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From: schmidt@siam.ics.uci.edu (Doug Schmidt)
Newsgroups: comp.lang.c++
Subject: Re: nit-picking - Edition #3 (multiple inheritance)
Keywords: nits
Message-ID: <14133@paris.ics.uci.edu>
Date: 12 May 89 06:12:38 GMT
References: <203@riunite.ACA.MCC.COM> <1527@cod.NOSC.MIL>
Sender: news@paris.ics.uci.edu
Reply-To: Doug Schmidt <schmidt@siam.ics.uci.edu>
Organization: University of California at Irvine: ICS Dept.
Lines: 65

Here's a quick nit.  Is the following a legal use of multiple
inheritance?  As you can see, from one direction class a's member
function `int foo ()' is private for all classes derived from class b.
However, on another path it is public.  In class d's constructor,
where `foo ()' is called, foo appears to be derived from classes where
it is both private and public.

Which visibility status prevails?  Is this ambiguous, legal, or illegal?

thanks,

        Doug

----------------------------------------
class a
{
public:
  int foo () { printf ("foo\n"); }
  a () {printf ("a\n");}
};

class b : public a
{
private:
  a::foo; // made private for all classes derived from class b.
public:
  b () {printf ("b\n");}
};

class c : public a
{
public:
  c () {printf ("c\n");}
};

class d : public c, public b
{
public:
  d () 
    {
      printf ("d\n"); 
      foo (); // both public *and* private!! which prevails?
    }
 };

class e : public d
{
public:
  e () 
    {
      printf ("e\n"); 
    } 
}

main ()
{
  e eek;
  b *beek = &eek;
}

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