private void NestedInputHandler_Added(ITextAreaInputHandler handler)
 {
     if (handler == null)
         throw new ArgumentNullException(nameof(handler));
     if (handler.TextArea != TextArea)
         throw new ArgumentException("The nested handler must be working for the same text area!");
     if (IsAttached)
         handler.Attach();
 }
 void NestedInputHandler_Added(ITextAreaInputHandler handler)
 {
     if (handler == null)
     {
         throw new ArgumentNullException("handler");
     }
     if (handler.TextArea != textArea)
     {
         throw new ArgumentException("The nested handler must be working for the same text area!");
     }
     if (isAttached)
     {
         handler.Attach();
     }
 }
		void NestedInputHandler_Added(ITextAreaInputHandler handler)
		{
			if (handler == null)
				throw new ArgumentNullException("handler");
			if (handler.TextArea != textArea)
				throw new ArgumentException("The nested handler must be working for the same text area!");
			if (isAttached)
				handler.Attach();
		}