TaskCompletionSourceTResult without a type parameter

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TaskCompletionSourceTResult without a type parameter

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#1 by (1 votes)
#2 by (1 votes)

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The TaskCompletionSource<TResult> class needs a TResult type. That way, when I need to use this class without having a return type ( void ), I have to do something like:

var tcs = new TaskCompletionSource<object>();
// ...
tcs.TrySetResult(null);

I do not know if this is the best way to do when the return of a function is only a Task , with no type at all. It seems to me gambiarra.

Is there no TaskCompletionSource without the type parameter? Is there another way out?

c# .net assincronismo task

asked by anonymous 08.11.2017 / 03:20

2 answers

Is it possible to add more than one item to a list at one time? MergeSort, logic problem

score 1 · Answer 1

I'm no expert on this, but I do not think it has a better shape these days. There is no TaskCompletionSource without a result to be defined.

What might be a gain, but I have questions is to return a type by value and not object to avoid allocation in heap . but it will be a very small gain and I do not know if it will generate any consequences elsewhere.

If you want to learn everything about asynchronism and .NET tasks this is the guy to follow .

score 1 · Answer 2

It's by-design . I saw in the SOen that there is a #, written by Stephen Toub, "The Task-based Asynchronous pattern," which reads:

There is no non-generic counterpart to TaskCompletionSource<TResult> . However, Task<TResult> derives from Task , and thus the generic TaskCompletionSource<TResult> can be used for I / O-bound methods that simply return to Task by utilizing a source with a dummy TResult ( bool is a good default choice, and if a developer is concerned about a consumer of the Task downcasting it to Task<TResult> , private TResult type may be used)

There it says to use a boolean in the type, but Stephen Cleary does not recommend, since% w / o% with value% w /% takes the meaning, and a% w / o% w /% w / w% leaves some meaning in value returned. Anyway, matter of semantics.