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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Proposal: Auto-allocation of Indefinite Objects
Date: Mon, 27 Jul 2020 11:49:28 +0200
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On 27/07/2020 11:21, J-P. Rosen wrote:
> Le 27/07/2020 à 09:47, Yannick Moy a écrit :
>>> My proposal is that it should (sometimes?) be possible to declare
>>> objects of indefinite types such as String and have the compiler
>>> automatically declare the space for them without the programmer
>>> having to resort to access types.
>> I agree with the goal.
>>
> You have it already. It's called Unbounded_String.

Not really.

1. Unbounded_String is a compromise needed when the string length change 
during its life. The great majority of cases allocate [and initialize] a 
string just once. [addressed to be the cases when using a discriminant 
does not work]

2. There is nothing for arrays that are not strings and for other 
indefinite types. E.g.:

    type Node_Type is record
       Item : new Element_Type'Class;
       Prev : Node_Ptr_Type;
       Next : Node_Ptr_Type;
    end record;

3. There is nothing for serialization and marshaling objects logically 
containing strings and other indefinite types.

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