def __deepcopy__(self, memo=None):
"""
- WARNING: If any of the lazy items contains a bound method then it's
- typical for deepcopy() to raise an exception like this:
-
- File "/usr/lib/python2.5/copy.py", line 189, in deepcopy
- y = _reconstruct(x, rv, 1, memo)
- File "/usr/lib/python2.5/copy.py", line 322, in _reconstruct
- y = callable(*args)
- File "/usr/lib/python2.5/copy_reg.py", line 92, in __newobj__
- return cls.__new__(cls, *args)
- TypeError: instancemethod expected at least 2 arguments, got 0
-
- If deepcopy() needs to work, this problem can be avoided by
- implementing lazy items with normal (non-bound) functions.
-
- If deepcopy() raises a TypeError for a lazy item that has been added
- via a call to addLazySingleton(), the singleton will be automatically
- evaluated and deepcopy() will instead be called on the result.
+ This forces evaluation of each contained lazy item, and deepcopy of
+ the result. A TypeError is raised if any contained lazy item is not
+ a singleton, since it is not necessarily possible for the behavior
+ of this type of item to be safely preserved.
"""
if memo is None:
memo = {}