Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder4.news.weretis.net!feeds.phibee-telecom.net!newsfeed.xs4all.nl!newsfeed4a.news.xs4all.nl!xs4all!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 0.001 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'subject:Python': 0.06; '*not*': 0.07; 'assignment': 0.07; 'users,': 0.07; 'string': 0.09; 'latter': 0.09; 'parameter': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'subject:into': 0.09; 'python': 0.11; 'finney': 0.16; 'ignoring': 0.16; 'preserve': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'reliably': 0.16; 'subject:variable': 0.16; 'value.': 0.19; 'header:User-Agent:1': 0.23; 'comparing': 0.24; 'question': 0.24; 'references': 0.26; 'defined': 0.27; 'header:X-Complaints-To:1': 0.27; 'point': 0.28; "i'm": 0.30; 'adams': 0.31; 'object.': 0.31; 'writes:': 0.31; 'run': 0.32; '(including': 0.33; 'common': 0.35; 'no,': 0.35; 'objects': 0.35; 'really': 0.36; 'received:com.au': 0.36; 'subject:?': 0.36; 'being': 0.38; 'ben': 0.38; 'to:addr :python-list': 0.38; 'to:addr:python.org': 0.39; 'received:org': 0.40; 'skip:u 10': 0.60; 'subject:Can': 0.60; 'no.': 0.61; "you're": 0.61; 'first': 0.61; 'telling': 0.64; 'different': 0.65; 'guaranteed': 0.75; 'perspective.': 0.84; 'received:125': 0.84 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Ben Finney Subject: Re: Can global variable be passed into Python function? Date: Sun, 02 Mar 2014 09:34:15 +1100 References: <27ac2248-0ca3-4ba6-9d25-eaad324bc5e9@googlegroups.com> <5f4f5a5f-327a-4616-8235-17ee9e74c488@googlegroups.com> <530fef58$0$11113$c3e8da3@news.astraweb.com> <871tynznpd.fsf@elektro.pacujo.net> <53104798$0$11113$c3e8da3@news.astraweb.com> <87ha7jy2qs.fsf@elektro.pacujo.net> <87k3ceeq0m.fsf@elektro.pacujo.net> <87zjlad8q4.fsf@elektro.pacujo.net> <874n3irz04.fsf@elektro.pacujo.net> <87k3ceqhti.fsf@elektro.pacujo.net> <87r46l96j6.fsf@elektro.pacujo.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Gmane-NNTP-Posting-Host: vmx15867.hosting24.com.au X-Public-Key-ID: 0xBD41714B X-Public-Key-Fingerprint: 9CFE 12B0 791A 4267 887F 520C B7AC 2E51 BD41 714B X-Public-Key-URL: http://www.benfinney.id.au/contact/bfinney-gpg.asc X-Post-From: Ben Finney User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.4 (gnu/linux) Cancel-Lock: sha1:ogrUYhEqEHUaobUQHmxVZgqT8IE= X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 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: 28 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1393713311 news.xs4all.nl 2911 [2001:888:2000:d::a6]:52785 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:67385 Marko Rauhamaa writes: > Ben Finney : > > > No. I'm telling you that ‘is’ is *wrong* for comparing strings, > > because it is unreliable. > > No, it isn't as long as the string object references have a common > assignment "pedigree." Assignment (including parameter passing) is > guaranteed to preserve identity of any object. The unreliability isn't “will the same object have the same identity?”. The unreliability is “will objects defined elsewhere have a different identity?” In the case of Python strings, the latter question is not reliably answerable from the programmer's perspective. You are obstinately ignoring the point that the identity of a string is *not* guaranteed to be different from a string with the same value. Since you're persistently misconstruing what is being said to you, I'm not going to run through it all again. -- \ “[W]e are still the first generation of users, and for all that | `\ we may have invented the net, we still don't really get it.” | _o__) —Douglas Adams | Ben Finney