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Date: Mon, 05 Jan 2004 10:35:47 -0500
From: Hyman Rosen <hyrosen@mail.com>
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Subject: Re: SIGada Conference
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Date: 2004-01-05T10:35:47-05:00
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Jean-Pierre Rosen wrote:
 > presumably because I never met a need for it!

I think it has its place in some low-level framework
code, as a means of querying whether an object supports
a particular interface. In any case, it's an ability
that exists with MI or interfaces, and you need to know
about it when thinking about ways to emulate those
features without fully supporting them. Typically, this
kind of interface querying involves a runtime search in
the type information structure or virtual table of the
object being examined, and that's not available in the
homebrew version.