From -5378702873496223566 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,16c102c32134aea8,start X-Google-Attributes: gidf78e5,public From: scleary@jerviswebb.com Subject: Defect Report: Unnecessary restriction on past-the-end iterators Date: 2000/02/03 Message-ID: <538B4E4235ECD211B35B0090273CC28B012E28@CECEXCHANGE>#1/1 X-Deja-AN: 581159539 Content-Transfer-Encoding: 7bit Approved: stephen.clamage@sun.com (comp.std.c++) X-UID: 0000000001 X-Priority: 3 (Normal) X-Status: $$$T Content-Type: text/plain; charset="iso-8859-1" X-MimeOLE: Produced By Microsoft MimeOLE V4.72.3110.3 Importance: Normal Organization: - X-MSMail-Priority: Normal Mime-Version: 1.0 Reply-To: Newsgroups: comp.std.c++ Originator: clamage@taumet [Moderator's note: forwarded to C++ Committee. -sdc ] Unnecessary restriction on past-the-end iterators Section: 24.1 [Iterator requirements] Submitter: Stephen Cleary Date: 02 February 2000 In 24.1 [Iterator requirements] paragraph 5, it is stated ". . . Dereferenceable and past-the-end values are always non-singular." This places an unnecessary restriction on past-the-end iterators for containers with forward iterators (for example, a singly-linked list). If the past-the-end value on such a container was a well-known singular value, it would still satisfy all forward iterator requirements. Removing this restriction would allow, for example, a singly-linked list without a "footer" node. This would have an impact on existing code that expects past-the-end iterators obtained from different (generic) containers being not equal. Proposed Resolution: Change the wording of 24.1 [Iterator requirements] paragraph 5 to ". . . Dereferenceable values are always non-singular. If the iterator category is bidirectional or random access, a past-the-end value of that iterator is always non-singular." -Steve [ 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 ]