拷贝构造和operator=的区别

简单总结下：

对于在赋值操作之前，还未构造的变量，调用拷贝构造函数（Copy Constructor);

对于在赋值之前，已经构造的变量，调用赋值操作(Assignment Operator);

#include <iostream>


class A
{
public:
	A(){ std::cout << "A()" << std::endl; };
	A(const A& rhs){ std::cout << "copy constructor" << std::endl;; }
	A& operator=(const A& rhs){ std::cout << "operator=" << std::endl; return *this; }
};
A test()
{
	A a;
	return a;
}
int main()
{
	A a;
	A b = a;		// copy constructor


	A c;
	c = a;			// operator=


	c = test();		// operator=


	A d = test();	// copy constructor
}