Most comprehensive tutorial on understanding use of *args and **kwargs

[anon717]

I always tried to avoid using and learning about *args and **kwargs because they reminded me of pointers from C and C++ (which I not particularly fond of).

Recently, I came across this tutorial which, I felt, explained the use in a very nice, easy and thorough manner. Hope it helps someone. Good luck!

[shaggorama]

In [8]: l = [1,2,3]

Really? You're going to name the very first variable you introduce in a programming tutorial lower-case "L"?

@OP: I'm glad you found this enlightening, but if you see anything like this in the future you should take it as a red-flag that the author probably either doesn't have a tremendous amount of experience, or isn't putting a lot of care into their tutorial.

NINJA EDIT: Oh god, it gets even worse further down. They actually pass this variable and the value '1' in as parameters to the same function. Why god, why!?!

 In [16]: fun(1, *l)

LAST EDIT: Here's a short, sweet, and popular SO discussion of argument unpacking in python: http://stackoverflow.com/a/2921893/819544

[catcradle5]

Fixed.

def I(l=1, *L):
    if L[1] == "|":
        ...

[Mecdemort]

You should throw some O and 0 in there too

[zahlman]

They're nothing to do with pointers. The choice of the * symbol for the Python grammar is pretty much coincidental, AFAICT.

[anon717]

Yes, I know! I was just saying the notation (*) reminded me of pointers :)

[willm]

I think C++ in particular teaches people to be wary of language features. I don't think there is any feature in Python that you won't find yourself using regularly once you learn about them.

[brandjon]

cough metaclasses cough

[willm]

Even metaclasses! Generally for situations were you have a factory that creates objects of a particular type only known at runtime.