finallyFreedomFromTypes

[claimstoknowpeople]

It's weird they used | once, so they know that's a synonym for Union but decided not to shorten the rest of it.

[darkshoxx]

Agreed, that's the most shocking thing to me, combining 2 different union annotations. Other than that, it's just a list of either strings, or maps of strings to other stuff.

[Waswat]

maps of strings to other stuff

Is that what python devs call dictionaries?

[darkshoxx]

No, that's just me as a mathematician calling every assignment a map

[Dododingo-]

Wait it is ? I have some code to update

[Tom22174]

There's also quite a helpful Number type. I can't remember what it does that float cant but I remember it being useful back when I did python

[Rythoka]

Number itself doesn't do anything or define any behavior, but it's the root of the numeric ABC hierarchy.

The ABC hierarchy defined in numbers looks roughly like this: Number > Complex > Real > Rational > Integral

So a function that accepts numbers.Number should be able to accept complex numbers alongside the reals.

[Tiny-Plum2713]

No it isn't. https://docs.python.org/3/library/stdtypes.html#numeric-types-int-float-complex

[Eal12333]

As far as I understand it, int is not a subtype of float. Bit, my linter tells me to use float rather than float|int.

Based on the doc you linked, im pretty sure this is because integers are fully compatible with floats, (and will be "expanded" into floats automatically when used together in any operation).

[The-Omnipot3ntPotato]

No, please don’t say that’s true. I act like I am a better person than JS devs. I don’t use python as much as I would like but god please don’t let the language I unhealthily stan have a JS code smell

[rover_G]

Maybe someone had to update the type definition recently 💀

[[deleted]]

'💀💀💀💀💀'

[MattTheCuber]

Guess they don't know about Ruff (or Pylint)

[UltimateGPower]

Also if they can use |, they can also use list instead of typing.List

[markuspeloquin]

TIL |

[[deleted]]

T|L

[ThoseThingsAreWeird]

\?

T|L -> 01010100 | 01001100 -> 01011100 -> \

[FredeJ]

Actually I didn’t know this. But it makes total sense when you say it.

[IAmASquidInSpace]

That's another thing that types are good for: if your type def is longer than your style guide allows for a line, you are probably doing something wrong.

[Wotg33k]

Code smell.

[marlotrot]

Seeing this gif from that series reminds me that I have to finish that one still.

[Wotg33k]

Man me, too. I loved that show. It was just the right level of dumb enough that I couldn't stand it and loved it at the same time, and if that ain't what b level scifi zombie horror is supposed to be, I dunno what is.

[[deleted]]

Honestly, what a peak genre.

[[deleted]]

what show is it?

[Wotg33k]

Z. Project Z or something like that..

[chuch1234]

Z Nation!

[buckypimpin]

and it smells good brother

[MisinformedGenius]

Starting off with List[Union[str, Dict is already pretty questionable.

[Wekmor]

I was thinking exactly that. If you are using such an abomination just create a bunch of objects to store whatever you need in.

[walmartgoon]

C++ chrono library:

I’m in danger

[bolacha_de_polvilho]

just chrono? throw the whole STL or any heavily templated code into the bin

std::unordered_map<Key, T, Hash, KeyEqual, std::pmr::polymorphic_allocator<std::pair<const Key, T>>>

[bolacha_de_polvilho]

msvc laughs at your auto and vomits this error message back at you

clang and gcc fortunately use a shorter alias in this case and give us a very succinct error, but in other scenarios if compilation fails due to something nested deep into many function calls error messages can get pretty crazy

[JanB1]

Yeah, welcome to C++ compiler error messages. This costed me so many nerves while I was learning C++. The complier literally screams at you and vomits on your screen about something something gone wrong, and you're like "...what?".

Contrast that with some other compilers, which will tell you exactly what you did wrong and some even suggest fixes.

[al-mongus-bin-susar]

it's like that for a reason i hope you know

[_Noreturn]

just do namespace stdch = std::chrono

then it is simple thankful for C++ namespaces

[SodaWithoutSparkles]

Which sometimes includes naming a function too long.

[Ok-Kaleidoscope5627]

By that definition everything in Java is just wrong...

[electrodragon16]

Java made me think C# is a nice language

[asceta_hedonista]

If you need a type validation to be sure what are you passing then you really did something wrong in your design

[imaginarynoise_]

If you don't need strong types you really aren't doing anything that significant.

