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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Feature suggestion: different task schedules
Date: Sun, 23 Jul 2017 20:47:51 +0200
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Date: 2017-07-23T20:47:51+02:00
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On 2017-07-23 14:31, Victor Porton wrote:
> Dmitry A. Kazakov wrote:
> 
>> One is that it is not composable. I expect a co-routine proposal to
>> offer a possibility to implement stacked layered protocols. I don't see
>> how that would be possible on task basis. A protocol implementation may
>> not be a task object.
> 
> I don't understand why it is not composable. A task may call another tasks.
> Tasks may even call each others in a cycle.

I need to see an example of a layered protocol implemented this way.

> However I think, we may have some sort of problem about specifying something
> in hypothetical Ada2020 what is similar to `yield from` in Python.

I don't see why yield is even needed. In my view it must be a call with 
parameters which would in effect transfer control.

> It seems
> that for this we need to introduce something like "multi" accept statement,
> but I did not yet thought about this.

There is a problem with accept that it contains inversion in itself. 
More natural for a producer-consumer pair is when both make calls, maybe 
to a pseudo protected object, in order to pass control and data. Again I 
must see an example.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de