Passing pointer to member function to parent in c++ -

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how can make following code work? can't make members static, parent doesn't know child , don't have access boost. reason don't use virtual functions child class should able define 1-n handlers.

class parent { public:     void registerfilehandler(string ext, memfuncptr); };  class child : public parent {     child()     {         registerfilehandler("jpg", &child::loadjpg);         registerfilehandler("png", &child::loadpng);     }     void loadjpg(string filename);     void loadpng(string filename); };

edit: there many answers. ones works best me use keywords erasure, std::bind , std::function of course rely on c++11. here full compilable example:

#include <string> #include <map> #include <iostream> #include <functional>  using namespace std;  class parent { public:     void load(string filename)     {         // see if can find handler based on extension.         for(auto = handlers.begin();it!=handlers.end();it++)             if(filename.substr(filename.size()-it->first.size(), it->first.size())==it->first)                 it->second(filename);     }     template<typename class>     void registerfilehandler(class* p, void (class::*func)(string), string ext)     {         using namespace std::placeholders; //for _1, _2, _3...         handlers[ext] = std::bind(func, p, _1);     } private:     map<string, std::function<void(string)> > handlers; };  class child : public parent { public:     child()     {         registerfilehandler(this, &child::loadjpg, "jpg");         registerfilehandler(this, &child::loadpng, "png");     }     void loadjpg(string filename)     {         cout << "loading jpeg "<< filename << endl;     }     void loadpng(string filename)     {         cout << "loading png "<< filename << endl;     } };   int main(int argc, char* argv[]) {     child child;     child.load("blah.jpg");     child.load("blah.png");     return 0; }

how std::function , std::bind:

class parent { public:      void registerfilehandler(string ext, const std::function<void(string)> &f)     {     } };  class child : public parent { public:     child()     {         using namespace std::placeholders; //for _1, _2, _3...         registerfilehandler("jpg", std::bind(&child::loadjpg, this, _1));         registerfilehandler("png", std::bind(&child::loadpng, this, _1));     }      ...

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