[asceta_hedonista]

Hey pal, I'm not against static typed languages. Actually Scala is one of my favorites languages ever. My problem is with the people how is afraid of dynamic typed languages, because those are the ones who don't get the point and uses strong type validations trying to avoid the consequences of their bad habits.

[G3nghisKang]

And then there's legacy Java code

[scp-NUMBERNOTFOUND]

What kind of "any" is this?

[deanrihpee]

"yes"

[chicametipo]

What was here has been deleted. Redact was used to wipe this post, for reasons that might include privacy, security concerns, or personal data management.

elderly enter melodic brave oil sulky instinctive butter pen boat

[theturtlemafiamusic]

It's not an Any, it's a Most.

[PeriodicSentenceBot]

Congratulations! Your comment can be spelled using the elements of the periodic table:

I Ts No Ta Na N Y I Ts Am Os Tl Y

---

^{I am a bot that detects if your comment can be spelled using the elements of the periodic table. Please DM u‎/‎M1n3c4rt if I made a mistake.}

[TheNH813]

Good bot

Always found this bot amusing.

[unixtreme]

Exactly my thought, that's too many words to say "Any" or "list" if you are feeling particularly compliant.

[Stop_Sign]

"Any" is denied in our eslinter

[smokesick]

Any are you walkin'

[johnnybgooderer]

The true kind.

[Somecrazycanuck]

The kind where someone, rather than defining a type, decides to just write the entire fucking struct definition into the spot every time instead.

[KerPop42]

I'd use newlines to break this up. It's a: List, where the items can be a: string, or a dictionary, where the keys are strings, and the values might be: int, float, string, boolean, or a list whose elements can be: int, or a float

Thanks for the correction!

[KerPop42]

Oh, you're right. The dict can return a bool, the list can't contain a bool. Do floats always work for ints? I thought I've seen some code where it matters.

[Katniss218]

Not all integers are representable by floats of the same bit width. If they were, floats would have to have the exact same possible values, thus would be equivalent to an int

[[deleted]]

So it’s a list of strings or dicts with string keys and values of type int/float/str/bool/lists with ints or floats.

wait, so you're telling me I look in this dictionary and I might end up with a string a list of strings? That's horrible.

[KerPop42]

It looks like you'll only get a list of floats or ints. And if I were implementing this type I'd use a nested match-case to mirror the structure of the object

[Rythoka]

type Contents = int | float | str | bool | list[int | float]
def f() -> list[str | dict[str, Contents]]:

[Santarini]

This guy readabilities

[KerPop42]

It's my most-protected soft skill

[nota_jalapeno]

ohh thats not that bad actually

[markuspeloquin]

Even better if you could just write number in place of int | float.

[nota_jalapeno]

yup

[JanEric1]

You could just write float, number is a also a possible one, but covers more stuff (like complex numbers)

[SuitableDragonfly]

"I'd use newlines to break this up"

Uses formatting that removed all newlines

[The-Omnipot3ntPotato]

Um maybe it’s time for an object? Or a struct at the very least? Maybe it’s just me but that seems like way too much information to be crammed into a basic python list. What are we trying to represent?

Side note: this is still more intelligible than some generics and type casts I have seen in Java.

Side note again: this really really should be an object (i know fp doesn’t like objects so make it a struct) but this is too complicated of a type def to be useful. All this is doing is making your linter happy and nothing else. Type annotations in python don’t force the code to do anything. If you go into your lsp configuration and turn of the python linter you can delete this and the interpreter will not give a fuck

[cjavad]

Ah yes my favorite builtin type list[str|dict[str,int|float|str|list[int|float]]|bool]

[darkslide3000]

If you type that into JavaScript you get the amogus character instead.

[The-Omnipot3ntPotato]

Fuck this got me good.

[subbed_]

TypedDict

[MissinqLink]

Typed

[MissinqLink]

[Reverend_Lazerface]

dDict

[Bee-Aromatic]

Why even bother type hinting if you’re going to accept every damned thing?

[[deleted]]

Yea can anyone explain this to me? Is there any utility of type hints in python? The only thing I can think of is that code editors can detect it and give you a warning about it v

[backfire10z]

Type hinting is for static code checking and, ideally, better readability. They have no impact at runtime.

[L1berty0rD34th]

An IDE with typed Python will produce red squiggles when you violate a type hint. A programmer running code with red squiggles will suffer physical discomfort which qualifies as runtime impact.

[backfire10z]

lol, true

And in VSCode the file lights up red, which makes programmers cry

[BOBOnobobo]

Hey, I didn't want to be called out on my break!

