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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Extend slices for n dimensional arrays for Ada 202X
Date: Fri, 27 Jan 2017 15:20:04 +0100
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Date: 2017-01-27T15:20:04+01:00
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On 27/01/2017 14:53, G.B. wrote:
> On 27.01.17 10:34, Dmitry A. Kazakov wrote:
>> On 26/01/2017 19:29, Randy Brukardt wrote:
>>
>>> So I don't see this happening - it doesn't make sense in the context
>>> of Ada
>>> implementation strategies.
>>
>> That is why I keep on saying, give users the array interface (and the
>> array slice interface) and let users implement their custom arrays.
>
> Will some Iterator_Interface and generalized
> loop iteration not provide for custom arrays?

Not even close. Remember the question was about slices. A slice in 
copying context is an object of same or related type. The latter is when 
some dimensions get collapsed. E.g. a vector taken from a matrix, it is 
another type.

In the referential context it is even more complicated. A slice is 
always a type of different representation. As Randy has explained, Ada's 
built-in array types were designed with referential slices in mind.

It is a complex network of related types you cannot emulate with crude 
hacks like iterator interface.

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