let i = 0;
const key = () => `k${i++}`;
const obj = {
  [key()]: i,
  [key()]: i,
  [key()]: i,
};
console.log(Object.keys(obj).join(','), obj.k0, obj.k1, obj.k2);

const a = 5 & 3;
const b = 5 | 2;
const c = ~5;
const d = 1 << 31;
const e = -1 >>> 28;
const f = 5 ^ 5;
console.log(a, b, c, d, e, f);

'use strict';

function getValue() {
  return this.value;
}

const obj = { value: 42, getValue };
const fn = obj.getValue;

try {
  fn();
} catch (err) {
  console.log(err.constructor.name, typeof this);
}