anchor.diff:          Files : WiXFile seq
           Components : WiXDirectoryComponent seq
       }
  -    override d.ToString() = sprintf "<Direcotry Id=\"%s\" Name=\"%s\>%s%s</Directory>"
  +    override d.ToString() = sprintf "<Directory Id=\"%s\" Name=\"%s\">%s%s</Directory>"
                                   d.Id 
                                   d.Name 
                                   (Seq.fold(fun acc elem -> acc + elem.ToString()) "" d.Files) 
  
positive.code:     if parameters.Id = "" then 
          failwith "No parameter passed for directory Id!"
      parameters
  
  /// Creates WiX component with directories and files from the given DirectoryInfo
  /// The function will create one component for each file [best practice](https://support.microsoft.com/de-de/kb/290997/en-us)
  
negative.code:         failwith "No parameter passed for component ref Id!"
      Some(parameters)
  
  
  type WiXDirectoryComponent = 
      | C of WiXComponent
      | D of WiXDir      
      member w.ToComponentRef() = 
          match w with
          | C c -> c.ToComponentRef()
          | D d -> None  
      override w.ToString() =
            match w with
              | C c -> c.ToString()
  