From 8970217941625648851 X-Google-Thread: f78e5,51456c3eb8f9490e X-Google-Attributes: gidf78e5,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!news1.google.com!news4.google.com!news.glorb.com!news.alt.net!comp-std-cpp-robomod!not-for-mail From: "mark" Newsgroups: comp.std.c++ Subject: Re: Copy Constructor Confusion! Date: Wed, 16 Aug 2006 11:22:36 CST Organization: http://groups.google.com Lines: 40 Approved: Fergus Henderson , moderator of comp.std.c++ Message-ID: <1155663179.843769.44420@b28g2000cwb.googlegroups.com> References: <1155645873.296811.3890@74g2000cwt.googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" X-Trace: posting.google.com 1155663184 21949 127.0.0.1 (15 Aug 2006 17:33:04 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Tue, 15 Aug 2006 17:33:04 +0000 (UTC) Return-Path: X-Authentication-Warning: mulga.csse.unimelb.edu.au: fjh set sender to devnull@stump.algebra.com using -f X-Robomod: STUMP, ichudov@algebra.com (Igor Chudov) X-Original-To: std-c++@mailman.ucar.edu Delivered-To: std-c++@mailman.ucar.edu User-Agent: G2/0.2 X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.6) Gecko/20060728 Firefox/1.5.0.6,gzip(gfe),gzip(gfe) Complaints-To: groups-abuse@google.com Injection-Info: b28g2000cwb.googlegroups.com; posting-host=207.135.74.34; posting-account=kmJZpwwAAADTaEqNJ8z_rfhCwbaAxYpY X-Virus-Scanned: amavisd-new at ucar.edu X-Virus-Scanned: amavisd-new at csse.unimelb.edu.au X-Virus-Scanned: amavisd-new at csse.unimelb.edu.au Xref: g2news2.google.com comp.std.c++:3303 "Victor Bazarov" wrote: > Shouldn't this be moved to a .lang. newsgroup? Just checking... > > Frederick Gotham wrote: > > Thomas posted: > > > >> Hello fellow programmers! > >> > >> I have a c++ line: > >> > >> X x = X(); > >> > >> Does the standard say that the class X must have a public copy > >> constructor for this to be legal, even if the copy constructor never > >> gets called? > > > > > > Yes, although it gives explicit permission to the compiler to elide > > the creation of the redudant temporary object. Even if the temporary > > is elided, the copy-constructor must still be public. > > Not "public", *accessible*. If the "c++ line" above appears inside > a friend function, it would work just fine with a private copy c-tor. Yes. > If it appears inside a member of a derived class, "protected" should > suffice. Really? Mark Williams --- [ 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://www.comeaucomputing.com/csc/faq.html ]