Problems with move semantics in a custom container class in C++11
Quick question that's been bugging me - I've searched everywhere and can't find a clear answer. I'm sure I'm missing something obvious here, but I'm currently implementing a custom container class in C++11, and I'm running into issues with move semantics. I want to ensure that my container efficiently transfers ownership of its elements when a temporary instance is created, but I'm working with unexpected behavior when I try to move my container. Here's a simplified version of my code: ```cpp #include <iostream> #include <vector> #include <utility> template <typename T> class MyContainer { public: MyContainer() = default; // Move constructor MyContainer(MyContainer&& other) noexcept : data(std::move(other.data)) { std::cout << "Move constructor called" << std::endl; } // Move assignment operator MyContainer& operator=(MyContainer&& other) noexcept { if (this != &other) { data = std::move(other.data); std::cout << "Move assignment operator called" << std::endl; } return *this; } void add(const T& value) { data.push_back(value); } private: std::vector<T> data; }; int main() { MyContainer<int> container1; container1.add(1); container1.add(2); MyContainer<int> container2 = std::move(container1); // container1 should be in a valid but unspecified state } ``` When I run this code, I see the message from the move constructor, but when I inspect `container2`, it appears to be empty, and I don't see any messages indicating that the move assignment operator was called. I thought that the move constructor should transfer the contents from `container1` to `container2`, but it seems `container1` is still holding onto its data instead of being left in a valid but unspecified state. I've tried adding debug print statements in different parts of the code, but I still need to figure out where things are going wrong. Am I missing something in my implementation of move semantics? What should I be doing differently to ensure that the move operation works as expected? For context: I'm using C++ on macOS. Thanks in advance! This is part of a larger web app I'm building. I'd really appreciate any guidance on this. I'm coming from a different tech stack and learning C++.