anchor.diff:  
               if aI.IsRest then yield " ..."
   
  -            if not aI.Mandatory then yield "]"
  -            if aI.Id <> (Seq.last sorted).Id then yield " "
  +            if not aI.Mandatory then yield ']'
  +            if aI.Id <> (Seq.last sorted).Id then yield ' '
       } |> String.build
   
   /// <summary>
  
positive.code:             if not aI.Hidden then
                  yield! printArgUsage aI
  
          if not <| first.IsEmpty then yield '\n'
  
          for aI in last do 
              if not aI.Hidden then
  
negative.code: 
              yield ": "
              yield aI.Usage
              yield Environment.NewLine
      }
  
  /// <summary>
  