DL Neil wrote:
Is there a technique or pattern for taking a (partially-) populated instance of a class, and re-creating it as an instance of one of its sub-classes?
Often you can assign to the __class__ attribute of an instance to change its class. Python 3.7.3 (default, Apr 8 2019, 22:20:19) [GCC 4.2.1 (Apple Inc. build 5664)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> class Person: ... pass ... >>> class Male(Person): ... pass ... >>> p = Person() >>> p.__class__ = Male >>> isinstance(p, Male) True >>> You would then be responsible for initialising any attributes of Male that Person didn't have. -- Greg -- https://mail.python.org/mailman/listinfo/python-list
