How can I convert an array to a map and a set in JavaScript?

How can I convert an array to a map and a set in JavaScript?

You can use the Map and Set constructors in JavaScript. For example, to convert an array to a map, you can use new Map(array.map(item => [item.key, item.value])). For a set, simply use new Set(array).

Can you give me a code example for both?

Sure! Here's an example:

const array = [{key: 'a', value: 1}, {key: 'b', value: 2}];
const map = new Map(array.map(item => [item.key, item.value]));
const set = new Set(array.map(item => item.key));

This creates a map with keys 'a' and 'b', and a set with 'a' and 'b'.

What if my array has duplicate values?

If your array has duplicate values, using a Set will automatically remove duplicates. For example:

const array = [1, 2, 2, 3];
const set = new Set(array);
console.log(set); // Output: Set { 1, 2, 3 }