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From: hyrosen@mail.com (Hyman Rosen)
Newsgroups: comp.std.c++
Subject: Re: Virtual Base Constructors
Date: Fri, 21 Feb 2003 16:44:14 +0000 (UTC)
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Hickman, Greg wrote:
> Do we really have to require that Base call the Io_object constructor even
> though it ultimately *has* to be handled by the Concrete type anyway?

No, quite the opposite. Base is required *not* to call the
Io_object constructor when Concrete is being constructed.
Despite appearances, a virtual base class is constructed
only once, from the most derived class.

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