[Python] How to deal with multiple parameters (1)

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Normally We’ve done this like…

Probably the majority of experienced python programmers would have encountered this wonderful syntax and have already incorporated this method to their programming skills or style I guess.
It is about how we put multiple arguments when making a function. What if we do not know how many parameters we need for a specific function?
In python, there is wonderful way to deal with this problem which is *args.

Let me take an example.
Normally, we would write a function that adds two parameters as below.

def addTwoParams(a, b):
  return a + b

Now, your boss is telling you to fix the function to one that takes five parameters and sum them all up. What are you going to do?

def addFiveParams(a, b, c, d, e):
  return a + b + c + d + e

If your coding style was as above, this blog post will help you survive from your vicious boss.

*args

def adder(*args):
    return sum(args)

print(adder(1, 2, 3, 4))	# 10

The parameter name “*args” stores unknown number of arguments to the variable named “args” as a tuple data type.

Below is the proof.

def showArgs(*args):
    return args

print(showArgs(1, 2, 3, 4))		#(1, 2, 3, 4)

If you’ve once learned the concept of Functional Programming, you will catch this programming concept quite quickly. This is because the syntax teaches a function How to process rather than imperatively order a function What to do.

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How to deal with multiple parameters (2)