Can you explain how the semantics of object movement are implemented in C++?

Move semantics in C++ allows efficient transfer of resources (e.g., memory) from one object to another without copying. This is implemented using rvalue references and special move constructors and operators.

Key points:

• The move constructor takes an rvalue reference (Type&&) and 'steals' resources from a temporary object.
• After moving, the original object remains in a valid but unspecified state (usually with null or empty resources).

Example:

class Buffer {
    char* data;
    size_t size;
public:
    Buffer(size_t s) : size(s), data(new char[s]) {}
    ~Buffer() { delete[] data; }

    // Move constructor
    Buffer(Buffer&& other) noexcept : data(other.data), size(other.size) {
        other.data = nullptr;
        other.size = 0;
    }

    // Move assignment operator
    Buffer& operator=(Buffer&& other) noexcept {
        if (this != &other) {
            delete[] data;
            data = other.data;
            size = other.size;
            other.data = nullptr;
            other.size = 0;
        }
        return *this;
    }

    // Delete copy constructor and copy assignment for clarity
    Buffer(const Buffer&) = delete;
    Buffer& operator=(const Buffer&) = delete;
};

Thus, move semantics help avoid costly copying of large resources, improving performance.