or es2015 - whatever you want to call it
Sample code
let storeEvents = EventEmitter();
let store = {
value: 0
}
storeEvents.mixin(store);
function increaseValue() {
this.value += 1;
}
store.bind('tick', increaseValue);
console.log(store.value); // 0
store.trigger('tick');
console.log(store.value); // 1
store.unbind('tick', increaseValue);
store.trigger('tick');
console.log(store.value); // 1