react-native-vision-camera/lib/hooks/internal/useStableCallback.js

VisionCamera is the fastest and most powerful Camera for react-native.

import { useCallback, useRef } from 'react';
/**
 * Returns a wrapper with a stable identity that always calls the latest
 * {@linkcode callback}. Re-renders that change only the {@linkcode callback}
 * reference do not change the returned identity.
 *
 * When {@linkcode callback} is `undefined` or `null`, the hook returns
 * that same nullish value. The returned identity therefore only changes
 * when {@linkcode callback} flips between "defined" and "nullish" — not
 * when the function itself changes — which makes it safe as a
 * `useEffect`/`useLayoutEffect` dependency.
 */
export function useStableCallback(callback) {
    const callbackRef = useRef(callback);
    callbackRef.current = callback;
    const stable = useCallback((...args) => {
        const fn = callbackRef.current;
        if (typeof fn !== 'function') {
            throw new Error('useStableCallback: wrapped callback was invoked but the underlying callback is not a function. ' +
                'The hook returns the nullish value directly when the input is null/undefined, so callers ' +
                'should not hold a reference to the wrapper in that state.');
        }
        return fn(...args);
    }, []);
    if (callback == null)
        return callback;
    return stable;
}