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I just shifted from Django to FastAPI, and the unavailability of an ORM was a shock, and then I came across SQLAlchemy, which came as another shock!

What do you think about SQLModel? Its from the FastAPI creators and combines pydantic and SQLAlchemy, as i noticed you don't need to create extra classes for sql and pydantic

in the bubble sort, the inner loop starts from the outer loop starts which means that there are a subset of elements in the beginning that are not sorted.

Hey 👋 I host a project on my own server (under my couch) with Proxmox, running docker behind Opensense and Crowsec firewall, 1GB speed. I use Cloudflare for the DNS and IP proxy. It's possible, but you have to deal with attackers and hackers. So I Splitt up my Homelan into multiple VLan to exclude privat stuff from the container.

Thank you Arjan for the videos you upload, they're very helpful and have a great quality, both in teaching and technical quality, I have learned a lot from you.

thanks for this video man. i'm learning rust while writing pet project and result really bothered me until i found this video.

I find elimination of state to be mostly an obstacle in concurrent programming because atomic operations make threads inherently agnostic of what's going on and whether they should do a/b/c depending on updated conditions, and it also makes it difficult for them to broadcast their own state as it will require an intermediate who would ultimately end up doing exactly what that thread could be doing autonomously (and with less context). It's not impossible to safely allot partitions of a shared workload or state object by using range/slice-types for instance while retaining communicability.

I'm not conviced by the tuple notation when adding a union of type bounds to a generic. Why a different syntax when you already have unions? It feels like types in Python are still an afterthought. I am also surprised by the comments which are against typing altogether. I hope the most important community packages support types

How do i deal with real world implememtation in which i need a way to deal with the dependencies (external libs) that just my plugin will need to run ? Also, plugins will not be in the same path as of my application, specially when I install it as a onefile (using pyinstalller)..so how to deal with the imports? Please could you make a tutorial with a more "real example"?

Dude! This is crazy i wish i could share u our git repo, i watch all ur vids but havent seen this one! Decimal being slow and incorrect is halarious, we in our use case had to use fractional cents because of LLM cost per 1000 tokens was like 0.00025, we um settled on closest like 50 (rounded) was good enough, but i might make a PR to raise it to the token, just by going from 1e6, to 1e8 I guess it makes sense my code emulates urs as i watch a bit, still eerie tho

I hate trendy paradigms. I find that’s writing better code is just simply about building an intuition for what is right to do. There is no silver bullet.

"Im looking at you pyqt !", love your joke. Thank you for this amazing channel

Arjan, you are soo good at what you‘re doing. Your voice is calm and relaxed. And you are able to transport your knowledge to your audience in the same manner, calm and relaxed. Learning new stuff suddenly becomes like a therapy. No more stress, no more struggle. Thank you very much. Please keep going.

This is a nice, concise overview of some core, simple, practical functional concepts. I just want to make one note about your section on function composition. Notice at 16:33, Copilot suggests an implementation of the compose function for exactly 2 functions, which applies the functions in the correct order (based upon the mathematical definition of function composition). Specifically, the composition of functions f and g, which would be called as compose(f, g), first applies g (the right hand function) to an input (x), and then applies f to the result (i.e., compose(f, g)(x) == f(g(x))). However, the compose function that you instead implemented, taking any number of functions of type Composable, applies the functions in order from left to right, not right to left, because reduce traverses the list of functions from left to right. Therefore, your resulting compose function is not truly composing functions in the mathematical sense, and is generally called by other names in other languages (e.g., foldl or pipe) or even in existing functional Python libraries. For your compose function to behave similarly to the original Copilot suggestion, you would need to traverse the list of functions from right to left. This is also evidenced by the fact that in your original code leading up to your introduction of function composition, you had the expression (at 15:10) sort_fn(add_10(multiply_by_2(data))), but then (at 18:22) had to reverse the order of the functions in compose(multiply_by_2, add_10, quick_sort) to get the same result because your compose function applies the function in the reverse ("wrong") order.

The usage of AI while programming can lead to terribly wrong code. I know, you like it because of the speed, but the moment you trust it blindly, you have lost the game.

I’ve been working through boot .dev (backend training course online) and using as many functional approaches as possible to get my brain moving that way. Question, doesn’t that quick sort double the length of a normal quick sort as it has to check every element twice (once for greater than once for less than) as opposed to the two normal implementations that check through the list just once. I may be wrong.

I laugh at tutorial videos and people who watch them and think they are being productive wasting their time. When I was in a python network development internship, never ever found a video helping me, it was all going to documentation sites or asking people in forums. It doesn't matter cause like TechLead says, tech is almost dead nowadays, it just a skill for immigrants trying to immigrate in developed countries.

