c++ function ptr in unorderer_map, compile time error -

i trying implements unorderer_map implements mapped_type, watching examples implements these cannot make work. here code:

#include<string> #include <unordered_map> namespace test {   class example   {   public:     example()     {       auto apair=std::make_pair("one",&example::processtring);       map.insert(apair);     }     void processtring(std::string & astring)     {      }     void processstringtwo(std::string & astring)     {      }     typedef void(*fnptr)(std::string &);     std::unordered_map<std::string,fnptr> map;   }; }  int main() {   return 0; } 

i compile time error:

error: no matching function call 'std::unordered_map, void (*)(std::basic_string&)>::insert(std::pair, void (test::example::*)(std::basic_string&)>&)'

thx!

a function pointer , member function pointer 2 different things. either need add free function map or need change map take member function pointer instead. if want take member function pointer can use this:

typedef void(example::*fnptr)(std::string &);