Re: Friend functions not inherited

From:
Pete Becker <pete@versatilecoding.com>
Newsgroups:
comp.lang.c++
Date:
Thu, 4 Nov 2010 08:37:26 -0400
Message-ID:
<2010110408372613001-pete@versatilecodingcom>
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On 2010-11-04 06:37:47 -0400, Andrea Crotti said:

To my surprise I read that some time ago, so what I thought it could
work in fact it could not work.


If the title is an exact quote, you were misinformed. The actual rule
is that *friendship* is not inherited.

class Extended : Base


Now Extended has a *private* base named Base. Change it to

class Extended : public Base

and everything should work just fine. There's no problem calling
operator<<(ostream&, const Base&) with an object of type Extended.

--
  Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)
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<p class="p1">On 2010-11-04 06:37:47 -0400, Andrea Crotti said:</p>
<p class="p2"><br></p>
<p class="p3">To my surprise I read that some time ago, so what I thought it could</p>
<p class="p3">work in fact it could not work.</p>
<p class="p4"><br></p>
<p class="p5"><br></p>
<p class="p6">If the title is an exact quote, you were misinformed. The actual rule is that *friendship* is not inherited.</p>
<p class="p5"><br></p>
<p class="p3">class Extended : Base</p>
<p class="p7"><br></p>
<p class="p8">Now Extended has a *private* base named Base. Change it to</p>
<p class="p7"><br></p>
<p class="p8">class Extended : public Base</p>
<p class="p7"><br></p>
<p class="p8">and everything should work just fine. There's no problem calling operator&lt;&lt;(ostream&amp;, const Base&amp;) with an object of type Extended.</p>
<p class="p9"><br></p>
<p class="p10">--<span class="Apple-converted-space">?</span></p>
<p class="p10"><span class="Apple-converted-space">? </span>Pete</p>
<p class="p10">Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The Standard C++ Library Extensions: a Tutorial and Reference (www.petebecker.com/tr1book)</p>
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