export declare abstract class Controller {
    private static requestHandler;
    static setRequestHandler(fetcher: RequestHandler): Promise<void>;
    static request<T>(url: string, json: boolean | undefined, method: "GET" | "POST" | undefined, headers: RequestInit["headers"], body?: RequestInit["body"]): Promise<T>;
}
export type RequestHandler<T = unknown> = (url: string, json?: boolean, method?: "GET" | "POST", headers?: RequestInit["headers"], body?: RequestInit["body"]) => T | Promise<T>;