Path: csiph.com!x330-a1.tempe.blueboxinc.net!newsfeed.hal-mli.net!feeder3.hal-mli.net!newsfeed.hal-mli.net!feeder1.hal-mli.net!news.stack.nl!newsfeed.xs4all.nl!newsfeed6.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 0.043 X-Spam-Evidence: '*H*': 0.91; '*S*': 0.00; 'imports': 0.07; 'lost.': 0.09; 'circular': 0.15; 'altogether.': 0.16; 'nail': 0.16; 'refactoring': 0.16; 'uncommon': 0.16; 'cc:addr:python-list': 0.16; 'wrote:': 0.18; 'subject:Question': 0.19; 'cc:no real name:2**0': 0.21; 'trying': 0.21; 'header:In-Reply-To:1': 0.22; 'cc:2**0': 0.26; 'module': 0.26; 'code': 0.26; 'import': 0.27; 'rid': 0.29; 'cc:addr:python.org': 0.29; 'seem': 0.29; 'there': 0.33; 'header:User-Agent:1': 0.33; 'all.': 0.34; 'anything': 0.34; 'something': 0.35; 'question': 0.36; 'but': 0.37; 'doing': 0.38; 'think': 0.38; 'possible,': 0.39; 'except': 0.39; "you've": 0.61; 'address': 0.61; 'frank': 0.64; 'battle': 0.84; 'outset': 0.84; 'unavoidable': 0.84; 'recurring': 0.93 X-IronPort-AV: E=Sophos;i="4.73,491,1325458800"; d="scan'208";a="194797" X-Virus-Scanned: amavisd-new at zimbra.sequans.com Date: Mon, 27 Feb 2012 15:59:52 +0100 From: Jean-Michel Pichavant User-Agent: Mozilla-Thunderbird 2.0.0.24 (X11/20100328) MIME-Version: 1.0 To: Frank Millman Subject: Re: Question about circular imports References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: python-list@python.org 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: 29 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1330354794 news.xs4all.nl 6871 [2001:888:2000:d::a6]:60334 X-Complaints-To: abuse@xs4all.nl Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:20942 Frank Millman wrote: > Hi all > > I seem to have a recurring battle with circular imports, and I am trying to > nail it once and for all. > > Let me say at the outset that I don't think I can get rid of circular > imports altogether. It is not uncommon for me to find that a method in > Module A needs to access something in Module B, and a method in Module B > needs to access something in Module A. I know that the standard advice is to > reorganise the code to avoid this, and I try to do this where possible, but > for now I would like to address the question of how to handle the situation > if this is otherwise unavoidable. > Hi Frank, If you consider it unavoidable you've already lost. There is no reliable solution to circular import except refactoring the code to place all common code elsewhere: wavbase.py wavread.py (import wavbase) wavwrite.py (import wavbase) Any code required by both waread and wavwrite would end up in wavbase. Is there anything that prevent you from doing this ? JM