3 releases

0.9.5 Aug 9, 2021
0.9.4 Aug 9, 2021

#390 in WebAssembly

32 downloads per month

MIT license


Rust bindings for Yare.io bots

crates.io docs.rs

This crate uses wasm-bindgen to expose the objects available to Yare.io bots to Rust. It's meant to be used with yareio-rust-template, which contains custom build scripts necessary to make wasm-bindgen work with Yare.

This crate is documented with Rustdoc.

This crate is compatible with TypeScript, but you will need to use the TypeScript types from yareio-typescript-typings.

See also yare-rust for an alternative to this crate.

Usage notes

The methods and structs this crate provides map pretty directly to what's available in JS. This means they won't always be idiomatic Rust. For example, Deref-based inheritance is ued extensively; this is an antipattern for idiomatic Rust but it's also the most performant way to represent JS inheritance hierarchies, and it's what wasm-bindgen uses. The idiomatic alternative would be to use trait objects, but this would add additional dynamic dispatch on top of what JS already does, making it slower.

Passing values between WebAssembly and JS is slow, especially when those values aren't numbers. Generally, any method in this crate that returns a value involves such a transfer of data (functions that return static references don't). So be careful, and only retrieve the information you need.

For the reasons mentioned in the previous paragraphs, you may want to create you own structs and data structures to store the information you need.

Shape features

To access shape-specific methods like merge(), jump(), and explode(), you'll need to enable the crate feature corresponding to the shape you play with in your Cargo.toml. The available shape features are circles, squares, and triangles.


This crate has a prelude module that re-exports the most useful items. You can bulk-import them all with

use yareio_sys::prelude::*;

RenderService bindings

This crate optionally provides bindings for yare-code-sync's RenderService, under the render_service module. You will need to enable the crate's RenderService feature to use these bindings.


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