rune 0.6.12

# rune

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<br>

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][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.

<br>

### Highlights of Rune

* Clean [Rust Integration 💻][support-rust-integration].
* Memory safe through [reference counting 📖][support-reference-counted].
* [Template strings 📖][support-templates].
* [Try operators 📖][support-try].
* Pattern matching [📖][support-patterns].
* [Structs and enums 📖][support-structs] with associated data and functions.
* Dynamic [vectors 📖][support-dynamic-vectors], [objects 📖][support-anon-objects], and [tuples 📖][support-anon-tuples] with built-in [serde support 💻][support-serde].
* First-class [async support 📖][support-async].
* [Generators 📖][support-generators].
* Dynamic [instance functions 📖][support-instance-functions].
* Stack isolation between function calls.
* Stack-based C FFI, like Lua's (TBD).

<br>

### 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

```rust
use rune::termcolor::{ColorChoice, StandardStream};
use rune::EmitDiagnostics as _;
use runestick::{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, &mut warnings, source) {
        Ok(unit) => unit,
        Err(error) => {
            let mut writer = StandardStream::stderr(ColorChoice::Always);
            error.emit_diagnostics(&mut writer)?;
            return Ok(());
        }
    };

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

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

    let mut execution: runestick::VmExecution =
        vm.call_function(Item::of(&["calculate"]), (10i64, 20i64))?;
    let value = execution.async_complete().await?;

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

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

[future-optimizations]: https://github.com/rune-rs/rune/blob/master/FUTURE_OPTIMIZATIONS.md
[Open Issues]: https://github.com/rune-rs/rune/issues
[support-rust-integration]: https://github.com/rune-rs/rune/tree/master/crates/rune-modules
[support-reference-counted]: https://rune-rs.github.io/rune/variables.html
[support-templates]: https://rune-rs.github.io/rune/template_strings.html
[support-try]: https://rune-rs.github.io/rune/try_operator.html
[support-patterns]: https://rune-rs.github.io/rune/pattern_matching.html
[support-structs]: https://rune-rs.github.io/rune/structs.html
[support-async]: https://rune-rs.github.io/rune/async.html
[support-generators]: https://rune-rs.github.io/rune/generators.html
[support-instance-functions]: https://rune-rs.github.io/rune/instance_functions.html
[support-dynamic-vectors]: https://rune-rs.github.io/rune/vectors.html
[support-anon-objects]: https://rune-rs.github.io/rune/objects.html
[support-anon-tuples]: https://rune-rs.github.io/rune/tuples.html
[support-serde]: https://github.com/rune-rs/rune/blob/master/crates/rune-modules/src/json.rs