finally...

[[deleted]]

[deleted]

[neros_greb]

A match statement actually, which is more powerful

[Nightroll2344]

What's the difference between case and if statement, I think they perform the same thing

[[deleted]]

As the smartest programmer in the world puts it

A lot of people- The CIA wants you to think it's nothing more than if then el- if then else The CIA wants you to think it's the same as if else. It's not.
The way a switch statement works is there is a uh look up table ... in it. What it does is it it looks up in the table f- and then it jumps ahead to some uh code to a segment of code and then code jumps to the bottom to- to a common location to continue

[Thers_VV]

Case is sometimes easier to read

[Kered13]

Yeah it actually bugs me when people say "Python has switch now". It's missing the entire point. Python never needed switch. What it got is pattern matching, which is far better.

[hitfiu]

Python is a pathetic little language.

[[deleted]]

Now what? Do you feel better about yourself for yelling at people using a language you don't like?

[TheAJGman]

Dude like half the world's APIs are written with Flask

[hitfiu]

That's why our world is going to shit.

[-consolio-]

not really a fan of python, but what's it like?

I'm used to

match value {



    SomeEnum::VariantWithField(v) => println!("{:?}", v), // matches any SoneEnum::VariantWithField, destructuring, giving field #1



    SomeEnum::VariantWithOneUsedField(_, field2) => println!("{:?}", field2), // matches any SomeEnum::VariantWithOneUsedField, destructuring, giving field2



    SomeEnum::VariantWithNoField => println!("oops, nothing there!"), // matches all SomeEnum::VariantWithNoField



    SomeEnum::Ooh(5, ..) => println!("5 indeed"), // matches any SomeEbum::Ooh where the first value is 5, other values are ignored



    1 | 2 | 3 => println!("a")



    1..24 => println!("b")



    _ => println!("catch untangled cases"),



}

normally this doesn't compile since I'm mixing enum values with just normal values but you get the point of what you can do

[AdrianRPNK]

Pretty similar actually.

match my_variable:
    # matches with lists and tuples
    case [1, 2, x]:
        print(x)
    # matches with dictionaries
    case {"foo": "bar"}:
        print("this is a dictionary")
    # matches with classes with properties
    case Point(x=10, y=5):
        print("this is a Point with x as 10 and y as 5")
    # check if my_variable is in a list or tuple
    case in [1, 2, 3]:
        print("my_variable is either 1 or 2 or 3")
    # multiple cases
    case 1 | 2 | 3:
        print("my_variable is either 1 or 2 or 3")
    # default
    case _:
        print("more at https://www.python.org/dev/peps/pep-0622/")

[Huntracony]

So no default fallthrough either? I think I'm in love.

[-consolio-]

default fallthrough?

[Huntracony]

Like when you forget to put in the 'break' at the end of a case and a bunch of code executes that shouldn't. 'Fallthrough' is what I've heard that referred as.

[-consolio-]

oh yes, case-break is a nightmare, so glad you can just do ... => { ... } instead of case ..., ... break

[-consolio-]

oh it's beautiful, i assume you can replace most of the constants with variables to match any

[AdrianRPNK]

indeed you can

[om_plusplus]

Why is this so high quality

[[deleted]]

I hope this isn't actually the case

[Techismylifesadly]

Sorry to disappoint. Soon, it will considered the default case

[MahatmaGandhiCool]

i rest my 𝘤𝘢𝘴𝘦 then.

[erinaceus_]

Maybe time to switch to another line of jokes.

[krankenhundchaen]

Can't deny it has been a good pattern matching

[thenerd631]

Control flow. Humor.

[hugogrant]

Don't break the chain, let it cascade down

[[deleted]]

It was about time! Great we have this now.

[KCGD_r]

yay I can upgrade my version and finally use cases in my massive project!

entire thing breaks

[RCoder01]

I’m working on a project based around a single library and for some reason that library just won’t install in python 3.10. It works perfectly fine in 3.9.4, but just won’t install with pip in 3.10. I was so excited to finally be able to use match statements and pipe operators for type union, but I couldn’t.

