My favorite Rust function

Post by nerdponx » Sun, Oct 13, 2019, 6:14 AM UTC

saghm wrote: post #27

dbieber wrote: post #16

I haven't used rust, so can you explain this to me: If I do the rust equivalent of: def add1(x): return x + 1 x = 1 y = add1(x) z = add1(x) then will x have been deallocated by the first call to add1 and will the second call to add1 fail? [You can ignore the fact that I'm using numbers and substitute an object if that makes more sense in the context of allocating / deallocating memory in rust.]

Interestingly, the type of `x` actually does matter here in Rust! For most types, yes, passing something by value into a function will cause the memory to be "moved", which means that reusing `x` will be a compiler error. That being said, you can also either pass a shared reference (i.e. `&x`), which will allow you to access the data in Rust (provided you don't move anything out from it or mutate it, which would caus…

Post by enraged_camel » Sun, Oct 13, 2019, 6:21 AM UTC

jchw wrote: post #94

mav3rick wrote: post #84

Earlier quoted context omitted.

It is crippled admittedly by the authors themselves. The error checking pattern, no generics etc. are all to keep it "simple" yet are things most other programming languages have. Have you used Rust ? The borrow checker makes a lot of sense.

I feel like I shouldn’t have to answer this question, but Yes, of course I’ve used Rust. Why do you question this? I said nothing about Rust at all, other than that I like it, and whether Rust is good or not has little to do with Go being “crippled.” But of course, Rust is not flawless. In fact up until recently it was kind of annoying, before non-lexical lifetimes became a part of the language. It’s also a very larg…

Post by rumblefrog » Sun, Oct 13, 2019, 6:28 AM UTC

emptysea wrote: post #139

baby wrote: post #97

Earlier quoted context omitted.

I work with Rust only these days, it’s really an awesome language and I wish everyone working with system languages would switch to Rust. Yet, I find Golang to be a much clearer language to read (and I read a shit ton of code). I hope they don’t add generics, but I wish they would options, results, sum types in general, redeclaring variables, the ? Operator, etc.

How would Option , Result , and sum types work without generics?

Post by likeliv » Sun, Oct 13, 2019, 6:43 AM UTC

nerdponx wrote: post #141

saghm wrote: post #27

Earlier quoted context omitted.

Interestingly, the type of `x` actually does matter here in Rust! For most types, yes, passing something by value into a function will cause the memory to be "moved", which means that reusing `x` will be a compiler error. That being said, you can also either pass a shared reference (i.e. `&x`), which will allow you to access the data in Rust (provided you don't move anything out from it or mutate it, which would caus…

Is there any kind of compile-time check available for this (e.g. BIG COMPILER WARNING when you pass-by-value something that lacks Copy)? Seems like a lot of unsettlingly Python-esque freedom ("read the docs and don't screw up") for a language like Rust.

    let y = add(x.clone());
    let z = add(x);

Post by zozbot234 » Sun, Oct 13, 2019, 6:48 AM UTC

jchw wrote: post #22

> or making the language unacceptably crippled like Go Gotta say, I lost a lot of respect for the author at this point. It’s not like I don’t love Rust - quite the contrary - but if the only takeaway from Go for you is that it is “unacceptably crippled” then I feel you have missed a lot of insight. Go has been one of my languages of choice for over half a decade now, and for good reason.