export declare class LogListHelper {
    static level_1<T>(handler: (p: T) => string, list: T[], prefix?: string, sep?: string): () => string;
    static level_2<T1, T2>(handlerLevel_1: (p: T1) => T2[], handlerLevel_2: (p: T2) => string, list: T1[], prefix?: string): string;
}