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From: Markus Schoepflin <nospam@no.spam>
Newsgroups: comp.lang.ada
Subject: Re: Enumeration representation clause surprise.
Date: Fri, 13 Jun 2008 16:45:09 +0200
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Xref: g2news1.google.com comp.lang.ada:694
Date: 2008-06-13T16:45:09+02:00
List-Id: <comp.lang.ada>

Mike Silva wrote:

> So that's why I'm wondering why compiler writers ever introduced biased
> representations in the first place.  I can't believe that the problem
> with this approach has only been noticed in 2008.

In the project where I was bitten by this, it is clearly not the first time
that this problem has occurred.

In my search for other occurrences of the problem in the full source code
(a few million SLOC) of the system, I discovered an old comment dating back
from 1996, indicating that they had the same issue back then.

> Aren't biased representations fundamentally incompatible with "the 
> representation clearly *does* matter"?

 From my point of view, biased representations and representation clauses
should be mutually exclusive. Whenever I care enough about the 
representation that I think it necessary to write a representation clause, 
the compiler shouldn't fiddle with that representation behind my back.

Markus