What are some examples of move semantics in C++?

What are some examples of move semantics in C++?

Move semantics in C++ allow resources to be transferred rather than copied. For example, using std::move with a vector.

Can you show me a code snippet that demonstrates this?

Sure! Here's a simple example:

#include <iostream>
#include <vector>
#include <utility> // for std::move

int main() {
    std::vector<int> vec1 = {1, 2, 3};
    std::vector<int> vec2 = std::move(vec1); // Move vec1 to vec2

    // vec1 is now empty
    std::cout << "vec1 size: " << vec1.size() << '\n';
    std::cout << "vec2 size: " << vec2.size() << '\n';
}

This transfers the ownership of the vector from vec1 to vec2.

What happens to vec1 after the move?

After the move, vec1 is in a valid but unspecified state, meaning it can be safely destructed but should not be used until reassigned.

Are there any performance benefits to using move semantics?

Yes, move semantics can significantly improve performance by eliminating unnecessary copies, especially for large objects.