unique_ptr.cpp

#include <iostream>
#include <memory>

using namespace std;

unique_ptr<int> factory(int i)
{
    return unique_ptr<int>(new int(i));
}

void client(unique_ptr<int> p)
{
    // Ownership transferred into client
}   // int* deleted here

int main()
{
    unique_ptr<int> p = factory(2);
    // *p == 2
    p.reset(new int(3));
    // *p == 3
    client(move(p));  // ok now
    // p is "null" here
    if (p)
            std::cout << "p is " << *p << std::endl;
    else
            std::cout << "p is null " << std::endl;
    return 0;

}
// returns 'p is null'
// source https://howardhinnant.github.io/unique_ptr03.html