export interface Time {
    datetime: string;
    utc: string;
    local: string;
    by?: string;
    title?: string;
}
export interface Valid {
    interval?: string;
    utc?: string;
    local?: string;
    min?: string | Time | false;
    max?: string | Time | false;
}
export interface Interval {
    start?: Date;
    end?: Date;
}
export declare function validToInterval(valid: Valid): Interval;
export declare function intervalIsValid(interval: Interval, now?: Date): boolean | undefined;
export declare function isValid(valid: Valid, now?: Date): boolean | undefined;
export declare function isInterval(x: any): x is Interval;
export declare function intervalString(interval: Interval): string;
export declare function interval(from: number | null, to: number | null, now?: Date): Interval;