future_fwd.hpp#

Defined in header hpx/futures/future_fwd.hpp.

See Public API for a list of names and headers that are part of the public HPX API.

namespace hpx

Top level HPX namespace.

template<typename R> class future

#include <future_fwd.hpp>

The class template hpx::future provides a mechanism to access the result of asynchronous operations:

An asynchronous operation (created via hpx::async, hpx::packaged_task, or hpx::promise) can provide a hpx::future object to the creator of that asynchronous operation.
The creator of the asynchronous operation can then use a variety of methods to query, wait for, or extract a value from the hpx::future. These methods may block if the asynchronous operation has not yet provided a value.
When the asynchronous operation is ready to send a result to the creator, it can do so by modifying shared state (e.g. hpx::promise::set_value) that is linked to the creator’s hpx::future. Note that hpx::future references shared state that is not shared with any other asynchronous return objects (as opposed to hpx::shared_future).

template<typename R> class promise : public hpx::detail::promise_base<R>#: #include <promise.hpp>

template<typename R> class shared_future: #include <future_fwd.hpp>

The class template hpx::shared_future provides a mechanism to access the result of asynchronous operations, similar to hpx::future, except that multiple threads are allowed to wait for the same shared state. Unlike hpx::future, which is only moveable (so only one instance can refer to any particular asynchronous result), hpx::shared_future is copyable and multiple shared future objects may refer to the same shared state. Access to the same shared state from multiple threads is safe if each thread does it through its own copy of a shared_future object.