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use-callback-ref

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import * as React from 'react'; import { assignRef } from './assignRef'; import { useCallbackRef } from './useRef'; var useIsomorphicLayoutEffect = typeof window !== 'undefined' ? React.useLayoutEffect : React.useEffect; var currentValues = new WeakMap(); /** * Merges two or more refs together providing a single interface to set their value * @param {RefObject|Ref} refs * @returns {MutableRefObject} - a new ref, which translates all changes to {refs} * * @see {@link mergeRefs} a version without buit-in memoization * @see https://github.com/theKashey/use-callback-ref#usemergerefs * @example * const Component = React.forwardRef((props, ref) => { * const ownRef = useRef(); * const domRef = useMergeRefs([ref, ownRef]); // 👈 merge together * return <div ref={domRef}>...</div> * } */ export function useMergeRefs(refs, defaultValue) { var callbackRef = useCallbackRef(defaultValue || null, function (newValue) { return refs.forEach(function (ref) { return assignRef(ref, newValue); }); }); // handle refs changes - added or removed useIsomorphicLayoutEffect(function () { var oldValue = currentValues.get(callbackRef); if (oldValue) { var prevRefs_1 = new Set(oldValue); var nextRefs_1 = new Set(refs); var current_1 = callbackRef.current; prevRefs_1.forEach(function (ref) { if (!nextRefs_1.has(ref)) { assignRef(ref, null); } }); nextRefs_1.forEach(function (ref) { if (!prevRefs_1.has(ref)) { assignRef(ref, current_1); } }); } currentValues.set(callbackRef, refs); }, [refs]); return callbackRef; }