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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: How to access Vector.Index_Type?
Date: Mon, 18 Mar 2019 08:21:21 +0000
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Date: 2019-03-18T08:21:21+00:00
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jakub.dabek@gmail.com writes:

> Simon Wright writes:
>> You could use
>> 
>>    subtype My_Index_Type is MyVec.Extended_Index
>>      range MyVec.Extended_Index'First + 1 .. MyVec.Extended_Index'Last;
>
>
> This feels more like a "life-hack", requiring the knowledge of
> internal representation of `Extended_Index`. Is there really no better
> way to do that?

Well, as J-P Rosen has said, why would you ever need to do this in the
first place?

But, anyway, it's not an internal repreentation, it's public in ARM
A.18.2(7):
http://www.ada-auth.org/standards/rm12_w_tc1/html/RM-A-18-2.html#p7