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From: Robert A Duff <bobduff@world.std.com>
Subject: Re: Using COM Interfaces (was: Releasing Aliased Variables)
Sender: bobduff@world.std.com (Robert A Duff)
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Date: Fri, 9 Mar 2001 17:01:26 GMT
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Date: 2001-03-09T17:01:26+00:00
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Byron Kauffman <byronbkauffman@netscape.net> writes:

> On the other hand, some of the methods defined for the DS objects pass
> pointers to pointers. Would it be a good idea to alias them?

I don't know the answer to your main question, but I can tell you the
Ada rule: if you want to say X'Access, then you must declare X to be
aliased.  If you want to say X'Address, then you *should* declare X to
be aliased.  It is irrelevant whether or not X is itself also a
pointer.

X'Unchecked_Access is like X'Access, except it allows the creation of
dangling pointers.

If you do not want to use any of these three attributes on X, then you
should not declare X to be aliased.

- Bob