On Tue, 31 Jan 2012 15:09:34 -0700, Ian Kelly wrote: > On Tue, Jan 31, 2012 at 2:07 PM, Prasad, Ramit > <ramit.pra...@jpmorgan.com> wrote: >>>Like Neil mentioned, a contextmanager generator is wrapped with an >>>__exit__ method that is guaranteed to be called and that explicitly >>>resumes or closes the generator. So as long as your contextmanager >>>generator is properly written (i.e. it yields exactly once), the >>>finally block will execute in a timely fashion. >> >> Is that true even in the face of something like sys.exit()? > > Yes. [...] > You can certainly come up with scenarios in which the finally clause > does not execute, e.g. killing the interpreter with "kill -9" or yanking > out the power cord. Within the confines of the Python interpreter, > though, it is guaranteed that the finally block will execute.
Almost, but not quite. The finally block is not guaranteed to execute if the try block never exits -- infinite loops are still infinite loops. Also, unlike sys.exit, os._exit doesn't work through the exception mechanism, can't be caught, and simply exits immediately. >>> import os >>> try: ... os._exit(1) ... finally: ... print "exiting" ... steve@runes:~$ -- Steven -- http://mail.python.org/mailman/listinfo/python-list
