Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!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 0.005 X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'root': 0.05; 'tries': 0.07; 'string': 0.09; 'agree,': 0.09; 'escape': 0.09; 'semantic': 0.09; 'python': 0.11; '>the': 0.16; 'advantage.': 0.16; 'codebases.': 0.16; 'from:addr:cs': 0.16; 'from:addr:zip.com.au': 0.16; 'from:name:cameron simpson': 0.16; 'hmm.': 0.16; 'message- id:@cskk.homeip.net': 0.16; 'oppose': 0.16; 'portable': 0.16; 'record,': 0.16; 'simpson': 0.16; 'exception': 0.16; 'fix': 0.17; 'wrote:': 0.18; '(but': 0.19; 'machine': 0.22; 'to:name:python- list@python.org': 0.22; 'header:User-Agent:1': 0.23; 'cheers,': 0.24; 'header:In-Reply-To:1': 0.27; 'chris': 0.29; 'then.': 0.30; 'work.': 0.31; 'code': 0.31; '(usually': 0.31; 'exceptions': 0.31; 'class': 0.32; 'run': 0.32; 'guess': 0.33; 'could': 0.34; 'subject:with': 0.35; "can't": 0.35; 'common': 0.35; 'but': 0.35; 'add': 0.35; 'there': 0.35; 'charset:us-ascii': 0.36; "i'll": 0.36; 'bringing': 0.38; 'to:addr:python-list': 0.38; 'that,': 0.38; 'recent': 0.39; 'does': 0.39; 'to:addr:python.org': 0.39; 'how': 0.40; 'remove': 0.60; 'catch': 0.60; 'truly': 0.60; 'content-disposition:inline': 0.62; 'believe': 0.68; 'bare': 0.84; 'confusing': 0.84; 'everything.': 0.84; 'received:192.168.15': 0.84; 'subject:..': 0.84; 'why?': 0.91 Date: Sun, 12 Apr 2015 07:37:34 +1000 From: Cameron Simpson To: "python-list@python.org" Subject: Re: try..except with empty exceptions MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) References: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.20 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: 32 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1428788263 news.xs4all.nl 2945 [2001:888:2000:d::a6]:50642 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:88843 On 11Apr2015 21:21, Chris Angelico wrote: >But I agree, it would be very nice if Python 3 could have abolished >the truly confusing part of this, where "except:" catches everything. >Forcing people to spell it "except BaseException:" would fix all of >this. How hard is it to deprecate and then remove that, same as string >exceptions were removed? I guess I'll go over there to oppose it then. Why? It makes it harder to write portable python 2/3 code and does not add any semantic advantage. Unless there's a common root exception class in Python 2, which I believe there isn't, you can't catch all exceptions in python 2 without the "except:" syntax. Which means the _only_ way to have some code in both 2 and 3 that does it requires 2 codebases. As one who tries to have his code run in both 2 (usually recent 2, like 2.6/2.7) and 3, this change would cause a signification breakage for me without bringing any semantic benefits. Without vigorous use of the time machine I don't see a fix here. For the record, I would be ok (but not "for") never having had bare "except" if all exceptions had always had a common root. Hmm. Can I catch "object"? Sounds awful, but might work. Cheers, Cameron Simpson EMACS: Escape Meta Alt Control Shift