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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Not null feature with anonymous and named access types
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Date: Tue, 13 Jun 2006 09:53:41 +0200
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Date: 2006-06-13T09:53:33+02:00
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On 12 Jun 2006 16:13:34 -0700, Anh Vo wrote:

> Bj�rn Persson wrote:
>> Anh Vo wrote:
>>> I have been exploring the not null feature with anonymous access type
>>> and named access type. One thing have learned that an access variable
>>> declared based on these types will raise a Constraint_Error when
>>> deallocating this access variable as shown in the code below.
>>
>> Of course. Deallocation sets the access variable to null, and that
>> violates the not-null constraint.
>>
> Thanks for your quick reply.
> 
> Based on this requirement, one should not use not null access in this
> case due to memory leak as the result of memory deallocation
> incapability.

Often memory management and handling objects should be well separated. In
public interfaces, where pointers are needed, null access types can be very
useful. This by no means should prevent the implementation interfaces from
using plain pointers, arena allocators, garbage collectors, etc to manage
memory.

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