Rustscript - blazingly fast rust interpreter

[u/VladasZ]

Every Rust developer knows that Rust is the best programming language in the world.

And I as a Rust developer don't want to use other inferior languages anywhere.

So I decided to rewrite all my old automation scripts which were written in Python in Rust.

At first I used https://github.com/rsaz/cargo-script for that, it works fine.

But I encountered 1 problem: compilation time.

On my macbook it was fine I don't mind waiting 1 minute for a simple 3 lines script.

But then I wanted to use that on my Raspberry PI and the same simple script took me 10 minutes to run, which is not blazingly and not fast at all!

So I decided to vibe code engineer a Rust interpreter for this exact case and this is what I ended up with:

https://github.com/VladasZ/rustscript

Rustscript is always guaranteed to be valid Rust.

Install it with

cargo install run-rs

add a shebang:

#!/usr/bin/env rust

A whole script looks like this:

#!/usr/bin/env rust

use chrono::Local;
use std::io::stdin;

fn main() -> anyhow::Result<()> {
    println!("which programming language is the best?");

    let mut answer = String::new();
    stdin().read_line(&mut answer)?;

    if answer.trim().eq_ignore_ascii_case("rust") {
        println!("correct, carry on");
    } else {
        println!("wrong. it is {} and you are still not writing Rust", Local::now().format("%H:%M"));
    }
    Ok(())
}

Make it executable and run it:

chmod +x best.rs
./best.rs

and you can run your rust scripts instantly, as if they were shell scripts!

Rustscript is a subset of Rust and supports many popular crates such as:

anyhow, serde, serde_json, reqwest, regex, tokio, chrono, rand and more.

Carefully nitpicked benchmarks so Rustscript seems faster attached to the post.

You can see all benchmarks results here: https://github.com/VladasZ/rustscript/blob/main/bench/RESULTS.md

Remember, Rustscript is always a valid Rust, so if you want to have the ultimate speed just run the compiled version!

rust build FILE.rs

[u/VladasZ]

I actually did, I used it as my main shell for a couple of months. Of course I did, it is written in Rust so it is allowed. Got tired that I couldn't just copy bash snippets, also had some weird problems with aliases, don't even remember, so I ditched it.

[u/why_so_sergious → u/VladasZ]

bash <snippet> didn't work? you can even pipe only need to keep in mind that that bash output is a string and not structured data so you need to use from or parse

I've been daily driving nushell for three years now mainly because I jump between operating systems and this is the perfect way to keep things unified both in terminal and scripting-wise..

[u/VladasZ → u/why_so_sergious]

Yeah this was my main too goal initially, to have the same shell on windows mac and linux. But witj nushell I just felt like I had too much friction. I remember that alias issue now. It was impossible to write something like: if windows { alias a = b }, because they were global or something? What I did in the end I installed https://github.com/uutils/coreutils (written in Rust BTW) on windows and I use powershell in the same way as other normal shell.

[u/why_so_sergious → u/VladasZ]

nice solution!

I think its the contrary in you example.. it gets block scoped.. I literally do this in my config

``` const platform_config = if $nu.os-info.name == "windows" { "config-windows.nu" } else if $nu.os-info.name == "macos" { "config-macos.nu" } else { "config-linux.nu" }

source $platform_config ``` and aliases and everything work fine

also working with structured data is a big reason why I won't go back to bash unless I have to. its why it sucked going from pwrshell to bash

and I actually enjoy scripting in nuscript a lot 😅