Dealing with unhandled rejected native promises (and async/await uses native promises) is a feature supported now in V8. It’s used in the latest Chrome to output debugging information when a rejected promise is unhandled; try the following at the Babel REPL: async function executor() { console.log(“execute”); } async function doStuff() { console.log(“do stuff”); throw new … Read more
Transforming the result of await ends up being annoying in terms of precedence I generally prefer to introduce a local var, but as you noted, that prevents expression-bodied methods. We occasionally forget ConfigureAwait(false) – this is solvable with tooling to some extent Since you’re working on a library and should use ConfigureAwait(false) everywhere, it may … Read more
How interesting! It appears that Thread.CurrentPrincipal is based on the logical call context, not the per-thread call context. IMO this is quite unintuitive and I’d be curious to hear why it was implemented this way. In .NET 4.5., async methods interact with the logical call context so that it will more properly flow with async … Read more
No can do. When someone expects a Func<T> f you can assume it will be invoked with something like result = f() – i.e., it does not know about async behavior. If you cheat it by using .Result like you have, it will deadlock on UI thread because it wants to schedule the code after … Read more
You are calling the same func parameter twice: var response = await ProcessRequestAsync(func); //… response = await ProcessRequestAsync(func); In this case func returns the same request every single time. It doesn’t generate a new one every time you call it. If you truly need a different request each time then func needs to return a … Read more
No, co-routines do not involve any kind of threads. Co-routines allow for cooperative multi-tasking in that each co-routine yields control voluntarily. Threads on the other hand switch between units at arbitrary points. Up to Python 3.4, it was possible to write co-routines using generators; by using yield or yield from expressions in a function body … Read more
You could use CallContext.LogicalSetData and CallContext.LogicalGetData, but I recommend you don’t because they don’t support any kind of “cloning” when you use simple parallelism (Task.WhenAny / Task.WhenAll). I opened a UserVoice request for a more complete async-compatible “context”, explained in more detail in an MSDN forum post. It does not seem possible to build one … Read more
I disagree with Ricka on this. Async DB commands are not only good, they are critical in achieving scale, throughput and latency. His objection about the ramp up time of the thread pool applies only to a web server that experiences low traffic volumes. In a high traffic situation (which is the only one that … Read more
It is unfortunate that this doesn’t work and we will see about getting a fix out in a future release. In the mean time, there is a way to reapply the context to the current thread so that you don’t have to pass the object around: public async Task<double> Add(double n1, double n2) { OperationContext … Read more
The async equivalent is a while loop with Task.Delay (which internally uses a System.Threading.Timer): public async Task PeriodicFooAsync(TimeSpan interval, CancellationToken cancellationToken) { while (true) { await FooAsync(); await Task.Delay(interval, cancellationToken) } } It’s important to pass a CancellationToken so you can stop that operation when you want (e.g. when you shut down your application). Now, … Read more