在 F# 中，异步由 async 计算构建器表示，它不是 Task 的精确模拟>，但通常可以用来代替一个:

In F#, asynchrony is represented by the async computation builder, which is not an exact analog of Task, but can generally be used in place of one:

member public this.GetFooAsync (content : byte[]) = 
   async {
      use stream = new MemoryStream(content) 
      return! this.bar.GetFooAsync(stream) |> Async.AwaitTask
   } 
   |> Async.StartAsTask