Re: Base - derived problem. - Article 114 - go-pugleaf

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Re: Base - derived problem.

#114

From: Chris Newton
Date: Mon, 26 Jul 1999 00:00

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Tony Colston wrote...
> I think that your problem has something to do with when
> an object get constructed.

Or even how it gets constructed :-).  You are quite right, though, the
explanation is that when the base class's constructor is called, the object
is still only an instance of the base class, it is not yet an instance of
the derived class.  Hence, the base class's version of the virtual function
is called.  The C++ FAQ, at
  http://www.cs.bham.ac.uk/~jdm/CPP/index.html
has a little more explanation.

As for how to get around the problem, don't quote me, but I believe Meyers
discusses this issue in either Effective C++ or More Effective C++.  I don't
have my copies to hand, but I'll try to look them up later.

Regards,
Chris

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From: "Chris Newton" <can21@spamfree.cam.ac.uk>
Subject: Re: Base - derived problem.
Date: 1999/07/26
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