arrakis/modules/console/src/EventEmitter.js

Helpfull development framework

module.exports = class EventEmitter{
	constructor(){
		this._events = {};
		this._eventsCount = 0;
	}

	on(event, listener, caller=this){
		if(this._events.newListener != null)
			this.emit('newListener', event, listener);

		this._events[event] = {
			listener: listener,
			caller: caller
		}

		this._eventsCount++;
	}

	append(event, listener, caller=this, target=this){
		event = target.constructor.name+'_'+event;

		this.on(event, listener, caller);

		target[event] = () => {
			this.emit(event);
		};
	}

	emit(event){
		var event, args;

		event = this._events[event];

		if(event == null)
			throw new Error('No listener can be emitted with that name ['+event+'}');

		args = [];
		for(var key in arguments)
			args.push(arguments);

		args.shift();

		return event.listener.apply(event.caller, args);
	}

}