Python and JavaScript don’t do CPU threads (well, Python can do threads, but that’s not relevant here, because Python’s thread stuff isn’t inherently await-able). So they fake threading with “event loops”. C++ is a low-level language that knows what CPU threads are and expects to make use of them. As such, when you co_await on … Read more
You can create your own CoroutineScope with a SupervisorJob that you can cancel in the onDestroy() method. The coroutines created with this scope will live as long as your Service is being used. Once onDestroy() of your service is called, all coroutines started with this scope will be cancelled. class YourService : Service() { private … Read more
Syntax for python >=3.5 loop = asyncio.get_event_loop() for signame in (‘SIGINT’, ‘SIGTERM’): loop.add_signal_handler(getattr(signal, signame), lambda: asyncio.ensure_future(ask_exit(signame)))
Let’s consider how to apply two aggregate functions to the same iterator, which we can only exhaust once. The initial attempt (which hardcodes sum and max for brevity, but is trivially generalizable to an arbitrary number of aggregate functions) might look like this: def max_and_sum_buffer(it): content = list(it) p = sum(content) m = max(content) return … Read more
val one = async { one() } val two = async { two() } val int1 = one.await() val int2 = two.await() What this does: spawn task one spawn task two await on task one await on task two val one = async { one() }.await() val two = async { two() }.await() What this … Read more
I’ve found out that it’s because of a CoroutineDispatcher. I used to mock UI context with EmptyCoroutineContext. Switching to Unconfined has solved the problem Update 02.04.20 The name of the question suggests that there’ll be an exhaustive explanation how to unit test a suspending function. So let me explain a bit more. The main problem … Read more
N4775 outlines the proposal for coroutines for C++20. It introduces an number of different ideas. The following is from my blog at https://dwcomputersolutions.net . More info can be found in my other posts. Before we examine our whole Hello World coroutine program, go through the various parts step-by-step. These include: The coroutine Promise The coroutine … Read more
Closing a channel conceptually works by sending a special “close token” over this channel. You close a channel when you have a finite sequence of elements to be processed by consumers and you must signal to the consumers that this sequence is over. You don’t have to close a channel otherwise. Channels are not tied … Read more