* Can be extended to provide event functionality in other classes.
*
* @class EventEmitter Manages event registering and emitting.
*/
functionEventEmitter(){}
// Shortcuts to improve speed and size
varproto=EventEmitter.prototype;
varexports=this;
varoriginalGlobalValue=exports.EventEmitter;
/**
* Finds the index of the listener for the event in its storage array.
*
* @param {Function[]} listeners Array of listeners to search through.
* @param {Function} listener Method to look for.
* @return {Number} Index of the specified listener, -1 if not found
* @api private
*/
functionindexOfListener(listeners,listener){
vari=listeners.length;
while(i--){
if(listeners[i].listener===listener){
returni;
}
}
return-1;
}
/**
* Alias a method while keeping the context correct, to allow for overwriting of target method.
*
* @param {String} name The name of the target method.
* @return {Function} The aliased method
* @api private
*/
functionalias(name){
returnfunctionaliasClosure(){
returnthis[name].apply(this,arguments);
};
}
/**
* Returns the listener array for the specified event.
* Will initialise the event object and listener arrays if required.
* Will return an object if you use a regex search. The object contains keys for each matched event. So /ba[rz]/ might return an object containing bar and baz. But only if you have either defined them with defineEvent or added some listeners to them.
* Each property in the object response is an array of listener functions.
*
* @param {String|RegExp} evt Name of the event to return the listeners from.
* @return {Function[]|Object} All listener functions for the event.
*/
proto.getListeners=functiongetListeners(evt){
varevents=this._getEvents();
varresponse;
varkey;
// Return a concatenated array of all matching events if
// the selector is a regular expression.
if(evtinstanceofRegExp){
response={};
for(keyinevents){
if(events.hasOwnProperty(key)&&evt.test(key)){
response[key]=events[key];
}
}
}
else{
response=events[evt]||(events[evt]=[]);
}
returnresponse;
};
/**
* Takes a list of listener objects and flattens it into a list of listener functions.
*
* @param {Object[]} listeners Raw listener objects.
* @return {Function[]} Just the listener functions.
* Fetches the requested listeners via getListeners but will always return the results inside an object. This is mainly for internal use but others may find it useful.
*
* @param {String|RegExp} evt Name of the event to return the listeners from.
* @return {Object} All listener functions for an event in an object.
* Defines an event name. This is required if you want to use a regex to add a listener to multiple events at once. If you don't do this then how do you expect it to know what event to add to? Should it just add to every possible match for a regex? No. That is scary and bad.
* You need to tell it what event names should be matched by a regex.
*
* @param {String} evt Name of the event to create.
* @return {Object} Current instance of EventEmitter for chaining.
*/
proto.defineEvent=functiondefineEvent(evt){
this.getListeners(evt);
returnthis;
};
/**
* Uses defineEvent to define multiple events.
*
* @param {String[]} evts An array of event names to define.
* @return {Object} Current instance of EventEmitter for chaining.
*/
proto.defineEvents=functiondefineEvents(evts){
for(vari=0;i<evts.length;i+=1){
this.defineEvent(evts[i]);
}
returnthis;
};
/**
* Removes a listener function from the specified event.
* When passed a regular expression as the event name, it will remove the listener from all events that match it.
*
* @param {String|RegExp} evt Name of the event to remove the listener from.
* @param {Function} listener Method to remove from the event.
* @return {Object} Current instance of EventEmitter for chaining.
* Adds listeners in bulk using the manipulateListeners method.
* If you pass an object as the second argument you can add to multiple events at once. The object should contain key value pairs of events and listeners or listener arrays. You can also pass it an event name and an array of listeners to be added.
* You can also pass it a regular expression to add the array of listeners to all events that match it.
* Yeah, this function does quite a bit. That's probably a bad thing.
*
* @param {String|Object|RegExp} evt An event name if you will pass an array of listeners next. An object if you wish to add to multiple events at once.
* @param {Function[]} [listeners] An optional array of listener functions to add.
* @return {Object} Current instance of EventEmitter for chaining.
* Removes listeners in bulk using the manipulateListeners method.
* If you pass an object as the second argument you can remove from multiple events at once. The object should contain key value pairs of events and listeners or listener arrays.
* You can also pass it an event name and an array of listeners to be removed.
* You can also pass it a regular expression to remove the listeners from all events that match it.
*
* @param {String|Object|RegExp} evt An event name if you will pass an array of listeners next. An object if you wish to remove from multiple events at once.
* @param {Function[]} [listeners] An optional array of listener functions to remove.
* @return {Object} Current instance of EventEmitter for chaining.
* Edits listeners in bulk. The addListeners and removeListeners methods both use this to do their job. You should really use those instead, this is a little lower level.
* The first argument will determine if the listeners are removed (true) or added (false).
* If you pass an object as the second argument you can add/remove from multiple events at once. The object should contain key value pairs of events and listeners or listener arrays.
* You can also pass it an event name and an array of listeners to be added/removed.
* You can also pass it a regular expression to manipulate the listeners of all events that match it.
*
* @param {Boolean} remove True if you want to remove listeners, false if you want to add.
* @param {String|Object|RegExp} evt An event name if you will pass an array of listeners next. An object if you wish to add/remove from multiple events at once.
* @param {Function[]} [listeners] An optional array of listener functions to add/remove.
* @return {Object} Current instance of EventEmitter for chaining.
