How to add an array of values to a Set

While Set API is still very minimalistic, you can use Array.prototype.forEach and shorten your code a bit:

array.forEach(item => mySet.add(item))

// alternative, without anonymous arrow function
array.forEach(mySet.add, mySet)

Here's a functional way, returning a new set:

const set = new Set(['a', 'b', 'c'])
const arr = ['d', 'e', 'f']
const extendedSet = new Set([ ...set, ...arr ])
// Set { 'a', 'b', 'c', 'd', 'e', 'f' }

This is IMO the most elegant

// for a new Set 
const x = new Set([1,2,3,4]);

// for an existing Set
const y = new Set();

[1,2,3,4].forEach(y.add, y);

How about using the spread operator to easily blend your new array items into an existing set?

const mySet = new Set([1,2,3,4])
const additionalSet = [5,6,7,8,9]
mySet = new Set([...mySet, ...additionalSet])

JSFIDDLE

create a new Set:

    //Existing Set
    let mySet = new Set([1,2,3,4,5]);
    //Existing Array
    let array = [6,7,8,9,0];
        
    mySet = new Set(array.concat([...mySet]));
    console.log([...mySet]);
    
    //or single line
    console.log([...new Set([6,7,8,9,0].concat([...new Set([1,2,3,4,5])]))]);

How to add an array of values to a Set

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