cpython/Lib/copy_reg.py
Fred Drake 78a6a36964 In the module docstring, clarify that this is used to register pickle
support for extension types, not classes.

pickle():  If the type is a class or if the reduction function is not
           callable, raise a TypeError.

constructor():  If the constructor is not callable, raise TypeError.

This (partially) closes SourceForge patch #101859.
2000-10-11 22:16:45 +00:00

34 lines
964 B
Python

"""Helper to provide extensibility for pickle/cPickle.
This is only useful to add pickle support for extension types defined in
C, not for instances of user-defined classes.
"""
from types import ClassType as _ClassType
dispatch_table = {}
safe_constructors = {}
def pickle(ob_type, pickle_function, constructor_ob=None):
if type(ob_type) is _ClassType:
raise TypeError("copy_reg is not intended for use with classes")
if not callable(pickle_function):
raise TypeError("reduction functions must be callable")
dispatch_table[ob_type] = pickle_function
if constructor_ob is not None:
constructor(constructor_ob)
def constructor(object):
if not callable(object):
raise TypeError("constructors must be callable")
safe_constructors[object] = 1
# Example: provide pickling support for complex numbers.
def pickle_complex(c):
return complex, (c.real, c.imag)
pickle(type(1j), pickle_complex, complex)