JavaScript Academy · Lesson

Symbols as Object Keys

Use symbols for non-colliding properties.

Symbols as Keys

A symbol can be used as an object property key. Because each symbol is unique, such a property cannot accidentally collide with any string key.

const id = Symbol("id")
const user = {}
user[id] = 123
console.log(user[id])

To use a symbol as a key in an object literal, wrap it in square brackets as a computed property name.

const id = Symbol("id")
const user = {
  name: "Ann",
  [id]: 99
}
console.log(user[id])