On Sun, 18 Sept 2022 at 07:20, Ralf M. <ral...@t-online.de> wrote: > > Am 16.09.2022 um 23:34 schrieb Eryk Sun: > > On 9/16/22, Ralf M. <ral...@t-online.de> wrote: > >> I would like to replace a method of an instance, but don't know how to > >> do it properly. > > > > A function is a descriptor that binds to any object as a method. For > > example: > > > > >>> f = lambda self, x: self + x > > >>> o = 42 > > >>> m = f.__get__(o) > > >>> type(m) > > <class 'method'> > > >>> m.__self__ is o > > True > > >>> m(10) > > 52 > > Thank you and Chris A. for the two suggestions how to replace a method. > > I tried both > inst.method = functools.partial(new_method, inst) > and > inst.method = new_method.__get__(inst) > and both work in my toy example. > I will try it on the real code next week. > > Even though the functools.partial solution is easier to understand (at > least for me), I will probably use the __get__ solution as it avoids > the import of an extra library. >
The two are basically equivalent. Using functools.partial emphasizes the fact that all you're doing is "locking in" the first parameter; using the __get__ method emphasizes the fact that functions are, fundamentally, the same thing as methods. Choose whichever one makes sense to you! ChrisA -- https://mail.python.org/mailman/listinfo/python-list
