import { GeneralFunction } from "../types";
/**
 * TemporaryUnAvailableError
 *
 * when the circuit breaker is open (failure happened latest), will direct throw this error
 *
 * @internal please do not throw this error outside of newdash inner functions
 */
export declare class TemporaryUnAvailableError extends Error {
    /**
     * the error cause the function temporary not available
     */
    causeError: Error;
    constructor(msg: string, causeError?: Error);
}
/**
 * fallback to circuit
 *
 * will directly raise error [[TemporaryUnAvailableError]] when some error happened before in duration
 *
 * @category Fallback
 * @param runner
 * @param openDuration default is 10000 (10 seconds)
 * @param cacheSize the timer & error cache size, default is 1024
 */
export declare function circuit<T extends GeneralFunction>(runner: T, openDuration?: number, cacheSize?: number): T;