export declare class StringDeduplicator {
    private readonly maxSize;
    private readonly expireTime;
    private readonly items;
    constructor(maxSize?: number, expireTime?: number | null);
    checkAndRecord(item: string): boolean;
    has(item: string): boolean;
    clear(): void;
    delete(item: string): boolean;
    size(): number;
    getExpireTime(): number | null;
    getMaxSize(): number;
    private isExpired;
    private cleanup;
}