/**
 * Hook to run a function once after component has been mounted.
 */
export declare function useOnMount(fn: () => void): void;
/**
 * Hook to run a function once after component has been unmounted.
 */
export declare function useOnUnmount(fn: () => void): void;
/**
 * Hook to run a function when a DOM element is resized.
 * See {@link observeResize} for more details.
 *
 * @param fn - receives a DOMRect containing the dimensions of the DOM element.
 * @param opts - extra options, currently supporting a `debounce` specified in ms.
 * @returns callback ref to be placed on target component
 */
export declare function useOnResize(fn: (rect: DOMRect) => any, opts?: {
    debounce?: number;
}): (node: any) => void;
/**
 * Hook to run a function when a DOM element becomes visible / invisible.
 *
 * @see observeVisibleChange() for more details.
 *
 * @param fn - receives a boolean signifying if visible.
 * @returns callback ref to be placed on target component
 */
export declare function useOnVisibleChange(fn: (visible: boolean) => any): (node: any) => void;
/**
 * Hook to run a function when a DOM element scrolls.
 *
 * @param fn - receives the scroll event.
 * @returns callback ref to be placed on target component
 */
export declare function useOnScroll(fn: (ev: Event) => any): (node: any) => void;
/**
 * Hook to return a cached version of a value - similar useCallback() and useMemo().
 * Useful for providing stable object references across renders.
 *
 * @param value - value (typically an object) to be cached and potentially returned to this and
 *      subsequent calls.
 * @param equalsFn - A function taking the previously cached value and the currently presented
 *      value. If evaluates to true, the cached value will be returned rather than the presented
 *      value. If null, any cached value will always be returned.
 */
export declare function useCached<T>(value: T, equalsFn: (prev: T, curr: T) => boolean): T;