Update FS-1097-task-builder.md

[dsyme]

Update spec of backgroundTask { ... }, based on rspeele/TaskBuilder.fs#35 (comment)

[NinoFloris]

I think it shouldn't do this, backgroundTask screams 'everything inside of this will not run on this thread' yet a single while true at the start would now halt my thread. A context insenstive builder would serve as a better option if we want that mixed mode behavior IMO.

Even if we'd decide to keep this new semantics just checking SyncCtx is not enough. Tasks also respect TaskScheduler.Current meaning we must include another check to see if it's anything but TaskScheduler.Default.

[dsyme]

@NinoFloris Thanks for this.

Let's discuss on the discussion thread

[smoothdeveloper]

@dsyme, AFAIR, this is a split of a larger RFC, but it still points to the larger RFC and I think the semantics of task from end user point of view don't depend on the compiler machinery of the larger RFC.

Would it make sense to have a separate new discussion thread on just task CE?

[dsyme]

Would it make sense to have a separate new discussion thread on just task CE?

It would