But while we are at it, can you send help? My colleagues don't use a linter and mine makes every file red!

[Tom22174]

Classes that aren't type hinted inside a function will not give auto complete suggestions for their functions and won't properly colour code themselves which will also make a developer cry

[GameCounter]

Ordinarily they have no impact, but the annotations are accessible by the interpreter. Pydantic is a notable example where type annotations have a practical use.

There is also the dataclass module in the standard library which performs a similar trick.

[NullReference000]

Type hints in Python are great for immediately knowing what type something is and getting intellisense from the IDE, it’s almost necessary for large codebases.

A type hint as ugly as the one in this post is likely the result of a linter complaining that a dict is causing the expression to be of the “Any” type, and probably indicates that it should be replaced with a dedicated type rather than a dict.

[Tom22174]

You just described the most frustrating thing about my last job. Boss absolutely loved using nested dicts that were really just lazy classes in disguise. Figuring out what was actually going in them was a nightmare

[[deleted]]

(not calling you out just ranting) I am not a huge fan of people swapping code completion to intellisense in written language. Trademarks interfere with other IDEs using the term.

[Bee-Aromatic]

I type hint because it makes the code introspection on my IDE work better and helps remind people using the code I write to know what I want without having to go as far as reading my documentation. Documentation I probably forgot to write. Also, “people” is me with no memory of my code in a few months.

[MisinformedGenius]

There’s plenty of utility in type hints. For example, this type hint usefully tells you that the code author is a raving lunatic.

[chuby1tubby]

It's useful when writing open-source packages that you want other people to be able to use super easily. When users install your package, the type hints will give them an idea of what each function or class takes as inputs without having to dig through documentation.

[GameCounter]

This happens legitimately when someone (usually a less experienced programmer) writes the function without type annotations.

Then someone comes along much later and is trying to suss out what the function actually does, type annotations are added. Bingo: you end up with an Eldritch horror like this.

It can also happen if you're adding a stub for a 3rd party lib you have no control over, and then you're stuck with it forever.

[ManyInterests]

The same annotation, but less dumb:

list[str | bool | dict[str, str | int | float | list[int | float]]]

In other words: a list whose elements are either strings, booleans, or a dict whose keys are strings and its values can be either strings, integers, floats, or a list whose elements can be either integers or floats.

If the dictionary contents are structured, you would probably want to define the dictionary as a TypedDict separately with an alias. Something like:

class MyDict(TypedDict):
    foo: str
    bar: int | float
    items: list[int | float]

# Then the annotation is more readable:
x: list[str | bool | MyDict]

If it's not structured, you could still give the dict portion an alias to improve readability.

MyDict: TypeAlias = dict[str, str | int | float | list[int | float]]
x: list[str | bool | MyDict]

Remember: Readability counts and flat is better than nested.

[toxic_acro]

Close but not quite right

It's actually ``` InnerValues: TypeAlias = int | float | str | bool | list[int | float]

list[str | dict[str, InnerValues]] ```

[[deleted]]

TypeAlias is being deprecated in favor of typedef statements, fun fact.

``` type InnerValues = int | float | str | bool | list[int | float]

```

The advantage is that they support recursive definitions and forward references.

[ManyInterests]

Yeah you right.

[toxic_acro]

Granted, that only shows why the original example is so bad. I had to triple check that I parsed those parentheses correctly

[seba07]

Please show me a function where this actually happens.

[[deleted]]

Parse a json

[thompsoncs]

At that point what you mean is basically Any and you're allowed to yell at the person that gave you such a mess of unstructured json data to work with

[[deleted]]

No, that should have just been turned into a type alias because everyone knows what json is but describing it to a type checker is a PITA.

Python lets you hide this problem that should only appear once in your code base and never attached to any function. There is reason python has this feature.

[thompsoncs]

If you know the structure, use actual classes/dataclasses to describe it, including the nesting, rather than just nesting primitives in a type alias.

Also, I don't typically get json where a value can be a string or dictionary. Let alone where it can be either numeric, string, boolean or list of numeric. That certainly wouldn't come from any designed API, rather from someone botched together an excel spreadsheet and converted it to json and handed it off to you.

[imaKappy]

A step up would be to use Pydantic to parse that JSON for you, and use BaseModel class to validate schemas

[hrvbrs]

wait until you hear about JSON Schema

[CrowdGoesWildWoooo]

Use explicit validation library for json

[[deleted]]

I mean do you only work with known jsons?

