std::map of method function pointer doesn't compile

Question

I've got a nice error when I try to insert my map of method pointer:

nts::IComponent *builder::createComponent(const std::string &type,
const std::string &value) {
        fptr ptr = listFunction[type];
        return (ptr(value));
    }

builder::builder() {
        listFunction.insert(make_pair("4081", &builder::create4081));
    }

nts::IComponent *builder::create4081(string const &value) const {
        return new c4081(value);
    }

Here's the definition:

class builder {
    typedef IComponent *(*fptr)(string const &);
private:
    map<string, fptr const> listFunction;

    //composants
    IComponent *create4081(string const &) const;
public:
    builder();
    IComponent *createComponent(const std::string &type, const std::string &value);

};

And here's the error:

home/aherys/Documents/nanotekspicelib/builder.cpp: Dans le constructeur « builder::builder() »:
/home/aherys/Documents/nanotekspicelib/builder.cpp:15:64: erreur : no matching function for call to « std::map<std::__cxx11::basic_string<char>, nts::IComponent* (* const)(const std::__cxx11::basic_string<char>&)>::insert(std::pair<const char*, nts::IComponent* (builder::*)(const std::__cxx11::basic_string<char>&) const>) »
     listFunction.insert(make_pair("4081", &builder::create4081));
                                                                ^
In file included from /usr/include/c++/6.3.1/map:61:0,
                 from /home/aherys/Documents/nanotekspicelib/builder.h:10,
                 from /home/aherys/Documents/nanotekspicelib/builder.cpp:5:
/usr/include/c++/6.3.1/bits/stl_map.h:731:7: note : candidate: std::pair<typename std::_Rb_tree<_Key, std::pair<const _Key, _Tp>, std::_Select1st<std::pair<const _Key, _Tp> >, _Compare, typename __gnu_cxx::__alloc_traits<_Alloc>::rebind<std::pair<const _Key, _Tp> >::other>::iterator, bool> std::map<_Key, _Tp, _Compare, _Alloc>::insert(const value_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = nts::IComponent* (* const)(const std::__cxx11::basic_string<char>&); _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, nts::IComponent* (* const)(const std::__cxx11::basic_string<char>&)> >; typename std::_Rb_tree<_Key, std::pair<const _Key, _Tp>, std::_Select1st<std::pair<const _Key, _Tp> >, _Compare, typename __gnu_cxx::__alloc_traits<_Alloc>::rebind<std::pair<const _Key, _Tp> >::other>::iterator = std::_Rb_tree_iterator<std::pair<const std::__cxx11::basic_string<char>, nts::IComponent* (* const)(const std::__cxx11::basic_string<char>&)> >; std::map<_Key, _Tp, _Compare, _Alloc>::value_type = std::pair<const std::__cxx11::basic_string<char>, nts::IComponent* (* const)(const std::__cxx11::basic_string<char>&)>]
       insert(const value_type& __x)

Trying a lot of things, but it look like I miss something. I didn't understand where is the syntax or dereference error. Can you explain?

A non static member function cannot be converted to a non member function pointer. — NathanOliver, Mar 03 '17 at 18:14
@Nathan Minor nitpick: _"A member function"_ `static` functions _are_ member functions as well. — πάντα ῥεῖ, Mar 03 '17 at 18:16
@Nathan We were quick enough about that, very good ;-) We should try to find the appropriate dupe now. — πάντα ῥεῖ, Mar 03 '17 at 18:18
The easiest way is to make the function static if you can. Otherwise use `std::function` in conjunction with a lambda or `bind`. Trying to find a dupe. This might work: http://stackoverflow.com/questions/8045322/c-function-callbacks-cannot-convert-from-a-member-function-to-a-function-sign — NathanOliver, Mar 03 '17 at 18:33

std::map of method function pointer doesn't compile

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