From -9108278199480602321 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,23a9d1bd670d3257 X-Google-Attributes: gidf78e5,public From: JHB NIJHOF Subject: Re: Multiple inheritance and base class access with repeated bases Date: 1998/05/20 Message-ID: <6jt7ub$71u$1@whatsit.aston.ac.uk>#1/1 X-Deja-AN: 354870531 Approved: Fergus Henderson References: <01bd8309$63568200$3aace5cf@dave> Delivered-To: comp-std-c++@news.pipex.net X-Original-Date: 20 May 1998 00:25:47 GMT Organization: Aston University X-Auth: PGPMoose V1.1 PGP comp.std.c++ iQBEAgUANWJ83eEDnX0m9pzZAQFhAwF3YDVgVvqdB7WlnjKp3zq1sOITH8he9voO qZ8gH3ZQ152MAcIsCtvOBcVtVNtg/Dc= =GiuP User-Agent: tin/pre-1.4-980226 (UNIX) (Linux/2.0.33 (i686)) Newsgroups: comp.std.c++ Dave J.G. wrote: : While testing an object streaming class I've been working on, I came up with this : monster: : Class A { public: int i ; } ; : Class B : public A { public: int i ; } ; : Class C : public A, public B { public: int i ; } ; : Class D : public A, public B, public C { public: int i ; } ; : This compiles okay ( with a 'repeated base' warning and a couple of derogatory : comments from the compiler ) but when I try to access D::A::i in a method ( not : shown ) of Class D, I get an ambiguous base error. No wonder. Class has 8 members i, four of which which are from class A: A = (Ai) B = ((Ai) Bi) C = ((Ai) ((Ai) Bi) Ci) D = ((Ai) ((Ai) Bi) ((Ai) ((Ai) Bi) Ci)) So the compiler cannot figure out which of the i-s from class A you want. Try virtual base clases. -- Jeroen Nijhof J.H.B.Nijhof@aston.ac.uk Accordion Links http://www-th.phys.rug.nl/~nijhojhb/accordions.html --- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@ncar.ucar.edu ] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://reality.sgi.com/austern_mti/std-c++/faq.html ]