RUST Enums ARE Better 

first, also hey, let me know what you think about this code video? I tried to make LOTs of code, but cool and exciting. (also like the video, ty ty :))

I feel so hyped to learn Rust every time you make a video on it

I really love this new style with showing the ctode, great video!

I love clear Result/optional types, these are soo much better then exceptions!

Oh my God, these animations and the code presentations are God tier! What the fuck is this super high quality!!! Also the explanations are top notch. The video is amazing! 10/10

Seems very similar to language features from the FP world, specifically OCaml. The match functionality with extracting out data from container values is so powerful that it serves as the basis for most algorithms in OCaml. It’s pretty cool to see so many languages adopting FP language features like Python and Rust taking matching.

Prime, I loved this style of comparing code. Really, really helps and also really dig that colour scheme;)

I am currently doing my CS undergrad and we are doing a one-year-long team-programming exercise. We have to do this in Java and in our code we basically have multiple enums that are templates to build functions out of. The hoops you have to jump through to make this a reality in Java are insane (we ended up coding a bunch of Factories) and I am quite jealous that it does not work like in Rust.

enum RealProgrammingLanguages { Rust, Haskell }

I know this concept from Haskell and Swift. They‘re great! I really hope, that there will someday be an equivalent in TS

Woah Prime! Calm down there! If you continue like this I'll end up learning rust

Hey Prime! loved the vid. One quick question, what software do you use to edit your coding videos like this?

Waiting for more Rust jobs, to finally switch from TypeScript to Rust. I love TypeScript sooo much, I written lots and lots of code during 5 years of my career, but Rust seems to me to be my next step

This type of format is so good. I feel that re-watching the video does not tire me at all if I don´t get the concept in the first run.

Also pretty cool is that Option (which would be the same as a nullable pointer) actually is represented as a single nullable pointer in memory, since rust knows that the pointer (Box) cannot be null, and therefore uses null to represent None.

I remember learning how Rust enums can hold a subtype and it blew my mind.

Great video, as usual! The editing on this one however is next level. Well done! Really easy to follow! Good job! Keep up the good work!

Did you use some software to edit the code slides, or was this done by your editor?

You can use typescript enums to enforce that each case is matched. It's not on by default which would be nice, but you can get it to give you a type error by sending the variable you're switching over to never. function getColorName(c: Color): string { switch (c) { case Color.Red: return "red"; case Color.Green: return "green"; // Forgot about Blue default: const exhaustiveCheck: never = c; throw new Error(`Unhandled color case: ${exhaustiveCheck}`); } }

Great videos man. Would love to see some on meta skills like your process of learning and how to develop deep understanding of these abstract systems

What software you used to show the code? Is the same as code aesthetics? Just curious. I really liked it.

Nice video! On the array example, am I right that this is demonstrating the difference between structural and nominal typing, and how the latter is stricter?

I wondered what tool did you use for the code animations? Great video 🙂👍🏻

It's really crazy how readable rust can be if you don't try to get too fancy. Loving getting to work with TS and Rust on my 2 projects right now

The result types feel similar to Java checked exceptions. Interesting, in general I think the industry moved over to unchecked exceptions due to the caller not being able to handle properly all the possible exceptions. Seems like in Rust this works better I suppose? Also was glad to see that Kotlin enums share some similar traits as Rust which is neat. Great job with the code highlighting Prime! Did use any programs to achieve this darken / focus effect on the code?

This feels pretty similar to Java enums. What I like about Rust's approach is having errors propagate as values, since like you said, you know exactly what you're getting just from the return type including potential errors

Holy crap. Just came across your channel. Love the production and content quality. Subbed!

My favorite part about result is that you can make your own error type that you can implement Into for - meaning you can seamlessly turn a random imported error type into your own with minimal code and clutter (usually *less* clutter)

a fun, random fact about rust enums: if you want to have an "any" type (i.e. retrieving a value from a database store), you can use it in order to map db types to rust types. this is how surrealdb handles query values internally for each column

Hey Prime, nice video. Have you ever tried Haskell? I would be curious what you thought of it. Rust has so much momentum now and I wish some other really cool languages like Zig, Haskell, or even Common Lisp or Clojure could get some love from a big voice.

