pub fn start_main_executor()Expand description
Starts the synthetic “main thread” executor on the current thread.
Platforms that rely on the polyfill do not have an OS-provided main thread,
so we create one by running this function on a thread of your choice. It
blocks forever, driving tasks spawned via [crate::spawn_main] and
[crate::spawn_local]. Most applications spawn a dedicated thread for this
purpose when running on an unsupported target.
§Panics
Panics if the main executor has already been started.