Why can [...Set] return an Array?

Question

let mySet = new Set ([1,2,3])
[...mySet] //[1,2,3]

Answer 1

ES6 syntax, data spread operator (...), can convert certain data structures into arrays

Answer 2

ES6 syntax, [...mySet] is a way of writing destructuring assignment, reference: http://es6.ruanyifeng.com/