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From: "Alejandro R. Mosteo" <alejandro@mosteo.com>
Newsgroups: comp.lang.ada
Subject: Re: 'Class'Class'Class'Class ad libitum
Date: Tue, 13 Sep 2016 18:10:43 +0200
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Date: 2016-09-13T18:10:43+02:00
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On 13/09/16 13:29, J-P. Rosen wrote:
> Le 13/09/2016 à 12:43, Alejandro R. Mosteo a écrit :
>> I get why this is legal:
>>
>>    type X is tagged null record;
>>
>>    subtype Y is X'Class;
>>
>>    subtype Z is X'Class'Class'Class'Class;
>>
>> But can you think of any legitimate reason to use it besides obfuscation?
>>
> I guess this is allowed because nobody cared about complicated rules to
> forbid it (mainly on the ground that it's useless, but harmless). There
> are many things like that:
>   T'(T'(T'(X)))
>   X+0+0+0
>   ...

I like the qualified expression one...