Path: csiph.com!usenet.pasdenom.info!gegeweb.org!de-l.enfer-du-nord.net!feeder1.enfer-du-nord.net!tudelft.nl!txtfeed1.tudelft.nl!multikabel.net!newsfeed20.multikabel.net!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; 'context': 0.04; 'args': 0.05; 'instance,': 0.05; 'attribute': 0.07; 'exception,': 0.07; 'python': 0.08; '>>>>': 0.09; 'subclasses': 0.09; 'exception': 0.12; 'win32': 0.12; 'def': 0.13; "'a'": 0.16; '*args):': 0.16; 'a()': 0.16; 'a.x': 0.16; 'handy': 0.16; 'self,': 0.16; 'subject:instance': 0.16; 'cc:addr:python-list': 0.16; 'wrote:': 0.18; '>>>': 0.18; 'instance': 0.18; 'seems': 0.20; '(most': 0.21; 'to:2**1': 0.21; 'header:In-Reply-To:1': 0.22; 'dec': 0.22; 'string': 0.24; 'traceback': 0.24; 'cc:2**0': 0.26; 'classes': 0.26; 'looks': 0.27; 'not.': 0.28; 'mine': 0.28; 'bit': 0.28; 'message-id:@mail.gmail.com': 0.29; 'see,': 0.29; 'class': 0.29; 'print': 0.29; 'cc:addr:python.org': 0.29; 'pm,': 0.29; 'behaves': 0.30; 'str': 0.30; 'use?': 0.30; 'on,': 0.31; 'version': 0.32; 'instead.': 0.32; 'thu,': 0.32; 'there': 0.33; 'object': 0.33; 'test': 0.34; 'file': 0.34; 'normally': 0.34; 'last):': 0.34; 'subject:getting': 0.34; '...': 0.35; 'something': 0.35; 'but': 0.37; 'received:google.com': 0.37; 'skip:_ 10': 0.38; 'received:209.85': 0.38; 'think': 0.38; 'listed': 0.38; 'getting': 0.38; 'received:209': 0.39; 'here': 0.64; 'account': 0.66; 'taking': 0.66; '2.7.': 0.84; 'difference.': 0.84; 'so:': 0.84 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; bh=ysgjXxJFVYg0IoRLqxwTOvtH8N+6k9uO0f8HWSKkcvY=; b=ClVUaSa8YOHmJ/O7LNUx2jc+yzE/VBMphVXF8IF22k4S+FQUVF9aX4lT3U2tZcwnU+ kBYyAyA01UAGjjS8Iy3/AfwUf6jM2aZQXGDeLayqx1f0s66mlStSgMtnBflM2TkeyVIZ JQQhZb0MHQpOshhh4Jx60OpwQ11Z6yGwHhkUqulRetSFTeVo6cCY3CVjXg0TMqDnMpYe Tybyrf7+sTjWmUuKCqVjoqS3htaEF4+6VJplbWDcP6vZn6bvYf7mVCNenMhsoA0abCwe 4CEKqbtHG5em0cjdPvCc6l1nHOo5/5+iWS5uvN6IGcu8f79qR64WbrX7U78A18BPm3G7 7ZRQ== MIME-Version: 1.0 In-Reply-To: <5B80DD153D7D744689F57F4FB69AF474026B9625@SCACMX008.exchad.jpmchase.net> References: <5B80DD153D7D744689F57F4FB69AF474026B9264@SCACMX008.exchad.jpmchase.net> <5B80DD153D7D744689F57F4FB69AF474026B9625@SCACMX008.exchad.jpmchase.net> From: Ian Kelly Date: Thu, 15 Mar 2012 13:49:02 -0600 Subject: Re: Context Manager getting str instead of AttributeError instance To: "Prasad, Ramit" Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable 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: 56 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1331840975 news.xs4all.nl 6962 [2001:888:2000:d::a6]:36292 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:21708 On Thu, Mar 15, 2012 at 1:10 PM, Prasad, Ramit wrote: >> Prasad, Ramit wrote: >> >> > So I have a context manager used to catch errors >> > >> > def __exit__( self, exceptionClass, exception, tracebackObject ): >> > =A0 =A0 if isinstance( exception, self.exceptionClasses ): >> > =A0 =A0 =A0 =A0 =A0#do something here >> > >> > Normally exception would be the exception instance, but for >> > AttributeError it seems to be a string instead. >> >> I don't think so: >> >> >>> class A(object): >> ... =A0 =A0 def __enter__(self): return self >> ... =A0 =A0 def __exit__(self, *args): print args >> ... >> >>> with A() as a: >> ... =A0 =A0 a.x >> ... >> (, AttributeError("'A' object has no >> attribute 'x'",), ) >> Traceback (most recent call last): >> =A0 File "", line 2, in >> AttributeError: 'A' object has no attribute 'x' >> >> > 1) Why is AttributeError different than the other built-ins >> > in this respect? >> > 2) Are there other standard errors like this (I know >> > that SystemExit is different as well)? >> > 3) Taking into account that I want to include subclasses of >> > classes listed in self.exceptionClasses, Is there a better check I can >> > use? > > Not sure why mine behaves differently: > Python 2.6.6 (r266:84292, Dec 17 2010, 12:36:53) [MSC v.1500 32 bit (Inte= l)] on win32 >>>> >>>> class A(object): > ... =A0 =A0 def __enter__(self): return self > ... =A0 =A0 def __exit__(self, *args): print args > ... >>>> with A() as a: > ... =A0 =A0 a.x > ... > (, "'A' object has no attribute 'x'", <= traceback object at 0x1817F648>) > AttributeError: 'A' object has no attribute 'x' > > As you can see, I am getting a string while you are not. Looks like a version difference. I don't have Python 2.6 handy to test on, but I get a str in Python 2.5 and an AttributeError instance in Python 2.7.