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std::promise::get_future(3) C++ Standard Libary std::promise::get_future(3)

NAME

std::promise::get_future - std::promise::get_future

Synopsis


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


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


An exception is thrown if *this has no shared state or get_future has already been
called. To get multiple "pop" ends of the promise-future communication channel, use
std::future::share.


Calls to this function do not introduce data races with calls to set_value,
set_exception, set_value_at_thread_exit, or set_exception_at_thread_exit (therefore
they need not synchronize with each other).

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

2024.06.10 http://cppreference.com