dispatch

import mlreportgen.ppt.*;
pre = Presentation("myPresentation.pptx");
     
dispatcher = MessageDispatcher.getTheDispatcher;
l = addlistener(dispatcher,"Message", ...
      @(src, evtdata) disp(evtdata.Message.formatAsText));
     
dispatch(dispatcher,ErrorMessage("invalid slide",pre));
open(pre);
     
titleText = Text("This is a Title");
titleText.Style = {Bold};

replace(pre,"Title",titleText);
     
close(pre);
     
delete(l);