import { DisposableStore } from '../lifecycle';
/**
 * A function that is called when an event is emitted.
 */
export type EventListener<T> = (data: T) => any;
/**
 * A function that can be called to remove a previously attached event listener.
 */
export type EventUnsubscribe = () => void;
export interface EventUnsubscribeStore {
    /**
     * Add an event unsubscribe handler
     * @param unsub
     */
    add(unsub: EventUnsubscribe): void;
    /**
     * Call all event unsubscribes and clear store
     */
    clear(): void;
}
/**
 * A function that can be called to attach an event listener.
 *
 * Listeners are called in the order they are attached.
 */
export type Event<T> = (listener: EventListener<T>, thisArgs?: any, store?: EventUnsubscribe[] | EventUnsubscribeStore | DisposableStore) => EventUnsubscribe;
export declare namespace Event {
    const None: Event<any>;
    /**
     * Given an event, returns another event which only fires once.
     */
    function once<T>(event: Event<T>): Event<T>;
    function debouncedListener<T, O = T>(event: Event<T>, listener: (data: O) => any, merge: (last: O | undefined, event: T) => O, delay?: number, leading?: boolean): EventUnsubscribe;
    /**
     * Given an event, returns the same event but typed as `Event<void>`.
     */
    function signal<T>(event: Event<T>): Event<void>;
    function toPromise<T>(event: Event<T>): Promise<T>;
    function runAndSubscribe<T>(event: Event<T>, handler: (e: T | undefined) => any): EventUnsubscribe;
    interface NodeEventEmitter {
        on(event: string | symbol, listener: Function): unknown;
        removeListener(event: string | symbol, listener: Function): unknown;
    }
    function fromNodeEventEmitter<T>(emitter: NodeEventEmitter, eventName: string, map?: (...args: any[]) => T): Event<T>;
    interface DOMEventEmitter {
        addEventListener(event: string | symbol, listener: Function): void;
        removeEventListener(event: string | symbol, listener: Function): void;
    }
    function fromDOMEventEmitter<T>(emitter: DOMEventEmitter, eventName: string, map?: (...args: any[]) => T): Event<T>;
}