diff options
Diffstat (limited to 'Doc/library/weakref.rst')
| -rw-r--r-- | Doc/library/weakref.rst | 23 |
1 files changed, 7 insertions, 16 deletions
diff --git a/Doc/library/weakref.rst b/Doc/library/weakref.rst index 5b5e460..818a6fa 100644 --- a/Doc/library/weakref.rst +++ b/Doc/library/weakref.rst @@ -529,22 +529,13 @@ follows:: def __del__(self): self.remove() -This solution has a couple of serious problems: - -* There is no guarantee that the object will be garbage collected - before the program exists, so the directory might be left. This is - because reference cycles containing an object with a :meth:`__del__` - method can never be collected. And even if the :class:`TempDir` - object is not itself part of a reference cycle, it may still be kept - alive by some unkown uncollectable reference cycle. - -* The :meth:`__del__` method may be called at shutdown after the - :mod:`shutil` module has been cleaned up, in which case - :attr:`shutil.rmtree` will have been replaced by :const:`None`. - This will cause the :meth:`__del__` method to fail and the directory - will not be removed. - -Using finalizers we can avoid these problems:: +This solution has a serious problem: the :meth:`__del__` method may be +called at shutdown after the :mod:`shutil` module has been cleaned up, +in which case :attr:`shutil.rmtree` will have been replaced by :const:`None`. +This will cause the :meth:`__del__` method to fail and the directory +will not be removed. + +Using finalizers we can avoid this problem:: class TempDir: def __init__(self): |