export declare class Instant {
    readonly year: number;
    readonly month: number;
    readonly day: number;
    constructor(year: number, month?: number, day?: number);
    get date(): Date;
    static fromString(value: string): Instant;
    offset(offset: "first-of" | "last-of" | number, unit: PeriodUnit): Instant;
    period(unit: PeriodUnit, size?: number): Period;
    toString(): string;
}
export declare class Period {
    readonly unit: PeriodUnit;
    readonly start: Instant;
    readonly size: number;
    constructor(unit: PeriodUnit, start: Instant, size?: number);
    get days(): number;
    get first_day(): Period;
    get first_month(): Period;
    static fromString(value: string): Period;
    get last_3_months(): Period;
    get last_month(): Period;
    get last_year(): Period;
    get n_2(): Period;
    offset(offset: "first-of" | "last-of" | number, unit?: PeriodUnit): Period;
    get stop(): Instant;
    get this_year(): Period;
    toString(): string;
}
export type PeriodUnit = "day" | "eternity" | "month" | "year";
export declare const dateRegExp: RegExp;
export declare const instantRegExp: RegExp;
export declare function sortValueByInstantDescending<T>(valueByInstant: {
    [instant: string]: T;
}): [string, T][];