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How I went about learning Rust

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Re: How I went about learning Rust

#181

Post by pjmlp »

Ygg2 wrote: post #158
pjmlp wrote: post #147

Earlier quoted context omitted.

Yes it does, OOP is a spectrum not "like Java does it".

I'd consider something OOP if it has the same expressive power i.e. things expressible in OOP languages are easily expressible in another OOP language as well. And for Rust that's not the case. Otherwise you end up with Haskell is an OOP language.

I will debate it is one, yes.

Just like being an FP language isn't "like Haskell does it", when I learned FP, Haskell didn't even exist.

Try to express Eiffel, CLOS, SELF or BETA in Java.

By the way, here is One Weekend Raytracing in Rust, perfectly using OOP with dynamic dispatch and interfaces (sorry traits).

https://github.com/pjmlp/RaytracingWeekend-Rust

Re: How I went about learning Rust

#182

Post by pitaj »

synergy20 wrote: post #171

as an embedded c/c++ developer I tried Rust briefly a few times over the years, don't feel it's the right fit, due to the way it's static build by default the binary size is just too large, plus the library pool is still much small, and there is no equivalent to c++'s STL for speedy coding when I need it. yes I can trick for size etc, but overall it just did not fit well so far, for the embedded space that is, but, '…

But that's just the default, you can tell it to use dynamic linking. What libraries were you missing? I find the rust standard library is better in many ways, and it doesn't have the same performance footguns.

Re: How I went about learning Rust

#183

Post by nicoburns »

gary17the wrote: post #161
nicoburns wrote: post #140

Earlier quoted context omitted.

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 interface…

You can do references in Rust. But you can only have one mutable reference to an object at once unless you work around this with locks (Mutex, RefCell, etc). So for anything other than trivial child object references, you can quickly paint yourself into a corner of compilation errors by using webs of references. And this seems to be the basis of a lot of people's frustrations with Rust.

It's true that you also can't do inheritance. But I've found this tends to be less of a problem as most OOP languages encourage composition over inheritance anyway, and composition works the same in Rust as in other languages.

Re: How I went about learning Rust

#184

Post by pjmlp »

grey-area wrote: post #162
pizza234 wrote: post #96

Earlier quoted context omitted.

> 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?

Kind of, it needs the ability to express polymorphism and extend concepts.

Now how that is done is practice, can be done in various ways.

Class inheritance, which is what many think of.

Interface inheritance or conformance, which is available in many languages via traits, patterns, data classes, functors, or other names, and OS ABIs like COM.

Prototype inheritance, clone a instance and monkey patch in place (like SELF)

Via composition and delegation for not handled messages.

Then many languages offer a combination of those approaches.

Re: How I went about learning Rust

#185

Post by thesuperbigfrog »

Fiahil wrote: post #145
Jyaif wrote: post #62

Earlier quoted context omitted.

> Rust is a better c++ The Rust language is a far better C++. In practice, the compile time and binary size of Rust are out of control, which makes Rust far from being a slam dunk over C++. Crossing my fingers this will change!

As of Rust 1.62, compilation time is no longer a valid criticism. Things have improved so much in the past 2-3 versions, it's no longer slower than C++. Sorry!

>> As of Rust 1.62, compilation time is no longer a valid criticism. Things have improved so much in the past 2-3 versions, it's no longer slower than C++. Sorry!

Is there a report or study somewhere that shows how much it has improved?

I had heard improving compilation and build time was being worked on, but I don't get to use Rust much in my current work.

I would be interested to see how much improvement has been made and in what areas.

Re: How I went about learning Rust

#186

Post by arunc »

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.

Aside from the awesome community that rust has, don't underestimate the power of marketing. Someone should ask Mozilla how much was spent for rust development.

Sun microsystems spent about $500 million in 2003 to push forward Java. https://www.theregister.com/2003/06/09/sun_preps_500m_java_b...

Re: How I went about learning Rust

#188

Post by synergy20 »

pitaj wrote: post #182
synergy20 wrote: post #171

as an embedded c/c++ developer I tried Rust briefly a few times over the years, don't feel it's the right fit, due to the way it's static build by default the binary size is just too large, plus the library pool is still much small, and there is no equivalent to c++'s STL for speedy coding when I need it. yes I can trick for size etc, but overall it just did not fit well so far, for the embedded space that is, but, '…

But that's just the default, you can tell it to use dynamic linking. What libraries were you missing? I find the rust standard library is better in many ways, and it doesn't have the same performance footguns.

I don't feel Rust has any performance advantage to c and c++ per my own tests.

yes I can dynamically link to stdlib in Rust but I don't think Rust has a versioned dynamic library released for multiple architectures(still many embedded archs are not fully supported in Rust), that leads to problems in the field at depolyment and upgrade phases. Plus the dynamic library after strip is still close to 6MB, I can have a full libstdc++ around 2MB for the embedded system(with musl it is about 1MB), for many low-range embedded systems(there are a _lot_ of them), 6MB is still quite large.

Re: How I went about learning Rust

#189

Post by cercatrova »

memorable wrote: post #148
gg2222 wrote: post #128

Earlier quoted context omitted.

What Rust web libraries/frameworks do you use and recommend? How long does your Rust project take to compile?

I'm not the OP, but I liked Warp[0] the most. Actix Web is cool, but looks ugly and hard to use. Rocket doesn't even work. And Tide is lean and clean, but its examples and codes aren't as well-made as Warp. [0]: https://github.com/seanmonstar/warp

Have you tried axum? It's by the Tokio organization, newer than the others.

I still use actix-web though since I found it way easier to parse than axum or warp, in my opinion. The minimal examples for each make actix-web the most readable for me.

Re: How I went about learning Rust

#190

Post by cercatrova »

mprovost wrote: post #113
zozbot234 wrote: post #28

Earlier quoted context omitted.

Since you're coming from a NodeJS background, you'll want to pick up an introductory textbook about C as well. Rust implicitly relies quite closely on the C machine model, and introductory books about Rust (such as "The Rust Programming Language") don't do a very good job of conveying the nitty-gritty details of that model to novice coders. This is a pretty nasty pitfall when trying to code in Rust, and it's importan…

I'm self-publishing "Rust From the Ground Up" which takes this approach: each chapter rewrites a classic Unix utility (head, cat, wc, ...) from the original BSD C source into Rust. I find for systems programming it's easier to understand how things work in C, and then teach the idiomatic way of doing it in Rust. C is pretty easy to follow along in "read-only" mode with some explanations. https://rftgu.rs/

Interesting, seems similar to the book Command Line Rust which also teaches you by reimplementing Unix commands, any thoughts on the differences?
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