While this video may not be the best performing video, the knowledge packed into it is stellar. Thanks for making it Prime.

Pattern matching in Elixir is even more mind blowing.

I like to think of Rust enums as C unions. I know it's not a one-to-one comparison but I think it makes the most sense

For 0:36, I cover this issue with the `@typescript-eslint/switch-exhaustiveness-check` rule in eslint. It would be ideal if it was a TypeScript warning or option, but I think most TypeScript devs use eslint anyway so I don't think it's a big issue

Prime, is this video part of an upcoming Rust For TypeScript Devs course. Amazing explanations, as always. Thank you.

FWIW, you can get exhaustiveness checking in TS switch statements by using something like default: notReachable(value); where function notReachable(value: NoReturn): NoReturn {} Anyway, algebraic data types FTW. Glad languages like Rust are looking at functional languages for inspiration.

How'd you animate all those fancy text comparisons?

A fix to the scalability issue you mention with traditional enums is to make an X macro that expands into a static array. This way, it is impossible to miss a single enum type. Then, you don't need a function, rather index into the static array using the enum name to yield its value.

I think you should mention exhaustive switches in typescript via function assertUnreachable(x: never): never { }. It would also make a lot of sense to mention tagged union types in typescript which brings it closer to rust enums.

Thank you very much for the Inspiration and motivation you give me / us trough youre wonderfull blaizinglyyyyyyy fast videos !!! I love you're vibe !

Beautiful video! I’d recommend slowing down a tad bit tho, felt like you were going too fast at times

hi primagen, do you mind sharing the language you write mostly at netflix?

I did the rustling exercise(not all of it yet) and I really like how enums are used in match cases and results. I never even thought of using them in a vector though

> Who handles the error? This is why I fundamentally abhor exceptions for error handling. Every time I try to catch exceptions without resorting to `catch (BaseException e)`, assuming the language has one base class for exceptions, I always find one undocumented and uncaught exception that crashes my app, because the only way to find all the exceptions thrown is to read all the functions you call, and all the functions those functions call, and all the functions those functions call, ad nauseam.

Thanks for highlightning interesting parts. Rust looks really promising. Regarding exceptions, if I get you right, there is interesting opinion on forcing explicitly manage exeptions. Article is The Trouble with Checked Exceptions

Dang! I didn't know enums could have methods in Rust. That's pretty cool. As a casual Rust dev, I find it hard to discover some of the rare pearls of Rust like this one. You just have to know that this feature exists. I have never heard of methods on enum in any other languages, making hard to look for this. Even if I already knew 95% of what you talked about in your video, the enum part blew my mind. Thanks Prime for doing these kind of videos. I really like the content you create. Keep it up!

The video was entertaining and educational at the same time, Well Done! 😄

Thank you for providing this comparison of Rust and JavaScript! Your perspective has inspired me to create my own videos on the topic. Thanks, see you soon! 💪

Looking at this, coming from Swift to Rust might actually be way easier than I thought. This sounds exactly like Swift enums, even Optional is basically enum { case none, some(T) }

in the first example switch statement make sense; what if you dont want yellow to do anything? you still have to add it but then immediately break?

Don't forget let else, which landed recently. It's the early return guard version of if let, although it lets (heh) you do other things as well. And it moves so much code to the left.

What do you use for the code part of the video?

ThePrimeagen, I am learning rusting to create a cross platform app. I'm thinking of using rust for the backend. For the front end, should I rely on a Javascript framework or a rust framework like Dioxus?

Rust is just such a well-designed language in general, and enums are a great example. Rust's enums are a combination of the classic enum concept of associating a constant int with a defined string to constrain values to a range of valid values, mixed with the idea of a union type, where you can have one variable that can hold multiple types of data. Most mainstream languages have seriously sucked at handling union types properly. Typescript somehow manages to even screw up the constant to act as a value constraint part too.

the second point you brought up about Item and string seems to be based on the duck-typed nature of TS. TS must be duck-typed because the types don't exist at runtime, so you can only assure that types are compatible with each other, but not actually the correct instances (unless you use prototypes/classes). so i think this applies to every statically typed language, not just TS. maybe not a fair comparison?

legit a great video. I do feel bad that it's doing not doing as well as your other ones. I share your pain in that regard.

