From 754bbf7a25a8dda49b5d08ef0d0443bbf5af0e36 Mon Sep 17 00:00:00 2001 From: Craig Jennings Date: Sun, 7 Apr 2024 13:41:34 -0500 Subject: new repository --- devdocs/python~3.12/library%2Fcopyreg.html | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 devdocs/python~3.12/library%2Fcopyreg.html (limited to 'devdocs/python~3.12/library%2Fcopyreg.html') diff --git a/devdocs/python~3.12/library%2Fcopyreg.html b/devdocs/python~3.12/library%2Fcopyreg.html new file mode 100644 index 00000000..42c6898c --- /dev/null +++ b/devdocs/python~3.12/library%2Fcopyreg.html @@ -0,0 +1,27 @@ +

copyreg — Register pickle support functions

Source code: Lib/copyreg.py

The copyreg module offers a way to define functions used while pickling specific objects. The pickle and copy modules use those functions when pickling/copying those objects. The module provides configuration information about object constructors which are not classes. Such constructors may be factory functions or class instances.

+copyreg.constructor(object)
+

Declares object to be a valid constructor. If object is not callable (and hence not valid as a constructor), raises TypeError.

+
+copyreg.pickle(type, function, constructor_ob=None)
+

Declares that function should be used as a “reduction” function for objects of type type. function must return either a string or a tuple containing between two and six elements. See the dispatch_table for more details on the interface of function.

The constructor_ob parameter is a legacy feature and is now ignored, but if passed it must be a callable.

Note that the dispatch_table attribute of a pickler object or subclass of pickle.Pickler can also be used for declaring reduction functions.

+

Example

The example below would like to show how to register a pickle function and how it will be used:

>>> import copyreg, copy, pickle
+>>> class C:
+...     def __init__(self, a):
+...         self.a = a
+...
+>>> def pickle_c(c):
+...     print("pickling a C instance...")
+...     return C, (c.a,)
+...
+>>> copyreg.pickle(C, pickle_c)
+>>> c = C(1)
+>>> d = copy.copy(c)  
+pickling a C instance...
+>>> p = pickle.dumps(c)  
+pickling a C instance...
+
+

+ © 2001–2023 Python Software Foundation
Licensed under the PSF License.
+ https://docs.python.org/3.12/library/copyreg.html +

+
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