const obj = {
  a: 1,
  b: 2,
  getSum() {
    return this.a + this.b;
  }
};

const cloneObj = { ...obj, getSum() { return this.b + this.a; } };

console.log(obj.getSum());
console.log(cloneObj.getSum());

const obj = {
  value: 42,
  getValue() {
    return Math.max(this.value, 50);
  }
};

const obj2 = {
  value: 25,
  getValue: obj.getValue
};

console.log(obj.getValue());
console.log(obj2.getValue());

const obj = {
  count: 0,
  increment() {
    this.count++;
  },
  getCount() {
    return (() => this.count)();
  }
};

obj.increment();
obj.increment();

console.log(obj.getCount());

const obj = {
  data: [1, 2, 3],
  getData() {
    return this.data.map(x => x * 2);
  }
};

const newData = obj.getData.bind({ data: [4, 5, 6] })();
console.log(newData);

const obj = {
  value: 1,
  increment() {
    this.value++;
  }
};

const increment = obj.increment;
increment();

console.log(obj.value);