# std::experimental::weak_ptr

From cppreference.com
< cpp‎ | experimental

Defined in header `<experimental/memory>` |  |
template< class T > class weak_ptr; |  | (library fundamentals TS)

`std::experimental::weak_ptr` is a modified version of std::weak_ptr that interoperates with std::experimental::shared_ptr and has support for arrays.

### Member types

Member type | Definition
element_type | std::remove_extent_t <T>

### Member functions

(constructor) | constructs new `weak_ptr` (public member function)

## Members and non-members identical to std::weak_ptr

### Member functions

The following member functions work with std::experimental::shared_ptr instead of std::shared_ptr and std::experimental::weak_ptr instead of std::weak_ptr. The behavior is otherwise identical.

(destructor) | destroys a `weak_ptr` (public member function of `std::weak_ptr<T>`)
operator= | assigns the `weak_ptr` (public member function of `std::weak_ptr<T>`)

##### Modifiers

reset | releases the ownership of the managed object (public member function of `std::weak_ptr<T>`)
swap | swaps the managed objects (public member function of `std::weak_ptr<T>`)

##### Observers

use_count | returns the number of `shared_ptr` objects that manage the object (public member function of `std::weak_ptr<T>`)
expired | checks whether the referenced object was already deleted (public member function of `std::weak_ptr<T>`)
lock | creates a `shared_ptr` that manages the referenced object (public member function of `std::weak_ptr<T>`)
owner_before | provides owner-based ordering of weak pointers (public member function of `std::weak_ptr<T>`)

### Non-member functions

This non-member function is declared in the `std::experimental` namespace, and work with `std::experimental::weak_ptr` rather than std::weak_ptr, but otherwise behaves identically to the corresponding C++14 function.

std::swap(std::weak_ptr) (C++11) | specializes the std::swap algorithm (function template)

### Example

| This section is incomplete Reason: no example

Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/experimental/weak_ptr&oldid=82294"