import { ObservableInput } from 'rxjs';
import React, { ComponentType } from 'react';
export declare const NOT_YET_EMITTED: unique symbol;
export type NOT_YET_EMITTED = typeof NOT_YET_EMITTED;
/**
 * React hook to subscribe to a stream
 *
 * Each emit from the stream will make the component re-render with the new
 * value. Initially, `NOT_YET_EMITTED` is returned, because an `Observable`
 * has no guarantee for when the first emit will happen. This initial
 * value may be overridden with the `defaultValue` argument.
 *
 * @param source$ Stream that provides the needed values
 * @param defaultValue Default value returned on init until stream emits new value
 */
export declare const useStream: <T>(source$: ObservableInput<T>, defaultValue?: T | undefined) => typeof NOT_YET_EMITTED | T;
/**
 * Higher order component for connecting a component to a stream
 *
 * The stream does not need to provide all the properties the component expects,
 * any missing properties will be required by the component returned from this
 * component.
 *
 * Typescript does, in certain cases, allow for extra properties to be unpacked
 * on a component. This means it may be possible to send props which would be
 * provided by the stream. In these cases the values from the stream will
 * override any values passed as props.
 *
 * @param Component Component that will recieve props from the stream
 * @param stream$ Stream that will provide props to the component
 * @returns A component that renders the original component with props retrieved
 *  from the stream
 * @see {@link useStream}
 */
export declare const connect: <Props extends object, Observed extends Partial<Props>>(Component: React.ComponentType<Props>, stream$: ObservableInput<Observed>) => (props: Omit<Props, keyof Observed>) => React.ReactElement<Props, string | React.JSXElementConstructor<any>> | null;
/**
 * Higher order component for connecting a component to a stream
 *
 * This is the same as {@link connect }, but takes a factory for the stream. A
 * new stream will be retrieved from the factory for every new mount of the
 * component.
 *
 * @param Component Component that will receive props from the stream
 * @param createInstanceStream Function to create the stream for each instance
 *  of the component
 * @returns A component that renders the original component with props retrieved
 *  from the stream
 * @see {@link connect}
 */
export declare const connectInstance: <Props extends object, Observed extends Partial<Props>>(Component: React.ComponentType<Props>, createInstanceStream: (instance: string) => ObservableInput<Observed>) => (props: Omit<Props, keyof Observed>) => React.ReactElement<Props, string | React.JSXElementConstructor<any>> | null;