What Are * and / Parameters in Python Functions? 

What a handy way of reducing the readability of code...

Never knew python has this functionality. Thank you

I like defining the arguments coming in and then passing them in with their name/value pairs so there's no confusion this function takes these things.

sidenote: its usually one or the other not both in one function although you can use both at the same time.

you could have disabled your IDE's parameter hints, because seeing p1=20 being replaced by p1;20 isn't really easy to understand when you don't know what's going on....

I think that in 99 / 100 cases these are a bad thing to use. Any time i make a program or library, i only push it out into the wild once it's a semi-polished diamond. So restricting which method of calling functions people want to do seems only useful for core python libraries or nuclear power plant level type stuff. The / does help at avoiding breaking changes (as noted in the video) but it also forces users to write worse code, which could be affected by people swapping around arguments in the function name. If a function name loses a bunch of parameters, it could still end up breaking a user's program. I still think it's a really good video, since now i know what to do whenever i see this in a codebase and kwargs aren't accepted 😈

the asterisk seems to work somewhat similarly to *args. You can have any amount of *args, so the only way to pass arguments that go after *args and let the function know what they are is to specify them as keywords.

did someone run out of ideas for adding new python features?

Slightly confused by those parameters names followed by a colon. Is that just something your editor shows ?

Thanks for this good video on this esoteric python functionality. It seems python has "jumped the shark" by adding cruft for edge-case use. I prefer to stay away from using these parameters, unless I really, really need them, as it makes the code less readable. Eventually, languages and everything in life adds all these specialty items, like all the kitchen gadgets one can acquire instead of simply having general purpose kitchen tools. Egg timers are great for people who boil eggs all the time, but if you do it once per year, skip it.

2:42 The only good thing is it's great ability to make it so that the company can't hire anyone else as no one else will understand what your wrote, so your aren't replaceable.

Holy... That's just in time... In my code I want to make sure that arguments should be called as keyword arguments for "security" reasons (rejecting wrong interface usage out of pipelines).

For everyone asking when this is actually useful: I use this whenever attempting to mimic other language’s signature overrides. This way you can combine multiple different function signatures under the same name but have separate “pathways”. I.E def foo(x: int , /, y: Any, *, z: str) could let you provide different control flows given a combination of parameters given

Never knew about this , thanks !

What is that prefix-colon thing, like print(p1:10) ? I've never seen it before and it's a syntax error in my CLI.

Adding a new feature to Rust: No that'll add too much bikeshedding Adding a new feature to Python:

apart from restricting usage, is there any other efficiency benefit to using * or /?

Great tutorial, thanks man!

Excellent, as always 👍

In decades of coding I've never seen / or * once used for real the wild*. I wonder if there's anyone that will ever watch this video that has. *not including *args, **kwargs which are everyday ofc

Cool! Does it also exist in python 2.7?

Bro, excellent! I am a subscriber from Uzbekistan. You always teach us the best things about python. Good luck Bro!

Would like a lot a series on Python reflex library

Very useful. Thanks

quick summary: Slash (/): Makes everything before it a forced positional arg Asterisk (*): Makes everything after it a forced kwarg # Ex1 def func(param1, param2, /, param3): # Will make param1 and 2 forced positional pass # Ex2 def func(param1, param2, *, param3): # Will make param3 forced key word arg pass # Ex 3 def func(p1, p2, /, p3, *, p4): # p1 and p2 are forced positional, and p4 is forced kwarg. pass # Came up with this extra example myself when wondering what would happen if they overlap: # Ex 4 def func(p1, *, p2, p3, p4, /, p5): # When combined and conflicting, asterisks are more powerful pass func(1, p2=2, p3=3, p4=4, p5=5) # p1 is forced positional, the rest are forced key word args.

What is this theme? It looks kinda like One Dark Pro but with a few colors changed

I did not know about this!

Thank you

Hey, just had a completely different question, how can I get that keyword showing when calling a function like p1:10 in nvim? I see u use pycharm or something but is it possible on nvim?

what version of python was this introduced?

U r da best

bro you’re the best, thanks

When will you upload flask 3rd Tutorial

This is a wretched syntax

I never knew or remembered this functionality in Python, thus never used it or had the need for it. This is another example of adding junk to a language that has no semantic purpose or need for. I mean all programming languages pass arguments to functions based on the order of the parameters defined in the method signature.... simple as that

None of the putative uses for these things are compelling - just seem like needless complications all round.

This certainly bug inducing behaviour and violates the keep it simple principle. Don't recommend using such corner cases.

this is useful knowledge, but not very useful functionality from python I'd rather python spent effort in being less verbose

I have to say, this has got to be the dumbest anti-feature I have ever seen. The ability to take away disambiguation is never a good idea. It's paired a horrible syntax too: passing math operators as standalone arguments is not a concept anyone can understand without a thorough explanation.

Definitely code smell.

Python. Meh.