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- std::bind overload resolution 2 answers
I am currently working on a program that needs to use std::bind to bind arguments to a member function, but when I attempt to do so, I get a compiler error. The following is a minimum example:
Map.h:
#pragma once
class Map {
void buildDistances();
void buildDistances(unsigned islandId);
};
Map.cpp:
#include "Map.h"
#include <functional>
void Map::buildDistances() {
for(unsigned islandId=0;islandId<24;++islandId){
auto f = std::bind(&Map::buildDistances, this, islandId);
f();
}
}
void Map::buildDistances(unsigned islandId) {}
Compiling with the command g++ Map.cpp -c -o map.o
in the same directory as both of these files produces the following error:
Map.cpp: In member function ‘void Map::buildDistances()’:
Map.cpp:7:64: error: no matching function for call to ‘bind(<unresolved overloaded function type>, Map*, unsigned int&)’
auto f = std::bind(&Map::buildDistances, this, islandId);
^
In file included from Map.cpp:3:
/usr/include/c++/8.1.1/functional:808:5: note: candidate: ‘template<class _Func, class ... _BoundArgs> typename std::_Bind_helper<std::__is_socketlike<_Func>::value, _Func, _BoundArgs ...>::type std::bind(_Func&&, _BoundArgs&& ...)’
bind(_Func&& __f, _BoundArgs&&... __args)
^~~~
/usr/include/c++/8.1.1/functional:808:5: note: template argument deduction/substitution failed:
Map.cpp:7:64: note: couldn't deduce template parameter ‘_Func’
auto f = std::bind(&Map::buildDistances, this, islandId);
^
In file included from Map.cpp:3:
/usr/include/c++/8.1.1/functional:832:5: note: candidate: ‘template<class _Result, class _Func, class ... _BoundArgs> typename std::_Bindres_helper<_Result, _Func, _BoundArgs>::type std::bind(_Func&&, _BoundArgs&& ...)’
bind(_Func&& __f, _BoundArgs&&... __args)
^~~~
/usr/include/c++/8.1.1/functional:832:5: note: template argument deduction/substitution failed:
Map.cpp:7:64: note: couldn't deduce template parameter ‘_Result’
auto f = std::bind(&Map::buildDistances, this, islandId);
Why is this happening, and how can I fix it? I attempted to find a result by putting parts of the error in a search engine, but nothing useful came up. I also tried compiling with clang, which produces the same error.
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