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Questions tagged [task]

A task is an abstraction that is used to work with concurrency, it can denote operation that should be executed concurrently with the rest of a program. A task is a concurrent thread of execution in Ada and represents an asynchronous operation in .NET, also it corresponds to Threads in Java.

A task is an abstraction that is used to work with concurrency, it can denote operation that should be executed concurrently with the rest of a program.

  • Ada
    A task is a concurrent thread of execution in an Ada program. Task definitions are split into two parts - declaration and a body, which is mandatory. Task declaration defines entities exported from the task, whereas its body contains local declarations and statements of the task.

  • .NET
    Task is used to represents an asynchronous operation, it is a core concept of the which is used for asynchronous and parallel programming in the .NET framework.

  • C++
    future is used to represent an operation which may complete some time in the future. It helps programs achieve a degree of asynchrony where they may want/need to perform certain operations in parallel. std::async creates a task which may execute asynchronously, returning a std::future.

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Await on a completed task same as task.Result?

I'm currently reading "Concurrency in C# Cookbook" by Stephen Cleary, and I noticed the following technique: var completedTask = await Task.WhenAny(downloadTask, timeoutTask); if (completedTask == timeoutTask) return null; return await…
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How can I call an async method in Main?

public class test { public async Task Go() { await PrintAnswerToLife(); Console.WriteLine("done"); } public async Task PrintAnswerToLife() { int answer = await GetAnswerToLife(); …
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How do I enable TODO/FIXME/XXX task tags in Eclipse?

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Await vs Task.Result in an Async Method

What's the difference between doing the following: async Task method(){ var r = await dynamodb.GetItemAsync(...) return r.Item; } vs async Task method(){ var task = dynamodb.GetItemAsync(...) return task.Result.Item; } In my…
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Task.Run with Parameter(s)?

I have implemented a simple Task.Factory.StartNew() and I wonder how can I do it with Task.Run() instead? Here is the basic code: Task.Factory.StartNew(new Action( (x) => { // Do something with 'x' }), rawData); I looked into…
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A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was

What does this mean and how to resolve it? I am using TPL tasks. The whole error A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the…
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Timer & TimerTask versus Thread + sleep in Java

I found similar questions asked here but there weren't answers to my satisfaction. So rephrasing the question again- I have a task that needs to be done on a periodic basis (say 1 minute intervals). What is advantage of using Timertask & Timer to do…
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Difference between OperationCanceledException and TaskCanceledException?

What is the difference between OperationCanceledException and TaskCanceledException? If I am using .NET 4.5 and using the async/await keywords, which one should I be looking to catch?
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Platform.runLater and Task in JavaFX

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Promise equivalent in C#

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How to properly create and run concurrent tasks using python's asyncio module?

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My C# application is returning 0xE0434352 to Windows Task Scheduler but it is not crashing

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Why is Task not co-variant?

class ResultBase {} class Result : ResultBase {} Task GetResult() { return Task.FromResult(new Result()); } The compiler tells me that it cannot implicitly convert Task to Task. Can someone explain why this is?…
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What is the best way to seed a database in Rails?

I have a rake task that populates some initial data in my rails app. For example, countries, states, mobile carriers, etc. The way I have it set up now, is I have a bunch of create statements in files in /db/fixtures and a rake task that processes…
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What is the 'realtime' process priority setting for?

From what I've read in the past, you're encouraged not to change the priority of your Windows applications programmatically, and if you do, you should never change them to 'Realtime'. What does the 'Realtime' process priority setting do, compared to…
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