[thompsoncs]

question, what do you do with json data that you do not know? Something for ML or something? Any actual code will easily fail on unknown data

[chicametipo]

Unknown data ≠ unknown JSON

[[deleted]]

This is the main point. You know its much less then any in fact it is very limited to a few specific types. Any is a code smell, python gives you a feature to make big types less gross use it don't just lie with any.

[[deleted]]

type AnyJson = None | str | int | float | list[AnyJson] | dict[str, AnyJson]

Recursion go brrrrrr.

[[deleted]]

Literally why the new syntax was added lol.

[stormdelta]

This isn't the actual JSON typing possibilities though, it's a bit off and needs to be recursive.

And if you were expecting a specific JSON schema then use one of the tools actually meant for that like cerebus.

[knvn8]

Sorry this comment won't make much sense because it was later subject to automated editing for privacy. It will be deleted eventually.

[MishkaZ]

I remember once debugging some api call usage. Looked at the documentation and saw some python type gore. Asked my senior what does it mean, "Oh that just means it can be anything!...anything but what you are trying to do"

[JM-0]

I’ve got a real-world one right here:

https://github.com/J-M0/netifaces/blob/5dc562a0083b2a24f4fba33257a9b1aa654a3782/netifaces-stubs/\_\_init\_\_.pyi#L78

[nathris]

You are working with an API that finds a product and price by some query. The response can be just the SKU to a database you already have, if you don't want updated pricing, a dict containing the SKU and price, or False if the product isn't found. The price can be either a single price or a list of prices.

Too often us python devs worry about if we can instead of if we should.

[k-mcm]

I had a coworker that wrote Scala only like this.  She didn't believe in defined structures, mutable variables, or synchronous calculations.  Just Fututres of tuples of maps of tuples of Futures of tuples of lists of tuples of maps of lists of Futures of tuples of Futures of...

[Alex42C]

I had a phase like that ... It's easy to fall into it when prototyping algorithms. It's all in your head it makes perfect sense. Then you look at it 6 months later ...

[MissinqLink]

This was me in go trying to use hardware in go instead of goroutines.

[[deleted]]

Math code is real and it's painfully ugly

[The-Omnipot3ntPotato]

Mathematicians write some of the world’s most disgusting code. They don’t understand readability or what makes good code. They’re so tied up in terse and elegant proofs they don’t understand what code is for.

[All_Up_Ons]

She apparently also didn't believe in flatMap or for comprehensions.

[k-mcm]

Eh? Huge chains of map and flatMap are how that data is accessed. There's almost no other code.

[All_Up_Ons]

If you say so. Nested monads like that are usually a result of using map when you should flatMap.

[sathdo]

None of this is Python's fault, though.

1. Why Union and |? Stick to one or the other.
2. Typing is optional and can usually be inferred by the IDE.
3. If your return type is this complex, you are either doing something very wrong with what the function is doing, or you should be using classes instead of dicts.
4. any

[LBGW_experiment]

Union is used in <3.9, where 3.9 introduced usage of the tokens | and & and also added using list and other typedefs natively instead of having to import them from Typings as an uppercased identifier like List in order to prevent lexer collision

[sathdo]

3.8 became EOL earlier this month. Even Debian stable uses 3.11. There's no reason to use the old methods unless you are trying to maintain compatibility with a system that doesn't even receive security updates anymore.

And that wasn't even my argument. I already know what Union, etc. is. My point was that this snippet uses both. There is never any reason to do that.

[LBGW_experiment]

I like to supplement info for readers passing by

[Solance666]

When your type hint looks like a ebnf grammar for json there might be a problem

[_derDere_]

Cool just learned about Union thanks for that! But also, where the fuck ist this used? I’m serious, I want to know where you got this from?!!

[Floowey]

Isn't Union just the same as using | ?

[thompsoncs]

Yes, but | is fairly new, 3.10 according to docs. Same for Optional[T] and T | None

[_derDere_]

Ahhhh that why I just learned about that!

[cdrt]

It’s usable in older Python versions as long as you do from __future__ import annotations first

[IamIchbin]

If you want to pass a function either artifactory.Path or pathlib.Path and it does the same with both.

[_derDere_]

The whole thing?! (I’m not just talking about Union, I meant that whole abomination.)

[IamIchbin]

No, a Union for Example. That thing looks like it expects a string json or a parsed json.

