anchor.diff:          editor.InsertAtCaret (nonBreakingSpace + t)
   
       let prompt() =
  -        editor.InsertAtCaret ("\n")
  +        editor.InsertAtCaret ("\n> ")
   
       let setupSession() =
           try
  
positive.code: 
      let setCaretLine (s:string) =
          let line = editor.GetLineByOffset editor.CaretOffset
          editor.ReplaceText(line.Offset, line.EndOffset - line.Offset, s)
  
      member x.Session = session
      member x.Shutdown()  =
  
negative.code:                     let line =
                          x.Editor.CaretLine
                          |> x.Editor.GetLine 
                      let lineStr = (line |> x.Editor.GetLineText)
  
                      if lineStr.TrimStart().StartsWith("> ") then
                          fsi.SendCommand lineStr.[2..]
                      else
                          fsi.SendCommand lineStr
                            
                      x.Editor.CaretOffset <- line.EndOffset
                      x.Editor.InsertAtCaret "\n"
                      if not (lineStr.TrimEnd().EndsWith(";;")) then
                          x.Editor.InsertAtCaret "- "
                  false
              | SpecialKey.Up -> 
                  if x.Editor.CaretLine = x.Editor.LineCount then
  