/**
 * Like React's [useState](https://reactjs.org/docs/hooks-reference.html#usestate)
 * but it makes sure the component that uses this state hook is mounted before updating state
 * @param {D} initialValue
 * @returns {[D, Dispatch<D>]} an array of 2 items
 * the first is the current state, the second is a function that enables
 * updating the state if the component is not mounted
 *
 * D is the type passed when then useMountedState is used
 * e.g. const [pass, setPass] = useMountedState<string>('someString');
 */
export declare const useMountedState: <D>(initialState: D | (() => D)) => readonly [D, (value: D) => void];