JavaScript Objects

object.js

const NAME = Symbol();
const person = {
  [NAME]: 'Flavio'
};

person[NAME]; //'Flavio'

const RUN = Symbol();
person[RUN] = () => 'Person is running';
console.log(person[RUN]()); //'Person is running'

person.surname = 'Copes';

// for...in
for (const prop in person) { console.log(prop) } // surname

console.log(Object.keys(person)); // ["surname"]
console.log(Object.getOwnPropertyNames(person)); // ["surname"]

console.log(Object.getOwnPropertySymbols(person)); // [Symbol(), Symbol()]