On Fri, 10 May 2013 17:59:26 +0100, Nobody wrote: > On Thu, 09 May 2013 05:23:59 +0000, Steven D'Aprano wrote: > >> There is no sensible use-case for creating a file without opening it. >> What would be the point? Any subsequent calls to just about any method >> will fail. Since you have to open the file after creating the file >> object anyway, why make them two different calls? > > As a counterpoint, some OSes (e.g. Plan 9) allow you to get a "handle" > to a file without opening it. This can then be used for deleting, > renaming or stat()-type operations without either the risk of race > conditions (if another process renames files between operations, the > operations may be performed on different files) or the side-effects of > actually opening the file (particularly for device files, e.g. opening a > tape drive may rewind the tape).
Ah, now that's a fantastic counter-example. But I think that says more about the primitiveness of the Unix file model than of the idea of temporal coupling. > Python's file model doesn't allow for this, so there isn't really > anything meaningful that you can do on a file object which isn't open > (although these actually exist; any file object on which the .close() > method has been called will be in this state). Absolutely correct, and I'm amazed it's taken this long for anyone to point this out :-) -- Steven -- http://mail.python.org/mailman/listinfo/python-list
