Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!xlned.com!feeder3.xlned.com!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; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'python': 0.11; 'def': 0.12; 'count,': 0.16; 'itertools': 0.16; 'lambda': 0.16; 'received:80.91.229.3': 0.16; 'received:dip0.t-ipconnect.de': 0.16; 'received:plane.gmane.org': 0.16; 'received:t-ipconnect.de': 0.16; 'renamed': 0.16; 'subject:generator': 0.16; 'true:': 0.16; 'wrote:': 0.18; 'import': 0.22; 'header:User-Agent:1': 0.23; 'replace': 0.24; 'header:X-Complaints-To:1': 0.27; 'function': 0.29; 'probably': 0.32; 'but': 0.35; 'yield': 0.36; 'thank': 0.38; 'filter': 0.38; 'to:addr:python-list': 0.38; 'to:addr:python.org': 0.39; 'received:org': 0.40; 'expression': 0.60; 'gone': 0.61; 'andrea': 0.84; 'nice,': 0.84 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Peter Otten <__peter__@web.de> Subject: Re: generator slides review Date: Sun, 02 Feb 2014 13:47:06 +0100 Organization: None References: <8118b17c-3352-4832-8567-089bd14c21ce@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7Bit X-Gmane-NNTP-Posting-Host: p5084bc76.dip0.t-ipconnect.de User-Agent: KNode/4.7.3 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: 36 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1391345206 news.xs4all.nl 2916 [2001:888:2000:d::a6]:43701 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:65261 andrea crotti wrote: > 2014-02-01 Miki Tebeka : >> >> My 2 cents: >> slide 21: >> from itertools import count, ifilterfalse >> >> def divided_by(p): >> return lambda n: n % p == 0 >> >> def primes(): >> nums = count(2) >> while True: >> p = next(nums) >> yield p >> nums = ifilterfalse(divided_by(p), nums) >> > > Thank you that's nicer, It may be nice, but is probably less efficient because of the lambda function calls that replace the if expression in your > def exclude_multiples(n, ints): > for i in ints: > if (i % n) != 0: > yield i > but ifiilterfalse is not in Python 3 (could > use filter of course). ifilterfalse() isn't gone in Python3, it just was renamed to filterfalse().