The JavaScript Set methods are now part of Baseline | Blog | web.dev
You can now use the JavaScript Set
methods
to perform set operations like
intersection
,
union
and more.
Sets are an essential data structure in any programming language. Now you can
use JavaScript’s built-in methods to perform set operations. Simplify your set
operations using the following methods:
intersection()
intersection()
returns a new set containing elements in both this set and the given set.
const odds = new Set([1, 3, 5, 7, 9]);
const squares = new Set([1, 4, 9]);
console.log(odds.intersection(squares)); // Set(2) { 1, 9 }
union()
union()
returns a new set containing all elements in this set and the given set.
const evens = new Set([2, 4, 6, 8]);
const squares = new Set([1, 4, 9]);
console.log(evens.union(squares)); // Set(6) { 2, 4, 6, 8, 1, 9 }
difference()
difference()
returns a new set containing elements in this set but not in the given set.
const odds = new Set([1, 3, 5, 7, 9]);
const squares = new Set([1, 4, 9]);
console.log(odds.difference(squares)); // Set(3) { 3, 5, 7 }
symmetricDifference()
symmetricDifference()
returns a new set containing elements that are in either this set or the given
set, but not in both.
const evens = new Set([2, 4, 6, 8]);
const squares = new Set([1, 4, 9]);
console.log(evens.symmetricDifference(squares)); // Set(5) { 2, 6, 8, 1, 9 }
isSubsetOf()
isSubsetOf()
returns a boolean indicating if all elements of this set are in the given set.
const fours = new Set([4, 8, 12, 16]);
const evens = new Set([2, 4, 6, 8, 10, 12, 14, 16, 18]);
console.log(fours.isSubsetOf(evens)); // true
isSupersetOf()
isSupersetOf()
returns a boolean indicating if all elements of the given set are in this set.
const evens = new Set([2, 4, 6, 8, 10, 12, 14, 16, 18]);
const fours = new Set([4, 8, 12, 16]);
console.log(evens.isSupersetOf(fours)); // true
isDisjointFrom()
isDisjointFrom()
Returns a boolean indicating if this set has no elements in common with the
given set.
const primes = new Set([2, 3, 5, 7, 11, 13, 17, 19]);
const squares = new Set([1, 4, 9, 16]);
console.log(primes.isDisjointFrom(squares)); // true
Updating your code to use the built-in methods improves performance and reduces
technical debt.