js_class = "Blah" - The `wasm-bindgen` Guide

# `js_class = "Blah"`

The `js_class` attribute can be used in conjunction with the `method` attribute to bind methods of imported JavaScript classes that have been renamed on the Rust side.

    #![allow(unused)]
    fn main() {
    #[wasm_bindgen]
    extern "C" {
        // We don't want to import JS strings as `String`, since Rust already has a
        // `String` type in its prelude, so rename it as `JsString`.
        #[wasm_bindgen(js_name = String)]
        type JsString;

        // This is a method on the JavaScript "String" class, so specify that with
        // the `js_class` attribute.
        #[wasm_bindgen(method, js_class = "String", js_name = charAt)]
        fn char_at(this: &JsString, index: u32) -> JsString;
    }
    }