js_namespace = blah

This attribute indicates that the JavaScript type is accessed through the given namespace. For example, the WebAssembly.Module APIs are all accessed through the WebAssembly namespace. js_namespace can be applied to any import (function or type) and whenever the generated JavaScript attempts to reference a name (like a class or function name) it'll be accessed through this namespace.

# #![allow(unused_variables)]
#fn main() {
extern "C" {
    #[wasm_bindgen(js_namespace = console)]
    fn log(s: &str);

log("hello, console!");

This is an example of how to bind console.log in Rust. The log function will be available in the Rust module and will be invoked as console.log in JavaScript.