std::unique_ptr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 5.4 std::weak_ptr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . std::cout << "Foo::~Foo" << std::endl; } void foo() { std::cout << "Foo::foo" << std::endl; } }; 59 5.4 std::weak_ptr CHAPTER 05 SMART POINTERS AND MEMORY MANAGEMENT void f(const Foo &) { std::cout << not empty, prints if (p1) p1->foo(); // Foo instance will be destroyed when leaving the scope } 5.4 std::weak_ptr If you think about std::shared_ptr carefully, you will still find that there is still

maximum memory needs. Fanchen Su, XOffsetDatastructure, CppCon 2024 88 Per-allocation with Trimming5.4 Auto-Resizing Mechanisms • 2. Auto-Resizing: • For greater ease of use, we've also implemented auto-resizing entire buffer to be moved in memory. Fanchen Su, XOffsetDatastructure, CppCon 2024 89 Auto-Resizing5.4 Auto-Resizing Mechanisms • We've implemented the auto-resizing functionality using three different CppCon 2024 90 Method Time (ms) Exception 1735 longjmp 1395 Leaf 3177 Performance Comparison5.4 Auto-Resizing Mechanisms • We've implemented the auto-resizing functionality using three different

std::unique_ptr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 5.4 std::weak_ptr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 以利用 std::move 将其转移给其他的 unique_ptr，例如： #include #include struct Foo { 54 5.4 std::weak_ptr 第 5 章智能指针与内存管理 Foo() { std::cout << "Foo::Foo" << std::endl; } ~Foo() { std::cout << 的实例会在离开作用域时被销毁 } 5.4 std::weak_ptr 如果你仔细思考 std::shared_ptr 就会发现依然存在着资源无法释放的问题。看下面这个例子： struct A; struct B; struct A { std::shared_ptr pointer; ~A() { std::cout << "A 被销毁" << std::endl; 55 5.4 std::weak_ptr