anchor.diff:    static member AsOption str =
       if String.IsNullOrWhiteSpace str then None else Some str
   
  -  /// Parse date time using either MS JSON format or using ISO 8601
  -  /// that is, either "Date(<msec-since-1/1/1970>)" or something
  +  /// Parse date time using either the JSON milliseconds format or using ISO 8601
  +  /// that is, either "\/Date(<msec-since-1/1/1970>)\/" or something
     /// along the lines of "2013-01-28T00:37Z"
     static member AsDateTime culture (text:string) =
       // Try parse "Date(<msec>)" style format
  
positive.code:     match opt with 
      | Some v -> Nullable v
      | _ -> Nullable()
      
negative.code: #else
      RegexOptions.Compiled
  #endif
    // note on the regex we have /Date()/ and not \/Date()\/ because the \/ escaping 
    // is already taken care of before AsDateTime is called
    let msDateRegex = lazy (new Regex(@"^/Date\((-?\d+)(?:-\d+)?\)/$", regexOptions))
  
  type Operations = 
  