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From: hreba <f_hreba@yahoo.com.br>
Newsgroups: comp.lang.ada
Subject: Re: storage error: stack overflow
Date: Tue, 18 Aug 2015 22:48:48 -0300
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Xref: news.eternal-september.org comp.lang.ada:27500
Date: 2015-08-18T22:48:48-03:00
List-Id: <comp.lang.ada>

On 08/18/2015 11:16 AM, Jeffrey R. Carter wrote:
> On 08/18/2015 07:02 AM, hreba wrote:
>>
>> Huh? As much as I know you cannot declare variables of a type with unknown
>> storage requirements at compile time, such as class-wide types and arrays with
>> unknown range.
>
> These are "indefinite types". You can declare an object of an indefinite type as
> long as you supply an initialization expression:
>
> S : String := "Hello";
>
> V : T'Class := Some_Function;
>

If the object is initialized, the storage requirement is known at 
compile type. My situation is a typical object orientation case as shown 
in a lot of examples where you have a (possibly abstract) base type and 
several extensions and where the dynamic type of a variable is not known 
at compile time. Classic example would be an inhomogeneous list (I know 
in practice you use a container for that, it is just an example).
My knowledge of Ada exceeds Ada 95 only by very little but I am pretty 
sure that in such a case one uses variables of a class-wide type, and as 
one cannot initialize them one has to declare them as access types.

Or, if I am wrong, what would be the best practice for that?
-- 
Frank Hrebabetzky		+55 / 48 / 3235 1106
Florianopolis, Brazil