Path: csiph.com!usenet.pasdenom.info!news.albasani.net!newsfeed.freenet.ag!news2.euro.net!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 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'encoding': 0.05; 'subject:Python': 0.06; 'skip:` 10': 0.07; 'apis': 0.09; 'from:addr:ethan': 0.09; 'from:addr:stoneleaf.us': 0.09; 'from:name:ethan furman': 0.09; 'message-id:@stoneleaf.us': 0.09; 'received:184.172': 0.09; 'received:gator410.hostgator.com': 0.09; 'strings.': 0.09; 'subject:design': 0.09; 'subject:skip:c 10': 0.09; '~ethan~': 0.09; 'runs': 0.10; 'api': 0.11; 'python': 0.11; 'api,': 0.16; 'backward': 0.16; 'bump': 0.16; 'cleaner': 0.16; 'expects': 0.16; 'schwarzer': 0.16; 'subject:API': 0.16; 'underlying': 0.16; 'wrote:': 0.18; 'stefan': 0.19; 'version.': 0.19; 'header:User-Agent:1': 0.23; 'byte': 0.24; 'unicode': 0.24; 'regardless': 0.24; 'developers': 0.25; '(see': 0.26; 'switch': 0.26; 'header:In-Reply-To:1': 0.27; 'am,': 0.29; "doesn't": 0.30; 'returned': 0.30; 'program,': 0.31; 'code': 0.31; 'text': 0.33; 'version': 0.36; 'charset:us-ascii': 0.36; 'remote': 0.38; 'to:addr:python-list': 0.38; 'files': 0.38; 'supporting': 0.39; 'to:addr:python.org': 0.39; 'major': 0.40; 'subject: / ': 0.60; 'break': 0.61; 'received:173': 0.61; 'back': 0.62; 'kind': 0.63; 'different': 0.65; 'behavior': 0.77; 'reading,': 0.84 Date: Sat, 13 Apr 2013 11:03:15 -0700 From: Ethan Furman User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: python-list@python.org Subject: Re: API design for Python 2 / 3 compatibility References: <51698989.2070805@sschwarzer.net> In-Reply-To: <51698989.2070805@sschwarzer.net> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator410.hostgator.com X-AntiAbuse: Original Domain - python.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - stoneleaf.us X-BWhitelist: no X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: ([173.12.184.235]) [173.12.184.235]:55805 X-Source-Auth: ethan+stoneleaf.us X-Email-Count: 1 X-Source-Cap: dG9idWs7dG9idWs7Z2F0b3I0MTAuaG9zdGdhdG9yLmNvbQ== 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: 31 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1365877587 news.xs4all.nl 2563 [2001:888:2000:d::a6]:54340 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:43535 On 04/13/2013 09:36 AM, Stefan Schwarzer wrote: > * Approach 2 > > When opening remote text files for reading, ftputil will > always return unicode strings from `read(line/s)`, > regardless of whether it runs under Python 2 or Python 3. > > Pro: Uniform API, independent on underlying Python > version. > > Pro: Supporting a single API will result in cleaner code > in ftputil than when supporting different APIs (see > above). > > Con: This approach might break some code which expects > the returned strings under Python 2 to be byte strings. > > Con: Developers who only use Python 2 might be confused > if ftputil returns unicode strings from `read(line/s)` > since this behavior doesn't match files opened with > `open` in Python 2. > > Which approach do you recommend and why do you prefer that > approach? Approach 2, because it is much saner to deal with unicode inside the program, and only switch back to some kind of encoding when writing to files/pipes/etc. Since you are going to support python 3 as well you can bump the major version number and note the backward incompatibility. -- ~Ethan~