https://www.skjaak.kommune.no/script/eventbus/eventbus.min.js

1var EventBus=function(){function EventBus(){this.listeners={}}return EventBus.prototype.addEventListener=function(type,callback,scope){for(var args=[],numOfArgs=arguments.length,i=0;i<numOfArgs;i++)args.push(arguments[i]);args=args.length>3?args.splice(3,args.length-1):[],void 0!==this.listeners[type]?this.listeners[type].push({scope:scope,callback:callback,args:args}):this.listeners[type]=[{scope:scope,callback:callback,args:args}]},EventBus.prototype.dispatch=function(type,target){for(var event={type:type,target:target},args=[],numOfArgs=arguments.length,i=0;i<numOfArgs;i++)args.push(arguments[i]);if(args=args.length>2?args.splice(2,args.length-1):[],args=[event].concat(args),void 0!==this.listeners[type])for(var listeners=this.listeners[type].slice(),numOfCallbacks=listeners.length,i=0;i<numOfCallbacks;i++){var listener=listeners[i];if(listener&&listener.callback){var concatArgs=args.concat(listener.args);listener.callback.apply(listener.scope,concatArgs)}}},EventBus}();window.eventBus||(window.eventBus=new EventBus);