/**
 * LRU (Least Recently Used) Map implementation
 */
export declare class LRUMap<K = any, V = any> extends Map<K, V> {
    /**
     * the max number of total items
     */
    private _maxSize;
    /**
     * LRU (Least Recently Used) Map implementation
     *
     * will remove the oldest item when reach the size limit
     *
     * @param maxSize maximum cache item number, default is 1024
     * @example
     *
     * ```ts
     * const m = new LRUMap(1)
     * m.set('a','v') // {'a':'v'}
     * m.set('b','c') // {'b':'c'}
     * ```
     */
    constructor(maxSize?: number);
    get(key: K): V | undefined;
    set(key: K, val: V): this;
    private first;
}
export default LRUMap;