import { FetchResult } from './typings';
export interface CacheLayer<K, V> {
    get(key: K, fetcher?: () => Promise<FetchResult<V>>): Promise<V | void> | V | void;
    has(key: K): Promise<boolean> | boolean;
    set(key: K, value: V, maxAge?: number | void): Promise<boolean> | boolean;
    getStats?(name?: string): any;
}