Infer return type for non-generic async method builder from SetResult

[sharwell]

Currently a task-like type with a non-generic AsyncMethodBuilder requires the SetResult method to not take an argument (the asynchronous equivalent of a void method). It would be helpful if the effective return type for such a case was inferred from the argument, if any, accepted by the SetResult method. For example, suppose you had the following:

[AsyncMethodBuilder(typeof(IntTaskMethodBuilder))]
public struct IntTask {
  // ...
}

public struct IntTaskMethodBuilder {
  // ...

  public void SetResult(int result) // <-- if this was allowed
  {
  }
}

// Then we could do this:
public async IntTask MethodAsync()
{
  return 1;
}

[paulomorgado]

@sharwell, I understand what you're asking for and it can be done. But, what's your motivation for this?

Would multiple overloads of SetResult allow the task method builder to be reusable across multiple task-like types?

[sharwell]

@paulomorgado it came up during an experiment I'm working on. Right now it's so early that I can't say for sure whether or not I would use this. I have a working prototype, but haven't put it into practice enough to see how it holds up.

Would multiple overloads of SetResult allow the task method builder to be reusable across multiple task-like types?

This seems lower priority but reasonable.