Error type for shelve.open()

[aomighty at gmail.com]

Yes, the problem was that I hadn't imported anydbm.error... it's
working now.

As for the AttributeError at the end, I talked to someone else, and he
looked at the source and said it was a bug in shelve. I think I will
report it to python.org.

Anyway, thanks :).
Simon Forman wrote:
> aomighty at gmail.com wrote:
> > I tried what you said and it looked like maybe AttributeError, but that
> > didn't work either.
> >
> > This code snippet:
> >
> > import shelve
> > from traceback import format_exc
> >
> > try:
> >    db = shelve.open("meh", "r")
> > except:
> >    print format_exc()
> >
> > Gave me this output:
> > Traceback (most recent call last):
> >   File "test.py", line 5, in ?
> >     db = shelve.open("meh", "r")
> >   File "/usr/lib/python2.4/shelve.py", line 231, in open
> >     return DbfilenameShelf(filename, flag, protocol, writeback, binary)
> >   File "/usr/lib/python2.4/shelve.py", line 212, in __init__
> >     Shelf.__init__(self, anydbm.open(filename, flag), protocol,
> > writeback, binary)
> >   File "/usr/lib/python2.4/anydbm.py", line 77, in open
> >     raise error, "need 'c' or 'n' flag to open new db"
> > error: need 'c' or 'n' flag to open new db
> >
> > Exception exceptions.AttributeError: "DbfilenameShelf instance has no
> > attribute 'writeback'" in  ignored
> >
> > Do you know what the error is?
>
> No.  If you tried catching AttributeError and it didn't work then I'd
> guess that the AttributeError is a secondary result of the initial
> error.
>
> This part of the traceback,
>
> >   File "/usr/lib/python2.4/anydbm.py", line 77, in open
> >     raise error, "need 'c' or 'n' flag to open new db"
> > error: need 'c' or 'n' flag to open new db
>
> indicates that some sort of custom error, probably defined in the
> anydbm.py module.
>
> Catching the execption and binding it to a var,
>
> >>> try:
> ...     db = shelve.open("meh", "r")
> ... except Exception, err:
> ...     E = err
> ...
> Exception exceptions.AttributeError: "DbfilenameShelf instance has no
> attribute 'writeback'" in  ignored
> >>> E
> <anydbm.error instance at 0xb7d8270c>
>
>
>
> So:
> >>> from anydbm import error
> >>> try:
> ...     db = shelve.open("meh", "r")
> ... except error:
> ...     print 'Aha!  got it!'
> ...
> Aha!  got it!
> Exception exceptions.AttributeError: "DbfilenameShelf instance has no
> attribute 'writeback'" in  ignored
>
>
> Well, that catches the error, but I don't know what's going on with the
> additional AttributeError or what to do about it.
> 
> Peace,
> ~Simon