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From: "J-P. Rosen" <rosen@adalog.fr>
Newsgroups: comp.lang.ada
Subject: Re: Ensuring postconditions in the face of exceptions
Date: Mon, 15 Mar 2010 15:16:12 +0100
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Ludovic Brenta a �crit :

>> May be a (6) option is to create a tagged type ?
> 
> I see this as a variant of (2) and has the same drawbacks. In this
> case I would have to explain why I use a tagged type that has no
> primitive operations (the procedure Refresh does not have to be
> primitive for this type) and no type extensions .
> 
Proposal (7):

Make Dirty a (limited) private type -say Status- with functions Is_Dirty
and Is_Clean. You are then free to implement it as a by-reference type.

If it's a mess, hide it...

-- 
---------------------------------------------------------
           J-P. Rosen (rosen@adalog.fr)
Visit Adalog's web site at http://www.adalog.fr