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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Timeouts in Ada
Date: Thu, 17 Jul 2014 13:52:41 -0700
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Xref: news.eternal-september.org comp.lang.ada:21025
Date: 2014-07-17T13:52:41-07:00
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On 07/17/2014 12:51 PM, J-P. Rosen wrote:
>>
> Did you check this with an implementation? For one thing, Current_Task must
> be the same in the abortable part and in the trigger...

And Adam Beneschan wrote:

> Not quite.  If the <trigger> is an entry call, and the entry can be selected
> immediately, the <abortable part> never starts (unless the entry is
> requeued-with-abort); your code would have the <abortable part> start, and
> then get aborted when the entry call is completed.
>
> If the trigger is an entry call and the entry is queued, *then* the abortable
> part is aborted when the entry call completes, not when it's selected.
>
> There are other cases where the language says the abortable part would never
> start, but in your code above, it's nondeterministic whether your abortable
> part would start or not.

"Shorthand", of course, was shorthand for "roughly equivalent to", or maybe 
"intended to be better than ..., which is what people did in Ada 83".

-- 
Jeff Carter
"You a big nose have it."
Never Give a Sucker an Even Break
107