interface AsyncLoader<T> {
    (key: string): Promise<T>;
}
export interface AsyncCachedLoader<T> extends AsyncLoader<T> {
    getLength: () => number;
    getCount: () => number;
}
interface CacheOptions<T> {
    max?: number;
    maxAge?: number;
    length?: (value: T, key?: string) => number;
}
/**
 * Memoize an async function that takes a single string key.
 * Backed by async-cache.
 */
export default function asyncMemoize<T>(func: AsyncLoader<T>, options?: CacheOptions<T>): AsyncCachedLoader<T>;
export {};