Microsoft rewrote Q# compiler in Rust

[avestura]

It was previously written in C# and F#: https://github.com/microsoft/qsharp-compiler

[nwah1]

Was there a write-up of what the goals of the rewrite were, and why they switched the language and made the new engineering decisions?

[systems]

Well Rust was written OCaml on which F# was based So i think this was probably for performance, not for any expressive reasons

And personally i consider Rust to be from the OCaml/SML family of languages similar to F#, so i guess they moved within the family

[pjmlp]

I guess yet another minus for F# at Microsoft. Really funny how they manage it.

[FrustratedMonky]

So sad. Love F#, and Q# seemed like a natural extension, or at least brotherly.

At a high level, it seemed like F# is more functional like OCaml, than Rust is. I'd like to hear more about the reasoning, was it just performance? How different was it to justify a re-write?

[hu3]

> I'd like to hear more about the reasoning

My guess is because Rust is great with WebAssembly and they seem to target it with Q#:

https://github.com/microsoft/qsharp/tree/main/wasm

[FrustratedMonky]

This got me thinking of switching from F# to Rust, so did search and found this article that was good comparison. Others thinking of F# and Rust might dig.

https://jkone27-3876.medium.com/f-is-the-net-rust-62f71f8dae...

[adamnemecek]

Microsoft gets developer relations.

[zohvek]

https://www.youtube.com/watch?v=EMldOiiG1Ko&ab_channel=fb

tldr: developers

[Dudester230602]

Keep nerds around by letting them re-write things for no good reason?

[asylteltine]

Why not…just use rust then? I don’t understand the point of all of these niche languages in real life. Python, Go, rust, c, cpp, js, C#, kotlin, but why use others? Each of these have clearly defined strengths and community support.

[hu3]

While I understand your sentiment, Q# is specialized for Quantum Computing: https://en.wikipedia.org/wiki/Q_Sharp

It's arguably different enough of a domain to justify a new language.

[proc0]

There are multiple dimensions of trade-offs from which to choose from, i.e. runtime speed vs. convenience of writing, complexity of learning vs. powerful type systems, etc.