rtti - Print type of object referenced by base-class pointer in C++? -


if have class a, , class b subclasses a, should typeid(x) give type of or type of b, if x given by:

a *x = new b();

in tests type of - not useful - i'm not sure if that's due how c++ works, or if due compiler settings?

example code:

#include <iostream> #include <typeinfo>  // remember add virtual member function in // enable rtti. struct { virtual ~a() {} };  struct b : { virtual ~b() {}};  int main() {    a* ap = new b();    std::cout << typeid(ap).name() << std::endl;    std::cout << typeid(*ap).name() << std::endl; }

output, g++ 4.8.2:

 p1a 1b

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