anchor.diff:    let fsiConfig = FsiEvaluationSession.GetDefaultConfiguration(new InteractiveSettings())
     let argv = Array.append [|"C:\\test.exe"; "--quiet"; "--noninteractive"|] (defaultArg options [||])
     let fsiSession = FsiEvaluationSession(fsiConfig, argv, inStream, outStream, errStream)
  +  let evalFailed = new Event<_>()
   
     /// Registered transformations for pretty printing values
     /// (the default formats value as a string and emits single CodeBlock)
  
positive.code:     ItValue : (obj * Type) option
      Result : (obj * Type) option }
  
  /// A wrapper for F# interactive serivice that is used to evaluate inline snippets
  type FsiEvaluator(?options:string[]) =
    // Initialize F# Interactive evaluation session
  
negative.code:       finally
          Console.SetOut(prev)
      with e ->
        evalFailed.Trigger({ File=file; AsExpression=asExpression; Text=text; Exception=e })
        { Output = None; Result = None; ItValue = None }
  
      /// This event is fired whenever an evaluation of an expression fails
      member x.EvaluationFailed = evalFailed.Publish