  • それは反対称です:もしx < yそれy < xが偽なら
  • それは推移的です:if x < yand y < zthenx < z

これは非常に一般的な関係であるため、このようなファンクターは標準ライブラリに存在します。template <typename T> struct std::less;これは、任意のタイプTで機能し、指定された2つのインスタンスで演算子を使用できます<

そして、そのままでは、set明示的に指定しなかったの2番目のパラメーターはデフォルトで。になりstd::less<TypeOfObjectInSet>ます。つまり、<定義されているオブジェクトが提供されている場合は、箱から出してすぐに機能します。

したがって、3つのソリューションがあります。

オブジェクトが「自然な」順序関係を認めている場合は、を定義operator<または特殊化できますstd::less。それ以外の場合、このセットに何らかの順序関係が必要な場合は、独自のコンパレータを提供できます。

注文が不要な場合は、を使用できることに注意しくださいunordered_set。ハッシュと平等関係​​が必要です。

于 2012-04-14T17:43:40.167 に答える