What are the differences between Map and Set in ES6?

What are the differences between Map and Set in ES6?

In ES6, a Map is a collection of key-value pairs, while a Set is a collection of unique values. Maps can have any value as a key, whereas Sets only store unique values.

Can you give me an example of how to use Map and Set?

Sure! For a Map, you can do:

let myMap = new Map();
myMap.set('key1', 'value1');
console.log(myMap.get('key1')); // Output: value1

For a Set:

let mySet = new Set();
mySet.add(1);
mySet.add(2);
mySet.add(1); // This won't add a duplicate
console.log(mySet); // Output: Set { 1, 2 }

Are there any performance differences between them?

Yes, Maps generally have better performance for frequent additions and removals of key-value pairs, while Sets are optimized for storing unique values.

When should I use Map over Set?

Use a Map when you need to associate keys with values, and use a Set when you only need to store unique values without any association.