我试图用这样的非朋友非成员函数重载逗号运算符：

#include <iostream>
using std::cout;
using std::endl;

class comma_op
{
    int val;

public:
    void operator,(const float &rhs)
    {
        cout << this->val << "," << rhs << endl;
    }
};

void operator,(const float &lhs,const comma_op &rhs)
{
    cout << "Reached!\n";      // this gets printed though
    rhs,lhs;                  // reversing this leads to a infinite recursion ;)
}

int main()
{
    comma_op obj;
    12.5f,obj;

    return 0;
}

@H_404_4@基本上,我试图让浮点数从两边使用逗号运算符.拥有成员函数只允许我编写obj,float_val,而有一个额外的帮助非朋友非成员函数允许我编写float_val,obj;但是不会调用成员操作符函数.

@H_404_4@GCC哭泣：

comma.cpp: In function ‘void operator,(const float&,const comma_op&)’:
comma.cpp:19: warning: left-hand operand of comma has no effect
comma.cpp:19: warning: right-hand operand of comma has no effect

@H_404_4@注意：
我意识到重载运算符,这也会使逗号超载,令人困惑,从纯粹主义者的角度来看也是不可取的.我只是在这里学习C语言的细微差别.

void operator,(const float &rhs)

void operator,(const float &rhs) const {
    cout << this->val << "," << rhs << endl;
}

rhs,lhs

rhs.operator,(lhs)