fork(3) download

copy

#include <iostream>
 
class T {
public:
    int a, b;
    T (int _a = 0, int _b = 0) : a(_a), b(_b) { } // konwersja int -> T, nie moze byc explicit
 
    friend T operator+ (const T &a, const T &b) {
        return T(a.a + b.a, a.b + b.b);
    }
 
    operator bool () { return (this->b != 0 || this->a != 0); } // bez tego dziala (?)
 
    operator int() = delete; // zabroniona konwersja T -> int (!)
};
 
int main () {
    T a(1, 3);
    std::cout << (a + 1).a << ' ' << (a + 1).b;
    return 0;
}

prog.cpp: In function 'int main()':
prog.cpp:19:21: error: ambiguous overload for 'operator+' (operand types are 'T' and 'int')
     std::cout << (a + 1).a << ' ' << (a + 1).b;
                     ^
prog.cpp:19:21: note: candidates are:
prog.cpp:19:21: note: operator+(int, int) <built-in>
prog.cpp:8:14: note: T operator+(const T&, const T&)
     friend T operator+ (const T &a, const T &b) {
              ^
prog.cpp:19:41: error: ambiguous overload for 'operator+' (operand types are 'T' and 'int')
     std::cout << (a + 1).a << ' ' << (a + 1).b;
                                         ^
prog.cpp:19:41: note: candidates are:
prog.cpp:19:41: note: operator+(int, int) <built-in>
prog.cpp:8:14: note: T operator+(const T&, const T&)
     friend T operator+ (const T &a, const T &b) {
              ^

Standard output is empty