anchor.diff:  
   module private Impl =
   
  -  open System
  +  open System.Diagnostics
   
     let assertParams prms =
       if prms.MinSuccessfulTests <= 0 then
  
positive.code:         finally
            stop := true
  
      let timedRes = { r with Time = DateTime.UtcNow.Ticks - start }
      prms.Callback.OnTestResult("", timedRes)
      timedRes
  
  
negative.code:         else
            { Status = Exhausted; Succeeded = s1 + s2; Discarded = d1 + d2; FreqMap = FreqMap.append fm1 fm2; Time = 0L }
  
      let watch = Stopwatch.StartNew()
  
      let r =
        if prms.Workers < 2 then workerFun 0
  