Function use_async 

pub fn use_async<T, L>() -> UseAsyncHandle<T, L>
where
    T: Clone + PartialEq + 'static,
    L: Clone + PartialEq + HasLoadingHint + 'static,

Obtains the UseAsyncHandle registered against the current hook context slot.

Behaves like HookContext::use_hook: the same handle (and therefore the same state signal) is returned on every render at the same hook index, so state written by set_state / refetch survives re-renders. Without the hook context (e.g. when called outside a render cycle) the factory falls back to a stand-alone handle — see UseAsyncHandle::new_for_fallback.

The returned handle is Copy, cheap to pass around, and exposes state() / set_state() for non-async testing as well as refetch() for the real wasm path. Render code subscribes to state changes by reading state() inside a render closure.

Returns

• UseAsyncHandle<T, L> - The async handle in the Loading initial state, ready for an refetch(...) from the call site.