Effects

useDebouncedEffect

Run an effect after a delay, resetting the timer when dependencies change:

useDebouncedEffect(
    () => {
        fetchResults(query);
    },
    [query],
    300,
);

Similar to debouncing state, but for side effects (API calls, layout measurement).

useEffectOnUpdate

Like useEffect, but skips the first mount — runs only on updates:

useEffectOnUpdate(() => {
    saveDraft(formValues);
}, [formValues]);

Use when initialization is handled elsewhere and you only want to react to changes.

useRefresh

Returns [token, refresh] where token is a number that increments on each refresh() call:

const [connectionToken, reconnect] = useRefresh();

React.useEffect(() => {
    const socket = connect();
    return () => socket.close();
}, [connectionToken]);

Handy for reconnect loops without storing boolean toggles.