c++ - Can the virtual function be found at runtime without calling? -


i have base class base, many derived classes (eg. derived1, derived2). base has pure virtual function fn, called many times using base pointer. every time function called, need logging , related stuff. in particular, use boost_current_function in derived-class functions find out function called. there way know information before calling function, not have rewrite bookkeeping code in every derived function?

edit: wish avoid writing __pretty_function__ in each derived function.

#include <iostream> using namespace std;  class base { public: virtual void fn() = 0; };  class derived1:public base { public: void fn() { cout<<__pretty_function__<<endl; } };  class derived2:public base { public: void fn() { cout<<__pretty_function__<<endl; } };  int main() {     int choice =0;     base *ptr1 = nullptr;     cout<<"choose 0/1: "<<endl;     cin>>choice;     if(choice == 0) {            ptr1 = new derived1;     }else {        ptr1 = new derived2;     }      //********can write here, give same result?     ptr1->fn(); }

no, cannot be. c++ not support kind of introspection. __pretty_function__ you're gonna get.


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