Introduction to std::shared_future

std::shared_future #

A future becomes shared by using fut.share(). A shared future is associated with its promise and can independently ask for the result. An std::shared future has the same interface as an std::future.

In addition to the std::future, a std::shared_future enables us to query the promise independently of the other associated futures.

There are two ways to create a std::shared_future:

1. Invoke fut.share() on an std::future fut. Afterwards, the result is no longer available. That means valid == false.
2. Initialize an std::shared_future from an std::promise: std::shared_future<int> divResult= divPromise.get_future().

The handling of an std::shared_future is special.