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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Does object renaming allow the view to be a copy?
Date: Sun, 22 Jan 2017 17:37:10 +0000
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Date: 2017-01-22T17:37:10+00:00
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AdaMagica <christ-usch.grein@t-online.de> writes:

> Am Sonntag, 22. Januar 2017 09:27:47 UTC+1 schrieb G.B.:
>> A SO answer (41746244) has given rise to the question of whether
>> or not a compiler implementer may make a renamed object a copy
>> of the original. (Layman's assumptions from LRM 3.1(7), 8.5.1),

I did suggest that it would have to be a crazy implementer who did this.

> 3.1(7) ...a renaming_declaration is an example of a declaration that
> does not define a new entity, but instead defines a view of an
> existing entity (see 8.5)...
>
> So how can you think a compiler may create a copy?

I think that if the object isn't limited and the operations done on it
don't alter its contents you'd be hard put to it to tell the difference,
that's all.

But like I said, crazy. Under the hood, any sensible person would have a
reference to the original object.