Prasad, Ramit wrote: >> Prasad, Ramit wrote: >> >> > So I have a context manager used to catch errors >> > >> > def __exit__( self, exceptionClass, exception, tracebackObject ): >> > if isinstance( exception, self.exceptionClasses ): >> > #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): >> ... def __enter__(self): return self >> ... def __exit__(self, *args): print args >> ... >> >>> with A() as a: >> ... a.x >> ... >> (<type 'exceptions.AttributeError'>, AttributeError("'A' object has no >> attribute 'x'",), <traceback object at 0x7f57b70f22d8>) >> Traceback (most recent call last): >> File "<stdin>", line 2, in <module> >> 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 > (Intel)] on win32 >>>> >>>> class A(object): > ... def __enter__(self): return self > ... def __exit__(self, *args): print args > ... >>>> with A() as a: > ... a.x > ... > (<type 'exceptions.AttributeError'>, "'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.
Ah, it's a bug: http://bugs.python.org/issue7853 Unfortunately it is to severe to fix in a bugfix release. You could work around it with an issubclass() test on the first argument. -- http://mail.python.org/mailman/listinfo/python-list