import "./_dnt.polyfills.js";
import type { PromiseMaybe } from "./promise.js";
/**
 * 一个极简的 Least Recently Used 缓存
 * @example
 * ```ts
 * const lrc = new Lrc()
 * function getTime() {
 *      lrc.getOrPut('time', ()=>{
 *           return Date.now()
 *      })
 * }
 * const time1 = getTime()
 * // hit cache
 * const time2 = getTime()
 * time1 === time2
 *
 * // remove all cache
 * lrc.clear(0)
 *
 * const time3 = getTime()
 * time1 !== time3
 * ```
 */
export declare class Lrc<K, V> {
    #private;
    cacheSize: number;
    clearThreshold: number;
    constructor(cacheSize?: number, clearThreshold?: number);
    /**
     * 读取缓存，否则创建
     */
    getOrPut(key: K, getValue: () => V): V;
    /**
     * 读取缓存，否则异步创建。
     * 异步创建过程中会加锁，不会同时执行
     */
    getOrPutAsync(key: K, getValue: () => PromiseMaybe<Awaited<V>>): Promise<Awaited<V>>;
    /**
     * 写入缓存
     */
    set(key: K, value: V): this;
    /**
     * 删除缓存
     */
    delete(key: K): boolean;
    /**
     * 判断是否存在缓存
     */
    has(key: K): boolean;
    /**
     * 尝试清理缓存，如果到达清理阈值的话
     */
    tryClear(): void;
    /**
     * 清理缓存
     * @param keepSize 要保留的缓存数量
     */
    clear(keepSize?: number): void;
}
//# sourceMappingURL=lrc.d.ts.map