高阶函数&xAB；过滤器&xBB；在C++； 我想用C++编写一个高阶函数过滤器< /C>。到目前为止，我提出的代码如下： #include <iostream> #include <string> #include <functional> #include <algorithm> #include <vector> #include <list> #include <iterator> using namespace std; bool isOdd(int const i) { return i % 2 != 0; } template < template <class, class> class Container, class Predicate, class Allocator, class A > Container<A, Allocator> filter(Container<A, Allocator> const & container, Predicate const & pred) { Container<A, Allocator> filtered(container); container.erase(remove_if(filtered.begin(), filtered.end(), pred), filtered.end()); return filtered; } int main() { int const a[] = {23, 12, 78, 21, 97, 64}; vector<int const> const v(a, a + 6); vector<int const> const filtered = filter(v, isOdd); copy(filtered.begin(), filtered.end(), ostream_iterator<int const>(cout, " ")); } #包括 #包括 #包括 #包括 #包括 #包括 #包括 使用名称空间std； 布尔isOdd（内部常数i）{ 返回i%2！=0； } 模板< 模板类容器， 类谓词， 类分配器， 甲级 > 容器过滤器（容器常量和容器、谓词常量和pred）{ 容器过滤（容器）； container.erase（如果（filtered.begin（）、filtered.end（）、pred）、filtered.end（）删除_）； 返回过滤； } int main（）{ int const a[]={23,12,78,21,97,64}； 向量常数v（a，a+6）； 向量常数过滤=过滤器（v，isOdd）； 复制（filtered.begin（）、filtered.end（）、ostream_迭代器（cout，“”）； }

然而，在编译这段代码时，我得到了以下我无法理解的错误消息，并因此消除了这些错误消息：

/usr/include/c++/4.3/ext/new_allocator.h: In instantiation of ‘__gnu_cxx::new_allocator<const int>’:
/usr/include/c++/4.3/bits/allocator.h:84:   instantiated from ‘std::allocator<const int>’
/usr/include/c++/4.3/bits/stl_vector.h:75:   instantiated from ‘std::_Vector_base<const int, std::allocator<const int> >’
/usr/include/c++/4.3/bits/stl_vector.h:176:   instantiated from ‘std::vector<const int, std::allocator<const int> >’
Filter.cpp:29:   instantiated from here
/usr/include/c++/4.3/ext/new_allocator.h:82: error: ‘const _Tp* __gnu_cxx::new_allocator<_Tp>::address(const _Tp&) const [with _Tp = const int]’ cannot be overloaded
/usr/include/c++/4.3/ext/new_allocator.h:79: error: with ‘_Tp* __gnu_cxx::new_allocator<_Tp>::address(_Tp&) const [with _Tp = const int]’
Filter.cpp: In function ‘Container<A, Allocator> filter(const Container<A, Allocator>&, const Predicate&) [with Container = std::vector, Predicate = bool ()(int), Allocator = std::allocator<const int>, A = const int]’:
Filter.cpp:30:   instantiated from here
Filter.cpp:23: error: passing ‘const std::vector<const int, std::allocator<const int> >’ as ‘this’ argument of ‘__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> > std::vector<_Tp, _Alloc>::erase(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, __gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >) [with _Tp = const int, _Alloc = std::allocator<const int>]’ discards qualifiers
/usr/include/c++/4.3/bits/stl_algo.h: In function ‘_FIter std::remove_if(_FIter, _FIter, _Predicate) [with _FIter = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >, _Predicate = bool (*)(int)]’:
Filter.cpp:23:   instantiated from ‘Container<A, Allocator> filter(const Container<A, Allocator>&, const Predicate&) [with Container = std::vector, Predicate = bool ()(int), Allocator = std::allocator<const int>, A = const int]’
Filter.cpp:30:   instantiated from here
/usr/include/c++/4.3/bits/stl_algo.h:821: error: assignment of read-only location ‘__result.__gnu_cxx::__normal_iterator<_Iterator, _Container>::operator* [with _Iterator = const int*, _Container = std::vector<const int, std::allocator<const int> >]()’
/usr/include/c++/4.3/ext/new_allocator.h: In member function ‘void __gnu_cxx::new_allocator<_Tp>::deallocate(_Tp*, size_t) [with _Tp = const int]’:
/usr/include/c++/4.3/bits/stl_vector.h:150:   instantiated from ‘void std::_Vector_base<_Tp, _Alloc>::_M_deallocate(_Tp*, size_t) [with _Tp = const int, _Alloc = std::allocator<const int>]’
/usr/include/c++/4.3/bits/stl_vector.h:136:   instantiated from ‘std::_Vector_base<_Tp, _Alloc>::~_Vector_base() [with _Tp = const int, _Alloc = std::allocator<const int>]’
/usr/include/c++/4.3/bits/stl_vector.h:286:   instantiated from ‘std::vector<_Tp, _Alloc>::vector(_InputIterator, _InputIterator, const _Alloc&) [with _InputIterator = const int*, _Tp = const int, _Alloc = std::allocator<const int>]’
Filter.cpp:29:   instantiated from here
/usr/include/c++/4.3/ext/new_allocator.h:98: error: invalid conversion from ‘const void*’ to ‘void*’
/usr/include/c++/4.3/ext/new_allocator.h:98: error:   initializing argument 1 of ‘void operator delete(void*)’
/usr/include/c++/4.3/bits/stl_algobase.h: In function ‘_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = false, _II = const int*, _OI = const int*]’:
/usr/include/c++/4.3/bits/stl_algobase.h:435:   instantiated from ‘_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = false, _II = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >, _OI = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >]’
/usr/include/c++/4.3/bits/stl_algobase.h:466:   instantiated from ‘_OI std::copy(_II, _II, _OI) [with _II = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >, _OI = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >]’
/usr/include/c++/4.3/bits/vector.tcc:136:   instantiated from ‘__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> > std::vector<_Tp, _Alloc>::erase(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, __gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >) [with _Tp = const int, _Alloc = std::allocator<const int>]’
Filter.cpp:23:   instantiated from ‘Container<A, Allocator> filter(const Container<A, Allocator>&, const Predicate&) [with Container = std::vector, Predicate = bool ()(int), Allocator = std::allocator<const int>, A = const int]’
Filter.cpp:30:   instantiated from here
/usr/include/c++/4.3/bits/stl_algobase.h:396: error: no matching function for call to ‘std::__copy_move<false, true, std::random_access_iterator_tag>::__copy_m(const int*&, const int*&, const int*&)’

