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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Ada package registry?
Date: Tue, 9 Feb 2016 09:50:56 +0100
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Date: 2016-02-09T09:50:56+01:00
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On 09/02/2016 00:02, Randy Brukardt wrote:
> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
> news:n94cbv$19ed$1@gioia.aioe.org...

>> 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.
>
> The first is the function call (to Reference, if you're looking at the Ada
> containers), and the second is the Finalize call that happens when the
> object returned from Reference goes away. That was the whole point of the
> design. (Of course, you could have written that in Ada 95, but without the
> syntactic sugar that makes it easier to read and write.)

It is not same. A reference points to a proxy object, a cached copy of 
the external object in the persistent storage. When the proxy object is 
updated via any reference, it must be marked dirty. So that when the 
object at some point gets finalized or the transaction is committed it 
would be written back to the storage.

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