You would well fit into an aula giving a lecture to a whole class and each student would come out understanding what they have just learned

Awesome Prime, bring more differences and why Rust is better!!! First look enums seems the same in TS and Rust, but know I now there's a huge difference!!

damn, I was just learning these yesterday. As a typescript dev I am really loving the rust enums so far, especially the pattern matching!

JS->TS->Rust pipeline let's gooo. Love this kind of content from your channel.

You should have mentioned the feature of forcing non exhaustive pattern matching on an enum. It is done in libraries where you want to have the option of adding more variants without breaking users' code. #[non_exhaustive] enum MyEnum{...}

This was so entertaining to watch!! :) thanks for this sweet delicacy of content! I can tell you put a lot of effort into them no doubt

How do you choose between result parameterized by option and vis versa

Simply amazing. You do explain very well, thank you for these videos and again, I'm super hyped to get back to Rust hshshshshs

Thumbnail is really good! It was satisfying to my eyes and rust enums are the best

The rust enums often remind me of Kotlin sealed classes, I know their are not fundamentally the same thing, but the experience in using them is somewhat similar. You should take a look at Kotlin, it's a really powerful language and great for backend dev (expecially with ktor ;)

Very nice presentation! Loved the commands being highlighted and everything.

The code animations/highlighting are on point. Super fun to read

I really wish the tech-fluencers take inspiration from this much effort into putting such a valuable lesson for us. I would really wish that you publish writings using GPT if you find it helpful for speed for publication. I would love to read code-oriented and example-oriented style in blogs. It really makes it easier for me to "fork" the examples and consume it in my own notes, while allowing you to funnel to potentially a wider audience. No, this comment is not GPT-generated, and I nor did I tell it to explicitly write like I'm 13 years old

Rust is brilliant. This error handling however does put a lot of boilerplate match/if statements. But I agree its better than debugging random crashing & failures.

Would LOVE a video on how you manage to work full time, run a twitch and yt channel, and learn and work on your skills. All while having 4 kids and a wife!? I struggle harddddd to find more than 2-3 free hours per week and i’m a senior dev with a wife and 2 kids. Would love to know how you organize your time and make it all happen!

You and the "No Boilerplate" channel have gotten me so interested in trying Rust

Love this format, more videos like this please 🙏🏽

love how you showed the code, i think if you took more breaks to clarify everything it would be even better, (like okay this is what we did up to this point) lovin it tho

Pretty neat explanation about how Rust Enums are superior to Typescript Enums and also its type system in general. I wouldn't say it's Typescript's fault as it tries to solve an issue to a language that wasn't made with Types in mind. And second, about the presentation style, animations, etc, gorgeously and simple, not bloated with crazy animations; highlighting side by side TS and equivalent in Rust was really nice. 10 out of 10 for this presentation and explanation

Enums in rust sound a lot like structs, a type that hold some data and you can define methods on those types. Is there some fundamental difference between structs, in Go for example, and enums in rust?

Java tried to do the Result thing with checked exception, but nobody like that

Have you ever tried elm for front end? It's also strict toyed language and I think someone who loves types in Rust must love elm

It's also worth mentioning (i don't know about TS), that rust enums are ADT-sums and you can have aribatary data inside variants, in most languages like c++ enum is int with name

Switch and enums in TypeScript won't have exhaustive checking like match and enums in Rust. However, using enums with records will. For example ``` enum Color { Yellow = 'Yellow', Red = 'Red', Green = 'Green', Blue = 'Blue', } type CanPrint = { print: () => void } type ColorRecord = Record const printColor = (color: Color) => { const colors: ColorRecord = { [Color.Red]: { print: () => console.log('red') }, [Color.Green]: { print: () => console.log('green') }, [Color.Blue]: { print: () => console.log('blue') }, } colors[color].print() } ``` Here Typescript will do an exhaustive check of the enum variants. Since Color has a `Yellow` variant in the enum `const colors` will give you a typescript error like: ``` Property 'Yellow' is missing in type '{ Red: { print: () => void; }; Green: { print: () => void; }; Blue: { print: () => void; }; }' but required in type 'ColorRecord'. ``` Still nothing as great as Rust, but nothing usually is.

