Question

#include <iosteam>
using namespace std;

Class A
{
  int k;

public:

  int getK() { return k; }

  operator int() { return k; }

};

int main()
{
  A a;
  cout << a.getK() << " " << int(a) << endl;
}

What’s the difference, and which one should I use? I’m wondering if typecasting returns a reference and getK returns a copy.

Answer 1

The only difference is that typecasting can be implicit.

int i = a;

Note that c++11 allow you to force cast operator to be explicitly called.

explicit operator int() { return k; }