const obj = {
  foo() {
    return "bar";
  },
};

console.log(obj.foo());
// Expected output: "bar"

var obj = {
  foo: function () {
    /* code */
  },
  bar: function () {
    /* code */
  },
};

var obj = {
  foo() {
    /* code */
  },
  bar() {
    /* code */
  },
};

// ES6 
var obj2 = {
  g: function* () {
    var index = 0;
    while (true) yield index++;
  },
};

// 
var obj2 = {
  *g() {
    var index = 0;
    while (true) yield index++;
  },
};

var it = obj2.g();
console.log(it.next().value); // 0
console.log(it.next().value); // 1

// ES6 
var obj3 = {
  f: async function () {
    await some_promise;
  },
};

// 
var obj3 = {
  async f() {
    await some_promise;
  },
};

var obj4 = {
  f: async function* () {
    yield 1;
    yield 2;
    yield 3;
  },
};

// The same object using shorthand syntax
var obj4 = {
  async *f() {
    yield 1;
    yield 2;
    yield 3;
  },
};

var obj = {
  method() {},
};
new obj.method(); // TypeError: obj.method is not a constructor

var obj = {
  *g() {},
};
new obj.g(); // TypeError: obj.g is not a constructor (changed in ES2016)

var obj = {
  a: "foo",
  b() {
    return this.a;
  },
};
console.log(obj.b()); // "foo"

var bar = {
  foo0: function () {
    return 0;
  },
  foo1() {
    return 1;
  },
  ["foo" + 2]() {
    return 2;
  },
};

console.log(bar.foo0()); // 0
console.log(bar.foo1()); // 1
console.log(bar.foo2()); // 2