Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!news.mixmin.net!rt.uk.eu.org!newsfeed.xs4all.nl!newsfeed2.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 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'example:': 0.03; 'output': 0.05; 'represents': 0.05; 'level,': 0.07; 'nested': 0.07; 'logic': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'spaces': 0.09; 'def': 0.12; '*always*': 0.16; 'comma': 0.16; 'formatted': 0.16; 'indent': 0.16; 'item:': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'requested.': 0.16; 'stan': 0.16; 'elements': 0.16; 'wrote:': 0.18; 'trying': 0.19; 'seems': 0.21; '(the': 0.22; 'print': 0.22; 'header:User-Agent:1': 0.23; 'this:': 0.26; 'header:X-Complaints-To:1': 0.27; 'gives': 0.31; '-0700,': 0.31; "d'aprano": 0.31; 'grouping': 0.31; 'sep': 0.31; 'steven': 0.31; 'way?': 0.31; 'figure': 0.32; 'another': 0.32; 'problem': 0.35; 'subject:with': 0.35; 'but': 0.35; 'next': 0.36; 'charset:us-ascii': 0.36; 'so,': 0.37; 'list': 0.37; 'level': 0.37; 'follows:': 0.38; 'to:addr:python-list': 0.38; 'rather': 0.38; 'little': 0.38; 'to:addr:python.org': 0.39; 'skip:p 20': 0.39; 'received:org': 0.40; 'how': 0.40; 'first': 0.61; 'said:': 0.68; 'greetings': 0.72; 'all!': 0.84; 'legs': 0.84; 'subject:Lists': 0.91; '2013': 0.98 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Dave Angel Subject: Re: Dealing with Lists Date: Wed, 11 Sep 2013 02:24:44 +0000 (UTC) References: <33650fe9-802e-477d-a361-6d4bdeb28762@googlegroups.com> <522fd1ee$0$29988$c3e8da3$5496439d@news.astraweb.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: 174.32.174.36 User-Agent: XPN/1.2.6 (Street Spirit ; Linux) 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: 60 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1378866311 news.xs4all.nl 15923 [2001:888:2000:d::a6]:54130 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:53938 On 10/9/2013 22:14, Steven D'Aprano wrote: > On Tue, 10 Sep 2013 14:08:45 -0700, stas poritskiy wrote: > >> Greetings to all! >> >> i ran into a little logic problem and trying to figure it out. >> >> my case is as follows: >> >> i have a list of items each item represents a Group >> i need to create a set of nested groups, >> so, for example: >> >> myGroups = ["head", "neck", "arms", "legs"] > > > What is the rule for grouping these items? Below, you suggest: > > head encloses neck > neck encloses arms > arms encloses legs > > which seems rather strange. But if it is *always* the case that each item > encloses the next item: > > def print_nested_list(alist): > spaces = ' '*4 > for level, item in enumerate(alist): > if level != 0: > indent = spaces*(level-1) + ' ' > print (indent + '|_>'), # note comma > print item > > > which gives us this: > > py> print_nested_list(['head', 'neck', 'arms', 'legs']) > head > |_> neck > |_> arms > |_> legs > > > as requested. > > Very nice. But what I want to know is how did you know that Stan (the OP) wanted his printed output to be formatted that way? He said: >>>>> i need to create a set of nested groups, and >>>>> store each of the first elements of a par, so I can reference to them as to a parent of another group. -- DaveA