/**
 * Hook that returns the width of an element in three stages:
 *  - initialized with 0
 *  - immediately set to element's initial width as soon as it's mounted
 *  - update to new width every time it changes (using `useResizeObserver` hook)
 *
 * @private
 * @param watchResizes If false, ResizeObserver will not be connected and only the initial width will be returned
 * @returns [ref to attach to the element, stateful width of the element]
 *
 * @example
 * const [ref, width] = useContainerWidth();
 * ... // do something with width
 * return <div ref={ref}>...</div>;
 */
export declare const useContainerWidth: <T extends HTMLElement>(watchResizes?: boolean) => readonly [(instance: HTMLElement | null | undefined) => void, number];