Path: csiph.com!usenet.pasdenom.info!news.redatomik.org!newsfeed.xs4all.nl!newsfeed2a.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.003 X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'operator': 0.03; 'from:addr:yahoo.co.uk': 0.05; 'interpreter.': 0.07; 'patch.': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'bug': 0.10; 'python': 0.11; 'convey': 0.16; 'helpers': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'wrote:': 0.16; 'documented': 0.18; 'language': 0.19; '>>>': 0.20; 'tracker': 0.20; 'lawrence': 0.22; 'pass': 0.22; '2015': 0.23; 'module': 0.23; 'header:In-Reply-To:1': 0.24; 'raise': 0.24; 'developers': 0.24; 'header:User-Agent:1': 0.26; 'header:X -Complaints-To:1': 0.26; '(e.g.': 0.27; "doesn't": 0.28; 'methods.': 0.29; 'protocols': 0.29; 'guess': 0.29; 'that.': 0.30; 'core': 0.32; 'language.': 0.32; "d'aprano": 0.33; 'instead,': 0.33; 'steven': 0.33; 'to:addr:python-list': 0.35; 'acceptable': 0.35; 'possible,': 0.35; 'protocol': 0.35; 'but': 0.36; 'possible.': 0.36; 'should': 0.37; 'subject:: ': 0.37; 'tue,': 0.38; 'received:org': 0.38; 'pm,': 0.39; 'to:addr:python.org': 0.39; 'mark': 0.40; 'some': 0.40; 'easy': 0.60; 'course': 0.64; 'our': 0.64; 'charset:windows-1252': 0.65; '26,': 0.72; 'directly.': 0.76; 'lack': 0.76; 'received:89': 0.80; 'pythonistas,': 0.84; 'utc+5:30,': 0.84 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Mark Lawrence Subject: Re: Documentaion of dunder methods Date: Tue, 26 May 2015 08:24:38 +0100 References: <5563d7bb$0$12982$c3e8da3$5496439d@news.astraweb.com> <5563e5e8$0$12983$c3e8da3$5496439d@news.astraweb.com> <0c3aeb41-aaf9-4453-9ccc-b2c8891f1394@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: host-89-240-166-61.as13285.net User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 In-Reply-To: <0c3aeb41-aaf9-4453-9ccc-b2c8891f1394@googlegroups.com> X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.20+ Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 33 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1432625102 news.xs4all.nl 2958 [2001:888:2000:d::a6]:45113 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:91237 On 26/05/2015 04:30, Rustom Mody wrote: > On Tuesday, May 26, 2015 at 8:48:11 AM UTC+5:30, Steven D'Aprano wrote: >> On Tue, 26 May 2015 12:17 pm, Steven D'Aprano wrote: >> >>> In other words, dunder methods are reserved for use by the core developers >>> for the use of the Python interpreter. >> >> Er, that's easy to misinterpret. Let me try rewording: >> >> You should not invent new dunder methods. >> >> And if possible, you should not call such dunder methods directly. Instead, >> use the official protocol (e.g. next(x), not x.__next__()) whenever >> possible. The operator module contains many helpers for that. >> >> But of course you may *write* dunder methods. > > I guess you and I know what we want to convey and to proscribe. > However the above doesn't pass muster as documentation > The most glaring lack in the docs is some reification of the acceptable > 'protocols'. > Yeah people like to wax about duck-typing but that translates into semi-formal > protocols and they are just not documented > All you need do is raise an issue on the bug tracker with an attached patch. -- My fellow Pythonistas, ask not what our language can do for you, ask what you can do for our language. Mark Lawrence