MonStructCommaAdd.cpp

MonStructCommaAdd.cpp

#include <iostream>
#include <string>

// Trying to understand / implement myself the magic behind
// https://www.boost.org/doc/libs/1_74_0/libs/assign/doc/index.html#operator+=

template<typename ... Ts>
void Print(const char * format, Ts ... ts) {
    char buffer[256];
    std::sprintf(buffer, format, ts ...);
    std::cout << buffer << '\n';
}

struct MonStruct {
    int x = 0;
    MonStruct (int pX) : x(pX) {}
    
    friend MonStruct & operator+=(MonStruct & lhs, int rhs) {
        Print("MonStruct(%d) += int(%d)", lhs.x, rhs);
        lhs.x += rhs;
        return lhs;
    }

    friend MonStruct & operator,(MonStruct & lhs, int rhs) {
        Print("MonStruct(%d), int(%d)", lhs.x, rhs);
        lhs.x += rhs;
        return lhs;
    }
};

int main() {
    MonStruct monStruct(1);
    monStruct += 10, 100, 1000, 10000;

    Print("R = MonStruct(%d)", monStruct.x);
    
    // MonStruct(1) += int(10)
    // MonStruct(11), int(100)
    // MonStruct(111), int(1000)
    // MonStruct(1111), int(10000)
    // R = MonStruct(11111)
}