anchor.diff:  
       member this.Move currentPath newPath =
           let moveFile source dest =
  +            this.PrepForOverwrite <| FileInfo dest
               FileSystem.MoveFile(source, dest, true)
           let rec moveDir source dest =
               if Directory.Exists dest then
  
positive.code:                 |> Seq.iter (fun dir -> getDest dir |> Directory.CreateDirectory |> ignore)
              // copy files
              Directory.GetFiles(source, "*", SearchOption.AllDirectories)
                  |> Seq.iter (fun file -> File.Copy(file, getDest file, true))
          else
              File.Copy(source, dest, true)
  
      member this.Recycle path =
          let wp = wpath path
  
negative.code:     member this.Copy currentPath newPath =
          let source = wpath currentPath
          let dest = wpath newPath
          let copyFile source dest =
              this.PrepForOverwrite <| FileInfo dest
              File.Copy(source, dest, true)
          if Directory.Exists source then
              let getDest sourcePath = Regex.Replace(sourcePath, "^" + (Regex.Escape source), dest)
              // copy folder structure
  