/**
 * 接收 fn ，返回一个和 fn 签名一致的函数 fn'。当已经有一个 fn' 在运行时，再调用
 * fn' 会直接返回运行中 fn' 的 Promise，直到 Promise 结束 pending 状态
 */
export declare function singleton<Fn extends (...args: any) => Promise<any>>(fn: Fn): Fn;
export declare function ensureFolderExist(fileOrFolderPath: string): void;
export declare function assert(assertion: unknown, msg?: string): asserts assertion;
export declare function assertStringType(data: unknown, msg?: string): asserts data is string;
export declare function assertNumberType(data: unknown, msg?: string): asserts data is number;
export declare function assertObjectType(data: unknown, msg?: string): asserts data is object;
export declare function get__ac_signature(one_time_stamp: any, one_site: any, one_nonce: any, ua_n: any): string;