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Date: Mon, 18 Jan 2010 18:17:20 +0100
From: Georg Bauhaus <rm.dash-bauhaus@futureapps.de>
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Subject: Re: Writing an Operating System in Ada
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Date: 2010-01-18T18:17:21+01:00
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Dmitry A. Kazakov schrieb:

> There is a common ancestor for both types. What you probably had in mind
> was a conversion is between types from independent hierarchies rooted on
> different hosts. That normally should not be needed.

Well, I learned from the discussion that independent roots of
blobs' types it is a quite common case.
In fact, it is the very cases on which the objections were based.

> To me the problem rather is in passing the concrete type of Y, which the
> program will never have to learn, but the run-time must. It will modify the
> dispatching tables, take the implementations of overridden operations in
> the form of some byte code (?) etc.

Right.  The modifiable dispatching tables are the
interesting part or an O-O file system. I guess that CORBA and
Microsoft CORBA (.NET) may offer some hints.