Path: csiph.com!usenet.pasdenom.info!gegeweb.org!de-l.enfer-du-nord.net!feeder1.enfer-du-nord.net!feeds.phibee-telecom.net!newsfeed.xs4all.nl!newsfeed5.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 0.001 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'subject:: [': 0.03; 'subject:Python': 0.05; 'try:': 0.07; 'python': 0.09; 'files"': 0.09; 'grep': 0.09; 'nameerror:': 0.09; '"grep': 0.16; 'anatoly': 0.16; 'better:': 0.16; 'conversion)': 0.16; 'from:addr:rosuav': 0.16; 'from:name:chris angelico': 0.16; 'hacks': 0.16; 'reload': 0.16; 'subject:ideas': 0.16; 'switch.': 0.16; 'string': 0.17; 'wrote:': 0.17; 'bytes': 0.17; 'else,': 0.17; 'thu,': 0.17; 'code,': 0.18; 'subject:] ': 0.19; 'import': 0.21; 'received:209.85.214.174': 0.21; 'constant': 0.22; 'explicit': 0.22; 'help.': 0.22; 'header:In-Reply-To:1': 0.25; 'am,': 0.27; '(such': 0.27; 'message-id:@mail.gmail.com': 0.27; 'all.': 0.28; 'source': 0.29; 'keyword': 0.30; 'code': 0.31; 'file': 0.32; 'anywhere': 0.33; 'maintained': 0.33; 'to:addr:python-list': 0.33; 'agree': 0.34; 'received:google.com': 0.34; 'consistent': 0.35; 'nov': 0.35; 'received:209.85': 0.35; 'except': 0.36; 'should': 0.36; 'enough': 0.36; 'received:209': 0.37; 'comment': 0.38; 'to:addr:python.org': 0.39; 'received:209.85.214': 0.39; 'easily': 0.39; 'subject:-': 0.40; 'header:Received:5': 0.40; 'most': 0.61; 'remove': 0.61; 'more': 0.63; 'taking': 0.65; 'useful.': 0.65; 'carefully': 0.71; 'unusual': 0.71 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=02cqnbSqH5FvTab0b5xqJTy14X9aU2+vtRLLcW0HT2I=; b=jzt1S0IsjC5AfmVZzP7gYdMW7gc7k/ROxOgycg1JNiGsHC1CqK0L83mNUn5+gln2n2 NSlJMrOw4/dvCMeMgjLd/Z7ZTjjrkVpZR2EhmexbToKmTfDx8y6iz/cdITjJ6dVe8pGC oOqZmQ6k3x+yp3QHA+Z+uJKg9Qhb0M8E82XPTejZ6Y+lGHPanXSd9rjbqn+RzyKaZjK6 ljbys1izcBoxEeHiXPb7i4qqEx8y/tnyFWvh+JkdfzPjxgzlmEtsWi7O8W2j2ZfwsU5c P/nOWlus1hMriL+jm2ZEAWObajOaS4JN3GJpNBYJ9ks0O61iS+evUF/5LFz9Phwk57zt Nywg== MIME-Version: 1.0 In-Reply-To: References: <5096ED46.20502@pearwood.info> <20121105063008.GA14836@ando> Date: Thu, 8 Nov 2012 10:14:35 +1100 Subject: Re: [Python-ideas] sys.py3k From: Chris Angelico To: python-list@python.org 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: 43 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1352330078 news.xs4all.nl 6949 [2001:888:2000:d::a6]:34859 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:32913 On Thu, Nov 8, 2012 at 5:35 AM, anatoly techtonik wrote: > I thought of sys.py3k check as an explicit way to guard the code that should > be maintained extra carefully for Python 3 compatibility, so that you can > grep the source for this constant and remove all the hacks (such as bytes to > string conversion) required to maintain the compatibility when the time > comes to switch. I agree about greppability, it's a huge help. Hence the code comment; as long as you're consistent and you pick a keyword long enough or unusual enough to not occur anywhere else, you can easily do a "find across files" or "grep XYZ *" to find them all. And if you put the comment on the most significant line of code, line-based tools will be more useful. # Unideal: # py3k try: reload except NameError: from imp import reload # Better: try: # py3k reload except NameError: from imp import reload # Best: try: reload # py3k except NameError: from imp import reload # Also best: try: reload except NameError: from imp import reload # py3k Taking just the line with the keyword "py3k" on it will tell you exactly what that file is doing. ChrisA