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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Pop function
Date: Thu, 15 Dec 2011 21:15:44 +0100
Organization: cbb software GmbH
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Date: 2011-12-15T21:15:44+01:00
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On Thu, 15 Dec 2011 12:57:47 -0700, Jeffrey Carter wrote:

> On 12/15/2011 01:38 AM, Dmitry A. Kazakov wrote:
>> On Wed, 14 Dec 2011 17:34:57 -0700, Jeffrey Carter wrote:
>>
>>> Your public interface should never use access types.
>>
>> Yes, but since list as a data structure has the semantics of objects
>> accessed by references it would make sense to have this reflected in the
>> interface. But of course the list element must be
>>
>>     type List_Item is access Integer; -- Only the data, no other mess
> 
> No, a public interface should never use access types, ever. Hiding those is what 
> abstraction is about. Any public interface that uses access types is poorly 
> designed.

In that case there should be no linked lists at all. A linked list is per
its definition a set of elements accessed using pointers.

It is possible that the OP wanted something else, but that is another
question.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de