Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!newsfeed.xs4all.nl!newsfeed3.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; 'argument': 0.05; 'assign': 0.07; 'subject:instance': 0.09; 'variable,': 0.09; 'cc:addr :python-list': 0.11; '__lt__': 0.16; 'argument.': 0.16; 'from:addr:rosuav': 0.16; 'from:name:chris angelico': 0.16; 'ought': 0.16; 'set,': 0.16; 'subject: \n ': 0.16; 'subject:class': 0.16; 'subject:variable': 0.16; 'wrote:': 0.18; 'wed,': 0.18; '(the': 0.22; 'aug': 0.22; 'cc:addr:python.org': 0.22; 'cc:2**0': 0.24; 'function': 0.29; 'message- id:@mail.gmail.com': 0.30; '13,': 0.31; 'class': 0.32; 'becomes': 0.33; 'subject:from': 0.34; 'subject: (': 0.35; 'something': 0.35; 'received:google.com': 0.35; 'really': 0.36; 'method': 0.36; 'pm,': 0.38; 'first': 0.61; 'significance': 0.84; 'on?': 0.91; 'to:none': 0.92 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:cc:content-type; bh=OYBfUF2Na5Du4pznLbcULxiBjk7IRIZa6G2OnYqmWNk=; b=nq/PiFzgpapAEV68aVIzkHW8bYET1vxX1k6STSMCNjPo3GfFEGDVS9Jbyuv/xRhK0F Z0KVrqGquSegzF6d6sbVnXh/C8Nny7GcPAWC40C7JYTU3qfsAeY0Ah2yVeEOD60DcMqR f6E4wJd6q9GYxBZ6t84aA8RyWQ3xGvdwF5cg4L3FWfd6pdNmJwMLBkWiP5XcT1Rzc/EF KAO4SSjRdJqgDf2+O/GfIILHzXhBe6OyWYBWWRIN6fpJlSCZe/c4QhoyEWtM4EDOcUJT eJOwnWlqTYwpar9DeRjPKKgyIjK8tKpj7V8ZTsgCasxf/pv1R6G1Xpi7a8EvyMPO/SFg vf9Q== MIME-Version: 1.0 X-Received: by 10.42.216.148 with SMTP id hi20mr4782051icb.12.1407923498116; Wed, 13 Aug 2014 02:51:38 -0700 (PDT) Date: Wed, 13 Aug 2014 19:51:38 +1000 Subject: Arbitrary dunder attributes (was Re: odd difference calling function from class or instance variable) From: Chris Angelico Cc: "python-list@python.org" Content-Type: text/plain; charset=UTF-8 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: 15 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1407923500 news.xs4all.nl 2977 [2001:888:2000:d::a6]:59131 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:76181 On Wed, Aug 13, 2014 at 7:06 PM, GregS wrote: > When I assign the reference as a class variable, the reference has __self__ > set, too, so I get an extra argument passed to the function. If I assign > the reference as an instance variable, then __self__ is unset so no extra > argument. Spin-off from Greg's thread. The bound method object stores a reference to the original object (the thing that becomes the first argument to the target function) in __self__ (and the function in __func__). ISTM this ought to be _self (and _func), as it's intended to be private; is it really something that has language-level significance on par with __lt__ and so on? ChrisA