Path: csiph.com!news.mixmin.net!newsreader4.netcologne.de!news.netcologne.de!bcyclone01.am1.xlned.com!bcyclone01.am1.xlned.com!newsfeed.xs4all.nl!newsfeed8.news.xs4all.nl!nzpost1.xs4all.net!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.018 X-Spam-Evidence: '*H*': 0.96; '*S*': 0.00; 'attributes': 0.07; 'url:pycon': 0.08; 'empty,': 0.09; 'it;': 0.09; 'objects)': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'python': 0.10; 'iterating': 0.16; 'objects).': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'subject:reference': 0.16; 'subject:versus': 0.16; 'url:display': 0.16; 'url:py': 0.16; "i've": 0.25; 'header:User-Agent:1': 0.26; 'header:X-Complaints- To:1': 0.26; '[2]': 0.27; 'object,': 0.27; 'start,': 0.27; 'objects': 0.29; 'another': 0.32; "can't": 0.32; '[1]': 0.32; 'point': 0.33; 'url:python': 0.33; 'url:%4': 0.33; 'message- id:@gmail.com': 0.34; 'structure': 0.34; 'exist': 0.35; 'step': 0.36; 'but': 0.36; 'subject:" ': 0.36; 'to:addr:python-list': 0.36; 'subject:: ': 0.37; 'received:org': 0.37; 'why': 0.39; 'to:addr:python.org': 0.40; 'url:3': 0.60; 'different': 0.63; 'url:6': 0.66; 'url:js': 0.66; 'talking': 0.67; 'physical': 0.72; 'received:89': 0.80; 'stop,': 0.84; 'url:2007': 0.84; 'url:a1': 0.84; 'url:false': 0.84; 'url:mode': 0.84; 'url:origin': 0.84; 'url:%0a': 0.91 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Akira Li <4kir4.1i@gmail.com> Subject: Re: Terminology: "reference" versus "pointer" Date: Mon, 14 Sep 2015 17:48:36 +0300 References: <85mvws6z45.fsf_-_@benfinney.id.au> <85io7g6xy4.fsf@benfinney.id.au> <85egi46wng.fsf@benfinney.id.au> <1a1a1f6a-27ce-4c1b-807a-43eabaa04abb@googlegroups.com> <04ca9d7c-d02b-4329-bd94-4d18d86b3edf@googlegroups.com> <87egi375wb.fsf@gmail.com> <87wpvu5h7f.fsf@gmail.com> <87pp1l6h9a.fsf@gmail.com> <1442187517.2372486.382584889.2ED1B071@webmail.messagingengine.com> Mime-Version: 1.0 Content-Type: text/plain X-Gmane-NNTP-Posting-Host: 89.169.229.68 User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (gnu/linux) Cancel-Lock: sha1:07z5rW3pHbTLlmIY64SspjsVYwE= 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: 23 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1442242210 news.xs4all.nl 23832 [2001:888:2000:d::a6]:43000 X-Complaints-To: abuse@xs4all.nl X-Received-Bytes: 4850 X-Received-Body-CRC: 3350168696 Xref: csiph.com comp.lang.python:96569 Random832 writes: ... > Why can't it describe range(1)? A range object in my model would include > the start, stop, and step; _not_ the contents of what you would get by > iterating over it; since that's not part of the physical structure of > the object, but the consequences of calling methods on it. start, stop, step attributes (corresponding Python ints) may not exist ("the objects we've talking about have never been created") until you request them explicitly. I've mentioned it in another message but to be clear, I consider "parcel tags" [1] and "box and arrows" [2] (boxes are always empty, they only point to objects) models to be the same and different from "labelled box" [3] model (boxes contain objects). [1] http://python.net/~goodger/projects/pycon/2007/idiomatic/handout.html#python-has-names [2] http://www.pythontutor.com/visualize.html#code=a0+%3D+a1+%3D+%5B1,+2%5D%0Ab0+%3D+%5B1,+2%5D%0Ab1+%3D+%5B1,+2%5D%0Aa+%3D+%5Ba0,+a1%5D%0Ab+%3D+%5Bb0,+b1%5D%0Adel+a0,+a1,+b0,+b1%0A&mode=display&origin=opt-frontend.js&cumulative=false&heapPrimitives=false&textReferences=false&py=3&rawInputLstJSON=%5B%5D&curInstr=6 [3] http://python.net/~goodger/projects/pycon/2007/idiomatic/handout.html#other-languages-have-variables