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From: Niklas Holsti <nholsti@icon.fi>
Subject: Re: VIDEO MEMORY ACCESS WITH POINTERS
Date: 1999/11/29
Message-ID: <3842F727.48B74003@icon.fi>#1/1
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Date: 1999-11-29T00:00:00+00:00
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Nick Roberts wrote:
  [ snip ]

> Strictly, this solution needs two extra declarations:
> 
>    for video_cell'Size use 16;
> 
>    for video_memory_type'Component_Size use 16;
> 
> ... It may be more convenient to
> declare the array as a two-dimensional array, but (interestingly) the
> Ada standard provides no way to specify or interrogate whether an array
> is stored in row-major or column-major order, so you can't do this if
> you need portability.

Well, it is perhaps perverse in this context, but you
could ensure column-major order by

   pragma Convention (Fortran, TheArray);

but even I wouldn't use the above for video memory access :-)

Regards,
Niklas

Working at but not speaking for Space Systems Finland Ltd.