From -7185613519043163549 X-Google-Thread: 7894ca11fe,ca1d48828e7eb066 X-Google-Attributes: gid7894ca11fe,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!news1.google.com!Xl.tags.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local2.nntp.dca.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Tue, 13 Oct 2009 12:00:05 -0500 Return-Path: To: (Usenet) From: Sean Hunt Newsgroups: comp.std.c++ Subject: Re: Keyword abstract for pure virtual functions in c++0x Organization: http://groups.google.com Sender: cppmods@cs.rpi.edu Approved: austern@google.com Message-ID: References: <64708d1f-cb87-4e3b-a1c8-845c98490c25@o41g2000yqb.googlegroups.com> <06f78e41-2741-4217-9d79-94bd729418d7@f20g2000prn.googlegroups.com> Content-Type: text/plain; charset=ISO-8859-1 X-Original-Date: Mon, 12 Oct 2009 17:06:02 -0700 (PDT) X-Submission-Address: std-c++@netlab.cs.rpi.edu Date: Tue, 13 Oct 2009 11:54:48 CST Lines: 27 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-pNMIhDNJAyTch7n0lYwFMS/YjsSWmrBLsxqqeSeIbu0y6pk6yEJnv+jPiRpiVBaxy+edkCTOUmxLnBc!PcmxE3wuJu+M41DRcgmo1YDlW3GwfbaL2ctOapR+HwY9zddgSeMWVTGS+TBI29FHkL1UqGl48bMh!WfzW1l8a92Bz9ycYpz4gyjKCjPE= X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Xref: g2news2.google.com comp.std.c++:1480 On Oct 11, 5:04 pm, PsiX wrote: > Thanks for the info! > > As for the why... why "x->" if there is "(*x)." why "!=" if there is ! > ( == )... why abstract if there is =0? > (being the difference in the meaning that the compiler does not create > a function body vs. the intention of what the programmer wants to say) > because it helps the reading and understanding of code. And you could > later say > abstract class X{}; [[abstract]] and [[concrete]] might be useful attributes for checking, but they wouldn't have any other use, as the abstractness of a class can be determined from its contents (note that an abstract class with no pure virtual members can very easily be done by making the destructor pure virtual; the destructor must be defined in derived classes so they don't notice that the parent is abstract). Sean Hunt -- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@netlab.cs.rpi.edu] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://www.comeaucomputing.com/csc/faq.html ]