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From: "Alejandro R. Mosteo" <alejandro@mosteo.com>
Newsgroups: comp.lang.ada
Subject: 'Class'Class'Class'Class ad libitum
Date: Tue, 13 Sep 2016 12:43:36 +0200
Organization: A noiseless patient Spider
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Date: 2016-09-13T12:43:36+02:00
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I get why this is legal:

    type X is tagged null record;

    subtype Y is X'Class;

    subtype Z is X'Class'Class'Class'Class;

But can you think of any legitimate reason to use it besides obfuscation?

Álex