anchor.diff:                      let mutable pos = 0L
   
                       let length = try Some httpResponseStream.Length with :? System.NotSupportedException -> None
  -                    let! tok = Async.CancellationToken
                       while !bytesRead <> 0 do
                           if printProgress && lastSpeedMeasure.Elapsed > TimeSpan.FromSeconds(10.) then
                               // report speed and progress
  
positive.code: open Paket.NuGetCache
  open Paket.PackageResolver
  open System.Net.Http
  
  type NuGetContent =
      | NuGetDirectory of name:string * contents:NuGetContent list
  
negative.code:                     let mutable readSinceLastMeasure = 0L
  
                      let requestMsg = new HttpRequestMessage(HttpMethod.Get, downloadUri)
                      let! responseMsg = client.SendAsync(requestMsg, HttpCompletionOption.ResponseHeadersRead, t.Token) |> Async.AwaitTask
                      match responseMsg.StatusCode with
                      | HttpStatusCode.OK -> ()
                      | statusCode -> failwithf "HTTP status code was %d - %O" (int statusCode) statusCode
  
                      let! httpResponseStream = responseMsg.Content.ReadAsStreamAsync() |> Async.AwaitTask
                      httpResponseStream.ReadTimeout <- Timeout.Infinite;
  
                      let bufferSize = 1024 * 10
                      let buffer : byte [] = Array.zeroCreate bufferSize
  