Path: csiph.com!usenet.pasdenom.info!news.albasani.net!newsfeed.freenet.ag!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 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'discard': 0.05; 'python': 0.09; 'bit...': 0.09; 'lst': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'consume': 0.16; 'from:addr:pobox.com': 0.16; 'from:addr:skip': 0.16; 'iterable': 0.16; 'iterator': 0.16; 'iterator,': 0.16; 'iterator.': 0.16; 'iterators': 0.16; 'itertools': 0.16; 'message-id:@post.gmane.org': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'subject:doc': 0.16; 'skip': 0.17; 'object.': 0.22; 'pass': 0.25; 'header:User-Agent:1': 0.26; 'header:X-Complaints-To:1': 0.28; 'implicitly': 0.29; 'writes:': 0.29; 'stuff': 0.30; 'to:addr :python-list': 0.33; 'version': 0.34; 'thanks': 0.34; 'received:org': 0.36; 'but': 0.36; 'charset:us-ascii': 0.36; 'does': 0.37; 'subject:: ': 0.38; 'object': 0.38; 'to:addr:python.org': 0.39; 'received:192': 0.39; 'list,': 0.39; 'header:Received:5': 0.40; 'your': 0.60; 'range': 0.60; 'special': 0.73 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Skip Montanaro Subject: Re: itertools doc example "consume" Date: Fri, 8 Mar 2013 21:43:21 +0000 (UTC) References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: sea.gmane.org User-Agent: Loom/3.14 (http://gmane.org/) X-Loom-IP: 192.160.124.65 (Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11) 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: 18 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1362779016 news.xs4all.nl 6931 [2001:888:2000:d::a6]:59462 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:40905 Ian Kelly gmail.com> writes: > Depending on your Python version lst is either a range object or a > list, neither of which is an iterator. If you pass to consume an > iterable object that is not an iterator, it will implicitly obtain an > iterator for it, consume from the iterator, and then discard the > iterator, with no effect on the original object. > > In general the itertools functions will work equally well on iterators > and other iterables, but consume is special in that what it does is > only relevant to iterators. Thanks for the explanation. I clearly still need to grapple with this stuff a bit... Skip