The following code example is taken from the book
C++ Move Semantics - The Complete Guide
by Nicolai M. Josuttis,
Leanpub, 2020
The code is licensed under a
Creative Commons Attribution 4.0 International License.
// raw code
#include <iostream>
#include <string>
#include <memory>
std::unique_ptr<std::string> source()
{
static long id{0};
// create string with new and let ptr own it:
auto ptr = std::make_unique<std::string>("obj" + std::to_string(++id));
//...
return ptr; // transfer ownership to caller
}
int main()
{
std::unique_ptr<std::string> p;
for (int i = 0; i < 10; ++i) {
p = source(); // p gets ownership of the returned object
// (previously returned object of source() is deleted)
std::cout << *p << '\n';
//...
}
} // last-owned object of p is deleted