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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: A bad counterintuitive behaviour of Ada about OO
Date: Thu, 7 Aug 2014 18:10:57 +0200
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Date: 2014-08-07T18:10:57+02:00
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On Thu, 07 Aug 2014 15:34:26 +0200, J-P. Rosen wrote:

> Le 07/08/2014 14:28, Dmitry A. Kazakov a écrit :
>>> No doubt? I'm very happy that elementary types are kept separate from
>>> > all the OO stuff, for example...
>> Is it OO being able to write a class-wide numeric Sort, Put, Image,
>> container?
> I prefer generics for that kind of stuff. It keeps my types independent,
> and it doesn't need any dispatching.

Generics do not work for containers: you cannot have one of class-wide
elements. And generics enforce overloading which is a bad idea as
Ada.Text_IO has proven.

>> Anyway, it would help to indicate reasons for this happiness. I see no gain
>> in having types and not-quite types in the language. And there are lot of
>> problems with not-quite types in Ada concerning safety, reuse,
>> maintainability (Ada's key features, BTW).
> 
> Because good ol' elementary types are much simpler to understand, and
> more efficient to implement.

Having classes of elementary types does not change anything.

> Classification makes sense only if you have
> heterogeneous data structures that manipulate various types belonging to
> a same class. This is rarely the case for elementary types.

It is in any math book. Fields, groups, rings, spaces are such
classifications known for centuries.

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