Path: csiph.com!usenet.pasdenom.info!gegeweb.org!de-l.enfer-du-nord.net!feeder2.enfer-du-nord.net!cs.uu.nl!news.stack.nl!newsfeed.xs4all.nl!newsfeed1.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 0.107 X-Spam-Level: * X-Spam-Evidence: '*H*': 0.79; '*S*': 0.00; 'referring': 0.07; 'thread,': 0.09; 'simple.': 0.16; 'subject:search': 0.16; 'wrote:': 0.17; 'feb': 0.19; 'earlier': 0.21; 'work,': 0.22; 'header:In-Reply-To:1': 0.25; 'am,': 0.27; 'message- id:@mail.gmail.com': 0.27; "doesn't": 0.28; 'subject:/': 0.28; "d'aprano": 0.29; 'steven': 0.29; 'worked': 0.30; 'fri,': 0.30; 'surely': 0.33; 'to:addr:python-list': 0.33; 'received:google.com': 0.34; 'received:209.85': 0.35; 'characters': 0.36; 'depends': 0.36; 'being': 0.37; 'received:209': 0.37; 'data': 0.37; 'subject:: ': 0.38; 'to:addr:python.org': 0.39; 'skip:" 10': 0.40; 'six': 0.65; 'applying': 0.69; 'hand': 0.82; '2013': 0.84; 'subject:via': 0.84; 'sweeping': 0.84; 'to:name:python': 0.84 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:mime-version:in-reply-to:references:from:date:message-id :subject:to:content-type; bh=dM9dM9bpM7C/QrFT4JbwE1onKUkfo/gjQsC8VrfS4CI=; b=Km7QxYacDAtu5sHPvGNY/xj+Aeu3hBlTFXsP2fClaYWH55SNgq8tYuvjquxR2yxnwN gKr80vbpDQaM6kSqvjivvxShEyNPZKBI49r4Nc5z20Hl1F+96cVaUBd5kTLnxzWECs8f mEFwLH/mHgruE/RaLOgquZRH//kvQvRB7L/vcbeHe4gz3QnN5USvX3+FA7mx4cf9zuWv MOAz23z1XEpt1Eq7gJwjbaCPJ9RiwuWPDFVOs/S4WCBoC6jvNlFBpiiMkbQSUG5wCHlU Y8T+RRisTIaLa8CibzQrSSa19mmwj6DWYrYklBTqar5AaWd4GkfgFDgWsZ8tlhzqUPOT XhrQ== X-Received: by 10.66.52.50 with SMTP id q18mr18933982pao.16.1360340858594; Fri, 08 Feb 2013 08:27:38 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <5114e4c8$0$29975$c3e8da3$5496439d@news.astraweb.com> References: <511319c7$0$21812$c3e8da3$76491128@news.astraweb.com> <51142e96$0$6512$c3e8da3$5496439d@news.astraweb.com> <51143feb$0$29974$c3e8da3$5496439d@news.astraweb.com> <20130207215755.3c4a5c464357313496320cc3@lavabit.com> <5114e4c8$0$29975$c3e8da3$5496439d@news.astraweb.com> From: Ian Kelly Date: Fri, 8 Feb 2013 09:26:58 -0700 Subject: Re: Curious to see alternate approach on a search/replace via regex To: Python Content-Type: text/plain; charset=ISO-8859-1 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: 20 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1360341326 news.xs4all.nl 6965 [2001:888:2000:d::a6]:44488 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:38463 On Fri, Feb 8, 2013 at 4:43 AM, Steven D'Aprano wrote: > Ian Kelly wrote: > Surely that depends on the size of the pattern, and the size of the data > being worked on. Natually. > Compiling the pattern "s[ai]t" doesn't take that much work, it's only six > characters and very simple. Applying it to: > > "sazsid"*1000000 + "sat" > > on the other hand may be a tad expensive. > > Sweeping generalities about the cost of compiling regexes versus searching > with them are risky. I was referring to the specific timing measurements I made earlier in this thread, not generalizing.