Popular recipes tagged "metaclasses" but not "algorithms"

dynamically changing encoder (for json) with metaclass (class factory) (Python)

2013-10-24T11:31:44-07:00

Python recipe 578696 by - (class_factory, encode, json, metaclass, metaclasses).

The json.dumps need to be feed with some class (cls =someClass) but what if we want to change the class dynamically? This example can be done by declaring the listOfClasses in class level of course, but the idea is to be changeable. This can be done by the class factory function encoderFacory

Bless Classes into Singletons (Python)

2011-09-21T05:34:52-07:00

Python recipe 577875 by Anand B Pillai (metaclasses, patterns, singleton).

A pattern using metaclasses for "blessing" classes into Singletons.

Using Metaclasses and Class Decorators to Inherit Function Docstrings (Python)

2011-06-11T00:59:35-07:00

Python recipe 577743 by Eric Snow (decorator, decorators, docstring, inheritance, metaclass, metaclasses). Revision 4.

You'll find three different approaches to copying the method's docstring to the overriding method on a child class.

The function decorator approach is limited by the fact that you have to know the class when you call the decorator, so it can't be used inside a class body. However, recipe #577746 provides a function decorator that does not have this limitation.