Function sample

src/commands/serve.rs:1065–1075

(
        mut store: StoreContextMut<Host>,
        f: impl FnOnce(&mut GuestProfiler, StoreContext<Host>),
    )

    )?));

    fn sample(
        mut store: StoreContextMut<Host>,
        f: impl FnOnce(&mut GuestProfiler, StoreContext<Host>),
    ) {
        let mut profiler = store.data_mut().guest_profiler.take().unwrap();
        f(
            Arc::get_mut(&mut profiler).expect("profiling doesn't support threads yet"),
            store.as_context(),
        );
        store.data_mut().guest_profiler = Some(profiler);
    }

    // Hostcall entry/exit, etc.
    store.call_hook(|store, kind| {