From -3308542794059870134 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,edd477ec92e5348f X-Google-Attributes: gidf78e5,public X-Google-Thread: fc772,ef0c226459c03bdf X-Google-Attributes: gidfc772,public From: "Bill Wade" Subject: Re: Protected Inheritance Date: 1999/02/05 Message-ID: <79d2bd$fsf$1@uuneo.neosoft.com>#1/1 X-Deja-AN: 441110139 Approved: dom@devitto.demon.co.uk Sender: cppmods@netlab.cs.rpi.edu References: <79aesq$qlr$1@uuneo.neosoft.com> X-Submission-Address: c++-submit@netlab.cs.rpi.edu X-Approved-For-Group: Fergus Henderson comp.std.c++ X-Original-Date: 05 Feb 99 07:05:54 GMT Organization: NeoSoft, Inc. X-Auth: PGPMoose V1.1 PGP comp.lang.c++.moderated iQBVAwUANrtQb0HMCo9UcraBAQED0QH8DV3q8khF2M+Z6WB5+k7enoVi57nJxHXA wheD4eeUWuplges3QU2ep1aiP3jZPQ67Ll4Z4siLcOWnXgDLWNESAw== =SPbX Newsgroups: comp.lang.c++.moderated,comp.std.c++ Scott Meyers wrote in message ... > class Base { > public: > Base(); > }; > > class Derived: private virtual Base {}; > > class MoreDerived: public Derived {}; > > MoreDerived m; >The FDIS (and presumably the >standard -- I really should buy a copy, shouldn't I?) addresses the >matter >in 12.6.2. Paragraph 2 seems to back you up (I've omitted stuff that >doesn't seem germane here): Paragraph two talks about names, but not accessibility. Paragraph six (in the standard, I haven't checked FDIS) says for this case: "[Base is] initialized by the constructor of [MoreDerived.] ... If [Base] does not have an accessible default constructor, the initialization is ill formed." So I think this means that virtual base classes should never be private in a class intended for derivation. Note that MoreDerived could be changed to be legal: class MoreDerived: public Derived, private virtual Base {}; but the developer has to look at Derived's private stuff to figure this out. --- [ 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 ]