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From: Georg Bauhaus <nonlegitur@futureapps.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Why doesn't Ada allow user-defined attributes?
Date: Fri, 21 Jul 2017 04:46:04 -0000 (UTC)
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Date: 2017-07-21T04:46:04+00:00
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Shark8 <onewingedshark@gmail.com> wrote:
> On Thursday, July 20, 2017 at 3:38:52 AM UTC-6, Brian Drummond wrote:
>> 
>> Offhand I'm not sure I can see similar purposes for extending Ada's 
>> attributes. 
>> 
>> Got any use cases in mind?
> 
> Yes; several.
> 
> 
> Second, and more intimidate, would be allowing Ada.Containers to
> implement a full Array interface, where appropriate. (e.g. having
> Vector'Length and Vector'Range; this consistency of interface will be
> nice as then you wouldn't have to remember "I'm using a vector, I have to
> use V.Length *not* V'Length.")
> 

Do you really need 'Length?
It seems an implementation detail whenever the language doesn't have forall
or exists.
So, I'd rather want to use arrays with the generalized iteration scheme.
(Granted, I don't need to write Binary Search etc.)