es2015 Enhanced Objects Example

es2015-enhanced-objects-examples.js

var name = "juanma";
var handler = () => `handling things for ${this.name}...`;

var theProtoObj = {
    location: "barcelona",
    toString() {
        return `I'm super!!`
    }
}

var obj = {
    // __proto__
    __proto__: theProtoObj,
    // Shorthand for ‘name: name’ & ‘handler: handler’
    name, handler,
    // Methods
    toString() {
     // Super calls
     return "everyone says " + super.toString();
    },
    // Computed (dynamic) property names
    [ 'prop_' + (() => 42)() ]: 42
};

obj.toString() // "everyone says I'm super!!"
obj.prop_42 // 42
obj.handler(); // "handling things for juanma..."
obj.name; // "juanma"
obj.location; // "barcelona"

//----------------------------

var messages = {
  get latest () {
    if (this.log.length == 0) return;
    return this.log[this.log.length - 1]
  },
  set current (str) {
    this.log[this.log.length] = str;
  },
  log: []
}

messages.current = "hey!";
messages.latest // hey!
messages.current = "you!";
messages.latest // you!
messages.log // ['hey!','you!']