export declare class CrontabExpression {
    protected _second: string;
    protected _minute: string;
    protected _hour: string;
    protected _dayOfMonth: string;
    protected _month: string;
    protected _dayOfWeek: string;
    protected _alias?: CrontabExpression.Alias;
    command: string;
    constructor(params: CrontabExpression.Params);
    get alias(): CrontabExpression.Alias | undefined;
    set alias(alias: CrontabExpression.Alias);
    get second(): string;
    set second(second: string);
    get minute(): string;
    set minute(minute: string);
    get hour(): string;
    set hour(hour: string);
    get dayOfMonth(): string;
    set dayOfMonth(dayOfMonth: string);
    get month(): string;
    set month(month: string);
    get dayOfWeek(): string;
    set dayOfWeek(dayOfWeek: string);
    protected resetAlias(): void;
    toString(format?: "standard" | "extended"): string;
    protected static parseExpression(expression: string, type?: CrontabExpression.Type): CrontabExpression.Params;
    static parse(expression: string, type?: CrontabExpression.Type): CrontabExpression;
}
export declare namespace CrontabExpression {
    type Type = "standard" | "extended";
    const Aliases: {
        yearly: string;
        annually: string;
        monthly: string;
        weekly: string;
        daily: string;
        hourly: string;
        minutely: string;
        secondly: string;
        weekdays: string;
        weekends: string;
    };
    type Alias = keyof typeof Aliases;
    type Params = {
        second: string;
        minute: string;
        hour: string;
        dayOfMonth: string;
        month: string;
        dayOfWeek: string;
        alias?: Alias;
        command: string;
    };
}