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From: Dmitry A. Kazakov <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: How do I create an object instance from a tag?
Date: Wed, 19 Feb 2003 10:18:56 +0100
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On Wed, 19 Feb 2003 02:27:03 GMT, "Steve" <nospam_steved94@attbi.com>
wrote:

>What I "thought" was intuitive was something like:
>  myTag : Tags.Tag;
>  value : data_type'class;
>  for Value'Tag use myTag;
>
>Of course that doesn't work.

IMO, the following is more consistent:

   myTag : Tags.Tag := ...;
   value   : data_type'class (myTag);

and for dispatching:

   myTag : Tags.Tag := ...;
   value   : data_type'class (myTag) := Create_Value;

or fully dynamically (qualified expression):

   myTag : Tags.Tag := ...;
   value   : data_type'class :=
       data_type'class (myTag)'(Create_Value);

---
Regards,
Dmitry Kazakov
www.dmitry-kazakov.de