rune

An embeddable dynamic programming language for Rust.

Contributing

If you want to help out, there should be a number of optimization tasks available in Future Optimizations. Or have a look at Open Issues.

Create an issue about the optimization you want to work on and communicate that you are working on it.

Highlights of Rune

• Clean Rust integration 💻.
• Memory safe through reference counting 📖.
• Template strings 📖.
• Try operators 📖.
• Pattern matching 📖.
• Structs and enums 📖 with associated data and functions.
• Dynamic vectors 📖, objects 📖, and tuples 📖 with built-in serde support 💻.
• First-class async support 📖.
• Generators 📖.
• Dynamic instance functions 📖.
• Stack isolation 📖 between function calls.
• Stack-based C FFI, like Lua's (TBD).

Rune scripts

You can run Rune programs with the bundled CLI:

cargo run -- scripts/hello_world.rn

If you want to see detailed diagnostics of your program while it's running, you can use:

cargo run -- scripts/hello_world.rn --dump-unit --trace --dump-vm

See --help for more information.

Running scripts from Rust

You can find more examples in the examples folder.

The following is a complete example, including rich diagnostics using termcolor. It can be made much simpler if this is not needed.

use rune::termcolor::{ColorChoice, StandardStream};
use rune::EmitDiagnostics as _;
use runestick::{Vm, FromValue as _, Item, Source};

use std::error::Error;
use std::sync::Arc;

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
    let source = Source::new(
        "script",
        r#"
        fn calculate(a, b) {
            println("Hello World");
            a + b
        }
        "#,
    );

    let context = Arc::new(rune::default_context()?);
    let options = rune::Options::default();
    let mut warnings = rune::Warnings::new();

    let unit = match rune::load_source(&*context, &options, source, &mut warnings) {
        Ok(unit) => unit,
        Err(error) => {
            let mut writer = StandardStream::stderr(ColorChoice::Always);
            error.emit_diagnostics(&mut writer)?;
            return Ok(());
        }
    };

    if !warnings.is_empty() {
        let mut writer = StandardStream::stderr(ColorChoice::Always);
        rune::emit_warning_diagnostics(&mut writer, &warnings, &unit)?;
    }

    let vm = Vm::new(context.clone(), Arc::new(unit));

    let mut execution = vm.call(&["calculate"], (10i64, 20i64))?;
    let value = execution.async_complete().await?;

    let value = i64::from_value(value)?;

    println!("{}", value);
    Ok(())
}