obj3.cpp

//
// Created by light on 19-12-22.
//

#include <iostream>

using namespace std;

// Can copy and move
class A {
public:
  A() { cout << "Create A\n"; }

  ~A() { cout << "Destroy A\n"; }

  A(const A &) { cout << "Copy A\n"; }

  A(A &&) { cout << "Move A\n"; }

  A &operator=(const A &a) {
    std::cout << "copy assignment" << std::endl;
    return *this;
  }

  A &operator=(A &&a) {
    cout << "move assignment\n";
    return *this;
  }
};
// 编译器无法优化
A getA_duang() {
  A a1;
  A a2;
  if (rand() > 42) {
    return a1;
  } else {
    return a2;
  }
}

int main() {
  //    cout<<"拷贝"<<endl;
  //    auto a = getA_duang();

  cout << "赋值" << endl;
  A aa;
  aa = getA_duang();
}