/usr/include/c++/4.3/ext/new\u allocator.h:在“\u gnu\u cxx:：new\u allocator”的实例化中：
/usr/include/c++/4.3/bits/allocator.h:84:从“std:：allocator”实例化
/usr/include/c++/4.3/bits/stl_vector.h:75:从“std:：_vector_base”实例化
/usr/include/c++/4.3/bits/stl_vector.h:176:从“std:：vector”实例化
Filter.cpp:29:从此处实例化
/usr/include/c++/4.3/ext/new_allocator.h:82:错误：“const\u Tp*\uu\u gnu\u cxx:：new_allocator:：address（const\u Tp&）const[with _Tp=const int]”无法重载
/usr/include/c++/4.3/ext/new_allocator.h:79:错误：带有“\u-Tp*\u-gnu\u-cxx:：new_allocator:：address（\u-Tp&）const[带有\u-Tp=const-int]”
Filter.cpp:在函数“Container Filter（const Container&，const Predicate&）[with Container=std:：vector，Predicate=bool（）（int），Allocator=std:：Allocator，A=const int]”中：
Filter.cpp:30:从此处实例化
Filter.cpp:23:错误：将“const std:：vector”作为“\uu gnu\u cxx:：\uuu normal\u迭代器std:：vector:：erase”（\uu gnu\u cxx:：\uu normal\u迭代器，\uu gnu cxx:：\uu normal\u迭代器）[with\u Tp const int，\u Alloc=std:：分配器]”的“此”参数传递将丢弃限定符
/usr/include/c++/4.3/bits/stl_algo.h:在函数“\u FIter std:：remove_if（\u FIter，\u FIter，\u Predicate，\u Predicate）[使用_FIter=\u gnu\u cxx:：\u normal\u迭代器，\u Predicate=bool（*）（int）]中：
Filter.cpp:23:从“容器过滤器（常量容器和常量谓词）实例化[容器=std:：vector，谓词=bool（）（int），分配器=std:：分配器，A=const int]”
Filter.cpp:30:从此处实例化
/usr/include/c++/4.3/bits/stl_-algo.h:821:错误：分配只读位置“\uu结果.\uuu-gnu\u-cxx:：\uuu-normal\u迭代器：：运算符*[带u-iterator=const int*，\u-Container=std:：vector]（）”
/usr/include/c++/4.3/ext/new_allocator.h:在成员函数“void\u gnu\u cxx:：new_allocator:：deallocate（_Tp*，size\u t）[带_Tp=const int]”：
/usr/include/c++/4.3/bits/stl_vector.h:150:从“void std:：_vector_base:：：_M_deallocate（_Tp*，size_t）[带_Tp=const int，_Alloc=std:：allocator]”实例化
/usr/include/c++/4.3/bits/stl_vector.h:136：从“std:：_vector_base:：~_vector_base（）[with _Tp=const int，_Alloc=std:：allocator]实例化”
/usr/include/c++/4.3/bits/stl_vector.h:286:从“std:：vector:：vector（_inputierator，_inputierator，const)Alloc&）[带_inputierator=const int*，_Tp=const int，_Alloc=std:：alloctor]”实例化
Filter.cpp:29:从此处实例化
/usr/include/c++/4.3/ext/new_allocator.h:98:错误：从“const void*”到“void*”的转换无效
/usr/include/c++/4.3/ext/new_allocator.h:98:错误：初始化“void operator delete（void*）”的参数1
/usr/include/c++/4.3/bits/stl_algobase.h:在函数“_oistd:：__copy_move_a（_II，_II，_OI）[其中bool_IsMove=false，_II=const int*，_OI=const int*]”中：
/usr/include/c++/4.3/bits/stl_algobase.h:435:实例化自“_oistd:：__copy_move_a2”（_II，_II，_OI）[带bool _IsMove=false，_II=_gnucxx:_normal_迭代器，_OI=_gnucxx:_normal迭代器]”
/usr/include/c++/4.3/bits/stl_algobase.h:466：实例化自“_oistd:：copy（_II，_II，_OI）[带_II=_gnucxx:：_normal_迭代器，_OI=_gnucxx:_normal_迭代器]”
/usr/include/c++/4.3/bits/vector.tcc:136:实例化自“uu gnu cxx:：u normal_迭代器std:：vector:：erase”（uu gnu cxx:：u normal_迭代器，uu gnu cxx:：u normal_u迭代器）[带Tp=const int，u Alloc=std:：分配器]”
Filter.cpp:23:从“容器过滤器（常量容器和常量谓词）实例化[容器=std:：vector，谓词=bool（）（int），分配器=std:：分配器，A=const int]”
Filter.cpp:30:从此处实例化
/usr/include/c++/4.3/bits/stl_algobase.h:396:错误：调用“std:：_copy_move:：_copy_m（const int*&，const int*&，const int*&）”时没有匹配函数

