Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!aioe.org!feeder.news-service.com!xlned.com!feeder7.xlned.com!news2.euro.net!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 0.012 X-Spam-Evidence: '*H*': 0.98; '*S*': 0.00; 'wed,': 0.03; 'run-time': 0.05; 'subject:()': 0.09; 'subject:blog': 0.09; 'am,': 0.14; 'wrote:': 0.14; '(b,': 0.16; 'a()': 0.16; 'billy': 0.16; 'mro': 0.16; 'object).': 0.16; 'suggest': 0.19; 'object,': 0.19; 'header :In-Reply-To:1': 0.21; 'seems': 0.21; 'resolution': 0.21; 'name?': 0.23; 'received:209.85.161.46': 0.23; 'received:mail- fx0-f46.google.com': 0.23; "doesn't": 0.25; 'subject:use': 0.25; 'received:209.85.161': 0.26; 'object': 0.26; 'message- id:@mail.gmail.com': 0.28; 'subject:how': 0.29; 'class': 0.29; 'subject:post': 0.30; 'determined': 0.32; 'to:addr:python-list': 0.33; '...': 0.34; 'example,': 0.35; 'there': 0.35; 'instances': 0.35; 'sense,': 0.35; 'thus,': 0.35; 'actual': 0.36; 'received:google.com': 0.37; 'something': 0.37; 'received:209.85': 0.37; 'pretty': 0.37; 'but': 0.38; 'subject:: ': 0.38; 'received:209': 0.39; 'to:addr:python.org': 0.39; 'your': 0.60; 'order': 0.62; 'super': 0.63; 'day,': 0.64; 'vary': 0.65; 'special': 0.66; 'stand': 0.71; 'article': 0.76; 'post)': 0.84 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:from:date :message-id:subject:to:content-type:content-transfer-encoding; bh=ekQWvD7A+I92r//HTUkUJCTImPck1XfWJoJ+INO6bQU=; b=HvbHf9ZMVyoAEiXpM95xQD5b+eBhPMDLXqqGoCsLWHPp4/C5nrH+X7cXkhH8K1oY+K aCfW7Ytq8X+RdCxUN7Zg9DueC65+MZKSZVeckWXDVvpnSx7gfv4Xa8Zr2bg3JdNxL3HG 9746qO6YgsnhAftefgvtGnljWhqVwEHRCV9k8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type:content-transfer-encoding; b=IN7UNbZs2AeNTf86sWVtKO7rn7QcP6T+0RiZtAxJcPnKnZbhHwoQ/dMvCZeyy6jDpy 3Po/RYbHL1ABbFkC1BNK3RM3u5iMxhMnxFL4q05r5Kxje4fqRVqqY44eDoRTdPgsfBQR l26aerhz4R4KjqcD5Zl+JZ67fpIc+P7n5Khv4= MIME-Version: 1.0 In-Reply-To: References: <80476fba-1b57-4bb1-9d7d-391edaf3042d@22g2000prx.googlegroups.com> From: Ian Kelly Date: Wed, 1 Jun 2011 10:42:06 -0600 Subject: Re: Updated blog post on how to use super() To: python-list@python.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.12 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: 34 NNTP-Posting-Host: 82.94.164.166 X-Trace: 1306946563 news.xs4all.nl 49179 [::ffff:82.94.164.166]:54516 X-Complaints-To: abuse@xs4all.nl Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:6799 On Wed, Jun 1, 2011 at 7:03 AM, Billy Mays wrote: > I read this when it was on HN the other day, but I still don't see what i= s > special about super(). =A0It seems (from your post) to just be a stand in= for > the super class name? =A0Is there something special I missed? It's not a stand-in for the super-class name. It's a stand-in for whatever class is next in the Method Resolution Order (MRO), which is determined at run-time and can vary depending on what the actual class of the object is. For example, in this inheritance situation: class A(object): ... class B(object): ... class C(A, B): ... a =3D A() c =3D C() The MRO of A is (A, object). The MRO of B is (B, object). The MRO of C is (C, A, B, object). Thus, super(A, a) is going to resolve to object, as you might expect. But super(A, c) is going to resolve to B, because the next class after A in the MRO for C instances is B. That's a pretty quick and dirty explanation. If it doesn't make sense, I suggest reading the article again.