ALBANY, N.Y. (NEWS10) — The State of the Capital District Transportation Authority address was held on Wednesday. CEO Frank Annicaro outlined the CDTA’s accomplishments and future plans in the address ...
An asynchronous operation (created via std::async, std::packaged_task, or std::promise) can provide a std::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 std::future.
The function template std::async runs the function f asynchronously (potentially in a separate thread which might be a part of a thread pool) and returns a std::future that will eventually hold the result of that function call.
C++ includes built-in support for threads, atomic operations, mutual exclusion, condition variables, and futures.
The code above might look ugly, but all you have to understand is that the FutureBuilder widget takes two arguments: future and builder, future is just the future you want to use, while builder is a function that takes two parameters and returns a widget. FutureBuilder will run this function before and after the future completes.
Checks if the future refers to a shared state. This is the case only for futures that were not default-constructed or moved from (i.e. returned by std::promise::get_future (), std::packaged_task::get_future () or std::async ()) until the first time get () or share () is called. The behavior is undefined if any member function other than the destructor, the move-assignment operator, or valid is ...
The class template std::packaged_task wraps any Callable target (function, lambda expression, bind expression, or another function object) so that it can be invoked asynchronously. Its return value or exception thrown is stored in a shared state which can be accessed through std::future objects.
The error: SyntaxError: future feature annotations is not defined usually related to an old version of python, but my remote server has Python3.9 and to verify it - I also added it in my inventory and I printed the ansible_facts to make sure.
If the future is the result of a call to std::async that used lazy evaluation, this function returns immediately without waiting. This function may block for longer than timeout_duration due to scheduling or resource contention delays. The standard recommends that a steady clock is used to measure the duration.