Peter Otten
12/19/2007 9:15:00 AM
Dmitry Teslenko wrote:
> Hello!
> I've made some class that can be used with "with statement". It looks this way:
>
> class chdir_to_file( object ):
> ...
> def __enter__(self):
> ...
>
> def __exit__(self, type, val, tb):
> ...
> def get_chdir_to_file(file_path):
> return chdir_to_file(file_path)
> ...
>
> Snippet with object instantiation looks like this:
> for s in sys.argv[1:]:
> c = chdir_to_file( s )
> with c:
> print 'Current directory is %s' % os.path.realpath( os.curdir )
>
> That works fine. I want to enable it to be used in more elegant way:
> for s in ... :
> with get_chdir_to_file( s ) as c:
> c.do_something()
>
> But python complains c is of NoneType and has no "do_something()". Am
> I missing something?
Does the chdir_to_file class have a do_something() method? If so,
changing chdir_to_file.__enter__() to
def __enter__(self):
# ...
return self
should help.
Peter