pythonでメタプログラミング

dynamic_typing.py

# https://docs.python.org/3.5/library/types.html
from types import MethodType
class Base(object):
    def __init__(self, **kwargs):
        self.__dict__.update(kwargs)

    def add_instance_method(self, method):
        setattr(self, method.__name__, MethodType(method, self))


p0 = Base(name="zero")
p0.say() # --> AttributeError: 'Base' object has no attribute 'say'


def say(self):
    return "%s: hi." % self.name


p1 = Base(name="taro")
p1.add_instance_method(say)
p1.say() # --> 'taro: hi.'


def say(self):
    return "%s: hello" % self.name


p2 = Base(name="jiro")
p2.add_instance_method(say)
(p1.say(), p2.say()) # --> ('taro: hi.', 'jiro: hello')

https://docs.python.org/3.5/library/types.html