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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Garbage Collection ???
Date: Fri, 20 Apr 2012 19:46:32 -0500
Organization: Jacob Sparre Andersen Research & Innovation
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Date: 2012-04-20T19:46:32-05:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message 
news:itjg3eh0o4s8.rm273bcoi1tb$.dlg@40tude.net...
> On Thu, 19 Apr 2012 15:26:03 -0500, Randy Brukardt wrote:
...
>> Null-exclusions are
>> almost exclusively useful for parameters, where you don't need "nothing"
>> simply because you don't make the call in that case.)
>
> and access discriminants, certainly.
>
> However both cases do not feel good. I mean why there should be a pointer?
> Is it always a reference semantics? Frequently it is not. But even if the
> semantics is indeed referential, why explicit pointer?

I agree in general. Especially for Ada 2012, where you can used "aliased" to 
make any parameter of any type pass-by-reference.

The usual reason to pass a pointer is that you already have one for some 
other reason. That's typical in data structures, for instance (remember that 
Ada.Containers has Cursor, which is just like an access type except isn't 
one explicitly).

                                     Randy.