/**
 * 取值
 *
 * ```ts
 * import { memoryStorage } from 'sunny-js'
 * memoryStorage.setItem('key', 'value')
 * console.log(memoryStorage.getItem('key'))
 * // => 'value'
 * ```
 *
 */
export declare function getItem<T = any>(key: string | number): T;
/**
 * 存值
 *
 * ```ts
 * import { memoryStorage } from 'sunny-js'
 * memoryStorage.setItem('key', 'value')
 * ```
 *
 */
export declare function setItem(key: string | number, value: unknown): void;
/**
 * 删值
 *
 * ```ts
 * import { memoryStorage } from 'sunny-js'
 * memoryStorage.removeItem('key')
 * ```
 *
 */
export declare function removeItem(key: string | number): boolean;