c++ - 是否可以使结构直接返回值？

Question

我希望能够在结构被调用时直接从它返回一个值，而不是通过它的成员函数访问我想要的东西。这可能吗？

例如:

#include <iostream>

using namespace std;

enum FACE { NORTH, SOUTH, EAST, WEST };

struct Direction {
    FACE face;
};

int main(){
    Direction dir;
    dir.face = EAST;

    cout << dir;  // I want this to print EAST instead of having to do dir.face
}

Answer 1

您可以添加转换运算符FACE:

struct Direction {
    // .. Previous code

    operator FACE () const { return face; }
};

Live example