// // 3.4.cpp // c++1x tutorial // // created by changkun at shiyanlou.com // // 移动语义 #include class A { public: int *pointer; A():pointer(new int(1)) { std::cout << "构造" << pointer << std::endl; } A(A& a):pointer(new int(*a.pointer)) { std::cout << "拷贝" << pointer << std::endl; } // 无意义的对象拷贝 A(A&& a):pointer(a.pointer) { a.pointer = nullptr;std::cout << "移动" << pointer << std::endl; } ~A(){ std::cout << "析构" << pointer << std::endl; delete pointer; } }; // 防止编译器优化 A return_rvalue(bool test) { A a,b; if(test) return a; else return b; } int main() { A obj = return_rvalue(false); std::cout << "obj:" << std::endl; std::cout << obj.pointer << std::endl; std::cout << *obj.pointer << std::endl; return 0; }