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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Ada package registry?
Date: Sat, 6 Feb 2016 09:54:09 +0100
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Date: 2016-02-06T09:54:09+01:00
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On 2016-02-06 01:04, Randy Brukardt wrote:
> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
> news:n91oau$1bk5$1@gioia.aioe.org...
>> On 04/02/2016 22:09, Randy Brukardt wrote:
> ....
>>> (The reason that we adopted the generalized reference feature that we did
>>> is
>>> because of the ability to use it to manage persistence -- in particular,
>>> to
>>> be able to figure out when the in-memory copy can be freed and written to
>>> the backing store.)
>>
>> That is not enough. You need references with a notification upon
>> dereferencing.
>
> That's called "a function call" :-). There's no need for a separate feature
> for that (since anonymous access results are essentially uncopyable). What
> was missing was a way to know when the access itself goes away.

That is called a function call too.

For persistence layer you need dereference primitive operations. One for 
read access in order to cache data and one write access to mark the 
cache dirty.

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