asyncio.as_completed() takes an iterable of coroutines or futures and returns an iterable of futures in the order that the input futures complete. Normally, you’d loop over its result and await the members from inside an async function… import asyncio async def first(): await asyncio.sleep(5) return ‘first’ async def second(): await asyncio.sleep(1) return ‘second’ async def … Read more
sort does not take an asynchronous callback. It expects a numeric value as the return value, not a promise for one; and it does return an array not a promise. There’s no way around this (though one could implement a custom asynchronous sorting algorithm – even a parallel one). But that’s pretty inefficient anyway. Doing … Read more
I found the following suggestion on a Microsoft github repository: How to await a UI task sent from a background thread. Setup Define this extension method for the CoreDispatcher: using System; using System.Threading.Tasks; using Windows.UI.Core; public static class DispatcherTaskExtensions { public static async Task<T> RunTaskAsync<T>(this CoreDispatcher dispatcher, Func<Task<T>> func, CoreDispatcherPriority priority = CoreDispatcherPriority.Normal) { var … Read more
daryal provided the answer here http://smellegantcode.wordpress.com/2012/08/28/a-boring-discovery/ It seems ReadLineAsync is not actually doing what it’s supposed to do. Bug in the framework. My solution is to use ThreadPool.QueueUserWorkItem in a loop so each call to ReadLineAsync is done on a new thread.
You can use an IIFE here (Read more about it here) (async function main () { // You can use await inside this function block })();
Let’s make sure to not bury the lede here: So for example: [some correct code] becomes [some incorrect code] NEVER NEVER NEVER DO THIS. Your instinct that you can restructure your control flow to improve performance is excellent and correct. Using Result to do so is WRONG WRONG WRONG. The correct way to rewrite your … Read more
This is going to be a bit long. First of all, thanks Matt Smith and Hans Passant for your ideas, they have been very helpful. The problem was caused by a good old friend, Application.DoEvents, although in a novelty way. Hans has an excellent post about why DoEvents is an evil. Unfortunately, I’m unable to … Read more
I want to do Asynchronous I/O calls (using async await) – but : Without using DataFlow dependency ( like in this answer) Without middle buffers( not like this answer) The Projector function should be sent as an argument. ( not like this answer) You may want to check Stephen Toub’s “Tasks, Monads, and LINQ” for … Read more
High Level – Are async/await the best choice, or should I use a different approach? async-await is perfect for what you’re attempting to do, which is concurrently offloading multiple IO bound tasks. What needs to be updated to allow the loop to kick off all the jobs without blocking, but not allow the function to … Read more
Am I correct that It does guarantee your continuations will get the same HttpContext.Current as original callers? It does not guarantee the continuations will execute on the same thread as the callers? Yes, HttpContext.Current is preserved, and yes, the continuations may execute on a different thread. I mean principal/culture associated with the thread and thread … Read more