std::shared_future<T>::get

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std::shared_future

Member functions
shared_future::shared_future
shared_future::~shared_future
shared_future::operator=
Getting the result
shared_future::get
State
shared_future::valid
shared_future::wait
shared_future::wait_for
shared_future::wait_until

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Main template
const T& get()const;	(1)	(since C++11)
std::shared_future<T&> specializations
T& get()const;	(2)	(since C++11)
std::shared_future<void> specialization
void get()const;	(3)	(since C++11)

Theget member function waits (by callingwait()) until the shared state is ready, then retrieves the value stored in the shared state (if any).

Ifvalid() isfalse before the call to this function, the behavior is undefined.

[edit]Return value

1) A const reference to the value stored in the shared state. The behavior of accessing the value through this reference after the shared state has been destroyed is undefined.

2) The reference stored as value in the shared state.

3) (none)

[edit]Exceptions

If an exception was stored in the shared state referenced by the future (e.g. via a call tostd::promise::set_exception()) then that exception will be thrown.

[edit]Notes

The C++ standard recommends the implementations to detect the case whenvalid() isfalse before the call and throw astd::future_error with an error condition ofstd::future_errc::no_state.