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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: What is X'Address of an empty array?
Date: Tue, 31 May 2022 14:19:24 +0200
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I have a language lawyering question. According to ARM X'Address is the 
address of the first array element. What is the address of empty array?

In the case of an array with bounds it could be the address following 
the bounds.

But what about a definite empty array? Of zero length (and presumably 
zero size). Would the compiler have to invent some address?

P.S. With GNAT:

    type NUL is array (1..0) of Integer;
    S : NUL;

S'Size is 8 and it has some address that holds the byte.

Talking about the dark matter in our Universe. This is what empty arrays 
are constructed of! (:-))

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de