//observe that move semantic is used when emplace_back is done at size == capacity //just remove noexcept and observe that copy is used instead of move #include #include #include using namespace std; class test { char* m_name; int m_size; public: test() : test("Unknown") { cout << " Default constructor called\n"; } test(string name) { cout << " Parametric constructor called for " << name << "\n"; m_size = name.size() + 1;//1 for null char m_name = new char[m_size]; strcpy(m_name,(const char*)name.c_str()); } test(const test& obj) { cout << " Copy constructor called from " << obj.m_name << "\n"; m_size = obj.m_size; m_name = new char[m_size]; strcpy(m_name,obj.m_name); } test(test&& obj) noexcept { cout << " move constructor called from " << obj.m_name << "\n"; m_size = obj.m_size; m_name = obj.m_name; obj.m_name = nullptr; obj.m_size = 0; } test& operator=(const test& obj) { cout << " Copy assignment called from " << obj.m_name << "\n"; delete[] m_name; m_name = nullptr; m_size = 0; m_size = obj.m_size; m_name = new char[m_size]; strcpy(m_name, obj.m_name); return *this; } test& operator=(test&& obj)noexcept { cout << " move assignment called from " << obj.m_name << "\n"; if (this != &obj)//avoid destructing on self assignment { delete[] m_name; m_name = nullptr; m_size = 0; m_size = obj.m_size; m_name = obj.m_name; obj.m_name = nullptr; obj.m_size = 0; } return *this; } ~test() { if (m_name != nullptr) { cout << " Destructor called for " << m_name << "\n"; delete[] m_name; m_name = nullptr; m_size = 0; } } void display() { cout << "Hi " << m_name << endl; } }; void myClassMemberTests() { test t1("Ketan"); t1.display(); test t2(t1); t2.display(); test t3; t3.display(); t3 = t2; t3.display(); test t4("Lalcheta"); t4.display(); test t5(move(t4)); t5.display(); test t6; t6.display(); t6 = move(t5); t6.display(); } int main() { //myClassMemberTests(); vector vTest; vTest.emplace_back("Ketan"); cout << "First emplace back\n"; vTest.emplace_back("Lalcheta"); cout << "Second emplace back\n"; return 0; }

VectorSTL_MoveConstructor