EvalException: Oops! A null expression has been found. A not null statement was expected.. The error occurred for expression "d" at position 0 near "d".
--OriginalCode: d
--ParsedCode: d
--Token: d
--StartPosition: 0
--NearText: d
StackTrace:
   在 .(ExpressionScope , SyntaxNode , Expression , Boolean )
   在 Z.Expressions.CodeCompiler.CSharp.ExpressionParser.ParseSyntax(ExpressionScope scope, SyntaxNode node, Type resultType)
   在 .[](EvalContext , String , IDictionary`2 , Type , EvalCompilerParameterKind , ExpressionScope , String , Boolean , Boolean )
   在 .[](EvalContext , String , IDictionary`2 , Type , EvalCompilerParameterKind , Boolean , Boolean , Boolean )
   在 Z.Expressions.EvalContext.Execute[TResult](String code)
   在 DynamicClass.<OnWindowCreated>b__0(Object sender, EventArgs args)
   在 System.EventHandler.Invoke(Object sender, EventArgs e)
   在 ICSharpCode.AvalonEdit.TextEditor.OnTextChanged(EventArgs e)
   在 ICSharpCode.AvalonEdit.TextEditor.ReceiveWeakEvent(Type managerType, Object sender, EventArgs e)
   在 ICSharpCode.AvalonEdit.TextEditor.System.Windows.IWeakEventListener.ReceiveWeakEvent(Type managerType, Object sender, EventArgs e)
   在 System.Windows.WeakEventManager.ListenerList.DeliverEvent(Listener& listener, Object sender, EventArgs args, Type managerType)
   在 System.Windows.WeakEventManager.ListenerList.DeliverEvent(Object sender, EventArgs args, Type managerType)
   在 System.Windows.WeakEventManager.DeliverEvent(Object sender, EventArgs args)
   在 ICSharpCode.AvalonEdit.Document.TextDocument.FireChangeEvents()
   在 ICSharpCode.AvalonEdit.Document.TextDocument.EndUpdate()
   在 ICSharpCode.AvalonEdit.Document.TextDocument.Replace(Int32 offset, Int32 length, ITextSource text, OffsetChangeMap offsetChangeMap)
   在 ICSharpCode.AvalonEdit.Document.TextDocument.Insert(Int32 offset, String text)
   在 ICSharpCode.AvalonEdit.Editing.EmptySelection.ReplaceSelectionWithText(String newText)
   在 ICSharpCode.AvalonEdit.Editing.TextArea.ReplaceSelectionWithText(String newText)
   在 ICSharpCode.AvalonEdit.Editing.TextArea.PerformTextInput(TextCompositionEventArgs e)
   在 ICSharpCode.AvalonEdit.Editing.TextArea.OnTextInput(TextCompositionEventArgs e)
   在 System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   在 System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   在 System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   在 System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   在 System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args)
   在 System.Windows.Input.InputManager.ProcessStagingArea()
   在 System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   在 System.Windows.Input.TextCompositionManager.PostProcessInput(Object sender, ProcessInputEventArgs e)
   在 System.Windows.Input.InputManager.RaiseProcessInputEventHandlers(ProcessInputEventHandler postProcessInput, ProcessInputEventArgs processInputEventArgs)
   在 System.Windows.Input.InputManager.ProcessStagingArea()
   在 System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   在 System.Windows.Input.TextCompositionManager.PostProcessInput(Object sender, ProcessInputEventArgs e)
   在 System.Windows.Input.InputManager.RaiseProcessInputEventHandlers(ProcessInputEventHandler postProcessInput, ProcessInputEventArgs processInputEventArgs)
   在 System.Windows.Input.InputManager.ProcessStagingArea()
   在 System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   在 System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
   在 System.Windows.Interop.HwndKeyboardInputProvider.ProcessTextInputAction(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   在 System.Windows.Interop.HwndSource.OnPreprocessMessage(Object param)
   在 System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   在 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)