[ncmncm]

The point missed everywhere is that Rust lacks key language features needed to capture essential semantics in libraries, that C++ provides. To code libraries I want to code, I cannot use Rust. Rust cannot express them.

So, safety, good, fast enough, good, but insufficiently expressive? No, thank you.

[pdimitar]

It's probably missed everywhere because I at least have not seen anyone giving concrete info about which are these missing key language features.

Want to elaborate on that? Quite curious.

[rmadriz]

can you elaborate on those key missing language features ? You have commented multiple times about that, but haven't seen you giving any concrete example. I'm Genuinely curious.

[ncmncm]

Where to begin? Operator overloading. Programmed move semantics. Generics argument concepts. Look at the whole list of features C++ got since C++11, and subtract out the few of those Rust had or got.

[dannymi]

I've done a toy matrix library with operator overloading in Rust a while ago. Could you be confusing it with Java?

  #[derive(Debug, PartialEq, Eq)]
  pub struct ColumnVector<F, const DIM: usize>([F; DIM]);

  impl<F: Field, const DIM: usize> Add<Self> for ColumnVector<F, DIM> {
      type Output = ColumnVector<F, DIM>;
      fn add(self, rhs: Self) -> Self::Output {
          Self::new(self.0.zip(rhs.0).map(|(a,b)| a + b))
      }
  }

Usage:

  let v = ColumnVector::new([1.0,
                             3.0,
                             4.0]);
  let w = ColumnVector::new([1.0,
                             0.0,
                             4.0]);
  assert_eq!(v + w, ColumnVector::new([2.0,
                                       3.0,
                                       8.0]));

[pdimitar]

> Where to begin?

I propose you start with genuinely concerning problems. Operator overloading is a first-world problem and I've made a good career never depending on it (outside of my active C/C++ years at the start of it).

"Generics argument concepts" says exactly nothing, to me at least. Elaborate?

"Programmed move semantics" is, if I understand you correctly, a flavor / taste thing but I can agree it can be made better and more explicit -- say by not using the `=` operator for it. That I could stand behind. Still, it's only catching you off-guard while you're learning. 50/50 though. It's a concern but IMO not a major one.

And your final sentence betrays bias to C++. Well fine, use that, nobody is forcing you to work with Rust, right?

But if you're willing to bash Rust, please do so with concrete arguments. If you know something negative about it that I don't, I believe I and many others will benefit from informed objective criticism.

Do you have that? Already asked you in another comment and I'm still willing to listen to it.