Emitter.js

var Emitter = {
    events: [],
    emit(eventName, ...args){
        this.events.forEach(function(event){
            if(event.name == eventName){
                event.cb.apply(null, args)
            }
        })
    },
    on(eventName, cb){
        this.events.push({
            name: eventName,
            cb: cb
        })
    },
    off(eventName){
        var len = this.events.length;
        while(len--){
            if(this.events[len].name === eventName){
                this.events.splice(len, 1);
            }
        }
    }
};


Emitter.on('toggle', function(){
  console.log('toggle', arguments)
})

Emitter.emit('toggle', 'param1', 'param2')