interface IdleRequestOptions {
  timeout?: number;
}

interface IdleDeadline {
  readonly didTimeout: boolean;
  timeRemaining(): number;
}

type IdleRequestCallback = ( deadline: IdleDeadline ) => void;

declare function requestIdleCallback(
  callback: IdleRequestCallback,
  options?: IdleRequestOptions
): number;

declare function cancelIdleCallback( handle: number ): void;

declare const __DEV__: boolean;
