std::experimental::weak_ptr

C++

Language

Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

Technical specifications

Filesystem library (filesystem TS)

Library fundamentals (library fundamentals TS)

Library fundamentals 2 (library fundamentals 2 TS)

Extensions for parallelism (parallelism TS)

Extensions for parallelism 2 (parallelism TS v2)

Extensions for concurrency (concurrency TS)

Concepts (concepts TS)

Ranges (ranges TS)

Special mathematical functions (special math TR)

Library fundamentals

experimental::optional

experimental::any

experimental::basic_string_view

experimental::sample

experimental::shared_ptr

experimental::weak_ptr

experimental::apply

experimental::invocation_type experimental::raw_invocation_type

experimental::search

experimental::default_searcher experimental::make_default_searcher

experimental::boyer_moore_searcher experimental::make_boyer_moore_searcher

experimental::boyer_moore_horspool_searcher experimental::make_boyer_moore_horspool_searcher

type-erased and polymorphic allocators

variable templates for type traits

std::experimental::weak_ptr

weak_ptr::weak_ptr

Members and non-members identical to those of std::weak_ptr

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)
operator=	assigns the weak_ptr (public member function of std::weak_ptr)
Modifiers
reset	releases the ownership of the managed object (public member function of std::weak_ptr)
swap	swaps the managed objects (public member function of std::weak_ptr)
Observers
use_count	returns the number of shared_ptr objects that manage the object (public member function of std::weak_ptr)
expired	checks whether the referenced object was already deleted (public member function of std::weak_ptr)
lock	creates a shared_ptr that manages the referenced object (public member function of std::weak_ptr)
owner_before	provides owner-based ordering of weak pointers (public member function of std::weak_ptr)

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)