Certain tasks, like creating an AudioContext or RtcPeerConnection, can only be performed on the main browser thread.
wasm_main_executor provides an easy way to send futures to the main browser thread from any context. This allows
web workers to spawn main-threaded tasks and await their completion, and facilitates the implementation of cross-thread
polyfills/shims.
The following is a simple example of executor usage:
async fn test_future() -> i32 {
// Do some async or main-threaded work...
2
}
// Start the executor. This must be called from the main browser thread.
wasm_main_executor::initialize().unwrap();
// Futures may be spawned on background threads using the executor.
// The future runs on the main thread.
let fut = wasm_main_executor::spawn(test_future());
// A future is returned which may be awaited on the background thread.
assert_eq!(2, futures::executor::block_on(fut));