/// <reference types="react" />
import { Tuple } from 'ts-essentials';
export declare const tuple: <T extends Tuple<any>>(t: T) => T;
export declare type Writeable<T> = {
    -readonly [P in keyof T]: T[P];
};
export declare const isRefObject: <T extends Record<string, never>>(obj: import("react").Ref<T>) => obj is import("react").RefObject<T>;
export declare type FlowReturn<TNext, TReturn = void> = Generator<Promise<TNext>, TReturn, TNext>;