std::future<T>::share

 

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std::future

future::future

future::~future

future::operator=

future::share

Getting the result

future::get

State

future::valid

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std::shared_future<T> share() noexcept;

Transfers the shared state of *this, if any, to a std::shared_future object. Multiple std::shared_future objects may reference the same shared state, which is not possible with std::future.

After calling share on a std::future, valid() == false.

Parameters

(none)

Return value

A std::shared_future object containing the shared state previously held by *this, if any, constructed as if by std::shared_future<T>(std:move(*this)).

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2556	C++11	share() requires valid() to be true	requirement removed and made noexcept

See also

shared_future (C++11)

waits for a value (possibly referenced by other futures) that is set asynchronously (class template)