Nice video man, I always used enums anyways. Whats the colorscheme btwm

what is the font in your terminal?

I'd say the "string | number | Custom" type isn't quite equivalent to the Rust's enum, because there are no primitive variants in the Rust example (since that is not possible, which why we need to wrap the value type). You can think of each variant as its own type that can wrap around their associated values. It would be more correct to say type Item = Foo | Bar | Baz; Where any variant Foo, Bar and Baz are typed as: type Foo = { kind: "Foo"; // Discriminator value: string; // Bar = number, Baz = Custom } This way we also avoid the issue with pushing strings to the array. You could think of this as being similar to the more verbose version in Rust: enum Item { Foo { value: String }, Bar {.value: usize }, Baz ( value: Custom } } Albeit with extra step of defining the discriminator manually.

Sick editing, great video 👍

Swift also has all these features with enumerated & you’d be surprised how much easier everything is to maintain when using enums this way. The possible permutations are logically sealed & so it’s very hard to miss things if you base your foundation of workable items in enums. The best kind of code is the kind that won’t compile if you do something the system isn’t meant to do.

Prime, what about Java or C# do you not like and prefer Rust over?

This reminds a lot of c#, it has pattern matching though it’s still called switch, and extension methods which lets u define functions in a similar way to “impl”, and most importantly flag enums, not sure if rust has flag enums, but it seems stupid not to

That `if let = value { true } else { false }` can even be shortened with the `matches!` macro which does just that: `matches!(value, )`

I watched this because you mentioned being disappointed in the performance of the video somewhere else. While there's a audience for it, I think it hits this weird duality of "I already know what this is" and "I can't even guess what this is." Probably the best hook is going to be "I know a little and want to know more." Just my two cents. For me this is all just haskell but verbose (not that I'm in love with Haskell). Sum types and verifying correctness of the program and pattern matching... it's neat but it can be such a pain to refactor or rearrange. At least in Rust you print a message without having to pollute your whole program with Effect monads XD I'm still on the fence about types, I like them in C where they have real meaning about the memory you're working with, but I never feel rescued by them. They can never be perfect and there's this whole spectrum of how painful you want them to be versus how effectively they will reveal bugs and the balance just never hits the right mark for me. I'm very Rich Hickey on it, I want to be able to amend my software easily without changing existing behaviour, I don't want types to guide me through making breaking changes that are going to leave behind bugs regardless. I just hate brittle software that needs a million changes when no functionality actually broke. Don't know if any of that makes sense, but cheers anyway I love your videos

You are the reason why I started learning Rust and I have to say it’s so damn good

On a side note can we all agree that the “break” keyword in a switch statement is one of the dumbest language designs for any language. I can count on one hand the times I needed fall through after matching. It should be the opposite where if you want fall through after matching then “continue” is required.

One of my favorite enums is Ordering. So easy to read.

bruh, if you make this a series I might have to learn rust

a more semantically equivalent version of the Item type from typescript would technically be a ``` union Item { foo: String, bar: usize, baz: Custom } ``` though it is more semantically equivalent because it has a lot of the same issues as the typescript version, as well as being much more unsafe to actually use.

Rust enums come from OCAML, but I think that the syntax probably came from Haxe. They are a way to make a discriminated union (each variant occupies the same memory, but only 1 variant can be accessed, and that is based on the discriminant, which tells you which variant currently occupies the area.

These comparisons are a really good way to convince people to learn rust. I am a Frontend dude, I use Typescript, I hate it but I use it because it's better than plain JS but I still hate it.

Rust is 👑. Rust is life. Oxide everything. Blazingly rusty. 🦀

See, I've gone ahead and learned Rust and although i knew a bit of Python and JS, I was no where near proficient. I am getting pretty good at Rust now and am quite worried that no other language will be as satisfying. The Enum type is just magical, it makes handling errors sooooo damn easy, oh what will I dooooo

Preach it bro! For a future where we spend more time building and less time debugging!

You can make ts enum switch case to also throw an error if not all cases are handled by using never in default. Even despite this fact rust enums is still much better since you don't need to remember to always include default, and not just that. enum Color { Red, } function test(x: Color) { switch (x) { case Color.Red: return; default: const test: never = x; } }