How to bind a constant parameter in Python?

Question

I have got a class similar to

class C:
    def __init__(self, a):
        self.a = a
    def noParam(self):
        return self.a
    def withParam(self, b)
            


        

Answer 1

You want to use functools.partial:

import functools

instC = C(5.)
meth = functools.partial(instC.withParam, 239)

Then you can pass this method (bound with both your instance and the value 239):

do_thing(meth)

Answer 2

You can use lambda functions to bind parameters:

meth = lambda: instC.withParam(239)