std::promise::get_future

 

C++

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Thread support library

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thread (C++11)
this_thread namespace
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promise (C++11) future (C++11) shared_future (C++11) packaged_task (C++11) async (C++11)	launch (C++11) future_status (C++11) future_error (C++11) future_category (C++11) future_errc (C++11)

 

std::promise

Member functions

promise::promise

promise::~promise

promise::operator=

promise::swap

Getting the result

promise::get_future

Setting the result

promise::set_value

promise::set_value_at_thread_exit

promise::set_exception

promise::set_exception_at_thread_exit

 

std::future<R> get_future();		(since C++11)

Returns a future object associated with the same shared state as *this.

Exception is thrown if *this has no shared state or get_future has already been called.

Parameters

(none)

Return value

A future referring to the shared state of *this

Exceptions

std::future_error on the following conditions:

• *this has no shared state. The error category is set to no_state.

• get_future() has already been called on a promise with the same shared state as *this. The error category is set to future_already_retrieved.