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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: put of access type
Date: Wed, 19 Aug 2009 17:45:24 -0500
Organization: Jacob Sparre Andersen
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Date: 2009-08-19T17:45:24-05:00
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"Adam Beneschan" <adam@irvine.com> wrote in message 
news:c9aec6d6-4e9b-4bf6-9586-68a237175c9d@i18g2000pro.googlegroups.com...
...
>Also, there's no rule saying that an access value has to be an address
>at all.  It's certainly conceivable that an access value may be
>implemented as a reference to some storage pool and an offset into
>that pool, allowing for the possibility that the memory management
>system may just decide to pick up the whole pool and move it to some
>other address, without making any of the access values invalid.

I think the Ada 95 definition of storage pools would make this 
implementation hard to make work. (Which is unfortunate, it would have 
worked fine in Ada 83).

I've been looking at ways to change this (a storage pool that returns 
persistent handles for access values ought to be possible), but I'm not 
completely certain that it is worth the effort.

                              Randy.