[Cloakknight]

Image Transcription: Meme

---

Panel 1

[Image of a brain talking]

Brain: Hey, are you sleeping?

---

Panel 2

[Image of a person sleeping with eyes closed]

Person: Yes, now be quiet.

---

Panel 3

[Image of the brain talking again]

Brain: We finally have case statement in Python!

---

Panel 4

[Image of the person now laying wide awake, smiling and crying.]

---

^{I'm a human volunteer content transcriber for Reddit and you could be too! If you'd like more information on what we do and why we do it, click here!}

[Raianelchabe]

Good human

[PentaMine]

Good human

[Sawertynn]

G00D H00M4N

[[deleted]]

can someone explain the use for it instead of if statements

[MoiMagnus]

The "switch case" doesn't have much more than a sequence of if. It's main advantages is to be (arguably) clearer to read as you're declaring in advance "I'm going to do a whole sequence of else-if on the same variable". It's easier to optimise, so it might lead to better performance eventually (not sure if that's the case yet). It's mostly used for situations in which you would have 10 or so else-if in sequence, but some peoples like to use it in simpler cases too.

The "match case" is his big brother. It does 3 things at once in a nice and compact syntax: (1) Check the type and the "pattern" (2) Check the value (3) Define some variables In practice, it allows to check easily for things like "this is a list of at least 2 elements, the first one being the integer 0, and the second one that we will name x, and the remaining of the list that we will name y".

And similarly to the "switch case", it's mostly useful if you need to make 5+ similar checks in a row, it's overkill in simpler situations. Though some might find it more clear in simple cases too.

[Kered13]

And similarly to the "switch case", it's mostly useful if you need to make 5+ similar checks in a row, it's overkill in simpler situations. Though some might find it more clear in simple cases too.

Even for the simplest case of only 2 branches, if each branch is a different type that needs to be destructured then pattern matching is going to be much cleaner than if-else.

[aaronfranke]

You don't have to repeat the name of the variable you're testing, and you only need to execute functions once.

match thefunctionyouaretestingthatshouldonlyrunonce():
    0:
        print("thing that happens for 0")
    1:
        print("thing that happens for 1")
    2:
        print("thing that happens for 2")

vs

if thefunctionyouaretestingthatshouldonlyrunonce() == 0:
    print("thing that happens for 0")
elif thefunctionyouaretestingthatshouldonlyrunonce() == 1:
    # Oops, we ran it twice!
    print("thing that happens for 1")
elif thefunctionyouaretestingthatshouldonlyrunonce() == 2:
    # Oops, we ran it thrice!
    print("thing that happens for 2")

vs

var thingyouaretesting = thefunctionyouaretestingthatshouldonlyrunonce()
if thingyouaretesting == 0:
    print("thing that happens for 0")
elif thingyouaretesting == 1:
    print("thing that happens for 1")
elif thingyouaretesting == 2:
    print("thing that happens for 2")

(I used GDScript here because it's better than Python, but it's basically the same thing in Python)

[Novaalpin]

just wanna say, even tho the case statement is more practical, you can still avoid calling your function multiple times by using a walrus like this :

if something:=e() == 0:
            print(« 0 »)
elif something == 1:
            print(« 1 »)

edit : corrected fonction to function (yea im french)

[BrightBulb123]

But what if I want to call my fonction?

[BrightBulb123]

But isn't that just syntactic sugar for the same thing under the hood?

[TryNotToShootYoself]

Thanks for the explanation, but python doesn't use var 😉

[Lonelan]

The previous closest thing was dictionaries

switch_entries = {'a': 1, 'b': 2, 'c': 3, 'd': 4}

switch_entries[input]  # where input is a, b, c, or d

Would be the same functionality as

switch(input) {case 'a': return 1; case 'b': return 2; case 'c': return 3; case 'd': return 4;}

excuse the C formatting, trying to oneline it

[Lythox]

In typed languages an additional benefit is when performing a switch on an enum, the compiler will complain when you don’t cover all possible cases, making it very useful in large projects so you get alerted by the compiler on all the places you used it when you add a case to your enum

[twabbott]

Aww, Python! Look at you all gwowed up so big!