Sorry, but this is Just too fast for me, too many concepts in extremely quick succession. I don't tink that you used the Term idempotent correcty, If this means the Same AS the mathematical definition.

I've been doing a lot of the stuff in this video in Rust, it's nice to see a Python implementation of the same ideas which I can start to use in my day job.

I like raw sql. I don't want to fight a framework to get something done.

Thank you.

As always, it's another masterpiece. Thanks, Arjan. I believe the input ‘data’ at 20:09 could still be a list, instead of an iterator; Only the return needs to be an iterator In addition, we can still achieve the lazy evaluation 20:24 by simply using the result of the map function, without casting into a list

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Thanks a lot ! you are awesome, I randomly came acoross your channel when I was working on my first industrial software project, my code was working but suddenly I wanted to integrate database to the system, then I watch your video regarding events and design patterns, but I watch your video around 7 times before I implemented the technique on my code ... really greatful for your expertise, I just want see your old videos now. All the best wishes from Sri Lanka ! 👏👏👏

Worth noting that copy() only returns a shadow copy. So it's a new list but if the original elements were mutable (yours were ints at that's fine) then modifying them in the new list will also modify them in the old list. This can be a big gotcha in parallel code. Deepcopy from the copy module is _almost_ always what you need when you need an expensive copy.

Your point 3 needs a asterisk with the solition. The copy methid creates a shallow copy. Ehich means that if your liat contains anything that's passed by reference, it will be the same in the new list. If those mutable elements are changed in the new list, they will also be changed in the old list. For true immutability, the deepcopy functionality should be used.

What do you think of compose from the funcy-package? I've used it instead of writing my own compose-function.

Thank you Arjan for your helpful insights. I am a Mac newbie, coming from Linux. I've been developing an Android app in Kotlin, and now want to make it Multiplatform, so I bought a second-hand iMac with some reasonable specs. Now to learn a little Xcode / Swift ... wish me luck =)

I love the intro!

Do you use Rye?

Really enjoyed this video. The advanced concepts are appreciated.

I made a composable in my project recently, but it did not have type hint! I had the apply be a lambda, which is ugly IMHO. Then you solved it... but then another lambda appeared! I would want the return to be `partial(reduce, apply, functions)`! I will incorporate the type definition though!

Great vid as always, theres also *functools groupby*, which seems pretty powerful like... Sqlite3 backend, really doesnt matter, but i found like: ``` Select <record> from table where x, and y order by a,b ;``` Especially with um passing a method into the retrieval for how to create named tuples out of the list... you can get really ""complex"" behavior, with super performant code, thats also super readible. Ie used this in prompt generation for our tool, another thing im wondering about is separation vs interface vs api. For code that is being rapidly developped/iterated upon... (separation seems most important... i think.?)

pure function is not necessarily idempotent, these are two totally irrelevant concepts, not sure why you said that. 9:02

19:58 These both functions should take an Iterable as an argument, not an Iterator. Interpreter will automatically call for an iterator while using the for loop. Iterator protocol requires the __next__ method, which is not implemented for a list, for example. But the functions obviously can work with a list. We always should use the broadest types possible in for a function arguments and the most exact type for the result. This is known as the robustness principle, "Be liberal in what you accept, and conservative in what you return".

i still struggle to see the value of a compose function over a wrapper function that simply calls a series of functions sequentially. To me at least it feels much more readable and equally flexible. And if you rely on having so many arguments that in no longer remains readable it feels nicer to simply use a class instead. I do understand that the premise of the video is to utilise purely functional principles, but i really can't see a good use case for something like partial functions unless there's some underlying performance benefits. Even in languages like Go i mostly see the sequential approach against a struct of data which is also more readable imo. But then again i'm no expert in either languages, so that could just be lack of experience / use cases where this would make sense to apply

17:12 oh gods, they brought all that [T] cryptoshit from Java and C++ to my beloved Python. 😢

Recently tried out Gleam was super fun! Python is my main language so really cool to see these ideas in Python, great timing Arjan!

Is your Copilot suggesting lines you've already typed in a practice run before filming? Or does it not remember context in that way, and these are "fresh" suggestions?

Monad is insulted not being mentioned here

Nice video! The subtitles are a little bit out of sync though. Please fix that. Thanks.

0:28 "As a side effect..." I saw what you did there. Nice recursion example... quicksort is so much more likely to be used than factorial.

Love the mechanical keyboard 😂

Always great and understandable videos. Thanks 🥲

I rarely use recursion . Mostly to traverse a shallow tree like structure. Python has a recursion depth limit .

This is really spot on I was struggling with function composition for awhile