Path: csiph.com!optima2.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!1.eu.feeder.erje.net!weretis.net!feeder4.news.weretis.net!feeds.phibee-telecom.net!newsfeed.xs4all.nl!newsfeed8.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 0.048 X-Spam-Evidence: '*H*': 0.90; '*S*': 0.00; 'modify': 0.04; '-tkc': 0.16; 'from:addr:python.list': 0.16; 'from:addr:tim.thechases.com': 0.16; 'from:name:tim chase': 0.16; 'function"': 0.16; 'well-known': 0.16; 'wrote:': 0.16; 'stefan': 0.18; "i've": 0.24; 'header:In-Reply-To:1': 0.24; 'tim': 0.24; 'chase': 0.29; 'url:wikipedia': 0.29; 'url:wiki': 0.30; 'similar': 0.32; 'common': 0.33; 'ram': 0.33; 'to:addr:python-list': 0.35; 'something': 0.35; 'but': 0.36; 'url:org': 0.36; 'heard': 0.36; 'received:10': 0.37; 'world,': 0.38; 'url:en': 0.39; 'does': 0.39; 'to:addr:python.org': 0.39; 'why': 0.40; 'term': 0.60; 'world': 0.64; 'believe': 0.67; 'received:23': 0.84; 'subject: ...': 0.84 X-Sender-Id: wwwh|x-authuser|tim@thechases.com X-Sender-Id: wwwh|x-authuser|tim@thechases.com X-MC-Relay: Neutral X-MailChannels-SenderId: wwwh|x-authuser|tim@thechases.com X-MailChannels-Auth-Id: wwwh X-MC-Loop-Signature: 1436128677865:679132193 X-MC-Ingress-Time: 1436128677865 Date: Sun, 5 Jul 2015 15:37:56 -0500 From: Tim Chase To: python-list@python.org Subject: Re: (side-)effects and ... In-Reply-To: <20150705153625.263a3b21@bigbox.christie.dr> References: <20150705153625.263a3b21@bigbox.christie.dr> X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.25; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-AuthUser: tim@thechases.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: 17 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1436133359 news.xs4all.nl 2887 [2001:888:2000:d::a6]:51517 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:93510 On 2015-07-05 15:36, Tim Chase wrote: > On 2015-07-05 20:29, Stefan Ram wrote: > > But why do we not have a common and well-known term for > > the counterpart, that something does not modify the state > > of the world, but that the state of the world does=20 > > influence the value (behaviour) of a call such as > > =C2=BBdatetime.datetime.now().time()=C2=AB? >=20 > I believe the term is "idempotent" >=20 > https://en.wikipedia.org/wiki/Idempotent_function#Computer_science_meaning Though I've also heard the term "pure function" for a similar meaning. https://en.wikipedia.org/wiki/Pure_function -tkc