wasm_utils

Utilities for working with Rust-exported wasm-bindgen types in JS environments.

Crates

Crate	Version	Description
wasm_refgen	0.2.0	Proc-macro that generates duck-typed JS reference boilerplate for wasm-bindgen structs
from_js_ref	0.2.0	Runtime traits (FromJsRef, JsDeref) for converting between JS reference types and Rust types

Quick Start

[dependencies]
from_js_ref = "0.2.0"
wasm_refgen = "0.2.0"

use wasm_bindgen::prelude::*;
use wasm_refgen::wasm_refgen;

#[derive(Clone)]
#[wasm_bindgen(js_name = "Foo")]
pub struct WasmFoo {
    inner: u32, // must be cheap to clone
}

#[wasm_refgen(js_ref = JsFoo)]
#[wasm_bindgen(js_class = "Foo")]
impl WasmFoo {
    #[wasm_bindgen(constructor)]
    pub fn new(inner: u32) -> Self {
        Self { inner }
    }
}

This generates a JsFoo type that can be used in function signatures, Vecs, and generics — places where wasm-bindgen normally can't accept exported Rust types directly.

use from_js_ref::FromJsRef;

// Convert from a typed reference
pub fn from_ref(foo: &JsFoo) -> WasmFoo {
    foo.into()
}

// Convert from a raw JsValue (duck-type validated)
pub fn from_value(value: &JsValue) -> Option<WasmFoo> {
    WasmFoo::try_from_js_value(value)
}

// Typed Vec support
pub fn from_many(foos: Vec<JsFoo>) -> Vec<WasmFoo> {
    foos.iter().map(Into::into).collect()
}

See the wasm_refgen README for detailed documentation.

License

Apache-2.0