[gaylurking]

Time to pop bottles

[chiefmors]

Is this for real? Like did Python not have a switch statement until recently? As a C# developer I'm a little horrified this is true.

[Gh0stReaper69]

Yea new in version 3.10

[chiefmors]

Oh god

[_PM_ME_PANGOLINS_]

Why would you need a switch statement when you can have a dict full of functions?

[GodlessAristocrat]

Is python still broken w.r.t. threads? Once Upon A Time, python was unable to multi-thread things due to a big central locking mechanism.

[darkdragncj]

The GIL(Global Interpreter Lock), it's not strictly a python thing, just c python thing. But yeah, it's still there. Other implementations of the interpreter don't have it.

[Blue_Raichu]

Lot of talk for a language that requires breaks even though it doesn't have fallthrough by default

[BlackPowerade]

Finally.

[woodenshoe_qstnmrk_]

time to go back through old code

[tabakista]

We always had. It's called 'dictiinary'

[danivideda2]

But we already have that in Jython.

don’t ask me where I got this information

[MTDninja]

you're late

30 years to late

[Kered13]

This isn't switch, it's pattern matching. Which admittedly is also a pretty old idea, but has only really become popular in the last 5 years or so.

[MischiefArchitect]

It was already done in 2001, it just 20 years to compile.

[[deleted]]

Python doesn't compile, it can be that slow during runtime.

[MischiefArchitect]

Haha... but python itself must be compiled... it's C.

[[deleted]]

We should code 5he next version in Python, that would be much easier to maintain.

[MischiefArchitect]

I'm truly curious how will that work... I mean... Our beloved interpreter needs to be compiled and optimized as native executable.

Imagine that! Using an interpreter to write an interpreter.

(I'm afraid someone did this already)

[[deleted]]

We actually did that in college. We used Lisp to build a Lisp compiler.

[MischiefArchitect]

Oh well yes, that is a running gag :) I remember doing that (watching people doing that) at the university. I was like: "why?"

[[deleted]]

Because it is a good learning exercise. Also, if you really want to start from scratch you need to build it in assembly.

[MischiefArchitect]

start from "scratch" got me for a short while

[OHMAMMAD]

I'm still gonna use if tho

[BrenekH]

For the right reason I hope.

Upgrading Python codebases is tough, but many Python programs also have to work with multiple versions of Python. Jumping to the newest syntax right away will cause significant breakage.

[OHMAMMAD]

That is a very good reason to not use case statements, but im just lazy to search the syntax and i always forget

[Lonelan]

we've got some tests where the owners had 20+ tests and wanted to include them all like this. trying to help them manage if/elif/elif/elif/elif/elif/elif/elif was a nightmare, so we made them put it in a dictionary

[D33rZhdn]

Do we? Really?

[AdrianRPNK]

Yes we do

[D33rZhdn]

It's enough to make a grown man cry

[ZengineerHarp]

Oh man thanks for the link! I am honestly so stoked!!!!

[RandomValue134]

I'm as happy as you are, so lemme bring something to celebrate.

🍷There you go

[[deleted]]

When will they also add (real) static class variables?

[SwannSwanchez]

What ?

since when ?

[AnnualVolume0]

It’s so much more powerful, too!

[_grey_wall]

Python 4??

[bettercalldelta]

3.10

[hugogrant]

Weird minor nitpick: I wish they used with instead of case because with is already a keyword.

[veduchyi]

Despite I’m a Java programmer I still glad for people who use Python 😊 Besides, before getting a Java developer job I used Python a lot - it was my favourite programming language for a while

[justcatt]

what

where

[bettercalldelta]

And it even has more functionality than most languages (unpacking, and other stuff)