/// <reference types="react" />
/// <reference types="resize-observer-browser" />
/**
 * Tracks size of an element.
 *
 * ⚗️ _The underlying technology is experimental. Please be aware about browser compatibility before using this in production._
 *
 * @param ref Attribute attached to the element under observation.
 * @param {TypeOf<ResizeObserver>} ResizeObserverOverride Replacement for `window.ResizeObserver`, e.g. [a polyfill](https://github.com/juggle/resize-observer).
 *
 * @returns Dimensions `[width, height]`, falling back to `[0, 0]` when unavailable.
 *
 * @example
 * function Component() {
 *   const ref = useRef<HTMLElement>(null);
 *   const [width, height] = useSize(ref);
 *   // ...
 *   return <ElementToObserve ref={ref} />;
 * }
 */
export default function useSize(ref: React.RefObject<HTMLElement>, ResizeObserverOverride?: typeof ResizeObserver): Readonly<[number, number]>;