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Date: Sun, 15 Jul 2012 23:33:30 +0200
From: Georg Bauhaus <rm.dash-bauhaus@futureapps.de>
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Subject: Re: Efficient Sequential Access to Arrays
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Date: 2012-07-15T23:33:30+02:00
List-Id: <comp.lang.ada>

On 15.07.12 22:16, Keean Schupke wrote:

> I am not sure such a rigorous analysis is necessary though, consider the following: the language semantics could be changed to allow this by for example having a primitive iterator type on arrays that supported operations like:
>
> declare
>      J : Array_Iterator := Array(5);
> begin
>      J := J + 1;
>      J.Property = Value;
> end
>
> This would not expose the underlying machine architecture and would allow the kind of optimisations needed. J could have a range derived from the array bounds to bounds check the access.
>
> It seems obvious enough that I am wondering if there is a way to do this that I missed?

IIUC, this would be along the lines of Ada 2012 iteration
syntax (the "of" loop)?

   for J of Some_array_5 loop
      J.Property := Value;
   end loop;

It is possible to define types that allow the above for containers,
not sure whether this extends to arrays.