Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder1.news.weretis.net!feeder.erje.net!newsfeed.xs4all.nl!newsfeed5.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 0.009 X-Spam-Evidence: '*H*': 0.98; '*S*': 0.00; 'cpython': 0.05; 'important,': 0.07; 'python': 0.10; 'appropriate': 0.15; '3.3,': 0.16; 'between.': 0.16; 'compatible.': 0.16; 'evaluates': 0.16; 'head:': 0.16; 'jython,': 0.16; 'python3': 0.16; 'subject: \n ': 0.16; 'subject:Why': 0.16; 'subject:language': 0.16; 'subject:still': 0.16; 'twisted)': 0.16; 'wrote:': 0.17; 'changes': 0.19; 'windows': 0.20; 'preferred': 0.20; 'separate': 0.20; '2.2': 0.22; '2.x': 0.22; 'header:In-Reply-To:1': 0.23; 'print': 0.25; 'header:User-Agent:1': 0.26; 'language.': 0.27; 'statement': 0.27; 'subject: ?': 0.27; "doesn't": 0.28; '(maybe': 0.29; '3.x': 0.29; 'libraries': 0.29; 'lot.': 0.29; 'this.': 0.29; 'compatible': 0.29; 'function': 0.29; 'fixed': 0.30; '(and': 0.31; 'no,': 0.32; 'could': 0.33; '(e.g.,': 0.33; "aren't": 0.33; 'received:google.com': 0.34; 'implement': 0.35; 'another': 0.35; 'should': 0.35; 'received:209.85': 0.35; 'to:addr:python-list': 0.35; 'list': 0.35; 'version': 0.35; 'there': 0.35; 'does': 0.36; 'but': 0.36; 'possible': 0.37; 'subject:: ': 0.37; 'received:209': 0.37; 'pm,': 0.38; 'supports': 0.38; 'message-id:@gmail.com': 0.38; 'to:addr:python.org': 0.39; 'issues': 0.39; 'header:Received:5': 0.39; 'skip:6 10': 0.61; 'more': 0.63; 'detail.': 0.66; 'fact,': 0.67; 'making': 0.67; 'incoming': 0.70; 'gone': 0.72; 'all;': 0.84; 'someday.': 0.84; 'subject:there': 0.91 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; bh=g4L+LMojrHKpRKtxLKj4faOjaBIisObzJnB43vJfl3Q=; b=oHpAJTDrAMLjS5ZKRi+hlaQUacqtFLX4pfLMtMjLNG8STuqQSSDlUSezZzfEYMwt7h 1S7dNWYZZMeRLk4+u+3xJA67XTrt9Fxyl3fUIj5xrqLyvOOx0ek/+TsGeb6WrUktBVCA NxL7/IsQQqXu5xTMwq4XIKlUjWJgMMhdbdElQMp5HV3XcyFaiwjjR1nelHIBib1CSH/r IR5XV8yFkql1prgQT1+Ljb7fvvM4sNLWPi16uSWli2/XouDUn9q/OmX9IxZGRsfc2hXF vg8qNBdq7qVvaVUyBIx0034p7gkHPXiJJAiWP8m8RZybV2ssxaIawM7yDwP2greMcS5m DX9g== Date: Mon, 25 Jun 2012 03:48:02 -0500 From: Andrew Berg User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: "comp.lang.python" Subject: Re: Why has python3 been created as a seperate language where there is still python2.7 ? References: <1340509604.38915.YahooMailClassic@web164605.mail.gq1.yahoo.com> In-Reply-To: <1340509604.38915.YahooMailClassic@web164605.mail.gq1.yahoo.com> X-Enigmail-Version: 1.4.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.12 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: 33 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1340614104 news.xs4all.nl 6861 [2001:888:2000:d::a6]:39309 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:24423 On 6/23/2012 10:46 PM, gmspro wrote: > What's wrong editing/customizing/changin python2.7 instead of making a > seperate language? py3k is not a separate language. In fact, it is possible to maintain a codebase that supports 2.2 (maybe even older), 3.3, and every version in between. > What's wrong working with python2.7? A lot. Off the top of my head: In 2.7, the print statement has arbitrary and unobvious syntax. The print() function has arguments. In 2.7, input() evaluates incoming strings, which is almost always not appropriate and can lead to exploits. In py3k, input() doesn't do this. It returns exactly what it receives. I barely work with 2.x at all; others will be able to list many more in much more detail. > As python3 is not backward compatible, so many packages built on > python2.7 will be gone someday. Or you have to re-write/upgrade to > python3. That's a tedious/labourious task. Indeed. Backward compatibility is important, but it should not be king. Python had (and arguably still has) major issues that could only be fixed by breaking backward compatibility. AFAIK, people use 2.x mainly because they depend on libraries that are not compatible with py3k yet (e.g., Twisted) or because their preferred implementation does not implement 3.x (e.g., Jython, PyPy). > So after 5 years will we get another python4 as seperate language? No, but there may be changes that aren't backward compatible. -- CPython 3.3.0a4 | Windows NT 6.1.7601.17803