C++多层 initializer_list 的传递和初始化技巧

class AVD {

public:

AVD(){

std::cout << 1;

}

AVD(std::initializer_list<AVD> Val):Val_(Val){

std::cout << 2;

}

AVD(std::initializer_list<int> Val) {

std::cout << 3;

}

void df() {

std::cout << 4;

}

private:

    std::initializer_list<AVD> Val_;

};

AVD DF({ {1,2},{2,3} });