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From: dennison@telepath.com (Ted Dennison)
Newsgroups: comp.lang.ada
Subject: Re: Behavior of Stream Attributes On Access Types.
Date: 11 Jun 2002 06:47:46 -0700
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"Marin David Condic" <dont.bother.mcondic.auntie.spam@[acm.org> wrote in message news:<ae2v7f$r12$1@nh.pace.co.uk>...
> My inclination is to think that the sensible thing would be to call the
> 'Read or 'Write for the thing pointed to by the access type, but this has

You can pretty much count on it *not* doing that. For instance, what
would happen in that case with a circularly-referenced structure like
a doubly-linked list?


> implications for dynamically allocated objects. Will it write/read a
> (totally useless) access value?

Pretty much. It isn't *totally* useless. It will work just fine within
the same execution (assuming you don't deallocate the memory).
However, it is next to useless.

If you want better behavior, its up to you to override 'Write and
'Read for your pointer type. Then you can code it to handle things
like circular references and deallocating the target's old value on a
'Read.


-- 
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