请告诉我我做错了什么，以及实现我想要的高阶多态性的正确方法是什么

谢谢

编辑：

谢谢大家。这是我在应用了你的建议后得到的新代码（现在它可以工作了，耶！）

#包括
#包括
#包括
#包括
#包括
#包括
#包括
使用名称空间std；
布尔isOdd（内部常数i）{
返回i%2！=0；
}
模板<
模板类容器，
类型名谓词，
类型名分配器，
类型名A
>
容器过滤器（容器常量和容器、谓词常量和pred）{
容器过滤（容器）；
filtered.erase（如果（filtered.begin（）、filtered.end（）、pred）、filtered.end（））删除_）；
返回过滤；
}
int main（）{
INTA[]={23,12,78,21,97,64}；
向量v（a，a+6）；
向量过滤=过滤器（v，isOdd）；
复制（filtered.begin（）、filtered.end（）、ostream_迭代器（cout，“”）；
}

为什么您的

容器要参数化

template <typename C, typename P>
C filter(C const & container, P pred) {
  C filtered(container);
  filtered.erase(remove_if(filtered.begin(), filtered.end(), pred), filtered.end());
  return filtered;
}

模板
C过滤器（C容器和容器，P pred）{
C过滤（容器）；
过滤。擦除（如果（fil）则删除
template <typename C, typename P>
C filter(C const & container, P pred) {
  C filtered(container);
  filtered.erase(remove_if(filtered.begin(), filtered.end(), pred), filtered.end());
  return filtered;
}

int main() {
  int const a[] = {23, 12, 78, 21, 97, 64};
  vector<int const> const v(a, a + 6);
}

int main() {
  int const a[] = {23, 12, 78, 21, 97, 64};
  vector<int> const v(a, a + 6);
}

filtered.erase(remove_if(filtered.begin(), filtered.end(), pred), filtered.end());