Path: csiph.com!usenet.pasdenom.info!news.albasani.net!rt.uk.eu.org!newsfeed.xs4all.nl!newsfeed2.news.xs4all.nl!xs4all!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; 'python,': 0.02; 'from:addr:yahoo.co.uk': 0.04; 'static': 0.04; 'context': 0.07; 'skip:` 10': 0.07; 'variables': 0.07; 'contexts': 0.09; 'lawrence': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'subject:using': 0.09; 'thus,': 0.09; 'def': 0.12; 'creates': 0.14; 'language.': 0.14; 'ah,': 0.16; 'distinct': 0.16; "function's": 0.16; 'nick': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'roy': 0.16; 'subject:item': 0.16; 'language': 0.16; 'wrote:': 0.18; 'subject:] ': 0.20; 'thanks.': 0.20; 'seems': 0.21; 'feb': 0.22; 'print': 0.22; 'header:User-Agent:1': 0.23; 'closely': 0.24; '---': 0.24; 'post': 0.26; 'header:X-Complaints-To:1': 0.27; 'header:In-Reply-To:1': 0.27; 'url:mailman': 0.30; 'code': 0.31; 'prints': 0.31; 'thanks!': 0.32; 'quite': 0.32; 'url:python': 0.33; 'fri,': 0.33; 'actual': 0.34; 'but': 0.35; '14,': 0.36; 'functions.': 0.36; 'yield': 0.36; 'url:listinfo': 0.36; 'url:org': 0.36; 'should': 0.36; 'too': 0.37; 'two': 0.37; 'to:addr:python-list': 0.38; 'list,': 0.38; 'pm,': 0.38; 'subject:[': 0.39; 'to:addr:python.org': 0.39; 'received:org': 0.40; 'url:mail': 0.40; 'free': 0.61; 'viruses': 0.61; 'protection': 0.63; 'our': 0.64; 'antivirus': 0.68; 'smith': 0.68; 'results': 0.69; 'article': 0.77; 'around,': 0.84; 'forced': 0.84; 'whereas': 0.91 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Mark Lawrence Subject: Re: Generator using item[n-1] + item[n] memory Date: Sat, 15 Feb 2014 12:28:53 +0000 References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: host-78-146-14-108.as13285.net User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 In-Reply-To: X-Antivirus: avast! (VPS 140215-0, 15/02/2014), Outbound message X-Antivirus-Status: Clean 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: 59 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1392467409 news.xs4all.nl 2859 [2001:888:2000:d::a6]:37807 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:66428 On 15/02/2014 03:31, Nick Timkovich wrote: > OK, now the trick; adding `data = None` inside the generator works, but > in my actual code I wrap my generator inside of `enumerate()`, which > seems to obviate the "fix". Can I get it to play nice or am I forced to > count manually. Is that a feature? > > > On Fri, Feb 14, 2014 at 9:21 PM, Roy Smith > wrote: > > In article >, > Nick Timkovich > wrote: > > > Ah, I think I was equating `yield` too closely with `return` in > my head. > > Whereas `return` results in the destruction of the function's > locals, > > `yield` I should have known keeps them around, a la C's `static` > functions. > > Many thanks! > > It's not quite like C's static. With C's static, the static variables > are per-function. In Python, yield creates a context per invocation. > Thus, I can do > > def f(): > for i in range(10000): > yield i > > g1 = f() > g2 = f() > print g1.next() > print g1.next() > print g1.next() > print g2.next() > print g1.next() > > > which prints 0, 1, 2, 0, 3. There's two contexts active at the same > time, with a distinct instance of "i" in each one. > -- > https://mail.python.org/mailman/listinfo/python-list > Nick, please don't top post on this list, thanks. -- My fellow Pythonistas, ask not what our language can do for you, ask what you can do for our language. Mark Lawrence --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com