我有一个小程序,我想执行测试的东西有问题的std ::地图和std ::对
#include <map>
#include <iostream>
using namespace std;
struct _pos{
float xi;
float xf;
bool operator<(_pos& other){
return this->xi < other.xi;
}
};
struct _val{
float f;
};
int main()
{
map<_pos,_val> m;
struct _pos k1 = {0,10};
struct _pos k2 = {10,15};
struct _val v1 = {5.5};
struct _val v2 = {12.3};
m.insert(std::pair<_pos,_val>(k1,v1));
m.insert(std::pair<_pos,_val>(k2,v2));
return 0;
}
的问题是,当我尝试编译它,我得到以下错误
$ g++ m2.cpp -o mtest
In file included from /usr/include/c++/4.4/bits/stl_tree.h:64,
from /usr/include/c++/4.4/map:60,
from m2.cpp:1:
/usr/include/c++/4.4/bits/stl_function.h: In member function ‘bool std::less<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = _pos]’:
/usr/include/c++/4.4/bits/stl_tree.h:1170: instantiated from ‘std::pair<typename std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::iterator, bool> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_insert_unique(const _Val&) [with _Key = _pos, _Val = std::pair<const _pos, _val>, _KeyOfValue = std::_Select1st<std::pair<const _pos, _val> >, _Compare = std::less<_pos>, _Alloc = std::allocator<std::pair<const _pos, _val> >]’
/usr/include/c++/4.4/bits/stl_map.h:500: instantiated from ‘std::pair<typename std::_Rb_tree<_Key, std::pair<const _Key, _Tp>, std::_Select1st<std::pair<const _Key, _Tp> >, _Compare, typename _Alloc::rebind<std::pair<const _Key, _Tp> >::other>::iterator, bool> std::map<_Key, _Tp, _Compare, _Alloc>::insert(const std::pair<const _Key, _Tp>&) [with _Key = _pos, _Tp = _val, _Compare = std::less<_pos>, _Alloc = std::allocator<std::pair<const _pos, _val> >]’
m2.cpp:30: instantiated from here
/usr/include/c++/4.4/bits/stl_function.h:230: error: no match for ‘operator<’ in ‘__x < __y’
m2.cpp:9: note: candidates are: bool _pos::operator<(_pos&)
$
我认为声明运营商<的关键将解决问题,但它仍然存在。
什么可能是错的?
在此先感谢。
在C++中以双下划线开头的所有标识符,一个下划线跟着一个大写字母或一个下划线,然后在全局命名空间小写字母被保留用于执行。标识符'_pos'和'_val'应该被改变。 – 2010-04-15 07:17:13
@大卫·罗德里格斯。谢谢,会做,并牢记在心。 – Tom 2010-04-15 13:22:50