Question

This question is specifically in the context of Python classes here, but could be more generalized. I am creating a class m that will be initialized with four variables, which I would then like to assign to the instantiation of the class. Right now, this looks like this:

class mm(object):
  def __init__(self, a, b, c, r):
    self.a = a
    self.b = b
    self.c = c
    self.r = r
  # etc.

However, I would like to be able to assign the variables to self in one line, something like the pseudocode:

def __init__(self, a, b, c, r):
  self.varname = var for var in [a, b, c, r]

It would be even better if this could be generalized to an arbitrary number of variables, so that you could get something like:

def __init__(self, **kwargs):
  assign(self, varname, value) for varname, value in kwargs.iteritems()

However, as far as I know, it’s not really possible to loop through statements like that. Does anyone know a way to do this?

Answer 1

You can use setattr:

class mm(object):
    def __init__(self, **kwargs):
        for varname, value in kwargs.iteritems():
            setattr(self, varname, value)