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Defined in header <experimental/memory>
template< class W >
class observer_ptr;
(library fundamentals TS v2)

std::experimental::observer_ptr is a non-owning pointer, or observer. The observer stores a pointer to a second object, known as the watched object. An observer_ptr may also have no watched object.

An observer is not responsible in any way for the watched object; there is no inherent relationship between an observer and the object it watches.

It is intended as a near drop-in replacement for raw pointer types, with the advantage that, as a vocabulary type, it indicates its intended use without need for detailed analysis by code readers.

Specializations of observer_ptr satisfy the requirements of CopyConstructible and CopyAssignable.

Type requirements
W shall not be a reference type, but may be an incomplete type.


[edit] Member types

Member type Definition
element_type W, the type of the object watched by this observer_ptr

[edit] Member functions

constructs a new observer_ptr
(public member function) [edit]
(implicitly declared)
destructs an observer_ptr
(public member function) [edit]
(implicitly declared)
implicitly declared copy and move assignment operators that assign the stored pointer
(public member function) [edit]
returns a pointer to the watched object and stops watching the object
(public member function) [edit]
replaces the watched object
(public member function) [edit]
swaps the watched objects
(public member function) [edit]
returns a pointer to the watched object
(public member function) [edit]
checks if there is an associated watched object
(public member function) [edit]
dereferences pointer to the watched object
(public member function) [edit]
explicit conversion function to the stored pointer
(public member function) [edit]

[edit] Non-member functions

creates an observer_ptr that watches an object
(function template) [edit]
compares to another observer_ptr or with nullptr
(function template) [edit]
specializes the swap algorithm
(function template) [edit]

[edit] Helper classes

hash support for observer_ptr
(class template specialization) [edit]

[edit] Example