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How I went about learning Rust

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Re: How I went about learning Rust

#161

Post by gary17the »

nicoburns wrote: post #140
dotancohen wrote: post #136

Earlier quoted context omitted.

As someone who even structures their Python in OOP, I'd appreciate elaboration on how you organize your Rust code. I've been glancing at Rust for far too long, never finding a weekend to dive in. Save me some headaches, how should I approach e.g. Customer - Product - Order relations without OOP? What is the canonical "Rust Way"?

Your customer, product and order are still going to be objects, but they won’t reference each other directly with references/pointers. Instead they’ll either store an id, or you’ll have a central registry of relationships using some kind of id (could be a key into a hashmap or an index into a vector) and then fetch data from the central store (or have the caller pass it in) at the last minute when running code that d…

> they won’t reference each other directly with references/pointers

I'm not sure if I understood your reply correctly, but there seems to be nothing in Rust stopping one dynamic trait (interface-based) object directly referencing another dynamic trait (interface-based) object. The main difference between C++ O-O and Rust trait-oriented programming is C++ inheritance of implementation vs. Rust inheritance of interfaces. You can also downcast in Rust, if you try hard enough.

https://gist.github.com/rust-play/fbe471b12a0fabe4ab7b653835...

Re: How I went about learning Rust

#162

Post by grey-area »

pizza234 wrote: post #96
zozbot234 wrote: post #76

Earlier quoted context omitted.

Rust actually supports most OOP features, with the main exception of implementation inheritance. And implementation inheritance is a nasty footgun in large-scale software systems (search around for: "fragile base class problem"), in a way that just doesn't apply to simple composition and pure interfaces (traits). So it's hard to fault Rust for including the latter and not the former.

> Rust actually supports most OOP features, with the main exception of implementation inheritance. I've tried some basic OOP. Fields from the base class need to be redefined in each child, and making shared methods private require an ugly workaround. Both concepts are very basic OOP concepts, not advanced or inherently/tendentially dangerous, and the results is that even basic Rust OOP requires a lot of boilerplate.…

Does OOP require inheritance?

Re: How I went about learning Rust

#163

Post by hurril »

AndrewDucker wrote: post #84
hurril wrote: post #77

Earlier quoted context omitted.

This sounds to me like the journey into functional programming. I've experienced the same thing myself.

I've encountered this pretty-much every time that I've learned a new language or framework. I start out trying to use it the way I've used things before, and then I slowly learn how the people who wrote it expect me to work, and then things get a lot easier.

That too and I don't think I'm even done with that, myself :)

What I meant is the step away from the notion that things are objects, stuff gets done with methods, methods are available via mixins/ inheritance/ magic, etc.

I've seen the notion of using values and pure functions as data oriented programming recently but never understood what that moniker adds.

Re: How I went about learning Rust

#164

Post by davidatbu »

nicoburns wrote: post #144
brobinson wrote: post #106

Earlier quoted context omitted.

Read about sum types. They exist in Haskell, Rust, OCaml, Typescript, Swift, Kotlin, etc. You are likely only familiar with product types without knowing they're called product types. (Cartesian product) You can have 100% type-safe, guaranteed at compile time code without null that can still represent the absence of data. Once you've used sum types, you feel clumsy when using Javascript, Python, Go, Ruby, C, C++, etc…

Arguably dynamic languages have sum types: every variable is one big sum type with the variants being every other type! I suspect the lack of sum types in many static languages are partially responsible for the popularity of dynamic ones.

Very interesting perspective!

Re: How I went about learning Rust

#165

Post by arwhatever »

thejosh wrote: post #43

I tried to pick up Rust a few years ago, but there were too many sharp edges. I thought it was a nice language, but was too early for actual use. I played with some libraries (Apache Arrow, etc) and it was nice. About 2 months ago I wanted to use Arrow within Elixir, which required me to start using Rust again (Elixir uses Rustler to safely convert from Rust Elixir without theoretically crashing the beam). I am amaze…

Indeed, I’m rereading The Rust Book , after struggling and finding slight success about around 2018, and am surprised at how much better the presentation is, as though they maintainers have closely studied where people got hung up, and then targeted those areas to add clarity.

I strongly suspect that it will stick this time.

Re: How I went about learning Rust

#166

Post by Barrera »

> Programming Rust (link to review) is the first book I read for an initial introduction to the language.

This book is very much under-rated. If you've unsuccessfuly tried to learn Rust by reading "the Book" cover to cover, you might try reading Programing Rust in the same way.

Re: How I went about learning Rust

#167

Post by jmartin2683 »

I love rust. I didn’t find it difficult to learn and at this point several others I’ve introduced it to also haven’t. I’m baffled as to where that reputation comes from.

I get that it makes you think about what you’re building a little more than something you can throw together like Python or Ruby but if the end goal is software that works correctly, getting there definitely isn’t harder with rust. It’s the complete opposite :/.

Re: How I went about learning Rust

#168

Post by nkozyra »

jmartin2683 wrote: post #167

I love rust. I didn’t find it difficult to learn and at this point several others I’ve introduced it to also haven’t. I’m baffled as to where that reputation comes from. I get that it makes you think about what you’re building a little more than something you can throw together like Python or Ruby but if the end goal is software that works correctly, getting there definitely isn’t harder with rust. It’s the complete…

> I’m baffled as to where that reputation comes from.

It's a deep language with a mix of borrowed syntax(es) and designs. You can pick up Go or Python or Nim in an hour and have a working application, that's fairly unlikely with Rust.

I'd say it took me a year to feel comfortable with Rust - to the point where I could just sit down and write applications without Googling every five minutes - which is far longer than I've spent with any other language.

Re: How I went about learning Rust

#169

Post by dllthomas »

pjmlp wrote: post #146
nicoburns wrote: post #142

Earlier quoted context omitted.

It definitely works differently to C++/Java/Python, but IMO this is one place where Rust is a huge improvement. You are effectively always generic over an interface (trait in Rust) rather than a base class, and this is much more flexible as a given strict can implement as many interfaces as it likes rather than being stuck in one class hierarchy (or having to deal with the pain of multiple inheritance)

It is no different than using interfaces, protocols, pure virtual base classes....

It's similar, but there are some differences. Notably, my package can implement my trait for your type, while my package (usually? always?) cannot make your type inherit from my virtual base class.

Re: How I went about learning Rust

#170

Post by prirun »

bbojan wrote: post #72
xEnOnn wrote: post #3

I have been thinking to myself whether I should pick up Go or Rust as a new language this year. Coming from a NodeJS background, Rust looks a tad more complicated but it looks cooler. There are also more job listings looking for Golang than Rust which makes me wonder if Golang might be a more rewarding investment? What would be a good use case of Rust than Golang cannot do given its extra complexity and potentially l…

One drawback of Go (in my opinion) is that it has a runtime. So it's very difficult (impossible) to use it with other languages that also have a runtime. So if you learn Go, you'll never be able to use it to interoperate with e.g. your Python program to speed it up. With Rust, you could use it to replace the most time critical parts of your high-level program piece by piece. The learning curve is then much easier, an…

> So if you learn Go, you'll never be able to use it to interoperate with e.g. your Python program to speed it up.

Never done it myself, but:

https://www.ardanlabs.com/blog/2020/07/extending-python-with...

https://github.com/go-python/gopy

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