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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: How to test object hierarchy
Date: 19 Dec 2003 18:26:25 -0500
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Hyman Rosen <hyrosen@mail.com> writes:

> Dmitry A. Kazakov wrote:
> > You have to override Test_Hierarchy for each new type
> 
> Which brings a question to my non Ada-knowing mind.
> I know that for a subprogram to be dispatching, it
> must be defined in the same package (or immediately
> after?) as the tagged type upon which it dispatches.

It must defined in the same package *spec* (visible part or private
part).

One obscure point is that if you override an inherited subprogram, it is
dispatching.  It has to be declared in the same declarative region in
that case.

> Can an instantiation of a generic be dispatching in
> this way?

Yes, it can be instance.  It can also be a renaming.

>... Could I do (pardon the syntax errors)
>      procedure Test_Hierarchy is new
> 	Generic_Test_Hierarchy(Type1=>Derived_Object);
> rather than copy the code each time?

I didn't follow the entire discussion, but yes, I think that could work.

- Bob