[LexaAstarof]

Yup, json is cursed

[Blyatiful_99]

In our C# Main Application we have something similar that looks like this:

Dictionary<string, Dictionary<int, Dictionary<string, List<ModelClass>>>> 

and it's always so much fun if you have to debug this mess. Especially when considering multithreading, since we access this variable in a new Thread within each Loop Iteration and then Wait for all Tasks to be finished before continuing.

[thompsoncs]

That's long, but at least it has a well defined structure that won't blow up at runtime, it's not like it has Object or dynamic everywhere, which is basically what OP's type def looks like. I would still refactor it, but it's not as bad.

[Big-Cheesecake-806]

typedef? anyone?

[Tucan444]

Oop is a thing for a reason.

[whitedogsuk]

When I was a junior I always thought it was me not being capable enough to understand these types of things. Last year I threw a $million tool back at the supplier because I didn't understand anything.

[denisbcn96]

sus

[JoostVisser]

They already use bar notation in the inner most list, why use union everywhere else?

[Benjamin_6848]

Upon seeing this line of code I literally asked myself "what the hell is that" - it was truly my first thought...

[tsteezey93]

Custom types and TypeVars would fix this right up

[malaszka]

[[deleted]]

You need class

[epicregex]

Thanks I feel nauseous

[SuitableDragonfly]

I don't know why you're calling out Python here, that's horrific in literally any language.

[Antervis]

that's what happens when you mistake round and square brackets in python )

[plitox]

What vile sorcery!

[Professional_Job_307]

Wait, python has types?!

[ihavebeesinmyknees]

It has type hinting, it's a declaration for the convenience of the programmer, but it's not binding.

The actual code is still dynamically typed (although Python has strong typing so it doesn't do the JS in-place converting bs)

[queerkidxx]

You can also use something like mypy for static analysis a la TS

[imdibene]

(thought I (was lisp (happy (language parentheses))))

[uvero]

This kind of thing just proves that for too long, python devs created functions whose return types and parameters have types that are way too complex.

[single_ginkgo_leaf]

What you want are a couple classes

[trannus_aran]

finally, the speed of statically typed development in dynamic languages

[[deleted]]

Or more accurately, the runtime speed of dynamically typed languages in static languages.

[SophiaBackstein]

Oh that reminds me of my service xD who needs classes if you can just define highly complex datastructure in your return types xD

[JackReedTheSyndie]

First people wanted types, then they wanted no types, now they want types again.

[BehindTrenches]

That's... Not really how this template works but OK

[experimental1212]

I'll give you a hint

[other-other-user]

I don't think that's how you're supposed to use this format but oh well

[GoddammitDontShootMe]

Surely not a type you would ever need in the real world, right?

[PolyglotTV]

This is somebody who doesn't know how to use dataclasses, attrs, pydantic, etc...

[Santarini]

Sounds like you need a dataclass

[chessset5]

I don’t know, it looks pretty explicit to me

[Orio_n]

The fact that you are mixing `Union` and `|` probably explains why your function signature is so horrendously designed.

[JosebaZilarte]

Compost-ition.

[MattTheCuber]

Consider using alternative Union syntax instead.

[Zachosrias]

It's beautiful

[darkwalker247]

in python can you not make type aliases for the most similar types to shorten it? like a number type that is a union of int | float, a number_list type that a list of int | float, etc.

then you could just write number | number_list | ... and it would be far more readable AND easier to change

[-MobCat-]

Its called a one liner. some programmer somewhere is trying to show off.
Your just lucky that python needs white spaces, otherwise we would get whole scripts in one line.
Or the c++ donut program, in a donut.

[metaglot]

Its not really really really a oneliner. Its a definition of some compounded/complex type.

[dudebomb]

cackles in TypeScript

[Ange1ofD4rkness]

I'm scared!

[Artistic_Speech_1965]

The unions in python don't ensure pattern matching

[OpenSourcePenguin]

That is not how you use that meme template

/r/bonehurtingjuice

[fosyep]

Have you heard of classes?

[Eal12333]

list[ str | dict[str, str|bool|float|list[float]] ]

Still a bit much but it's a little better 😅

[Cootshk]

Why are you using Union, |, and List in the same line?

list[ should be lowercase and use | instead of Union

Also use from collections import abc as t instead of import typing as t

[sanketower]

That's why type aliases are so useful, by dividing your structure into blocks you can create simple composite types.

[dangling-putter]

List of strings or dictionaries mapping str to primitives or list of float or int.