CPP_SmartPtr_09.cpp

void foo(unique_ptr<Dog> p){
    p->bark();
}

unique_ptr<Dog> getDog(){
    unique_ptr<Dog> p(new Dog("Jack"));
    //return p will use the move semantics! 
    //so p will no longer has the ownership of Jack
    return p;
}

void test03(){
    unique_ptr<Dog> pD (new Dog("DND"));
    //Cannot directly pass to foo(), since pD is unique pointer. 
    //pD will be destroyed in foo().
    foo(move(pD));

    //pD2 owns the jack now, so it's not nullptr!
    unique_ptr<Dog> pD2 = getDog();
    if(!pD2) {cout << "pD2 is nullptr. " << endl;}
}