import { type IScheduler, type ISink, type IStream } from '../../stream/index.js';
export interface IStateCurry {
    (initialState?: undefined): <T>(source: IStream<T>) => IStream<T>;
    <I extends NonNullable<unknown> | null, T>(initialState: I, source: IStream<T>): IStream<T | I>;
    <I>(initialState: I): <T>(source: IStream<T>) => IStream<T | I>;
}
/**
 * Create a multicast stream that remembers its latest value
 *
 * Without initialState (undefined):
 * stream:        -1-2-3--->
 * subscriber1:   -1-2-3--->
 * subscriber2:      2-3--->
 *
 * With initialState (0):
 * stream:        -1-2-3--->
 * subscriber1:   01-2-3--->
 * subscriber2:    1-2-3--->
 */
export declare const state: IStateCurry;
export declare class State<A> implements IStream<A> {
    readonly source: IStream<A>;
    readonly initialState?: A | undefined;
    latestValue?: {
        value: A;
    };
    constructor(source: IStream<A>, initialState?: A | undefined);
    run(sink: ISink<A>, scheduler: IScheduler): Disposable;
}