import React , { useContext , createContext } from 'react' ; import { RefTracker } from '../hooks' ; const Context = createContext ( { } as RefTracker ) ; /**
 * Access parent ref tracker.
 */ export function useRefTrackerContext ( ) { return useContext ( Context ) ; } export interface RefTrackerProviderProps { refTracker : RefTracker ; } export const RefTrackerProvider = props => { return ( < Context . Provider value = { props . refTracker } > { props . children } < /Context.Provider>); } ;