Rhai - Embedded Scripting for Rust

Rhai is an embedded scripting language and evaluation engine for Rust that gives a safe and easy way to add scripting to any application.

Supported targets and builds

• All common CPU targets for Windows, Linux and MacOS.
• WebAssembly (WASM)
• no-std

Features

• Easy-to-use language similar to JS+Rust with dynamic typing.
• Tight integration with native Rust functions and types, including getters/setters, methods and indexers.
• Freely pass Rust variables/constants into a script via an external Scope.
• Easily call a script-defined function from Rust.
• Fairly low compile-time overhead.
• Fairly efficient evaluation (1 million iterations in 0.25 sec on a single core, 2.3 GHz Linux VM).
• Relatively little unsafe code (yes there are some for performance reasons, and most unsafe code is limited to one single source file, all with names starting with "unsafe_").
• Re-entrant scripting engine can be made Send + Sync (via the [sync] feature).
• Sand-boxed - the scripting engine, if declared immutable, cannot mutate the containing environment unless explicitly permitted (e.g. via a RefCell).
• Rugged - protection against malicious attacks (such as stack-overflow, over-sized data, and runaway scripts etc.) that may come from untrusted third-party user-land scripts.
• Track script evaluation progress and manually terminate a script run.
• Function overloading.
• Operator overloading.
• Organize code base with dynamically-loadable modules.
• Scripts are optimized (useful for template-based machine-generated scripts) for repeated evaluations.
• Support for minimal builds by excluding unneeded language features.

Documentation

See The Rhai Book for details on the Rhai script engine and language.