/**
 * A logger that takes in the JSON-RPC method and response time in milliseconds.
 */
declare type logger = (methodName: string, duration: number) => unknown;
export declare let logger: logger | null;
/**
 * Set the logger for logging the response time of JSON-RPC requests.
 * @param l the logger to use
 */
export declare const setLogger: (l: logger) => void;
export {};