export interface IVisitLog {
    add(url: string): void;
    has(url: string): boolean;
    siteCount(url: string): number | undefined;
}
export declare class VisitLog implements IVisitLog {
    private readonly visited;
    private readonly counts;
    add(url: string): void;
    readonly has: (url: string) => boolean;
    readonly siteCount: (url: string) => number | undefined;
}