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From: Maciej Sobczak <see.my.homepage@gmail.com>
Newsgroups: comp.lang.ada
Subject: Discriminants of tagged types
Date: Wed, 27 Oct 2010 05:16:39 -0700 (PDT)
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Date: 2010-10-27T05:16:39-07:00
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Hi,

I'm not sure if I have already complatined about it, but as I have hit
that problem again, here it goes:

GNAT says that discriminants of tagged types cannot have default
values.
So this is OK:

   type T (A : Integer := 0) is null record;

but this is an error:

   type T (A : Integer := 0) is tagged null record;

I find it disturbing and artificial, but perhaps I don't see the big
picture. What is the rationale for this limitation?

--
Maciej Sobczak * http://www.inspirel.com