Mar 12, 2024 · The class template std::future provides a mechanism to access the result of asynchronous operations: An asynchronous operation (created via std::async, std::packaged_task, …

Aug 2, 2020 · wait_until waits for a result to become available. It blocks until specified timeout_time has been reached or the result becomes available, whichever comes first. The return value indicates why …

Oct 22, 2023 · 2) Move constructor. Constructs a std::future with the shared state of other using move semantics. After construction, other.valid() == false.

Feb 22, 2024 · The get member function waits (by calling wait ()) until the shared state is ready, then retrieves the value stored in the shared state (if any). Right after calling this function, valid () is false. …

Nov 27, 2023 · future (const future &) = delete; ~future (); future & operator =(const future &) = delete; future & operator =(future &&) noexcept; shared_future <R> share () noexcept; // retrieving the value …

Jul 8, 2025 · 1. If a future's task has not already started then cancelling the future will prevent the task from ever starting, regardless of whether true or false was passed to cancel. 2. Cancelling an already …

Oct 23, 2023 · Unlike std::future, which is only moveable (so only one instance can refer to any particular asynchronous result), std::shared_future is copyable and multiple shared future objects …

Oct 23, 2023 · The promise is the "push" end of the promise-future communication channel: the operation that stores a value in the shared state synchronizes-with (as defined in std::memory_order) …

Mar 6, 2020 · impl<F> Future for Box<F> where F: Unpin + Future + ?Sized, Boxed futures only implement the Future trait when the future inside the Box implements Unpin. Since your function …

Jan 12, 2023 · One plausible scenario is existence of another future grants that are assigned on schema level to different role. In such situation future grants assigned on the database level are ignored. …