Re: virtual operator+

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#83

From: Victor Bazarov
Date: Thu, 16 May 2002 23:30

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"Robert W Hand" <rwhand@NOSPAMoperamail.com> wrote...
> On Thu, 16 May 2002 21:31:31 GMT, "Daniel T." <notdanielt3@gte.net>
> wrote:
>
> >"Christopher Deli" <christopher@delinfo.com> wrote:
> >
> >>Hello!
> >>
> >>I have a problem which I'd need some help with, please.
> >>If I have one class A which is inherited by another class B i.e. class B
:
> >>public class A and I would like to make a virtual operator+ in both
class A
>
> >What is op+ supposed to return, an "A" object or a "B" object?
>
> Aren't the two return types A and B covariant?  The one in the A class
> would return an A object, and the one in the B class would return a B
> object.


No.  Covariance requires a pointer or a reference.  Operator +
returns an object, not a pointer and not a reference.

Victor
--
Please remove capital A's from my address when replying by mail

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From: "Victor Bazarov" <vAbazarov@dAnai.com>
Newsgroups: alt.comp.lang.learn.c-c++,att.lang.c++,comp.lang.c++
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Subject: Re: virtual operator+
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