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From: Richard Riehle <richard@adaworks.com>
Newsgroups: comp.lang.ada
Subject: Re: Assigning the value of a deferred constant?
Date: Tue, 18 Sep 2001 11:40:57 -0700
Organization: AdaWorks Software Engineering
Message-ID: <3BA79539.D7FEA4A9@adaworks.com>
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Date: 2001-09-18T18:38:34+00:00
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Ted Dennison wrote:

> In article <d7abqt09p6i75u5nf014dbge4o11a0534r@4ax.com>, Juanma Barranquero
> says...
>
> >And vaguely related: Is there any way to declare a deferred constant
> >and assign its value in the body of the declaring package, during
> >elaboration? Something like:
>
> Sure. Declare it as a function instead of a constant.

Ted makes an important point.   Except for limited types, deferred constants
should be promoted to functions.   In fact, it seems this is now a good policy
for most named numbers and declared values.   This leverages one of the
more powerful aspects of Ada:  the ability to defer the implementation of
a value to the body of a package.   It also goes a long way towared satisfying
the principle of referential transparency.

Richard Riehle
richard@adaworks.com