vue/types/v3-define-async-component.d.ts

import { AsyncComponent, Component } from './options'

export type AsyncComponentResolveResult<T = Component> = T | { default: T } // es modules

export type AsyncComponentLoader<T = any> = () => Promise<
  AsyncComponentResolveResult<T>
>

export interface AsyncComponentOptions {
  loader: AsyncComponentLoader
  loadingComponent?: Component
  errorComponent?: Component
  delay?: number
  timeout?: number
  // suspensible?: boolean
  onError?: (
    error: Error,
    retry: () => void,
    fail: () => void,
    attempts: number
  ) => any
}

export function defineAsyncComponent(
  source: AsyncComponentLoader | AsyncComponentOptions
): AsyncComponent