是否可以将友元函数声明为静态函数?

Is it possible to declare a friend function as static?(是否可以将友元函数声明为静态函数?)

问题描述

这里是一些编译和工作正常的 C++ 示例代码:

Here is some C++ example code that compiles and works fine:

class A
{
public:
   A() {/* empty *