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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Array Help?
Date: Thu, 01 Mar 2012 09:03:22 -0500
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Date: 2012-03-01T09:03:22-05:00
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Ludovic Brenta <ludovic@ludovic-brenta.org> writes:

> Robert A Duff writes on comp.lang.ada:
>>      Foo (Slide(A (3 .. 8)));
>
> Doesn't that involve copy-in and copy-out between the slice and a
> temporary object of type Slide?  Grossly inefficient, methinks.

No, I don't see any need for the compiler to make a copy here.
It just needs to pass the 1..6 bounds, plus a pointer to
the array elements.

I'm too lazy to check the machine code to see whether GNAT
makes a copy, but I don't see why it would.  Nor any other
Ada compiler.

- Bob