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From: davidk@os1.ese.lmsc.lockheed.com (David Kristola)
Subject: Re: To Initialise or not
Date: 1996/05/11
Message-ID: <4n0lqa$9dt@butch.lmsc.lockheed.com>#1/1
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distribution: world
references: <31937B57.5B0@lmtas.lmco.com>
organization: SAMCO
reply-to: davidk@os1.ese.lmsc.lockheed.com
newsgroups: comp.lang.ada
Date: 1996-05-11T00:00:00+00:00
List-Id: <comp.lang.ada>



I apologize if this has already been brought up.  I missed it if it was.

You could always create a "bad" value to initialize pointers to, if null
is an acceptable alternative.  By this i mean something like:

   type Object is...
   type Reference is access Object;

   Bad_Reference : constant Reference := new Object; -- possibly with a "bad" bit set.

   ...

   procedure Do_Something is

      Pointer : Reference := Bad_Reference;

   begin
      ...
      if Pointer = Bad_Reference then
         ...
      elsif Pointer = null then

In Ada95, you can even have Bad_Reference pointing to a static object.

---

david kristola
Work: davidk@os1.ese.lmsc.lockheed.com
Play: DJKristola@aol.com