What are some examples of using unique_ptr in C++17?

Can you give me some examples of using unique_ptr in C++17?

Sure! In C++17, unique_ptr is a smart pointer that manages a dynamically allocated object. Here's a simple example:

#include <iostream>
#include <memory>

int main() {
    std::unique_ptr<int> ptr = std::make_unique<int>(10);
    std::cout << *ptr << std::endl; // Outputs: 10
    return 0;
}

This creates a unique pointer to an integer initialized to 10.

What happens if I try to copy a unique_ptr?

Good question! unique_ptr cannot be copied because it is designed to have a single owner. If you try to copy it, you'll get a compilation error. However, you can transfer ownership using std::move:

std::unique_ptr<int> ptr1 = std::make_unique<int>(20);
std::unique_ptr<int> ptr2 = std::move(ptr1); // ptr1 is now nullptr

Can I use unique_ptr with arrays?

Yes, you can! In C++17, you can use unique_ptr with arrays by specifying the array type:

std::unique_ptr<int[]> arr = std::make_unique<int[]>(5);

This creates a unique pointer to an array of 5 integers.

Are there any performance benefits to using unique_ptr?

Absolutely! unique_ptr has lower overhead compared to traditional pointers and helps prevent memory leaks by automatically deallocating memory when it goes out of scope. This can lead to better performance and safer code.