Pythonic function overloading?-CodePudding

Im having trouble understanding clean way to do this. I would like a function named set_delay() that take a variety of parameters. I have 3 different "delay types" that can be set: constant, uniform, and normal. Here is what I currently have:

def set_delay_constant(delay):
    continue

def set_delay_uniform(min_delay, max_delay):
    continue

def set_delay_normal(mean, std_dev, timeout):
    continue

The problem I have with the above is that about ~80% of the code in each function is repeated. Ideas Ive seen are:

def set_delay(delay_type, delay=None, min_delay=None, max_delay=None, mean=None, std_dev=None, timeout=None):
    continue

But when I need to extend this with more delay types, I can see this getting very long and hard to read. What is the most "pythonic" way to go about this? Thank you!

CodePudding user response：

Don't use overloading. Where the problem that you're trying to solve is "about ~80% of the code in each function is repeated", the better solution is to factor out that code into its own function, call it _set_delay for example, then call it from each of the set_delay_* functions.

To me, overloading only makes sense where the parameters overlap, but none do in your case. For contrast, say I write range(10) but then I realize I want to start from 1; thanks to overloading, I can simply change it to range(1, 10). Meanwhile, if I added an argument to your proposed set_delay, I would get totally different behaviour.

CodePudding user response：

I would personally move to a class based structure:

from abc import ABC, abstractmethod

class Delay(ABC):
    def do_delay(self):
        self._prepare_delay()
        #put the 80% of overlapping code here

    @abstractmethod
    def _prepare_delay(self):
        pass


class ConstantDelay(Delay):
    def __init__(self, delay):
        self.delay = delay
        #custom code can go here

    def _prepare_delay(self)
        #more custom code here

class UniformDelay(Delay):
    def __init__(self, min_delay, max_delay):
        self.min_delay = min_delay
        self.max_delay = max_delay
        #custom code goes here

    def _prepare_delay(self)
        #more custom code here

#etc

Then your set_delay function would take a single argument, an instance of a Delay subclass:

def set_delay(delay):
    pass