Hi Mark, On 10 December 2011 17:54, Mark Lybrand <mlybr...@gmail.com> wrote: > > I am working on the Files chapter of Dive into Python 3, and have implemented > the example script at the end of this message. The first input prints to the > terminal as expected, the second value prints to the file as expected. Then > the script tries to destroy in the class instance and bombs with: > > TypeError: __exit__() takes exactly 1 positional argument (4 given) > Exception ValueError: 'I/O operation on closed file.' in <_io.TextIOWrapper > name > ='out.log' mode='w' encoding='utf-8'> ignored > > and the final input is, naturally, never printed. > > Is the example wrong, or is this something to do with how Windows handles > stdout that is causing this not to work as designed? I am using Python 3.2 > on Windows Vista Home Premium.
It seems the example may be wrong -- the __exit__ method, as stated by the error, is being given 4 parameters whereas the one defined in the code only expects one. I've looked an this is correct on Python 3.2 that I have on Windows as well. Perhaps the implementation of __exit__ has been changed somewhere and had the paramters added and the book is just out of date? In any case, changing the def __exit__ line to: def __exit__(self, type, value, traceback): ... will fix the problem. Cheers Walter _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
