JS: Set.prototype.isDisjointFrom

By Xah Lee. Date: . Last updated: .

(new in JS: ECMAScript 2024)

setA.isDisjointFrom(setB)
  • return true if the union of 2 sets is empty.
  • setB can be a Map.
const xx = new Set([4, 5, 6])
const yy = new Set([7, 8])
console.log(xx.isDisjointFrom(yy))
// true

// isDisjointFrom of 2 map's keys

const mapA = new Map([[4, 0], [5, 0], [6, 0]])
const mapB = new Map([[7, 0], [8, 0]])

console.log((new Set(mapA.keys())).isDisjointFrom(mapB))
// true

JS set operations