/**
 *  Author: Kevin Nielsen <knielsen@alertlogic.com>
 *  Copyright Alert Logic Inc, 2019
 */
/**
 * @public
 *
 *  AlStopwatch is an attempt to encapsulate a few basic timer-related use cases into a simple interface.
 *  Most uses cases can be handled by one of the three static methods:
 *    `Stopwatch.later` - creates a Stopwatch instance that won't be executed until someone calls its `now` or `again` methods.
 *    `Stopwatch.once` - creates a Stopwatch instance that executes once after a specified delay, defaulting to 0.
 *    `Stopwatch.repeatedly` - creates a Stopwatch instance that executes repeatedly at a given interval until its `cancel` method is called.
 */
export declare class AlStopwatch {
    callback: {
        (): void;
    };
    timer: any;
    interval: number;
    constructor(callback: {
        (): void;
    });
    /**
     *  A static method to generate an unscheduled timer
     */
    static later(callback: {
        (): void;
    }): AlStopwatch;
    /**
     *  A static method to generate a timer that will execute once after a given number of milliseconds.
     */
    static once(callback: {
        (): void;
    }, delay?: number): AlStopwatch;
    /**
     *  A static method to generate a timer that will execute intermittently.
     *  Note that this implementation deviates from the behavior of setInterval by *defaulting*
     *  to firing the timer immediately.
     */
    static repeatedly(callback: {
        (): void;
    }, interval?: number, beginImmediately?: boolean): AlStopwatch;
    static promise(interval: number): Promise<void>;
    /**
     *  The timer's tick handler; executes the callback and, for single-fire timers, clears the timer handle.
     */
    tick: () => void;
    /**
     *  Cancels a scheduled execution.
     */
    cancel: () => void;
    /**
     *  Schedules a repeated execution.  This method has no effect if there is already a scheduled execution.
     */
    again: (delay?: number) => void;
    /**
     * Schedules a repeated execution.  This method will cancel any previously scheduled execution.
     */
    reschedule: (delay?: number) => void;
    /**
     *  Executes the timer immediately (literally, right now!)
     */
    now: () => void;
}