C++ set容器重写比较运算符报错：static assertion failed: comparison object must be invocable as const

 is_invocable_v,
	      "comparison object must be invocable as const");

报错时跳转位置，下面的注释讲得很清楚。C++17 需要为参数添加const修饰！

具体方法如下：

class MySort
{
public:
    bool operator()( Person  ob1,  Person  ob2)const
    {

        return ob1.score > ob2.score;
    }
};

很简单，就是在原来的参数列表之后加上const修饰！