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From: dewar@gnat.com (Robert Dewar)
Newsgroups: comp.lang.ada
Subject: Re: Slices of 2d arrays?
Date: 24 Jul 2002 17:33:52 -0700
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Peter Hermann <ica2ph@iris16.csv.ica.uni-stuttgart.de> wrote in message news:<ahmb67$jjb$1@news.uni-stuttgart.de>...
>    g(1   ,4   ) is of type character
>    g(1..1,4..5) is of type grid
>    g(1   ,4..5) is of type grid slice?
>    g(1..1,4   ) is of type grid slice?
>    and the n-dimensional arrays?
> 
> No.   Language designers will certainly refusei, IMHO.

It is not hard to work out the semantics of this feature,
just see Algol-68 for inspiration.

However, as soon as you extend slices to >1D arrays, the
feature no longer obeys the "Bauer Principle" which says
that you should not pay overhead for a feature unless
you use it. That's because general slicing results in
non-standard strides, and you have to allow for this
whether or not such slicing is used.