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From: Jacob Sparre Andersen <sparre@nbi.dk>
Newsgroups: comp.lang.ada
Subject: Re: Task with access to itself?
Date: Tue, 11 Dec 2012 12:21:06 +0100
Organization: Jacob Sparre Andersen Research & Innovation
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Date: 2012-12-11T12:21:06+01:00
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Jeffrey Carter wrote:

> We make extensive use of a similar pattern, but rather than having the
> tasks register their availability and be given work to do, we have the
> tasks get their work from a protected queue. The task body tends to
> look like
>
> Forever : loop
>    exit Forever when Finalization.Control.Finalizing; -- Protected function
>
>    select
>       Work_Queue.Get (Item => Work_Item);
>       -- Blocks until something is on the queue
>       Process (Job_Info => Work_Item);
>    or
>       delay ...;
>    end select;
> end loop Forever;

This is a nice pattern, but it lacks two features I would like to have:

 1) Dynamic addition of tasks.
 2) Control over which order the worker tasks are activated in.

Point 2 can of course be managed with an appropriate
modification/addition to the run-time system.

Greetings,

Jacob
-- 
"The current state of knowledge can be summarised thus:
 In the beginning, there was nothing, which exploded."