Re: private inheritance vs containment

From:
"Daniel T." <daniel_t@earthlink.net>
Newsgroups:
comp.lang.c++.moderated
Date:
Tue, 29 May 2007 01:40:37 CST
Message-ID:
<daniel_t-172375.23043028052007@news.west.earthlink.net>
Sam <sakarab@yahoo.com> wrote:

Daniel T. wrote:

Sam <sakarab@yahoo.com> wrote:

I know that this one has been discused many times and every
single book about C++ advices to first consider containment.

But I feel that there is a legitimate use of private inheritance
when a single condition is met (the base class has no virtual
functions, so inheriting from your class will not have a
customization point you don't intent to give) and the (small)
extra performance private inheritance gives is needed.

Any comments on my thinking.


Just the opposite is true.


I don't really understand what your point is. Can you elaborate
please?


Maybe the FAQ will help:
http://www.parashift.com/c++-faq-lite/private-inheritance.html#faq-24.3

My point is that a legitimate use of private inheritance is when the
base class *does* have at least one virtual function, and you want to
override that function, but don't want the child class to be convertible
into the parent class.

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